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1.  Ulcerated Radiodermatitis Induced after Fluoroscopically Guided Stent Implantation Angioplasty 
Cases of radiation-induced skin injury after fluoroscopically guided procedures have been reported since 1996, though the majority of them have been published in Radiology and Cardiology literature, less frequently in Dermatology journals. Chronic radiation dermatitis induced by fluoroscopy can be difficult to diagnose; a high grade of suspicion is required. We report a case of an obese 46-year-old man with hypertension, dyslipidemia, and severe coronary artery disease. He developed a pruritic and painful atrophic ulcerated skin plaque over his left scapula, six months after fluoroscopically guided stent implantation angioplasty. The diagnosis of radiodermatitis was confirmed histologically. We report this case to emphasize the importance of recognizing fluoroscopy as a cause of radiation dermatitis. A good clinical follow-up at regular intervals is important after long and complicated procedures, since the most prevalent factor for injury is long exposure time.
PMCID: PMC4168146  PMID: 25276441
2.  Supplementation of bone marrow aspirate-derived platelet-rich plasma for treating radiation-induced ulcer after cardiac fluoroscopic procedures: A preliminary report 
The frequency of encountering radiodermatitis caused by X-ray fluoroscopic procedures for ischaemic heart disease is increasing. In severe cases, devastating ulcers with pain, for which conservative therapy is ineffective, emerge. Radiation-induced ulcers are notorious for being difficult to treat. Simple skin grafting often fails because of the poor state of the wound bed. A vascularized flap is a very good option. However, the non-adherence of the well-vascularized flap with the irradiated wound bed is frequently experienced.
To ameliorate the irradiated wound bed, bone marrow-derived platelet-rich plasma (bm-PRP) was delivered during the surgery.
Materials and Methods:
Four patients with severe cutaneous radiation injury accompanied by unbearable pain after multiple fluoroscopic procedures for ischaemic heart disease were treated. Wide excision of the lesion and coverage with a skin flap supplemented with bm-PRP injection was performed.
All patients obtained wound closure and were relieved from pain. No complication concerning the bone marrow aspiration and delivery of bm-PRP was observed.
Supplementation of bm-PRP can be an option without major complications, time, and cost to improve the surgical outcome for irradiated wounds.
PMCID: PMC3385373  PMID: 22754164
Bone marrow; cardiac fluoroscopy; platelet-rich plasma; radiation ulcer; skin flap
3.  IL-1 Generated Subsequent to Radiation-Induced Tissue Injury Contributes to the Pathogenesis of Radiodermatitis 
Radiation research  2012;178(3):166-172.
Radiation injury in the skin causes radiodermatitis, a condition in which the skin becomes inflamed and the epidermis can break down. This condition causes significant morbidity and if severe it can be an independent factor that contributes to radiation mortality. Radiodermatitis is seen in some settings of radiotherapy for cancer and is also of concern as a complication post-radiation exposure from accidents or weapons, such as a “dirty bomb”. The pathogenesis of this condition is incompletely understood. Here we have developed a murine model of radiodermatitis wherein the skin is selectively injured by irradiation with high-energy electrons. Using this model we showed that the interleukin-1 (IL-1) pathway plays a significant role in the development of radiodermatitis. Mice that lack either IL-1 or the IL-1 receptor developed less inflammation and less severe pathological changes in their skin, especially at later time-points. These findings suggest that IL-1 pathway may be a potential therapeutic target for reducing the severity of radiodermatitis.
PMCID: PMC3483593  PMID: 22856653
4.  Phototherapy 660 nm for the prevention of radiodermatitis in breast cancer patients receiving radiation therapy: study protocol for a randomized controlled trial 
Trials  2014;15(1):330.
Breast neoplasms are the second most common type of cancer worldwide, and radiation therapy is a key component of their treatment. Acute skin reactions are one of the most common side effects of radiation therapy, and prevention of this adverse event has been investigated in several studies. However, a clinically applicable, preventative treatment remains unavailable. It has been demonstrated that application of a low-power laser can promote tissue repair. Therefore, the aim of this trial is to evaluate the effectiveness of an indium gallium aluminum phosphorus (InGaAIP) laser operated at 660 nm in preventing radiodermatitis in women undergoing adjuvant radiotherapy for breast cancer.
This is a two-arm, randomized controlled trial. A total of 52 patients undergoing radiotherapy for breast cancer (stages I to III) will be enrolled. Patients will be randomly assigned to an intervention group to receive laser therapy (n = 26) or a control group to receive a placebo (n = 26). The laser or placebo will be applied five days a week, immediately before each radiotherapy session. Skin reactions will then be graded weekly by a nurse, a radiotherapist, and an oncologist (all of whom will be blinded) using the Common Toxicity Criteria (CTC) developed by the National Cancer Institute and the Acute Radiation Morbidity Scoring Criteria developed by the Radiation Therapy Oncology Group. Patients will also answer a modified visual analogue scale for pain (a self-evaluation questionnaire). Primary and secondary outcomes will be the prevention of radiodermatitis and pain secondary to radiodermatitis, respectively.
The ideal tool for preventing radiodermatitis is an agent that mediates DNA repair or promotes cell proliferation. Application of a low-power laser has been shown to promote tissue repair by reducing inflammation and inducing collagen synthesis. Moreover, this treatment approach has not been associated with adverse events and is cost-effective. Thus, the results of this ongoing trial may establish whether use of a low-power laser represents an ideal treatment option for the prevention of radiodermatitis.
Trial registration identifier: NCT02003599. Registered on 2 December 2013.
