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1.  Wound Measurement Techniques: Comparing the Use of Ruler Method, 2D Imaging and 3D Scanner 
The statistics on the growing number of non-healing wounds is alarming. In the United States, chronic wounds affect 6.5 million patients. An estimated US $25 billion is spent annually on treatment of chronic wounds and the burden is rapidly growing due to increasing health care costs, an aging population and a sharp rise in the incidence of diabetes and obesity worldwide.1 Accurate wound measurement techniques will help health care personnel to monitor the wounds which will indirectly help improving care.7,9 The clinical practice of measuring wounds has not improved even today.2,3 A common method like the ruler method to measure wounds has poor interrater and intrarater reliability.2,3 Measuring the greatest length by the greatest width perpendicular to the greatest length, the perpendicular method, is more valid and reliable than other ruler based methods.2 Another common method like acetate tracing is more accurate than the ruler method but still has its disadvantages. These common measurement techniques are time consuming with variable inaccuracies. In this study, volumetric measurements taken with a non-contact 3-D scanner are benchmarked against the common ruler method, acetate grid tracing, and 2-D image planimetry volumetric measurement technique. A liquid volumetric fill method is used as the control volume. Results support the hypothesis that the 3-D scanner consistently shows accurate volumetric measurements in comparison to standard volumetric measurements obtained by the waterfill technique (average difference of 11%). The 3-D scanner measurement technique was found more reliable and valid compared to other three techniques, the ruler method (average difference of 75%), acetate grid tracing (average difference of 41%), and 2D planimetric measurements (average difference of 52%). Acetate tracing showed more accurate measurements compared to the ruler method (average difference of 41% (acetate tracing) compared to 75% (ruler method)). Improving the accuracy in measuring chronic wounds might improve overall care of patients with non-healing wounds. This study consistently shows that the 3-D scanner is a more accurate, quicker, and safer method for measuring wounds.
PMCID: PMC4495754  PMID: 26199893
Wounds; Measurement; Ruler method; Acetate tracing; 2D planimetry; 3D scanner
2.  Stress-Mediated Increases in Systemic and Local Epinephrine Impair Skin Wound Healing: Potential New Indication for Beta Blockers 
PLoS Medicine  2009;6(1):e1000012.
Stress, both acute and chronic, can impair cutaneous wound repair, which has previously been mechanistically ascribed to stress-induced elevations of cortisol. Here we aimed to examine an alternate explanation that the stress-induced hormone epinephrine directly impairs keratinocyte motility and wound re-epithelialization. Burn wounds are examined as a prototype of a high-stress, high-epinephrine, wound environment. Because keratinocytes express the β2-adrenergic receptor (β2AR), another study objective was to determine whether β2AR antagonists could block epinephrine effects on healing and improve wound repair.
Methods and Findings
Migratory rates of normal human keratinocytes exposed to physiologically relevant levels of epinephrine were measured. To determine the role of the receptor, keratinocytes derived from animals in which the β2AR had been genetically deleted were similarly examined. The rate of healing of burn wounds generated in excised human skin in high and low epinephrine environments was measured. We utilized an in vivo burn wound model in animals with implanted pumps to deliver β2AR active drugs to study how these alter healing in vivo. Immunocytochemistry and immunoblotting were used to examine the up-regulation of catecholamine synthetic enzymes in burned tissue, and immunoassay for epinephrine determined the levels of this catecholamine in affected tissue and in the circulation. When epinephrine levels in the culture medium are elevated to the range found in burn-stressed animals, the migratory rate of both cultured human and murine keratinocytes is impaired (reduced by 76%, 95% confidence interval [CI] 56%–95% in humans, p < 0.001, and by 36%, 95% CI 24%–49% in mice, p = 0.001), and wound re-epithelialization in explanted burned human skin is delayed (by 23%, 95% CI 10%–36%, p = 0.001), as compared to cells or tissues incubated in medium without added epinephrine. This impairment is reversed by β2AR antagonists, is absent in murine keratinocytes that are genetically depleted of the β2AR, and is reproduced by incubation of keratinocytes with other β2AR-specific agonists. Activation of the β2AR in cultured keratinocytes signals the down-regulation of the AKT pathway, accompanied by a stabilization of the actin cytoskeleton and an increase in focal adhesion formation, resulting in a nonmigratory phenotype. Burn wound injury in excised human skin also rapidly up-regulates the intra-epithelial expression of the epinephrine synthesizing enzyme phenylethanolamine-N-methyltransferase, and tissue levels of epinephrine rise dramatically (15-fold) in the burn wounded tissue (values of epinephrine expressed as pg/ug protein ± standard error of the mean: unburned control, 0.6 ± 0.36; immediately postburn, 9.6 ± 1.58; 2 h postburn, 3.1 ± 1.08; 24 h post-burn, 6.7 ± 0.94). Finally, using an animal burn wound model (20% body surface in mice), we found that systemic treatment with βAR antagonists results in a significant increase (44%, 95% CI 27%–61%, p < 0.00000001) in the rate of burn wound re-epithelialization.
This work demonstrates an alternate pathway by which stress can impair healing: by stress-induced elevation of epinephrine levels resulting in activation of the keratinocyte β2AR and the impairment of cell motility and wound re-epithelialization. Furthermore, since the burn wound locally generates epinephrine in response to wounding, epinephrine levels are locally, as well as systemically, elevated, and wound healing is impacted by these dual mechanisms. Treatment with beta adrenergic antagonists significantly improves the rate of burn wound re-epithelialization. This work suggests that specific β2AR antagonists may be apt, near-term translational therapeutic targets for enhancing burn wound healing, and may provide a novel, low-cost, safe approach to improving skin wound repair in the stressed individual.
Rivkah Isseroff and colleagues describe how stress-induced elevation of epinephrine levels can impair the healing of burns in mice and suggest that β2 adrenergic receptor antagonists may have a role in improving skin wound repair.
Editors' Summary
Skin—the largest organ in the human body—protects the rest of the body against infection by forming an impervious layer over the whole external body surface. Consequently, if this layer is damaged by rubbing, cutting, or burning, it must be quickly and efficiently repaired. Wound repair (healing) involves several different processes. First, the clotting cascade stops bleeding at the wound site and immune system cells attracted into the site remove any bacteria or debris in the wound. Various factors are released by the immune cells and the other cells in and near the damaged area that encourage the migration of several different sorts of cells into the wound. These cells proliferate and prepare the wound for “re-epithelialization.” In this process, keratinocytes (a type of epithelial cell that makes a tough, insoluble protein called keratin; epithelial cells cover all the surfaces of the body) migrate into the wound site and form a new, intact epithelial layer. If any of these processes fail, the result can be a chronic (long-lasting) nonhealing wound. In particular, if the wound does not re-epithelialize, it remains open and susceptible to infection and loss of body fluids.
Why Was This Study Done?
One factor that impairs the repair of skin wounds is stress. In stressful situations (including situations in which wounds are likely to occur), the human body releases several chemicals that prepare the body for “fight or flight,” including cortisol and epinephrine (also called adrenaline). Most scientists ascribe the effects of stress on wound healing to stress-induced increases in cortisol, but might stress-induced epinephrine also affect wound healing? In this study, the researchers test whether epinephrine impairs keratinocyte migration and re-epithelialization of burn wounds (keratinocytes have a receptor for epinephrine called the β2 adrenergic receptor [β2AR] on their cell surface that allows them to respond to epinephrine). They chose to study burn wounds for two reasons. First, major burns cause a massive release of stress chemicals into the bloodstream that raises blood levels (systemic levels) of cortisol and epinephrine for days or weeks after the initial trauma. Second, despite recent therapeutic advances, many people still die from major burns (4,000 every year in the USA alone) so there is a pressing need for better ways to treat this type of wound.
What Did the Researchers Do and Find?
The researchers investigated the effects of epinephrine on wound healing in three types of experiments. First, they looked at the effect of epinephrine on keratinocytes growing in dishes (in vitro experiments). Levels of epinephrine similar to those in the blood of stressed individuals greatly inhibited the motility and migration of human keratinocytes (isolated from the foreskin of newborn babies) and of mouse keratinocytes. It also inhibited the repair of scratch wounds made in monolayers of keratinocytes growing on dishes. Treatment of the cultures with a β2AR antagonist (a chemical that prevents epinephrine activating the β2AR) reversed the effects of epinephrine. In addition, the migration of mouse keratinocytes that had been genetically altered so that they did not express β2AR was not inhibited by epinephrine. Next, the researchers investigated the healing of burn wounds made in small pieces of human skin growing in dishes (ex vivo experiments). Burn injuries rapidly increased the amount of epinephrine in these tissue explants, they report, and treatment of the explants with a βAR antagonist (an inhibitor of all types of βARs) greatly increased wound re-epithelialization. Finally, the researchers report that the re-epithelialization of burn wounds in living mice was improved when the mice were treated with a β2AR antagonist.
What Do These Findings Mean?
These findings reveal a second pathway by which stress can impair wound healing. They show that stress-induced increases in systemic and local epinephrine activate β2ARs on keratinocytes and that this activation inhibits keratinocyte motility and wound re-epithelialization. Although results obtained in animals do not always reflect what happens in people, the finding that the treatment of mice with β2AR antagonists improves the rate of burn wound re-epithelialization, suggests that beta blockers—drugs that inhibit all βARs and that are widely used to treat high blood pressure and to prevent heart disease—or specific β2AR antagonists might provide a new therapeutic approach to the treatment of burns and, perhaps, chronic nonhealing wounds.
Additional Information.