PMCID: PMC4148541  PMID: 25141962
Breast neoplasms; Laser therapy; Low-level; Radiodermatitis; Prevention & control
5.  Thermal boost combined with interstitial brachytherapy in breast conserving therapy – Assessment of early toxicity 
Hyperthermia (HT) causes a direct damage to cancerous cells and/or sensitize them to radiotherapy with usually minimal injury to normal tissues. Adjuvant HT is probably one of the most effective radiation sensitizers known and works best when delivered simultaneously with radiation. In breast conserving therapy, irradiation has to minimize the risk of local relapse within the treated breast, especially in an area of a tumor bed. Brachytherapy boost reduces 5-year local recurrence rate to mean 5,5%, so there still some place for further improvement. The investigated therapeutic option is an adjuvant single session of local HT (thermal boost) preceding standard CT-based multicatheter interstitial HDR brachytherapy boost in order to increase the probability of local cure.
To report the short-term results in regard to early toxicity of high-dose-rate (HDR) brachytherapy (BT) boost with or without interstitial microwave hyperthermia (MV HT) for early breast cancer patients treated with breast conserving therapy (BCT).
Materials and methods
Between February 2006 and December 2007, 57 stage IA–IIIA breast cancer patients received a 10 Gy HDR BT boost after conservative surgery and 42.5–50 Gy whole breast irradiation (WBI) ± adjuvant chemotherapy. 32 patients (56.1%) were treated with additional pre-BT single session of interstitial MW HT to a tumor bed (multi-catheter technique). Reference temperature was 43 °C and therapeutic time (TT) was 1 h. Incidence, severity and duration of radiodermatitis, skin oedema and skin erythema in groups with (I) or without HT (II) were assessed, significant p-value ≤ 0.05.
Median follow-up was 40 months. Local control was 100% and distant metastasis free survival was 91.1%. HT sessions (median): reference temperature 42.2 °C, therapeutic time (TT) 61.4 min, total thermal dose 42 min and a gap between HT and BT 30 min. Radiodermatitis grades I and II occurred in 24 and 6 patients, respectively, differences between groups I and II were not significant. Skin oedema and erythema occurred in 48 (85.7%) and 36 (64.3%) cases, respectively, and were equally distributed between the groups. The incidence and duration of skin oedema differed between the subgroups treated with different fractionation protocols of WBI, p = 0.006. Skin oedema was present up to 12 months. No difference in pattern of oedema regression between groups I and II was observed, p = 0.933.
Additional thermal boost preceding standard HDR BT boost has a potential of further improvement in breast cancer local control in BCT. Pre-BT hyperthermia did not increase early toxicity in patients treated with BCT and was well tolerated. All side effects of combined treatment were transient and were present for up to 12 months. The increase in incidence of skin oedema was related to hypofractionated protocols of WBI. The study has to be randomized and continued on a larger group of breast cancer patients to verify the potential of local control improvement and to assess the profile of late toxicity.
PMCID: PMC3863141  PMID: 24376963
Hyperthermia; Brachytherapy boost; Breast cancer
6.  Squamous cell carcinoma of the nipple following radiation therapy for ductal carcinoma in situ: a case report 
Radiation-induced nonmelanoma skin cancer was first reported seven years after the discovery of X-rays, but has received relatively little consideration in the literature. Specifically, nonmelanoma skin cancer after conservative surgery and radiation for early stage breast cancer has not been well studied. We report the case of a woman who developed squamous cell carcinoma of the nipple nine years after conservative surgery and radiation for ductal carcinoma in situ of the ipsilateral breast. We also review the relevant literature available to date.
Case presentation
A 66-year-old African-American woman presented to the hospital with a non-healing ulcer of the right nipple. Her past medical history was significant for right breast ductal carcinoma in situ for which she had undergone lumpectomy and whole breast radiation therapy nine years previously. Mammography and magnetic resonance imaging studies were negative for recurrent breast cancer. However, the latter demonstrated abnormal enhancement in the nipple-areolar region. An incisional biopsy of the lesion demonstrated invasive squamous cell carcinoma. Subsequently, the patient underwent wide excision of the nipple-areolar complex. Sentinel lymph-node biopsy was offered but our patient declined. She was considered to have local disease and hence no further treatment was recommended.
This case represents the first reported occurrence of squamous cell carcinoma of the nipple to follow conservative surgery and radiation for ductal carcinoma in situ of the ipsilateral breast. It is likely that radiation overexposure resulted in a radiation burn and subsequent radiodermatitis, placing it at risk for squamous cell carcinoma. A diagnosis of squamous cell carcinoma should be considered in a patient with a nipple lesion following radiation therapy for breast cancer.
PMCID: PMC2907399  PMID: 20565942
7.  The Radiation Issue in Cardiology: the time for action is now 
The "radiation issue" is the need to consider possible deterministic effects (e.g., skin injuries) and long-term cancer risks due to ionizing radiation in the risk-benefit assessment of diagnostic or therapeutic testing. Although there are currently no data showing that high-dose medical studies have actually increased the incidence of cancer, the "linear-no threshold" model in radioprotection assumes that no safe dose exists; all doses add up in determining cancer risks; and the risk increases linearly with increasing radiation dose. The possibility of deterministic effects should also be considered when skin or lens doses may be over the threshold. Cardiologists have a special mission to avoid unjustified or non-optimized use of radiation, since they are responsible for 45% of the entire cumulative effective dose of 3.0 mSv (similar to the radiological risk of 150 chest x-rays) per head per year to the US population from all medical sources except radiotherapy. In addition, interventional cardiologists have an exposure per head per year two to three times higher than that of radiologists. The most active and experienced interventional cardiologists in high volume cath labs have an annual exposure equivalent to around 5 mSv per head and a professional lifetime attributable to excess cancer risk on the order of magnitude of 1 in 100. Cardiologists are the contemporary radiologists but sometimes imperfectly aware of the radiological dose of the examination they prescribe or practice, which can range from the equivalent of 1-60 mSv around a reference dose average of 10-15 mSv for a percutaneous coronary intervention, a cardiac radiofrequency ablation, a multi-detector coronary angiography, or a myocardial perfusion imaging scintigraphy. A good cardiologist cannot be afraid of life-saving radiation, but must be afraid of radiation unawareness and negligence.