Please access these Web sites via the online version of this summary at
Wikipedia has pages on wound healing, burn injuries, and epinephrine (Note: Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
The MedlinePlus Encyclopedia has a page on burns (in English and Spanish)
MedlinePlus provides links to other information on burns (in English and Spanish)
PMCID: PMC2621262  PMID: 19143471
3.  A Comparison of Wound Area Measurement Techniques: Visitrak Versus Photography 
Eplasty  2011;11:e18.
Objective: To investigate whether a cheap, fast, easy, and widely available photographic method is an accurate alternative to Visitrak when measuring wound area in cases where a non–wound-contact method is desirable. Methods: The areas of 40 surgically created wounds on porcine models were measured using 2 techniques—Visitrak and photography combined with ImageJ. The wounds were photographed with a ruler included in the photographic frame to allow ImageJ calibration. The images were uploaded to a computer and opened with ImageJ. The wound outline was defined from the photographic image using a digital pad, and the ImageJ software calculated the wound area. The Visitrak method involved a 2-layered transparent Visitrak film placed on the wound and the outline traced onto the film. The top layer containing the tracing was retraced onto the Visitrak digital pad using the Visitrak pen and the software calculated the wound area. Results: The average wound area using the photographic method was 52.264 cm2 and using Visitrak was 51.703 cm2. The mean difference in wound area was 0.560 cm2. Using a 2-tailed paired T test, the T statistic was 1.285 and the value .206, indicating no statistical difference between the two methods. The interclass correlation coefficient was 0.971. Conclusions: The photographic method is an accurate alternative to Visitrak for measuring wound area, with no statistical difference in wound area measurement demonstrated during this study. The photographic method is a more appropriate technique for clean and uncontaminated wounds, as contact with the wound bed is avoided.
PMCID: PMC3080766  PMID: 21559060
4.  Negative Pressure Wound Therapy 
Executive Summary
This review was conducted to assess the effectiveness of negative pressure wound therapy.
Clinical Need: Target Population and Condition
Many wounds are difficult to heal, despite medical and nursing care. They may result from complications of an underlying disease, like diabetes; or from surgery, constant pressure, trauma, or burns. Chronic wounds are more often found in elderly people and in those with immunologic or chronic diseases. Chronic wounds may lead to impaired quality of life and functioning, to amputation, or even to death.
The prevalence of chronic ulcers is difficult to ascertain. It varies by condition and complications due to the condition that caused the ulcer. There are, however, some data on condition-specific prevalence rates; for example, of patients with diabetes, 15% are thought to have foot ulcers at some time during their lives. The approximate community care cost of treating leg ulcers in Canada, without reference to cause, has been estimated at upward of $100 million per year.
Surgically created wounds can also become chronic, especially if they become infected. For example, the reported incidence of sternal wound infections after median sternotomy is 1% to 5%. Abdominal surgery also creates large open wounds. Because it is sometimes necessary to leave these wounds open and allow them to heal on their own (secondary intention), some may become infected and be difficult to heal.
Yet, little is known about the wound healing process, and this makes treating wounds challenging. Many types of interventions are used to treat wounds.
Current best practice for the treatment of ulcers and other chronic wounds includes debridement (the removal of dead or contaminated tissue), which can be surgical, mechanical, or chemical; bacterial balance; and moisture balance. Treating the cause, ensuring good nutrition, and preventing primary infection also help wounds to heal. Saline or wet-to-moist dressings are reported as traditional or conventional therapy in the literature, although they typically are not the first line of treatment in Ontario. Modern moist interactive dressings are foams, calcium alginates, hydrogels, hydrocolloids, and films. Topical antibacterial agents—antiseptics, topical antibiotics, and newer antimicrobial dressings—are used to treat infection.
The Technology Being Reviewed
Negative pressure wound therapy is not a new concept in wound therapy. It is also called subatmospheric pressure therapy, vacuum sealing, vacuum pack therapy, and sealing aspirative therapy.
The aim of the procedure is to use negative pressure to create suction, which drains the wound of exudate (i.e., fluid, cells, and cellular waste that has escaped from blood vessels and seeped into tissue) and influences the shape and growth of the surface tissues in a way that helps healing. During the procedure, a piece of foam is placed over the wound, and a drain tube is placed over the foam. A large piece of transparent tape is placed over the whole area, including the healthy tissue, to secure the foam and drain the wound. The tube is connected to a vacuum source, and fluid is drawn from the wound through the foam into a disposable canister. Thus, the entire wound area is subjected to negative pressure. The device can be programmed to provide varying degrees of pressure either continuously or intermittently. It has an alarm to alert the provider or patient if the pressure seal breaks or the canister is full.
Negative pressure wound therapy may be used for patients with chronic and acute wounds; subacute wounds (dehisced incisions); chronic, diabetic wounds or pressure ulcers; meshed grafts (before and after); or flaps. It should not be used for patients with fistulae to organs/body cavities, necrotic tissue that has not been debrided, untreated osteomyelitis, wound malignancy, wounds that require hemostasis, or for patients who are taking anticoagulants.
Review Strategy
The inclusion criteria were as follows:
Randomized controlled trial (RCT) with a sample size of 20 or more
Human study
Published in English
Summary of Findings
Seven international health technology assessments on NPWT were identified. Included in this list of health technology assessments is the original health technology review on NPWT by the Medical Advisory Secretariat from 2004. The Medical Advisory Secretariat found that the health technology assessments consistently reported that NPWT may be useful for healing various types of wounds, but that its effectiveness could not be empirically quantified because the studies were poorly done, the patient populations and outcome measures could not be compared, and the sample sizes were small.
Six RCTs were identified that compared NPWT to standard care. Five of the 6 studies were of low or very low quality according to Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria. The low and very low quality RCTs were flawed owing to small sample sizes, inconsistent reporting of results, and patients lost to follow-up. The highest quality study, which forms the basis of this health technology policy assessment, found that:
There was not a statistically significant difference (≥ 20%) between NPWT and standard care in the rate of complete wound closure in patients who had complete wound closure but did not undergo surgical wound closure (P = .15).
The authors of this study did not report the length of time to complete wound closure between NPWT and standard care in patients who had complete wound closure but who did not undergo surgical wound closure
There was no statistically significant difference (≥ 20%) in the rate of secondary amputations between the patients that received NPWT and those that had standard care (P = .06)
There may be an increased risk of wound infection in patients that receive NPWT compared with those that receive standard care.
Based on the evidence to date, the clinical effectiveness of NPWT to heal wounds is unclear. Furthermore, saline dressings are not standard practice in Ontario, thereby rendering the literature base irrelevant in an Ontario context. Nonetheless, despite the lack of methodologically sound studies, NPWT has diffused across Ontario.
Discussions with Ontario clinical experts have highlighted some deficiencies in the current approach to wound management, especially in the community. Because NPWT is readily available, easy to administer, and may save costs, compared with multiple daily conventional dressing changes, it may be used inappropriately. The discussion group highlighted the need to put in place a coordinated, multidisciplinary strategy for wound care in Ontario to ensure the best, continuous care of patients.
PMCID: PMC3379164  PMID: 23074484
5.  Use of Standardized, Quantitative Digital Photography in a Multicenter Web-based Study 
Eplasty  2009;9:e4.
Objective: We developed a Web-based, blinded, prospective, randomized, multicenter trial, using standardized digital photography to clinically evaluate hand burn depth and accurately determine wound area with digital planimetry. Methods: Photos in each center were taken with identical digital cameras with standardized settings on a custom backdrop developed at Wake Forest University containing a gray, white, black, and centimeter scale. The images were downloaded, transferred via the Web, and stored on servers at the principal investigator's home institution. Color adjustments to each photo were made using Adobe Photoshop 6.0 (Adobe, San Jose, Calif). In an initial pilot study, model hands marked with circles of known areas were used to determine the accuracy of the planimetry technique. Two-dimensional digital planimetry using SigmaScan Pro 5.0 (SPSS Science, Chicago, Ill) was used to calculate wound area from the digital images. Results: Digital photography is a simple and cost-effective method for quantifying wound size when used in conjunction with digital planimetry (SigmaScan) and photo enhancement (Adobe Photoshop) programs. The accuracy of the SigmaScan program in calculating predetermined areas was within 4.7% (95% CI, 3.4%–5.9%). Dorsal hand burns of the initial 20 patients in a national study involving several centers were evaluated with this technique. Images obtained by individuals denying experience in photography proved reliable and useful for clinical evaluation and quantification of wound area. Conclusion: Standardized digital photography may be used quantitatively in a Web-based, multicenter trial of burn care. This technique could be modified for other medical studies with visual endpoints.
PMCID: PMC2627310  PMID: 19212431
6.  Topical Silver for Infected Wounds 
Journal of Athletic Training  2009;44(5):531-533.
Vermeulen H, van Hattem JM, Storm-Versloot MN, Ubbink DT. Topical silver for treating infected wounds. Cochrane Database Syst Rev. 2007(1);CD005486.
Clinical Question:
What is the clinical evidence base for silver dressings in the management of contaminated and infected acute and chronic wounds?
Data Sources:
Investigations were identified by Cochrane Wounds Group Specialized Register (2006), CENTRAL (2006), MEDLINE (2002–2006), EMBASE (2002–2006), CINAHL (2002–2006), and digital dissertations (2006) searches. Product manufacturers were contacted to identify additional eligible studies. The search terms included wound infection, surgical wound infection, ulcer, wound healing, and silver.
Study Selection:
Each study fulfilled the following criteria: (1) The study was a randomized controlled trial of human participants that compared dressings containing silver with any dressings without silver, dressings with other antiseptics, or dressings with different dosages of silver. (2) The participants were aged 18 years and older with contaminated and infected open wounds of any cause. (3) The study had to evaluate the effectiveness of the dressings using an objective measure of healing. No language or publication status restrictions were imposed, and participants could be recruited in any care setting. Studies were excluded if the wounds were ostomies (surgically formed passages).