PMCID: PMC3256101  PMID: 22104562
cancer; cardiology; imaging; risk
8.  Provision of services for the diagnosis and treatment of heart disease. Fourth report of a Joint Cardiology Committee of the Royal College of Physicians of London and the Royal College of Surgeons of England. 
British Heart Journal  1992;67(1):106-116.
The principal conclusions of the fourth report of the Joint Cardiology Committee are: 1 Cardiovascular disease remains a major cause of death and morbidity in the population and of utilisation of medical services. 2 Reduction in the risk of cardiovascular disease is feasible, and better co-ordination is required of strategies most likely to be effective. 3 Pre-hospital care of cardiac emergencies, in particular the provision of facilities for defibrillation, should continue to be developed. 4 There remains a large shortfall in provision of cardiological services with almost one in five district hospitals in England and Wales having no physician with the appropriate training. Few of the larger districts have two cardiologists to meet the recommendation for populations of over 250,000. One hundred and fifty extra consultant posts (in both district and regional centres) together with adequate supporting staff and facilities are urgently needed to provide modest cover for existing requirements. 5 The provision of coronary bypass grafting has expanded since 1985, but few regions have fulfilled the unambitious objectives stated in the Third Joint Cardiology Report. 6 The development of coronary angioplasty has been slow and haphazard. All regional centres should have at least two cardiologists trained in coronary angioplasty and there should be a designated budget. Surgical cover is still required for most procedures and is best provided on site. 7 Advances in the management of arrhythmias, including the use of specialised pacemakers, implantable defibrillators, and percutaneous or surgical ablation of parts of the cardiac conducting system have resulted in great benefit to patients. Planned development of the emerging sub-specialty of arrhythmology is required. 8 Strategies must be developed to limit the increased exposure of cardiologists to ionising radiation which will result from the expansion and increasing complexity of interventional procedures. 9 Supra-regional funding for infant cardiac surgery and transplantation has been successful and should be continued. 10 Despite advances in non-invasive diagnosis of congenital heart disease the amount of cardiac catheterisation of children has risen due to the increase in number of interventional procedures. Vacant consultant posts in paediatric cardiology and the need for an increase in the number of such posts cannot be filled from existing senior registrar posts. All paediatric cardiac units should have a senior registrar and in the meantime it may be necessary to make proleptic appointments to consultant posts with arrangements for the appointees to complete their training. 11 Provision of care for the increasing number of adolescent and adult survivors of complex congenital heart disease is urgently required. The management of these patients is specialised, and the committee recommends that it should ultimately be undertaken by either adult or pediatric cardiologists with appropriate additional training working in supra-regionally funded centers alongside specially trained surgeons. 12 Cardiac rehabilitation should be available to all patients in the United Kingdom. 13 New recommendations for training in cardiology are for a total of at least five years in the specialty after general professional training, plus a year as senior registrar in general medicine. An additional year may be required for those wishing to work in interventional cardiology and adequate provision must be made for those with an academic interest. 14 It is essential that both basic and clinical research is carried out in cardiac centres but these activities are becoming increasingly limited by the lack of properly funded posts in the basic sciences and restriction in the number of honorary posts for clinical research workers. 15 A joint audit committee of the Royal College of Physicians and the British Cardiac Society has been established to coordinate audit in the specialty. All district and regional cardiac centres should cooperate with the work of the committee, in addition to their participation in local audit activities.
PMCID: PMC1024713  PMID: 1739519
9.  Protective effect of inhalation of hydrogen gas on radiation-induced dermatitis and skin injury in rats 
Journal of Radiation Research  2014;55(6):1107-1113.
The effect of inhalation of hydrogen-containing gas (1.3% hydrogen + 20.8% oxygen + 77.9% nitrogen) (HCG) on radiation-induced dermatitis and on the healing of healing-impaired skin wounds in rats was examined using a rat model of radiation-induced skin injury. An X-ray dose of 20 Gy was irradiated onto the lower part of the back through two holes in a lead shield. Irradiation was performed before or after inhalation of HCG for 2 h. Inhalation of HCG significantly reduced the severity of radiodermatitis and accelerated healing-impaired wound repair. Staining with terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) showed that the proportion of apoptotic keratinocytes and the level of staining in the X-irradiated skin of rats that pre-inhaled HCG were significantly lower than that of rats which did not pre-inhale HCG. Cutaneous full-thickness wounds were then created in the X-irradiated area to examine the time-course of wound healing. X-irradiation significantly increased the time required for wound healing, but the inhalation of HCG prior to the irradiation significantly decreased the delay in wound healing compared with the control and post-inhalation of HCG groups. Therefore, radiation-induced skin injury can potentially be alleviated by the pre-inhalation of HCG.
PMCID: PMC4229932  PMID: 25034733
radioprotection; hydrogen; radiodermatitis; healing-impaired wound; antioxidant
10.  Incidence and Risk Factors of the Secondary Skin Infections in Patients with Radiodermatitis 
The Eurasian Journal of Medicine  2011;43(3):177-181.