Data Extraction:
Study quality assessment was conducted independently by 3 authors using the Dutch Institute for Health Care Improvement and Dutch Cochrane Centre protocols. Characteristics of the study, participants, interventions, and outcome measures were extracted by one author and verified by a second using a standard form. The principal outcome measure was healing (time to complete healing, rate of change in wound area and volume, number and proportion of wounds healed within trial period). Secondary measures were adverse events (eg, pain, maceration, erythema), dressing leakage, and wound odor. Based on the unique comparisons in the studies, a meta-analysis was not conducted. As a result, summary estimates of treatment effect were calculated for each outcome comparison. RevMan software (version 4.2; Cochrane Centre, Oxford, United Kingdom) was used for statistical analysis.
Main Results:
Specific search criteria identified 31 studies for review, of which 3 met the inclusion and exclusion criteria. Lack of randomization and absence of wound infections excluded the majority of studies from the review. In the 3 studies selected, silver-containing dressings were compared with nonsilver dressings and dressings with other antimicrobials. One group used a silver-containing foam dressing and a nonsilver foam dressing; another group used a silver-containing alginate and a nonsilver alginate; and a third group used a silver-containing foam and various dressings (nonsilver foams, alginates, hydrocolloids, and gauze and other antimicrobial dressings). Sample sizes ranged between 99 and 619 participants. Most of the wounds in the included studies were pressure, diabetic, and venous leg ulcers. Wound infection was subjectively defined by 1 group as the presence of 2 or more signs and symptoms (eg, continuous pain, erythema, heat, or moderate to high levels of exudate) and by the other 2 groups as signs of critical colonization (eg, delayed healing, increased pain and exudate levels, discoloration, and odor). The primary measure in the included studies was healing outcome. The 3 groups used various assessments of healing, including relative and absolute reduction in wound area and number of wounds healed during the trial period. The trial period in each study was 4 weeks. In the 3 trials, the authors randomized the participants to the treatment groups.
Examining healing, one group (129 participants) compared Contreet silver foam (Coloplast A/S, Humlebaek, Denmark) with Allevyn foam (Smith & Nephew, St-Laurent, Quebec, Canada). The authors reported no differences for rates of complete healing (risk difference [RD]  =  0.00, 95% confidence interval [CI]  =  −0.09, 0.09) and median wound area reduction (weighted mean difference [WMD]  =  −0.30 cm2, 95% CI  =  −2.92, 2.35). However, Contreet was favored over Allevyn (P  =  .034) for median relative reduction in wound area (WMD  =  −15.70 cm2, 95% CI  =  −29.5, −1.90). One group (99 participants) compared Silvercel silver alginate (Johnson & Johnson Wound Management, Somerville, NJ) with Algosteril alginate (Johnson & Johnson Wound Management). The authors found no differences in rates of complete healing (RD  =  0.00, 95% CI  =  −0.06, 0.05), mean absolute (WMD  =  4.50 cm2, 95% CI  =  −0.93, 9.93) and relative wound area reduction (WMD  =  −0.30 cm2, 95% CI  =  −17.08, 16.48), or healing rate per day (week 1 to 4) (WMD  =  0.16 cm2, 95% CI  =  −0.03, 0.35). One group (619 participants) compared Contreet with various dressings (nonsilver foams, alginates, hydrocolloids, and gauze and other antimicrobial dressings). For median relative wound area reduction, the authors noted a superiority of Contreet over the various dressings (P  =  .0019).
Examining secondary outcomes, 2 groups used subjective analysis to compare adverse reactions among the dressings. One group reported no difference between Contreet (in satellite ulcers, deterioration of periwound tissue) and Allevyn (in satellite ulcers, maceration, eczema) (RD  =  0.02, 95% CI  =  −0.07, 0.12), and one group found no difference between Silvercel (in pain during dressing change, eczema, periwound erythema, maceration) and Algosteril (in pain during dressing change, eczema, erythema) (RD  =  −0.01, 95% CI  =  −0.12, 0.11). Two groups subjectively assessed leakage among silver and nonsilver dressings. The data from one group demonstrated superiority of Contreet over Allevyn (P  =  .002; RD  =  −0.30, 95% CI  =  −0.47, −0.13), and one group found Contreet better than various dressings (eg, nonsilver foams, alginates, hydrocolloids, and gauze, and other antimicrobial dressings) (P  =  .0005; RD  =  −0.11, 95% CI  =  −0.18, −0.05). Using a subjective 4-point scale, one group compared silver and nonsilver dressings and reported a difference favoring Contreet over Allevyn in terms of wound odor (P  =  .030; RD  =  −0.19, 95% CI  =  −0.36, −0.03).
Overall, this review provides no clear evidence to support the use of silver-containing foam and alginate dressings in the management of infected chronic wounds for up to 4 weeks. However, the use of silver foam dressings resulted in a greater reduction in wound size and more effective control of leakage and odor than did use of nonsilver dressings. Randomized controlled trials using standardized outcome measures and longer follow-up periods are needed to determine the most appropriate dressing for contaminated and infected acute and chronic wounds.
PMCID: PMC2742464  PMID: 19771293
antiseptics; moist dressings; critical colonization; contamination
7.  A novel and accurate technique of photographic wound measurement 
Wound measurement is an important aspect of wound management. Though there are many techniques to measure wounds, most of them are either cumbersome or too expensive.
To introduce a simple and accurate technique by which wounds can be accurately measured.
Settings and Design:
This is a comparative study of 10 patients whose wounds were measured by three techniques, i.e. ruler, graph and our technique.
Materials and Methods:
The graph method was taken as the control measurement. The extent of deviation in wound measurements with our method was compared with the standard technique. The statistical analysis used was ANOVA.
The ruler method was highly inaccurate and overestimated the wound size by nearly 50%. Our technique remained consistent and accurate with the percentage of over or underestimation being 2-4% in comparison with the graph method.
This technique is simple and accurate and is an inexpensive and non-invasive method to accurately measure wounds.
PMCID: PMC3495395  PMID: 23162244
Digital planimetry; photography; wound measurement
8.  Impact and Predictors of Noncircular Left Ventricular Outflow Tract Shapes on Estimating Aortic Stenosis Severity by Means of Continuity Equations 
Texas Heart Institute Journal  2015;42(1):16-24.
Determining aortic stenosis (AS) severity is clinically important. Calculating aortic valve (AV) area by means of the continuity equation assumes a circular left ventricular outflow tract (LVOT). The full impact of this assumption in calculating AV area is unknown. Predictors of noncircular LVOT shape in patients with AS are undefined.
In 109 adult patients with AS who underwent multiplanar transesophageal echocardiography, we calculated AV area by means of the standard continuity method and by a modified method involving planimetric LVOT area.
We found 54 circular, 37 horizontal-oval, 8 vertical-oval, and 10 irregular LVOTs. Area derived by direct planimetry correlated better with the modified than the standard continuity method (r=0.89 vs r=0.85; both P=0.0001). Valve areas of patients with mild, moderate, or severe AS by planimetry were more often mischaracterized with use of the standard than modified method (29 vs 18; P <0.0001). Horizontal-oval AV area derived by planimetry (1.28 ± 0.55 cm2) was underestimated by the standard method (1.05 ± 0.47 cm2; P=0.001), but not by the modified method. Congenital AV morphology and low cardiac index were the only multivariate predictors of horizontal-oval shape. Low cardiac index was the only predictor of noncircular shape.
More than half our patients with AS had noncircular LVOTs. Using the modified method reduces mischaracterizations of AS severity. Congenital AV morphology and low cardiac index predict horizontal-oval or noncircular shape. These data suggest the value of direct LVOT measurement to calculate AS severity in patients who have congenital AV or a low cardiac index.
PMCID: PMC4378036  PMID: 25873793
Aortic valve/anatomy & histology; aortic valve stenosis/physiopathology; cardiac output; echocardiography, transesophageal/methods/standards; evaluation studies as topic; heart valve diseases/diagnosis/ultrasonography; predictive value of tests; severity of illness index; ventricular outflow obstruction/ultrasonography
9.  Estimation of Laceration Length by Emergency Department Personnel 
Documentation and billing for laceration repair involves a description of wound length. We designed this study to test the hypothesis that emergency department (ED) personnel can accurately estimate wound lengths without the aid of a measuring device.
This was a single-center prospective observational study performed in an academic ED. Seven wounds of varying lengths were simulated by creating lacerations on purchased pigs’ ears and feet. We asked healthcare providers, defined as nurses and physicians working in the ED, to estimate the length of each wound by visual inspection. Length estimates were given in centimeters (cm) and inches. Estimated lengths were considered correct if the estimate was within 0.5 cm or 0.2 inches of the actual length. We calculated the differences between estimated and actual laceration lengths for each laceration and compared the accuracy of physicians to nurses using an unpaired t-test.
Thirty-two physicians (nine faculty and 23 residents) and 16 nurses participated. All subjects tended to overestimate in cm and inches. Physicians were able to estimate laceration length within 0.5 cm 36% of the time and within 0.2 inches 29% of the time. Physicians were more accurate at estimating wound lengths than nurses in both cm and inches. Both physicians and nurses were more accurate at estimating shorter lengths (<5.0 cm) than longer (>5.0 cm).
ED personnel are often unable to accurately estimate wound length in either cm or inches and tend to overestimate laceration lengths when based solely on visual inspection.
PMCID: PMC4251246  PMID: 25493145
10.  Tissue Adhesives for Simple Traumatic Lacerations 
Journal of Athletic Training  2008;43(2):222-224.
Reference/Citation: Farion K, Osmond MH, Hartling L, et al. Tissue adhesives for traumatic lacerations in children and adults. Cochrane Database Syst Rev. 2001(4);CD003326.
Clinical Question: What is the clinical evidence base for tissue adhesives in the management of simple traumatic lacerations?
Data Sources: Studies were identified by searches of the following databases: Cochrane Wounds Group Specialized Trials Register (September 2003), Cochrane Central Register of Controlled Trials (CENTRAL) (CDROM 2003, issue 3), MEDLINE (1966 to September 2003, week 1), EMBASE (1988 to 2003, week 36), Web of Science Science Citation Index (1975 to September 13, 2003) and various clinical trials registers (September 2003). Investigators and product manufacturers were contacted to identify additional eligible studies. The search terms included wounds and injuries, laceration, face injury, nose injury, tissue adhesives, and acrylates.
Study Selection: Each study fulfilled the following criteria: (1) The study was a randomized controlled trial that compared tissue adhesives with standard wound closure (SWC) (sutures, staples, adhesive strips) or tissue adhesive with tissue adhesive. (2) The wounds were acute, linear lacerations less than 12 hours old, resulting from blunt or sharp trauma. (3) The wound length, width, and depth allowed for approximation of the edges with minimal tension after deep sutures were placed, if required. Studies were included with no language or publication status restriction, with participants of any age recruited in an emergency department, outpatient clinic, walk-in clinic, or other primary care setting. Studies were excluded if the wounds were stellate lacerations, puncture wounds, mammalian bites, infected, heavily contaminated or devitalized, crossing joints or mucocutaneous junctions, in hair-bearing areas, or in patients with keloid formation or chronic illness.
Data Extraction: The characteristics of the study and participants, interventions, outcome measures, and findings were extracted by one author and verified by a second using a standard form. The primary measure was cosmetic outcome. Secondary measures were pain with the procedure, time to complete the procedure, and complications (erythema, infection, discharge, need for delayed closure, and dehiscence). Studies were divided into 2 groups as follows: group 1, comparisons among tissue adhesives with SWC, and group 2, comparisons among different tissue adhesives. All eligible studies were assessed for methodologic quality independently by 2 investigators using the Jadad Scale, which evaluates randomization, double blinding, withdrawals, and dropouts and is scored on a 5-point (maximum) scale. The data from the tissue adhesive and SWC studies were pooled and analyzed with a random-effects model. The I 2 statistic was used to determine heterogeneity among the studies. χ 2 analysis was performed to compare participant age, wound location, and type of tissue adhesive among the studies. The data from the studies comparing tissue adhesives were pooled and analyzed using a fixed-effects model.
Main Results: The search criteria identified 39 eligible studies, of which 11 met the inclusion criteria. In 10 studies, a tissue adhesive was compared with SWC. Five groups used butylcyanoacrylate, and 5 used octylcyanoacrylate. For SWC, 6 groups used sutures, 2 used adhesive strips, and 2 used a combination of methods, although most used sutures. Six studies were limited to pediatric patients and 2 to adult patients; 2 included patients of any age. Wounds were limited to facial lacerations in 2 pediatric studies and 1 group with patients of any age. Lacerations requiring deep sutures were excluded in 4 studies. One group compared tissue adhesives (butylcyanoacrylate and octylcyanoacrylate) among pediatric patients with facial lacerations not requiring deep sutures. In the 11 included studies, authors of 9 randomized and evaluated 1 laceration per patient, whereas 2 groups included patients with more than 1 laceration. In 1 group, each laceration was independently randomized and evaluated, and the other group randomized the patient and assigned all lacerations to a treatment group (tissue adhesive with SWC or tissue adhesive with tissue adhesive). The sample sizes ranged between 60 and 163 lacerations, and all 11 studies were performed in emergency departments.
The primary measure in all included studies was cosmetic outcome. The majority of groups used the Cosmetic Visual Analogue Scale, the Wound Evaluation Score, or a combination of these measures. Three groups measured cosmetic outcome with nonvalidated scoring systems. Assessment time periods were grouped and reported at (1) 5 to 14 days, (2) 1 to 3 months, and (3) 9 to 12 months after wound closure. Secondary outcomes were pain (as noted on visual analogue scale) and time to complete the procedure (as mean number of minutes). The 11 studies scored from 1 to 3 on the Jadad Scale. Adequate allocation concealment was reported in only 1 group.
Examining cosmetic outcome, 8 groups (565 lacerations) used the Cosmetic Visual Analogue Scale to compare tissue adhesives and SWC. The authors reported no significant differences in scores at the time periods of 5 to 14 days, 1 to 3 months, and 9 to 12 months. A subgroup analysis showed a significant ( P = .005) superiority of butylcyanoacrylate over SWC at 1 to 3 months. Using the Wound Evaluation Score, 4 studies (364 lacerations) compared tissue adhesives with SWC. No significant differences in cosmetic scores were found at 5 to 14 days, 1 to 3 months, or 9 to 12 months. One group (83 lacerations) compared butylcyanoacrylate with octylcyanoacrylate and reported no significant differences in cosmetic scores using the Cosmetic Visual Analogue Scale at 1 to 3 months and the Wound Evaluation Score at 5 to 14 days and 1 to 3 months.
Examining secondary outcomes, 6 groups (570 lacerations) compared tissue adhesives with SWC using the visual analogue scale for pain. Scores reported by parents, patients, physicians, and nurses significantly favored tissue adhesives. In 6 studies (584 lacerations), tissue adhesives were significantly favored over SWC in time to complete the procedure. For complication outcomes, 8 groups (727 lacerations) demonstrated significantly fewer incidences of erythema and an increased risk of dehiscence with tissue adhesives compared with SWC. No significant differences were shown for infection, delayed closure, or discharge. Among 83 lacerations, 1 group compared butylcyanoacrylate with octylcyanoacrylate and reported no significant differences in combined patient-reported and parent-reported visual analogue pain scores, time to complete the procedure, dehiscence, or infection.
Conclusions: This review provides evidence that tissue adhesives are an option to SWC (sutures, staples, adhesive strips) for the management of simple traumatic lacerations. Overall, no significant differences were found in cosmetic scores at the reported assessment periods between tissue adhesives and SWC. At 1 to 3 months, a subgroup analysis significantly favored butylcyanoacrylate over SWC. Tissue adhesives significantly lowered the time to complete the procedure, levels of pain, and rate of erythema. However, the data revealed a significant increase in the rate of dehiscence with the use of tissue adhesives when compared with SWC. The low methodologic quality of the evidence should be considered in the interpretation of the findings.
PMCID: PMC2267332  PMID: 18345349
wound closure; tissue bonding; open wounds
11.  Comparison of Digital Planimetry and Ruler Technique To Measure ABSSSI Lesion Sizes in the ESTABLISH–1 Study 
Surgical Infections  2014;15(2):105-110.
Background: In August 2010, the U.S. Food and Drug Administration issued draft guidelines for developing antibiotics for treating acute bacterial skin and skin structure infections (ABSSSI), with the outcome measure of such treatment relying primarily on the cessation of spread or on the decrease in size of skin lesions at 48–72 h after the initiation of such treatment. In 2012, the Foundation for the National Institutes of Health proposed an interim outcome measure defined as a reduction in lesion size by ≥20% at a 48–72 h examination. These recent changes make it necessary to identify reliable methods for measuring the lesions in acute infections of the skin.
Methods: In the first study of the Efficacy and Safety of 6-day Oral Tedizolid in Acute Bacterial Skin and Skin Structure Infections vs. 10-day Oral Linezolid Therapy (ESTABLISH–1), the sizes of ABSSSI lesions were evaluated with the two methodologies of: (1) Digital planimetry (DP) of photographed lesions, and (2) a ruler technique (RT) with measurement of the longest head-to-toe length and greatest perpendicular width of lesions, to compare the respective response rates of lesions to the two antimicrobial regimens in the study.
Results: The RT method and DP showed similar percentages of subjects in which treatment stopped the spread of ABSSSI lesions (93.2% vs. 94.2%, respectively) but showed less agreement for a reduction in lesion size, of ≥20% (87.7% vs. 62.0%, respectively) across all categories of lesions (cellulitis/erysipelas, major cutaneous abscess, and acute wound infection) at 48–72 h after the initiation of treatment.
Conclusion: The results of the ESTABLISH–1 study show that both the RT method and DP are consistent and reliable techniques for measuring the sizes of ABSSSI lesions. Ultimately, changes in lesion size, rather than the absolute value of lesion size, will be used to assess the outcomes of treatment for ABSSSI in clinical research.
PMCID: PMC3993017  PMID: 24450727
12.  Planimetry of aortic valve area using multiplane transoesophageal echocardiography is not a reliable method for assessing severity of aortic stenosis. 
Heart  1997;78(1):68-73.
OBJECTIVE: To assess the reliability of aortic valve area planimetry by multiplane transoesophageal echocardiography (TOE) in aortic stenosis. DESIGN: Study of the diagnostic value of aortic valve area planimetry using multiplane TOE, compared with catheterisation and the continuity equation, both being considered as criterion standards. SETTING: University hospital. PATIENTS: 49 consecutive patients (29 male, 20 female, aged 44 to 82 years, average 66.6 (SD 8.5)), referred for haemodynamic evaluation of an aortic stenosis, were enrolled in a prospective study. From this sample, 37 patients were eligible for the final analysis. METHODS: Transthoracic and multiplane transoesophageal echocardiograms were performed within 24 hours before catheterisation. At transthoracic echo, aortic valve area was calculated by the continuity equation. At TOE, the image of the aortic valve opening was obtained with a 30-65 degrees rotation of the transducer. Numerical dynamic images were stored on optical discs for off-line analysis and were reviewed by two blinded observers. Catheterisation was performed in all cases and aortic valve area was calculated by the Gorlin formula. RESULTS: Feasibility of the method was 92% (48/52). The agreement between aortic valve area measured at TOE (mean 0.88 (SD 0.35) cm2) and at catheterisation (0.79 (0.24) cm2) was very poor. The same discrepancies were found between TOE and the continuity equation (0.72 (0.26) cm2). TOE planimetry overestimated aortic valve area determined by the two other methods. Predictive positive and negative values of planimetry to detect aortic valve area < 0.75 cm2 were 62% (10/16) and 43% (9/21) respectively. CONCLUSIONS: Planimetry of aortic valve area by TOE is difficult and less accurate than the continuity equation for assessing the severity of aortic stenosis.