The aim of this prospective study was to investigate the incidence and risk factors of secondary infected radiodermatitis in patients receiving radiotherapy and to determine isolated microorganisms’ resistance profiles to different antimicrobial agents.
Materials and Methods:
The study comprised 62 patients admitted to the Regional Training and Research Hospital from January 2009 to January 2010. Radiodermatitis was graded according to the National Cancer Institute’s Common Toxicity Criteria version 3.0. Potential risk factors for secondary infection were recorded and evaluated by univariate and multivariate analyses.
In 62 patients, grade 1, 2, 3 and 4 radiodermatitis were observed in 33 (53.2%), 11 (17.7%), 8 (12.9%) and 10 (16.2%) patients, respectively. Skin infection secondary to radiodermatitis occurred in 14 patients (infected patients), 21.4%, 21.4% and 57.2% of whom had grade 2, 3 and 4 radiodermatitis, respectively. Forty-eight patients were found to be colonized with micoorganisms (colonized patients). In the univariate analysis, concurrent endocrine therapy and radiodermatitis grade differed significantly between infected and colonized patients (p<0.05). Multivariate analyses showed that the radiodermatitis grade was an independent risk factor for the acquisition of infection (p<0.05). The microbial pathogens isolated from patients with skin infection were seven methicillin-resistant coagulase-negative Staphylococcus (MRCNS) strains, three methicillin-resistant Staphylococcus aureus (MRSA) strains, two Candida sp., one methicillin-sensitive coagulase-negative Staphylococcus (MSCNS) strain and one methicillin-sensitive S. aureus (MSSA) strain. Staphylococci strains were more resistant to beta-lactam antibiotics. No glycopeptide resistance was found.
The results of this study indicate that high-grade radiodermatitis leads to an increased risk for secondary infection of the skin with pathogens.
PMCID: PMC4261391  PMID: 25610188
Colonization; Radiodermatitis; Risk factors; Secondary skin infection
11.  ROS-Scavenger and Radioprotective Efficacy of the New PrC-210 Aminothiol 
Radiation research  2012;178(1):57-68.
To identify new aminothiol radioprotectors that are active when applied topically and have fewer side effects when administered systemically, a new family of aminothiol radioprotectors was designed and synthesized. Three key elements in the aminothiol design were, (1) small size for efficient transmembrane diffusion, (2) positive charged amines in alkyl backbone for strong ionic interaction with DNA backbone, and (3) a perpendicular, alkyl side-chain with a terminal thiol that is projected away from the DNA backbone to enable reactive oxygen species scavenging around DNA. Several in vitro assays were used to characterize the prototype aminothiol, PrC-210, for efficacy: protection against reactive oxygen species-induced plasmid DNA nicking, mass spectrometry to detect aminothiol-reactive oxygen species by-products, S. typhimurium mutagenesis, human cell growth inhibition, Western blot for p21 expression, and FACS analysis. Additionally, two in vivo assays were used to assess radioprotective efficacy; a Sprague-Dawley rat dorsal skin radiodermatitis assay was developed to screen for aminothiol efficacy when topically applied, and ICR mouse survival was scored after systemic PrC-210 administration and whole-body radiation. PrC-210 efficiently scavenged reactive oxygen species and completely protected supercoiled plasmid DNA against reactive oxygen species-induced damage. Neither PrC-210 nor its analog PrC-211 were bacterial mutagens. In cell culture, PrC-210 application to diploid human fibroblasts showed: (1) inhibition of cell growth with an IC70 of 4.1 mM, (2) induced levels of p21 expression, and (3) a G1/S-cell cycle block that was reversed after washout of PrC-210-containing medium. In rodents, PrC-210 was an effective radioprotector showing: (1) complete prevention of Grade 2–3 radiodermatitis when applied topically (370 mM in ethanol:propylene glycol:water solution) prior to skin irradiation, (2) complete prevention of Grade 2–3 radioder-matitis when administered by i.p. injection (200 μg/g of body weight) before skin irradiation, (3) 100% survival of mice from an otherwise 100% lethal dose of whole-body radiation (8.75 Gy) when administered by i.p. injection (252 μg/g of body weight = 0.5 × maximum tolerated dose) before irradiation, and (4) a dose reduction factor of 1.6, the same as amifostine. These data suggest that the PrC-210 aminothiol is a plausible candidate for drug development as a human pre-exposure radioprotector.
PMCID: PMC3409661  PMID: 22702647
12.  The Principle of Digital Subtraction Angiography and Radiological Protection 
Interventional Neuroradiology  2001;6(Suppl 1):25-31.
Recent improvements in x-ray technology have greatly contributed to the advancement of diagnostic imaging. Fluoroscopically guided neurointerventional procedures with digital subtraction angiography (DSΛ) are being performed with increasing frequency as the treatment of choice for a variety of neurovascular diseases. Radiation-induced skin injuries can occur after extended fluoroscopic exposure times, and the injuries have recently been reported. In this article, measured radiation doses at the surface of Rando Phantom with Skin Dose Monitor, and estimated and measured entrance skin doses in patients underwent neurointerventional procedures are reported as well as means of reducing radiation doses absorbed by patients and personnel to avoid occurrence of radiation-induced injuries.
PMCID: PMC3685929  PMID: 20667218
fluoroscopically guided interventional procedure, digital subtraction angiography, radiation protection
13.  Diagnostic cardiac catheterisation in a hospital without on-site cardiac surgery 
Heart  1999;81(5):465-469.
OBJECTIVE—To assess the feasibility, safety, and clinical impact of diagnostic cardiac catheterisation in a multipurpose laboratory in a district general hospital without cardiac surgery.
METHODS—A prospective audit of the first 2000 consecutive cases between September 1992 and March 1997. Unstable patients were referred to a surgical centre for investigation, in line with subsequently published British Cardiac Society (BCS) guidelines, but all other patients requiring cardiac catheterisation were investigated locally and are included in this report. The function of the laboratory was also compatible with the BCS guidelines regarding staffing, operators, equipment, number of cases, and locally available vascular surgery.
RESULTS—Of the 2000 cases, 1988 studies were completed (99%), 1985 (99%) included coronary angiography, and 1798 (90%) were performed as day cases. Left main stem disease was present in 157 (8%), three vessel disease in 683 (34%), two vessel disease in 387 (19%), single vessel disease in 424 (21%), and normal coronary arteries in 494 (25%). Of the latter, 284 (14% of the total) had another cardiac diagnosis for which they were investigated (for example, valvar heart disease). Referral for cardiac intervention following catheterisation was made in 1172 of the 2000 cases (intervention rate 59%; catheter:intervention ratio 1.7:1). The interventions performed were coronary artery bypass grafting (CABG) in 736 of the 1172 cases (63%), other types of cardiac surgery in 122 (10%), combined CABG and other cardiac surgery in 71 (6%), and percutaneous transluminal coronary angioplasty in 243 (21%). There were two catheter related deaths (0.1%), both of which occurred within 24 hours of the procedure, and a further nine major cardiovascular complications with residual morbidity (0.45%). These were myocardial infarction in two (0.1%), cerebrovascular events in two (0.1%), and surgical vascular complications in five (0.25%). In addition, there were eight successfully treated, life threatening arrhythmias (0.4%).
CONCLUSIONS—Diagnostic cardiac catheterisation can be performed safely and successfully in a local hospital. When BCS guidelines are followed, the mortality is similar to published pooled data from regional centres (0.1% v 0.12%). The high intervention rate indicates a persistent unmet demand in the districts, which will continue to affect surgical and interventional services.

Keywords: cardiac catheterisation; audit; district general hospital; coronary artery disease
PMCID: PMC1729033  PMID: 10212162
14.  Practical Protective Tools for Occupational Exposure: 
Interventional Neuroradiology  2001;6(Suppl 1):33-42.
Two practical protective tools for occupational exposure for neurointerventional radiologists are presented. The first purpose of this study was to investigate the effectiveness of double focus spectacles for the aged with a highly refracted glass lens (special spectacles for the aged) for radiation protection of the crystalline lens of the eye in comparison with other spectacles on the market, based on the measurement of film density which was obtained by exposure of X-ray through those spectacles. As a result of the film densitometry mentioned above, the effectiveness of special spectacles for the aged in radiation protection was nearly equal to the effectiveness of a goggle type shield which is made with a 0.07 mm lead-equivalent plastic lens.
The second purpose of this study was to investigate the effectiveness of the protective barrier; which we remodeled for cerebral angiography or neuroendovascular therapy, for radiation exposure, based on the measurement in a simulated study with a head phantom, and on the measurement of radiation exposure in operaters during procedures of clinical cases. In the experimental study radiation exposure in supposed position of the crystalline lens was reduced to about one third and radiation exposure in supposed position of the gonadal glands was reduced to about one seventh, compared to radiation exposure without employing the barrier.
The radiation exposure was monitored at the left breast of three radiologists, in 215 cases of cerebral angiography. Employing the barrier in cerebral angiography, average equivalent dose at the left breast measured 1.49µ Sv during 10 min of fluoroscopy. In three kinds of neuroendovascular therapy in 40 cases, radiation exposure in an operator was monitored in the same fashion and the dose was recorded less than the result reported in previous papers in which any protective barrier have not been employed in the procedure1,2.
As a result, the two above mentioned protective tools are considered practical in clinical usage and very effective to reduce radiation exposure in an operator of interventional neuroradiolgy which may sometimes require many hours to complete the therapy under extended fluoroscopic time.
PMCID: PMC3685933  PMID: 20667219
occupational exposure, radiation protection, crystalline lens of eye, barrier against X-ray exposure, cerebral angiography, interventional neuroradiology
15.  Cancer risks following diagnostic and therapeutic radiation exposure in children 
Pediatric Radiology  2006;36(Suppl 2):121-125.
The growing use of interventional and fluoroscopic imaging in children represents a tremendous benefit for the diagnosis and treatment of benign conditions. Along with the increasing use and complexity of these procedures comes concern about the cancer risk associated with ionizing radiation exposure to children. Children are considerably more sensitive to the carcinogenic effects of ionizing radiation than adults, and children have a longer life expectancy in which to express risk. Numerous epidemiologic cohort studies of childhood exposure to radiation for treatment of benign diseases have demonstrated radiation-related risks of cancer of the thyroid, breast, brain and skin, as well as leukemia. Many fewer studies have evaluated cancer risk following diagnostic radiation exposure in children. Although radiation dose for a single procedure might be low, pediatric patients often receive repeated examinations over time to evaluate their conditions, which could result in relatively high cumulative doses. Several cohort studies of girls and young women subjected to multiple diagnostic radiation exposures have been informative about increased mortality from breast cancer with increasing radiation dose, and case-control studies of childhood leukemia and postnatal diagnostic radiation exposure have suggested increased risks with an increasing number of examinations. Only two long-term follow-up studies of cancer following cardiac catheterization in childhood have been conducted, and neither reported an overall increased risk of cancer. Most cancers can be induced by radiation, and a linear dose-response has been noted for most solid cancers. Risks of radiation-related cancer are greatest for those exposed early in life, and these risks appear to persist throughout life.