PMCID: PMC484867  PMID: 9290405
13.  Hyperbaric Oxygen Therapy for Non-Healing Ulcers in Diabetes Mellitus 
Executive Summary
To examine the effectiveness and cost-effectiveness of hyperbaric oxygen therapy (HBOT) to treat people with diabetes mellitus (DM) and non-healing ulcers. This policy appraisal systematically reviews the published literature in the above patient population, and applies the results and conclusions of the review to current health care practices in Ontario, Canada.
Although HBOT is an insured service in Ontario, the costs for the technical provision of this technology are not covered publicly outside the hospital setting. Moreover, access to this treatment is limited, because many hospitals do not offer it, or are not expanding capacity to meet the demand.
Clinical Need
Diabetes mellitus is a chronic disease characterized by an increase in blood sugar that can lead to many severe conditions such as vision, cardiac, and vascular disorders. The prevalence of DM is difficult to estimate, because some people who have the condition are undiagnosed or may not be captured through data that reflect access to the health care system. The Canadian Diabetic Association estimates there are about 2 million people in Canada with diabetes (almost 7% of the population). According to recent data, the prevalence of DM increased from 4.72% of the population aged 20 years and over in 1995, to 6.19% of the population aged 20 years and over in 1999, or about 680,900 people in 1999. Prevalence estimates expanded to 700,000 in 2003.
About 10% to 15% of people with DM develop a foot wound in their lifetimes because of underlying peripheral neuropathy and peripheral vascular disease. This equals between 70,000 and 105,000 people in Ontario, based on the DM prevalence estimate of 700,000 people. Without early treatment, a foot ulcer may fester until it becomes infected and chronic. Chronic wounds are difficult to heal, despite medical and nursing care, and may lead to impaired quality of life and functioning, amputation, or even death.
The Technology
Hyperbaric oxygen therapy has been in use for about 40 years. It is thought to aid wound healing by supplying oxygen to the wound. According to the Hyperbaric Oxygen Therapy Association, HBOT acts as a bactericidal, stops toxin production, and promotes tissue growth to heal difficult wounds.
During the procedure, a patient is placed in a compression chamber with increased pressure between 2.0 and 2.5 atmospheres absolute for 60 to 120 minutes, once or twice daily. In the chamber, the patient inhales 100% oxygen. Treatment usually runs for 15 to 20 sessions.
Noted complications are rare but may include claustrophobia; ear, sinus, or lung damage due to pressure; temporary worsening of short sightedness; and oxygen poisoning. Careful monitoring during the treatment sessions and follow-up by a trained health care provider is recommended.
Review Strategy
The aims of this health technology policy appraisal were to assess the effectiveness, safety, and cost-effectiveness of HBOT, either alone, or as an adjunct, compared with the standard treatments for non-healing foot or leg ulcers in patients with DM. The following questions were asked:
Alone or as an adjunct therapy, is HBOT more effective than other therapies for non-healing foot or leg ulcers in patients with DM?
If HBOT is effective, what is the incremental benefit over and above currently used strategies?
When is the best time in a wound treatment strategy to use HBOT?
What is the best treatment algorithm with HBOT?
The Medical Advisory Secretariat searched for health technology assessments in the published and grey literature. The search yielded 4 reports, which were published from 2000 to 2005. The most recent from the Cochrane Collaboration had a literature review and analysis of randomized control trials to 2003.
As an update to this review, as per the standard Medical Advisory Secretariat systematic review strategy, the abstracts of peer-reviewed publications were identified using Ovid MEDLINE, EMBASE, MEDLINE in-process and not-yet-indexed citations, Cochrane Database of Systematic Reviews, Cochrane CENTRAL, and INAHTA using key words and searching from January 1, 2003 to 2004.
The criteria for inclusion were as follows:
Patients with diabetes
Live human study
English-language study
HBOT as adjunctive therapy or alone
Randomized control trial
The number of excluded studies included the following:
2 animal studies
13 focus on condition other than DM
8 review/protocol for HBOT use
3 HBOT not focus of report
2 health technology assessments (2)
1 non-RCT
Outcomes of interest were wound healing and prevention of amputation.
The search yielded 29 articles published between 2003 and 2004. All 29 of these were excluded, as shown beside the exclusion criteria above. Therefore, this health technology policy assessment focused exclusively on the most recently published health technology assessments and systematic reviews.
Summary of Findings
Four health technology assessments and reviews were found. Cochrane Collaboration researchers published the most recent review in 2005. They included only randomized controlled trials and conducted a meta-analysis to examine wound healing and amputation outcomes. They found that, based on findings from 118 patients in 3 studies, HBOT may help to prevent major amputation (relative risk, 0.31; 95% confidence interval [CI], 0.13–0.71) with a number needed to treat (NNT) of 4 (95% CI, 3–11). They noted, however, that the point estimates derived from trials were not well reported, and had varying populations with respect to wound severity, HBOT regimens, and outcome measures. These noted limitations rendered the comparison of results from the trials difficult. Further, they suggested that the evidence was not strong enough to suggest a benefit for wound healing in general or for prevention of minor amputations.
The Medical Advisory Secretariat also evaluated the studies that the Cochrane Collaboration used in their analysis, and agreed with their evaluation that the quality of the evidence was low for major and minor amputations, but low to moderate for wound healing, suggesting that the results from new and well-conducted studies would likely change the estimates calculated by Cochrane and others.
In 2003, the Ontario Health Technology Advisory Committee recommended a more coordinated strategy for wound care in Ontario to the Ministry of Health and Long-term Care. This strategy has begun at the community care and long-term care institution levels, but is pending in other areas of the health care system.
There are about 700,000 people in Ontario with diabetes; of these, 10% to 15% may have a foot ulcer sometime in their lifetimes. Foot ulcers are treatable, however, when they are identified, diagnosed and treated early according to best practice guidelines. Routine follow-up for people with diabetes who may be at risk for neuropathy and/or peripheral vascular disease may prevent subsequent foot ulcers. There are 4 chambers that provide HBOT in Ontario. Fewer than 20 people with DM received HBOT in 2003.
The quality of the evidence assessing the effectiveness of HBOT as an adjunct to standard therapy for people with non-healing diabetic foot ulcers is low, and the results are inconsistent. The results of a recent meta-analysis that found benefit of HBOT to prevent amputation are therefore uncertain. Future well-conducted studies may change the currently published estimates of effectiveness for wound healing and prevention of amputation using HBOT in the treatment of non-healing diabetic foot ulcers.
Although HBOT is an insured service in Ontario, a well conducted, randomized controlled trial that has wound healing and amputation as the primary end-points is needed before this technology is used widely among patients with foot wounds due to diabetes.
PMCID: PMC3382405  PMID: 23074462
14.  A Skin Fixation Method for Decreasing the Influence of Wound Contraction on Wound Healing in a Rat Model 
Archives of Plastic Surgery  2012;39(5):457-462.
The elasticity of the back skin of the rat reduced the tension around wounds during the wound healing process in that region, and thus activates wound contraction. The authors proposed two skin fixation methods using readily available materials to decrease the influence of wound contraction on wound healing and designed an experiment to determine their effects.
The authors made 36 skin wounds on the backs of 18 rats, and they divided them into three groups. Each group was treated with three different kinds of dressing materials, each with different skin fixing characteristics. Group A was a control group. Group B and group C were dressed by the first and the second skin fixation method. We measured the areas of the wounds post-surgically and calculated the wound area reduction rates.
The two skin fixation methods both reduced the effect of wound contraction compared to the control group. Each of the two methods had different outcomes in reducing wound contraction.
The experiment demonstrated significant differences among the wound areas and the wound area reduction rates of the three groups as a result of differences in the degree of wound contraction. To obtain accurate results from wound healing experiments, appropriate skin fixation methods must be adopted.
PMCID: PMC3474401  PMID: 23094239
Wounds and injuries; Wound healing; Rats
15.  Evaluation of Wound Healing Effect of Topical Phenytoin on Excisional Wound in Albino Rats 
Wound healing is a significant healthcare problem in today’s medical practice. Despite extensive treatment modalities that are supposed to hasten the wound healing process, the outcomes of existing methods are far from optimal. One such agent that has been tried previously and found controversial in wound healing is phenytoin. In this study, the wound-healing efficacy of phenytoin was investigated in albino rats.
Materials and Methods:
20 male Wistar albino rats were subjected to excisional wounds measuring 500 mm2 on the back and then randomized to two groups (n = 10): Control group (A) and treatment group (B). The control group received no drug treatment till the end of the study. 1% Phenytoin cream was applied to the wounds of rats in the group B and continued till the 16th day of the study. The areas of wounds were measured on the Days 4, 8, 12, and 16 of the experiment. The percentages of the healing wounds were calculated by Walker formula after measurement of the wound area. The total number of days required for complete epithelization of wounds was noted in each group.