PMCID: PMC2663653  PMID: 16862418
Radiation risks; Carcinogenesis; Diagnostic radiation; Therapeutic radiation
16.  Radiation port wart: a distinct cutaneous lesion after radiotherapy. 
LABELED BACKGROUND: Radiotherapy may cause common cutaneous side effects such as acute and chronic radiodermatitis and also rare skin conditions. CASE REPORT: A 42-year-old woman who received radiotherapy for invasive breast carcinoma developed multiple, scaly, rough papules and nodules restricted to treatment fields six months after completion of the treatment. A relapse of the breast cancer and/or seborrheic keratosis was ruled out by histological confirmation of verruca vulgaris. CONCLUSION: We report the first case of verruca vulgaris associated with radiation treatment. Radiotherapists and dermatologists should be aware of this possibility and be able to differentiate it from other skin lesions associated with irradiation.
PMCID: PMC2569464  PMID: 16895295
17.  Comparing radiation exposure during percutaneous vertebroplasty using one- vs. two-fluoroscopic technique 
Percutaneous vertebroplasty (PV) requires relatively lengthy fluoroscopic guidance, which might lead to substantial radiation exposure to patients or operators. The two-fluoroscopic technique (two-plane radiographs obtained using two fluoroscopes) during PV can provide simultaneous two-planar projections with reducing operative time. However, the two-fluoroscopic technique may expose the operator or patient to increased radiation dose. The aim of this study was to quantify the amount of radiation exposure to the patient or operator that occurs during PV using one- vs. two-fluoroscopic technique.
Two radiation dosimeters were placed on the right flank of each patient and on the upper sternum of each operator during 26 single-level PV procedures by one senior surgeon. The use of two-fluoroscopic technique (13 patients) and one-fluoroscopic technique (13 patients) were allocated in a consecutive and alternative manner. The operative time and mean radiation dose to each patient and operator were monitored and compared between groups.
Mean radiation dose to the patient was 1.97 ± 1.20 mSv (95% CI, 0.71 to 3.23) for the one-fluoroscopic technique group vs. 0.95 ± 0.34 mSv (95% CI, 0.85 to 1.23) for the two-fluoroscopic technique group (P =0.031). Mean radiation dose to the operator was 0.27 ± 0.12 mSv (95% CI, 0.17–0.56) for the one-fluoroscopic technique group vs. 0.25 ± 0.14 mSv (95% CI, 0.06–0.44) for the two-fluoroscopic technique group (P = 0.653). The operative time was significantly different between groups: 47.15 ± 13.48 min (range, 20–75) for the one-fluoroscopic technique group vs. 36.62 ± 8.42 min (range, 21–50) for the two-fluoroscopic technique group (P =0.019).
Compared to the one-fluoroscopic technique, the two-fluoroscopic technique used during PV provides not only shorter operative times but also reduces the radiation exposure to the patient. There was no significant difference between the two techniques with regards to radiation exposure to the operator.
PMCID: PMC3557160  PMID: 23339360
Vertebral compression fracture; Osteoporosis; Vertebroplasty; Radiation dose
18.  Anesthesia for cardiac catheterization procedures 
Heart, Lung and Vessels  2014;6(4):225-231.
Anesthesiologist’s involvement for the purpose of diagnostic and interventional procedures in cardiac catheterization laboratory has been evolving particularly since last two decades. Catheterization laboratory environment poses certain challenges for the anesthesiologist including unfamiliar remote location, exposure to radiation, limited help from colleagues and communication with cardiologists. Anesthesiologists working in catheterization laboratory are required to have adequate knowledge of the environment, personnel, fluoroscope, echocardiography and type of radio contrast dye during the procedure. Anyone who is exposed to radiation environment is expected to protect himself from the exposure and must also wear a dosimeter for cumulative exposure tracing. There is no ideal anesthetic technique and the decision about sedation, general anesthesia or regional anesthesia for the procedure has to be made by attending anesthesiologists in consultation with cardiologists. Anesthesiologists should always try to minimize the effects of anesthesia on cardiovascular system. In addition, oxygenation and ventilatory management should be done according to the diagnostic procedure as it can also influence the diagnosis particularly in pediatric cath procedures. Since more complex procedures are being done in cardiac catheterization laboratory,  it is the responsibility of anesthesia department to train and assign dedicated anesthesiologists for new challenges. Role of anesthetist should be well defined so that there is no confrontation during patient management. Sedation in cardiac catheterization laboratory by non-anesthetists is also an issue, which can be sorted out by making policies and protocol in consultation with cardiologists.
PMCID: PMC4246841  PMID: 25436204
anesthesia; catheterization laboratory; cardiac
19.  Acute radiation dermatitis in breast cancer: topical therapy with vitamin E acetate in lipophilic gel base 
ecancermedicalscience  2010;4:190.
Radiotherapy can cause adverse skin reactions over the course of their treatment. Currently, management is based on several tropical products although there is no gold-standard approach to prevention and management of radiation toxicity.
We report our experience of vitamin E acetate in the treatment of radiation dermatitis in breast cancer patients who experienced grade 4 side effects (according to Radiation Therapy Oncology Group criteria).
Clinical management consisted of oral antibiotics and local application of vitamin E acetate and local escarectomy. All of the patients achieved complete re-epithelialization within 40 days.
Skin ulceration and necrosis post-radiation may interrupt oncological treatment in breast cancer patients. In acute radiodermatitis with skin necrosis, we propose the use of oral antibiotics together with escarectomy and the application of vitamin E acetate to facilitate the healing process in order to minimize the interruption to the oncological treatment.