Statistically significant reduction (P < 0.05) in average wound area was seen in Group B (P value=0.0017, 0.0001, 0.0001, 0.0001), respectively, on Days 4, 8, 12, and 16 of the experiment in comparison to Group A. The average number of days required for complete epithelization of wound area was less in Group B as compared to Group A (P=0.0120). The difference was statically significant
In the present study, topical phenytoin accelerated healing of excisional wound in albino rats.
PMCID: PMC3035887  PMID: 21331193
Phenytoin cold cream; area of wound healing; percentage healing of wound area; complete epithelization
In the study of the action of non-antiseptic substances on the rate of cicatrization, the chief obstacle encountered is the facility with which wounds become reinfected under an aseptic dressing. At the beginning of Experiment 1 the wound was sterile. It was subjected to flushing with distilled water for 2 hours, then to flushing with 30 per cent sodium chloride solution for another 2 hours. During that time no special precaution was taken to sterilize the wound and the dressing was left intact until the following morning. It was then found that the wound contained from 30 to 50 bacteria per field. The following day, after the wound had been subjected to the same treatment, the number of bacteria had increased to 50 and 100 per field, and as an immediate consequence the surface of the wound increased from 12 to 12.6 sq. cm. in 2 days. The wound was then dressed antiseptically and was found to be sterile 3 days later. Reinfection again took place the following day in spite of antiseptic dressing with chloramine paste 4 parts per 1,000, which was applied for 20 hours. In Experiment 2 similar results were observed. After 2 days of flushing with distilled water, the number of bacteria had increased to 50 per field. The wound was thereupon sterilized, but new reinfection ensued a few days later. Another wound on the same patient became reinfected under the same conditions after 1 day of sterile dressing. In none of the patients could the wounds be kept in a sterile condition throughout the whole experiment. It was impossible to maintain the sterility of a wound under aseptic dressing. Dakin's solution was therefore injected every 4 hours, or less often, according to the degree of infection, or chloramine paste was applied during the night. If there were 3 or 4 bacteria per field, the experiment was discontinued in order that the wound might be sterilized again. The cicatrization and bacteriological curves of Experiment 4 show that by the application of chloramine paste a wound may be maintained in an appropriately bacteriological condition for carrying out an experiment. Nevertheless, in spite of the antiseptic precautions taken, it was necessary to interrupt this experiment on two occasions, on December 13 to 15 and on December 18 to 22, in order that a complete sterilization of the wound might be effected. When the sterilization was performed as soon as the bacteria were discovered, little retardation occurred in the process of cicatrization. Moreover, the reinfection from the skin was often due to fine bacilli which have but mild retarding action on the rate of healing. The use of at least six flushings in 2 hours with Dakin's solution or of 12 hours' dressing with chloramine paste 10 parts per 1,000, was necessary to keep the wound in a condition of surgical asepsis. The action of distilled water was studied in Experiments 1, 2, and 3. In Experiment 1 the wound was subjected to flushing with distilled water first for 2 hours, then 4 hours, and later for 8 hours per day. The wound was maintained in a condition of mild infection. No marked modification, either acceleration or retardation, was noted in the rate of repair during the period that the treatment was applied. From November 21 to 25 the wound was almost clean and the observed curve remained parallel to the calculated curve, showing that distilled water did not retard the rate of healing. In Experiment 2 the wound was subjected to uninterrupted flushing with distilled water, first for 2 and 8 hours, then for 24 hours. It was continued from November 24 to 30; viz., for 112 hours out of 120, without the occurrence of any marked modification of the course of healing. The bacteriological curve showed that from November 22 to 27 inclusive the wound was kept aseptic. The slight retardation which occurred afterwards was probably brought about by the infection. In Experiment 3 the wound was subjected to flushing with distilled water, first for 2, then for 4, 6, and 8 hours, a total of 20 hours in 4 days. From November 21 to 24 the wound remained surgically aseptic. No modification in the rate of healing occurred. The action of the hypertonic sodium chloride solution was studied in a similar way. In Experiment 4 the wound was flushed at first with 40 per cent sodium chloride solution, from December 4 to 9 for 12 hours a day, and from December 10 to 13 for 24 hours a day, making a total of 144 hours out of 240 hours. At the end of this time the surface area of the wound coincided exactly with the calculated area. Owing to reinfection the experiment was suspended. From December 24 to 29 the wound was kept in contact with 50 per cent sodium chloride solution for 54 hours, and after December 30 flushing with 80 per cent solution for 24 hours a day was resorted to. The total amount of time involved in the above treatments was 174 hours with 40 per cent solution, 72 hours with 50 per cent solution, and 120 hours with 80 per cent solution. On January 1, the surface measured 11 sq. cm. and the calculated surface was 11.3 sq. cm. On January 5 the. surface observed was 10 sq. cm. and the calculated surface was 9 sq. cm. It should be noticed that on January 5 the bacteria numbered 4 per field, which might account for the difference. In Experiment 5 the wound was flushed for 24 hours every day with 50 per cent sodium chloride solution from December 11 to 18, a total of 192 hours. From December 18 to 24 the wound was dressed with agar-agar cakes containing 40 per cent sodium chloride. The concentration was raised to 50 per cent from December 24 to 27. The cicatrization curve indicates only a slight retardation of the repair which can be attributed to infection when both cicatrization and infection curves are compared. The temporary acceleration on the 13th may have been due to the influence of the dressing, but as it did not occur again an experimental error is probably the cause of the change observed in the curve. In Experiment 6 two practically identical wounds at a distance of but a few centimeters from each other were located on the right thigh of Patient 721. The areas of the wounds were respectively 40 and 33 sq. cm. One of the wounds was flushed with distilled water only. The other was subjected to the action of 40 per cent sodium chloride solution. From December 20 to 25 both wounds were in a condition of surgical asepsis. However, the cicatrization curves show that in spite of the difference of treatment the rate of healing was not modified. The rate of healing of the wounds did not therefore apparently undergo any measurable modification under the influence of distilled water or hypertonic salt solution. It is well known that the osmotic changes of the medium have a marked influence on tissues deprived of circulation. But it seems that a tissue with normal circulation is protected by it against the changes of the osmotic pressure occurring at its surface. The above experiments show that apparently the conditions of the tissues of a wound are not modified by the changes of the osmotic pressure of the dressing. The beneficial effects of hypertonic sodium chloride solution on the sterilization of wounds and on the rate of healing recently described by various surgeons are possibly an illusion due to lack of precise technique.
PMCID: PMC2125649  PMID: 19868150
17.  Extended negative pressure wound therapy-assisted dermatotraction for the closure of large open fasciotomy wounds in necrotizing fasciitis patients 
Necrotizing fasciitis (NF) is a rapid progressive infection of the subcutaneous tissue or fascia and may result in large open wounds. The surgical options to cover these wounds are often limited by the patient condition and result in suboptimal functional and cosmetic wound coverage. Dermatotraction can restore the function and appearance of the fasciotomy wound and is less invasive in patients with comorbidities. However, dermatotraction for scarred, stiff NF fasciotomy wounds is often ineffective, resulting in skin necrosis. The authors use extended negative pressure wound therapy (NPWT) as an assist in dermatotraction to close open NF fasciotomy wounds. The authors present the clinical results, followed by a discussion of the clinical basis of extended NPWT-assisted dermatotraction.
A retrospective case series of eight patients with NF who underwent open fasciotomy was approved for the study. After serial wound preparation, dermatotraction was applied in a shoelace manner using elastic vessel loops. Next, the extended NPWT was applied over the wound. The sponge was three times wider than the wound width, and the transparent covering drape almost encircled the anatomical wound area. The negative pressure of the NPWT was set at a continuous 100 mmHg by suction barometer. The clinical outcome was assessed based on wound area reduction after treatment and by the achievement of direct wound closure.
After the first set of extended NPWT-assisted dermatotraction procedures, the mean wound area was significantly decreased (658.12 cm2 to 29.37 cm2; p = 0.002), as five out of eight patients achieved direct wound closure. One patient with a chest wall defect underwent latissimus dorsi musculocutaneous flap coverage, with primary closure of the donor site. Two Fournier’s gangrene patients underwent multiple sets of treatment and finally achieved secondary wound closure with skin grafts. The patients were followed up for 18.3 months on average and showed satisfactory results without wound recurrence.
Extended NPWT-assisted dermatotraction advances scarred, stiff fasciotomy wound margins synergistically in NF and allows direct closure of the wound without complications. This method can be another good treatment option for the NF patient with large open wounds whose general condition is unsuitable for extensive reconstructive surgery.
PMCID: PMC3996171  PMID: 24731449
Necrotizing fasciitis; Negative pressure wound therapy; Dermatotraction; Fournier’s gangrene; Fasciotomy
18.  A Cost-Effective Transparency-Based Digital Imaging for Efficient and Accurate Wound Area Measurement 
PLoS ONE  2012;7(5):e38069.
Wound measurement is an objective and direct way to trace the course of wound healing and to evaluate therapeutic efficacy. Nevertheless, the accuracy and efficiency of the current measurement methods need to be improved. Taking the advantages of reliability of transparency tracing and the accuracy of computer-aided digital imaging, a transparency-based digital imaging approach is established, by which data from 340 wound tracing were collected from 6 experimental groups (8 rats/group) at 8 experimental time points (Day 1, 3, 5, 7, 10, 12, 14 and 16) and orderly archived onto a transparency model sheet. This sheet was scanned and its image was saved in JPG form. Since a set of standard area units from 1 mm2 to 1 cm2 was integrated into the sheet, the tracing areas in JPG image were measured directly, using the “Magnetic lasso tool” in Adobe Photoshop program. The pixel values/PVs of individual outlined regions were obtained and recorded in an average speed of 27 second/region. All PV data were saved in an excel form and their corresponding areas were calculated simultaneously by the formula of Y (PV of the outlined region)/X (PV of standard area unit) × Z (area of standard unit). It took a researcher less than 3 hours to finish area calculation of 340 regions. In contrast, over 3 hours were expended by three skillful researchers to accomplish the above work with traditional transparency-based method. Moreover, unlike the results obtained traditionally, little variation was found among the data calculated by different persons and the standard area units in different sizes and shapes. Given its accurate, reproductive and efficient properties, this transparency-based digital imaging approach would be of significant values in basic wound healing research and clinical practice.
PMCID: PMC3364188  PMID: 22666449
19.  Validation of a Laser-Assisted Wound Measurement Device for Measuring Wound Volume 
Accurate and precise wound measurement is an essential part of the medical record when monitoring a patient with a chronic wound. This study was designed to determine if a new device, a laser-assisted wound measurement (LAWM) device, provides valid measurements for wound area, depth, and volume.
We compared four methods to evaluate the area and volume of 12 wounds of differing size and depth that were created on the dorsum of a sacrificed pig. We evaluated the LAWM device, digital photograph assessment with National Institutes of Health ImageJ software, measurements of depth with a ruler, and weight-to-volume assessment with dental paste. We then sought to cross validate this data with further analyses obtained from these measurements using a Play-Doh®-based wound as a model for constant area with different depths.
We demonstrate that the LAWM device measures wound area accurately. Depth (and therefore volume) measurements, however, are artificially low. This inaccuracy is the same for shallow and deep wounds.
The inaccuracy in the depth and volume measurements with the LAWM device results in an artificially low measurement. However, this may not affect percentage difference measurements. Further studies will need to be performed to determine if this device can accurately determine wound changes in the clinical setting.
J Diabetes Sci Technol 2013;7(4):1161–1166
PMCID: PMC3876358  PMID: 24124941
ARANZ; medical imaging; wound measurement; wound volume
20.  Management of Chronic Pressure Ulcers 
Executive Summary
In April 2008, the Medical Advisory Secretariat began an evidence-based review of the literature concerning pressure ulcers.
Please visit the Medical Advisory Secretariat Web site, to review these titles that are currently available within the Pressure Ulcers series.
Pressure ulcer prevention: an evidence based analysis
The cost-effectiveness of prevention strategies for pressure ulcers in long-term care homes in Ontario: projections of the Ontario Pressure Ulcer Model (field evaluation)
Management of chronic pressure ulcers: an evidence-based analysis
The Medical Advisory Secretariat (MAS) conducted a systematic review on interventions used to treat pressure ulcers in order to answer the following questions:
Do currently available interventions for the treatment of pressure ulcers increase the healing rate of pressure ulcers compared with standard care, a placebo, or other similar interventions?
Within each category of intervention, which one is most effective in promoting the healing of existing pressure ulcers?
A pressure ulcer is a localized injury to the skin and/or underlying tissue usually over a bony prominence, as a result of pressure, or pressure in conjunction with shear and/or friction. Many areas of the body, especially the sacrum and the heel, are prone to the development of pressure ulcers. People with impaired mobility (e.g., stroke or spinal cord injury patients) are most vulnerable to pressure ulcers. Other factors that predispose people to pressure ulcer formation are poor nutrition, poor sensation, urinary and fecal incontinence, and poor overall physical and mental health.
The prevalence of pressure ulcers in Ontario has been estimated to range from a median of 22.1% in community settings to a median of 29.9% in nonacute care facilities. Pressure ulcers have been shown to increase the risk of mortality among geriatric patients by as much as 400%, to increase the frequency and duration of hospitalization, and to decrease the quality of life of affected patients. The cost of treating pressure ulcers has been estimated at approximately $9,000 (Cdn) per patient per month in the community setting. Considering the high prevalence of pressure ulcers in the Ontario health care system, the total cost of treating pressure ulcers is substantial.
Wounds normally heal in 3 phases (inflammatory phase, a proliferative phase of new tissue and matrix formation, and a remodelling phase). However, pressure ulcers often fail to progress past the inflammatory stage. Current practice for treating pressure ulcers includes treating the underlying causes, debridement to remove necrotic tissues and contaminated tissues, dressings to provide a moist wound environment and to manage exudates, devices and frequent turning of patients to provide pressure relief, topical applications of biologic agents, and nutritional support to correct nutritional deficiencies. A variety of adjunctive physical therapies are also in use.
Health technology assessment databases and medical databases were searched from 1996 (Medline), 1980 (EMBASE), and 1982 (CINAHL) systematically up to March 2008 to identify randomized controlled trials (RCTs) on the following treatments of pressure ulcers: cleansing, debridement, dressings, biological therapies, pressure-relieving devices, physical therapies, nutritional therapies, and multidisciplinary wound care teams. Full literature search strategies are reported in appendix 1. English-language studies in previous systematic reviews and studies published since the last systematic review were included if they had more than 10 subjects, were randomized, and provided objective outcome measures on the healing of pressure ulcers. In the absence of RCTs, studies of the highest level of evidence available were included. Studies on wounds other than pressure ulcers and on surgical treatment of pressure ulcers were excluded. A total of 18 systematic reviews, 104 RCTs, and 4 observational studies were included in this review.
Data were extracted from studies using standardized forms. The quality of individual studies was assessed based on adequacy of randomization, concealment of treatment allocation, comparability of groups, blinded assessment, and intention-to-treat analysis. Meta-analysis to estimate the relative risk (RR) or weighted mean difference (WMD) for measures of healing was performed when appropriate. A descriptive synthesis was provided where pooled analysis was not appropriate or not feasible. The quality of the overall evidence on each intervention was assessed using the grading of recommendations assessment, development, and evaluation (GRADE) criteria.
Findings from the analysis of the included studies are summarized below:
There is no good trial evidence to support the use of any particular wound cleansing solution or technique for pressure ulcers.
There was no evidence that debridement using collagenase, dextranomer, cadexomer iodine, or maggots significantly improved complete healing compared with placebo.
There were no statistically significant differences between enzymatic or mechanical debridement agents with the following exceptions:
Papain urea resulted in better debridement than collagenase.
Calcium alginate resulted in a greater reduction in ulcer size compared to dextranomer.
Adding streptokinase/streptodornase to hydrogel resulted in faster debridement.
Maggot debridement resulted in more complete debridement than conventional treatment.
There is limited evidence on the healing effects of debridement devices.
Hydrocolloid dressing was associated with almost three-times more complete healing compared with saline gauze.
There is evidence that hydrogel and hydropolymer may be associated with 50% to 70% more complete healing of pressure ulcers than hydrocolloid dressing.
No statistically significant differences in complete healing were detected among other modern dressings.
There is evidence that polyurethane foam dressings and hydrocellular dressings are more absorbent and easier to remove than hydrocolloid dressings in ulcers with moderate to high exudates.
In deeper ulcers (stage III and IV), the use of alginate with hydrocolloid resulted in significantly greater reduction in the size of the ulcers compared to hydrocolloid alone.
Studies on sustained silver-releasing dressing demonstrated a tendency for reducing the risk of infection and promoting faster healing, but the sample sizes were too small for statistical analysis or for drawing conclusions.
Biological Therapies
The efficacy of platelet-derived growth factors (PDGFs), fibroblast growth factor, and granulocyte-macrophage colony stimulating factor in improving complete healing of chronic pressure ulcers has not been established.
Presently only Regranex, a recombinant PDGF, has been approved by Health Canada and only for treatment of diabetic ulcers in the lower extremities.
A March 2008 US Food and Drug Administration (FDA) communication reported increased deaths from cancers in people given three or more prescriptions for Regranex.
Limited low-quality evidence on skin matrix and engineered skin equivalent suggests a potential role for these products in healing refractory advanced chronic pressure ulcers, but the evidence is insufficient to draw a conclusion.
Adjunctive Physical Therapy
There is evidence that electrical stimulation may result in a significantly greater reduction in the surface area and more complete healing of stage II to IV ulcers compared with sham therapy. No conclusion on the efficacy of electrotherapy can be drawn because of significant statistical heterogeneity, small sample sizes, and methodological flaws.
The efficacy of other adjunctive physical therapies [electromagnetic therapy, low-level laser (LLL) therapy, ultrasound therapy, ultraviolet light therapy, and negative pressure therapy] in improving complete closure of pressure ulcers has not been established.
Nutrition Therapy
Supplementation with 15 grams of hydrolyzed protein 3 times daily did not affect complete healing but resulted in a 2-fold improvement in Pressure Ulcer Scale for Healing (PUSH) score compared with placebo.
Supplementation with 200 mg of zinc three times per day did not have any significant impact on the healing of pressure ulcers compared with a placebo.
Supplementation of 500 mg ascorbic acid twice daily was associated with a significantly greater decrease in the size of the ulcer compared with a placebo but did not have any significant impact on healing when compared with supplementation of 10 mg ascorbic acid three times daily.
A very high protein tube feeding (25% of energy as protein) resulted in a greater reduction in ulcer area in institutionalized tube-fed patients compared with a high protein tube feeding (16% of energy as protein).
Multinutrient supplements that contain zinc, arginine, and vitamin C were associated with a greater reduction in the area of the ulcers compared with standard hospital diet or to a standard supplement without zinc, arginine, or vitamin C.
Firm conclusions cannot be drawn because of methodological flaws and small sample sizes.
Multidisciplinary Wound Care Teams
The only RCT suggests that multidisciplinary wound care teams may significantly improve healing in the acute care setting in 8 weeks and may significantly shorten the length of hospitalization. However, since only an abstract is available, study biases cannot be assessed and no conclusions can be drawn on the quality of this evidence.