PMCID: PMC3234031  PMID: 22276039
Radiation dermatitis; breast cancer; vitamin E
20.  Verification of the performance accuracy of a real-time skin-dose tracking system for interventional fluoroscopic procedures 
A tracking system has been developed to provide real-time feedback of skin dose and dose rate during interventional fluoroscopic procedures. The dose tracking system (DTS) calculates the radiation dose rate to the patient’s skin using the exposure technique parameters and exposure geometry obtained from the x-ray imaging system digital network (Toshiba Infinix) and presents the cumulative results in a color mapping on a 3D graphic of the patient. We performed a number of tests to verify the accuracy of the dose representation of this system. These tests included comparison of system–calculated dose-rate values with ionization-chamber (6 cc PTW) measured values with change in kVp, beam filter, field size, source-to-skin distance and beam angulation. To simulate a cardiac catheterization procedure, the ionization chamber was also placed at various positions on an Alderson Rando torso phantom and the dose agreement compared for a range of projection angles with the heart at isocenter. To assess the accuracy of the dose distribution representation, Gafchromic film (XR-RV3, ISP) was exposed with the beam at different locations. The DTS and film distributions were compared and excellent visual agreement was obtained within the cm-sized surface elements used for the patient graphic. The dose (rate) values agreed within about 10% for the range of variables tested. Correction factors could be applied to obtain even closer agreement since the variable values are known in real-time. The DTS provides skin-dose values and dose mapping with sufficient accuracy for use in monitoring diagnostic and interventional x-ray procedures.
PMCID: PMC3127243  PMID: 21731400
skin dose; dosimetry; radiation safety; cardiac fluoroscopic procedures; fluoroscopic dose; dose tracking; real-time dosimetry; fluoroscopic interventional procedures
21.  Persistent CT nephrograms following cardiac catheterisation and intervention: initial observations 
Insights into Imaging  2011;3(1):49-60.
To describe persistent nephrographic patterns detected by unenhanced renal CT at 24 h after cardiac catheterisation and intervention.
This prospective study was Health Insurance Portability and Accountability Act-compliant and institutional review board approved. Twenty-nine patients (20 men, nine women; average age 63.27 and range 41–85 years) agreed to undergo unenhanced dual-energy computed tomography (CT) limited to their kidneys at 24 h after cardiac catheterisation. CT attenuation values (Hounsfield units) were made from the cortical and medullary regions and single kidney total parenchymal iodine values (milligrams) were measured. Spearman’s rank correlation coefficient and a two-sided Fisher’s exact test were used in the statistics.
Focal nephrograms were observed in at least one kidney (range, one to five regions per kidney) in 10/29 (34%) of patients and bilateral global nephrograms in 13/29 (45%) of patients. Focal nephrograms correlated with cardiac catheterisation fluoroscopic time (r = 0.48; P = 0.0087). For global nephrograms, the total iodine content of right and left kidneys correlated with fluoroscopic time (r = 0.79 and 0.76; P < 0.0001, respectively) and the amount of contrast material (CM) used (r = 0.77 and r = 0.74; P < 0.0001, respectively).
Persistent focal and global nephrograms occur commonly as assessed by non-contrast CT at 24 h post cardiac catheterisation and our observations suggest they could be related to procedural factors.
Electronic supplementary material
The online version of this article (doi:10.1007/s13244-011-0131-2) contains supplementary material, which is available to authorized users.
PMCID: PMC3292644  PMID: 22695998
Cardiac; Interventional; Urogenital; Contrast media; CT
22.  Persistent CT nephrograms following cardiac catheterisation and intervention: initial observations 
Insights into Imaging  2011;3(1):49-60.
To describe persistent nephrographic patterns detected by unenhanced renal CT at 24 h after cardiac catheterisation and intervention.
This prospective study was Health Insurance Portability and Accountability Act-compliant and institutional review board approved. Twenty-nine patients (20 men, nine women; average age 63.27 and range 41–85 years) agreed to undergo unenhanced dual-energy computed tomography (CT) limited to their kidneys at 24 h after cardiac catheterisation. CT attenuation values (Hounsfield units) were made from the cortical and medullary regions and single kidney total parenchymal iodine values (milligrams) were measured. Spearman’s rank correlation coefficient and a two-sided Fisher’s exact test were used in the statistics.
Focal nephrograms were observed in at least one kidney (range, one to five regions per kidney) in 10/29 (34%) of patients and bilateral global nephrograms in 13/29 (45%) of patients. Focal nephrograms correlated with cardiac catheterisation fluoroscopic time (r = 0.48; P = 0.0087). For global nephrograms, the total iodine content of right and left kidneys correlated with fluoroscopic time (r = 0.79 and 0.76; P < 0.0001, respectively) and the amount of contrast material (CM) used (r = 0.77 and r = 0.74; P < 0.0001, respectively).
Persistent focal and global nephrograms occur commonly as assessed by non-contrast CT at 24 h post cardiac catheterisation and our observations suggest they could be related to procedural factors.
Electronic supplementary material
The online version of this article (doi:10.1007/s13244-011-0131-2) contains supplementary material, which is available to authorized users.
PMCID: PMC3292644  PMID: 22695998
Cardiac; Interventional; Urogenital; Contrast media; CT
23.  Historical Review of Cancer Risks in Medical Radiation Workers 
Radiation research  2010;174(6):793-808.