PMCID: PMC3377577  PMID: 23074533
21.  Assessment of aortic stenosis by three‐dimensional echocardiography: an accurate and novel approach 
Heart  2007;93(7):801-807.
Accurate assessment of aortic valve area (AVA) is important for clinical decision‐making in patients with aortic valve stenosis (AS). The role of three‐dimensional echocardiography (3D) in the quantitative assessment of AS has not been evaluated so far.
To evaluate the reproducibility and accuracy of real‐time three‐dimensional echocardiography (RT3D) and 3D‐guided two‐dimensional planimetry (3D/2D) for assessment of AS, and compare these results with those of standard echocardiography and cardiac catheterisation (Cath).
AVA was estimated by transthoracic echo‐Doppler (TTE) and by direct planimetry using transoesophageal echocardiography (TEE) as well as RT3D and 3D/2D. 15 patients underwent assessment of AS by Cath.
33 patients with AS were studied (20 men, mean (SD) age 70 (14) years). Bland–Altman analysis showed good agreement and small absolute differences in AVA between all planimetric methods (RT3D vs 3D/2D: −0.01 (0.15) cm2; 3D/2D vs TEE: 0.05 (0.22) cm2; RT3D vs TEE: 0.06 (0.26) cm2). The agreement between AVA assessment by 2D–TTE and planimetry was −0.01 (0.20) cm2 for 3D/2D; 0.00 (0.15) cm2 for RT3D; and −0.05 (0.30) cm2 for TEE. Correlation coefficient r for AVA assessment between each of 3D/2D, RT3D, TEE planimetry and Cath was 0.81, 0.86 and 0.71, respectively. The intraobserver variability was similar for all methods, but interobserver variability was better for 3D techniques than for TEE (p<0.05).
The 3D echo methods for planimetry of the AVA showed good agreement with the standard TEE technique and flow‐derived methods. Compared with AV planimetry by TEE, both 3D methods were at least as good as TEE and had better reproducibility. 3D aortic valve planimetry is a novel non‐invasive technique, which provides an accurate and reliable quantitative assessment of AS.
PMCID: PMC1994466  PMID: 17488766
22.  Effectiveness of bridge V.A.C. dressings in the treatment of diabetic foot ulcers 
Diabetic Foot & Ankle  2011;2:10.3402/dfa.v2i0.5893.
This is a prospective study of the clinical efficacy of the V.A.C. Granufoam Bridge Dressing for the treatment of diabetic foot ulcers.
Materials and methods
Five consecutive patients with diabetic foot ulcers were treated with V.A.C. Granufoam Bridge Dressings and studied over a period of 22–48 days. The indications for treatment included diabetic patients with open ray amputation wounds and wounds post-drainage for abscess with exposed deep structures. Clinical outcome was measured in terms of reduction in wound dimensions, presence of wound granulation, microbial clearance, and development of wound complications.
Our results showed that with V.A.C. therapy, wound healing occurred in all patients. The number of dressings required ranged from 8 to 10. The baseline average wound size was 23.1 cm2. Wound areas shrunk by 18.4–41.7%. All subjects achieved 100% wound bed granulation with an average length of treatment of 33 days. Microbial clearance was achieved in all cases. All wounds healed by secondary intention in one case and four cases required split-thickness skin grafting.
The V.A.C. Granufoam Bridge Dressing is effective in the treatment of diabetic foot ulcers. It promotes reduction of wound area, wound bed granulation, and microbial clearance. By allowing placement of the suction pad outside the foot, it allowed patients to wear protective shoes and to walk non-weight bearing with crutches during V.A.C. therapy.
PMCID: PMC3284286  PMID: 22396825
diabetic foot; negative pressure wound therapy; ulcer; neuropathy
23.  Evaluation of LHP® (1% hydrogen peroxide) cream versus petrolatum and untreated controls in open wounds in healthy horses: a randomized, blinded control study 
Treatment and protection of wounds in horses can be challenging; protecting bandages may be difficult to apply on the proximal extremities and the body. Unprotected wounds carry an increased risk of bacterial contamination and subsequent infection which can lead to delayed wound healing. Topical treatment with antimicrobials is one possibility to prevent bacterial colonization or infection, but the frequent use of antimicrobials ultimately leads to development of bacterial resistance which is an increasing concern in both human and veterinary medicine.
Standardized wounds were created in 10 Standardbred mares. Three wounds were made in each horse. Two wounds were randomly treated with LHP® or petrolatum and the third wound served as untreated control. All wounds were assessed daily until complete epithelization. Protocol data were recorded on day 2, 6, 11, 16, 21 and 28. Data included clinical scores for inflammation and healing, photoplanimetry for calculating wound areas and swab cytology to assess bacterial colonization and inflammation. Bacterial cultures were obtained on day 2, 6 and 16.
Mean time to complete healing for LHP® treated wounds was 32 days (95%CI = 26.9-37.7). Mean time to complete healing for petrolatum and untreated control wounds were 41.6 days (95%CI = 36.2-47.0) and 44.0 days (95%CI = 38.6-49.4) respectively. Wound healing occurred significantly faster in LHP® wounds compared to both petrolatum (p = 0.0004) and untreated controls (p < 0.0001). There was no significant difference in time for healing between petrolatum and untreated controls. Total scores for bacteria and neutrophils were significantly (p < 0.0001) lower for LHP® treated wounds compared to petrolatum from day 16 and onwards. Staphylococcus aureus and Streptococcus zooepidemicus were only found in cultures from petrolatum treated wounds and untreated controls.
Treatment with LHP® reduced bacterial colonization and was associated with earlier complete wound healing. LHP® cream appears to be safe and effective for topical wound treatment or wound protection.
PMCID: PMC3148982  PMID: 21718487
24.  ABC/2 for Rapid Clinical Estimate of Infarct, Perfusion and Mismatch Volumes 
Neurology  2009;72(24):2104-2110.
Rapid and easy clinical assessments for volumes of infarction and perfusion mismatch are needed. We tested whether simple geometrical models generated accurate estimates of these volumes.
Acute diffusion weighted image (DWI) and perfusion (mean transit time, MTT) in 63 strokes and established infarct volumes in 50 subacute strokes were measured by computerized planimetry. Mismatch was defined as (MTT-DWI)/DWI ≥ 0.2. Observers, blinded to planimetric values, measured lesions in three perpendicular axes A, B and C. Geometrical estimates of sphere, ellipsoid, bicone and cylinder were compared to planimetric volume by least-squares linear regression.
The ABC/2 formula (ellipsoid) was superior to other geometries for estimating volume of DWI (slope 1.16 95% confidence interval (95%CI) 0.94 to 1.38; R2 = .91, p=0.001) and MTT (slope 1.11, 95%CI 0.99 to 1.23; R2 = .89, p=0.001). The intra-rater and inter-rater reliability for ABC/2 was high for both DWI (.992 and .965) and MTT (.881 and .712). For subacute infarct, the ABC/2 formula also best estimated planimetric volume (slope 1.00, 95%CI 0.98 to 1.19; R2 = .74, p=0.001). In general, sphere and cylinder geometries overestimated all volumes and bicone underestimated all volumes. The positive predictive value for mismatch was 92% and negative predictive value was 33%
Of the models tested, ABC/2 is reproducible, accurate and provides the best simple geometric estimate of infarction and MTT volumes. ABC/2 has a high positive predictive value for identifying mismatch greater than 20% and might be a useful tool for rapid determination of acute stroke treatment.
PMCID: PMC2697964  PMID: 19528517
Cerebrovascular Accident; Infarction; Estimation Techniques; Computed Tomography Scanners; Magnetic Resonance Imaging
25.  ABC/2 for rapid clinical estimate of infarct, perfusion, and mismatch volumes 
Neurology  2009;72(24):2104-2110.
Rapid and easy clinical assessments for volumes of infarction and perfusion mismatch are needed. We tested whether simple geometric models generated accurate estimates of these volumes.
Acute diffusion-weighted image (DWI) and perfusion (mean transit time [MTT]) in 63 strokes and established infarct volumes in 50 subacute strokes were measured by computerized planimetry. Mismatch was defined as MTT/DWI ≥ 1.2. Observers, blinded to planimetric values, measured lesions in three perpendicular axes A, B, and C. Geometric estimates of sphere, ellipsoid, bicone, and cylinder were compared to planimetric volume by least-squares linear regression.
The ABC/2 formula (ellipsoid) was superior to other geometries for estimating volume of DWI (slope 1.16, 95% confidence interval [CI] 0.94 to 1.38; R2 = 0.91, p = 0.001) and MTT (slope 1.11, 95% CI 0.99 to 1.23; R2 = 0.89, p = 0.001). The intrarater and interrater reliability for ABC/2 was high for both DWI (0.992 and 0.965) and MTT (0.881 and 0.712). For subacute infarct, the ABC/2 formula also best estimated planimetric volume (slope 1.00, 95% CI 0.98 to 1.19; R2 = 0.74, p = 0.001). In general, sphere and cylinder geometries overestimated all volumes and bicone underestimated all volumes. The positive predictive value for mismatch was 92% and negative predictive value was 33%.
Of the models tested, ABC/2 is reproducible, is accurate, and provides the best simple geometric estimate of infarction and mean transit time volumes. ABC/2 has a high positive predictive value for identifying mismatch greater than 20% and might be a useful tool for rapid determination of acute stroke treatment.
= cerebral blood flow;
= cerebral blood volume;
= confidence interval;
= diffusion-weighted image;
= field of view;
= intracerebral hemorrhage;
= middle cerebral artery;
= mean transit time;
= perfusion-weighted imaging;
= region of interest;
= echo time;
= repetition time.
PMCID: PMC2697964  PMID: 19528517

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