Epidemiologic studies of medical radiation workers have found excess risks of leukemia, skin and female breast cancer in those employed before 1950, but little consistent evidence of cancer risk increases subsequently. Occupational radiation-related dose-response, risk estimates for recent years, and lifetime cancer risk data are limited for radiologists and radiologic technologists and lacking for physicians and technologists performing or assisting with fluoroscopically-guided procedures. Based on data from 80 mostly small studies of cardiologists and substantially fewer studies of physicians in other specialties, estimated effective doses to physicians per interventional procedure vary by more than an order of magnitude. There is an urgent need to expand the limited base of information on average annual occupational radiation exposures and time-trends in doses received by medical radiation workers, to assess lifetime cancer risks of radiologists and radiologic technologists in the existing cohorts, and to initiate long-term follow-up studies of cancer and other radiation-associated disease risks in physicians and technologists performing or assisting with interventional procedures. Such studies will help to optimize standardized protocols for radiologic procedures, determine if current radiation protection measures are adequate, provide guidance on cancer screening needs, and yield valuable insights on cancer risks associated with chronic radiation exposure.
PMCID: PMC4098897  PMID: 21128805
radiologists; interventional radiologists; radiologic technologists; interventional cardiologists; neoplasms; reviews
24.  Automatic Monitoring of Localized Skin Dose with Fluoroscopic and Interventional Procedures 
Journal of Digital Imaging  2010;24(4):626-639.
This software tool locates and computes the intensity of radiation skin dose resulting from fluoroscopically guided interventional procedures. It is comprised of multiple modules. Using standardized body specific geometric values, a software module defines a set of male and female patients arbitarily positioned on a fluoroscopy table. Simulated X-ray angiographic (XA) equipment includes XRII and digital detectors with or without bi-plane configurations and left and right facing tables. Skin dose estimates are localized by computing the exposure to each 0.01 × 0.01 m2 on the surface of a patient irradiated by the X-ray beam. Digital Imaging and Communications in Medicine (DICOM) Structured Report Dose data sent to a modular dosimetry database automatically extracts the 11 XA tags necessary for peak skin dose computation. Skin dose calculation software uses these tags (gantry angles, air kerma at the patient entrance reference point, etc.) and applies appropriate corrections of exposure and beam location based on each irradiation event (fluoroscopy and acquistions). A physicist screen records the initial validation of the accuracy, patient and equipment geometry, DICOM compliance, exposure output calibration, backscatter factor, and table and pad attenuation once per system. A technologist screen specifies patient positioning, patient height and weight, and physician user. Peak skin dose is computed and localized; additionally, fluoroscopy duration and kerma area product values are electronically recorded and sent to the XA database. This approach fully addresses current limitations in meeting accreditation criteria, eliminates the need for paper logs at a XA console, and provides a method where automated ALARA montoring is possible including email and pager alerts.
PMCID: PMC3138926  PMID: 20706859
Peak skin dose; sentinal event; DICOM structured report dose; patient entrance reference point; fluoroscopy; interventional radiology; Joint Commission (JC); radiation dose; Digital Imaging and Communications in Medicine (DICOM)
25.  64-Slice Computed Tomographic Angiography for the Diagnosis of Intermediate Risk Coronary Artery Disease 
Executive Summary
In July 2009, the Medical Advisory Secretariat (MAS) began work on Non-Invasive Cardiac Imaging Technologies for the Diagnosis of Coronary Artery Disease (CAD), an evidence-based review of the literature surrounding different cardiac imaging modalities to ensure that appropriate technologies are accessed by patients suspected of having CAD. This project came about when the Health Services Branch at the Ministry of Health and Long-Term Care asked MAS to provide an evidentiary platform on effectiveness and cost-effectiveness of non-invasive cardiac imaging modalities.
After an initial review of the strategy and consultation with experts, MAS identified five key non-invasive cardiac imaging technologies for the diagnosis of CAD. Evidence-based analyses have been prepared for each of these five imaging modalities: cardiac magnetic resonance imaging, single photon emission computed tomography, 64-slice computed tomographic angiography, stress echocardiography, and stress echocardiography with contrast. For each technology, an economic analysis was also completed (where appropriate). A summary decision analytic model was then developed to encapsulate the data from each of these reports (available on the OHTAC and MAS website).
The Non-Invasive Cardiac Imaging Technologies for the Diagnosis of Coronary Artery Disease series is made up of the following reports, which can be publicly accessed at the MAS website at: or at
Single Photon Emission Computed Tomography for the Diagnosis of Coronary Artery Disease: An Evidence-Based Analysis
Stress Echocardiography for the Diagnosis of Coronary Artery Disease: An Evidence-Based Analysis
Stress Echocardiography with Contrast for the Diagnosis of Coronary Artery Disease: An Evidence-Based Analysis
64-Slice Computed Tomographic Angiography for the Diagnosis of Coronary Artery Disease: An Evidence-Based Analysis
Cardiac Magnetic Resonance Imaging for the Diagnosis of Coronary Artery Disease: An Evidence-Based Analysis
Pease note that two related evidence-based analyses of non-invasive cardiac imaging technologies for the assessment of myocardial viability are also available on the MAS website:
Positron Emission Tomography for the Assessment of Myocardial Viability: An Evidence-Based Analysis
Magnetic Resonance Imaging for the Assessment of Myocardial Viability: an Evidence-Based Analysis
The Toronto Health Economics and Technology Assessment Collaborative has also produced an associated economic report entitled:
The Relative Cost-effectiveness of Five Non-invasive Cardiac Imaging Technologies for Diagnosing Coronary Artery Disease in Ontario [Internet]. Available from:
The objective of this report is to determine the accuracy of computed tomographic angiography (CTA) compared to the more invasive option of coronary angiography (CA) in the detection of coronary artery disease (CAD) in stable (non-emergent) symptomatic patients.
CT Angiography
CTA is a cardiac imaging test that assesses the presence or absence, as well as the extent, of coronary artery stenosis for the diagnosis of CAD. As such, it is a test of cardiac structure and anatomy, in contrast to the other cardiac imaging modalities that assess cardiac function. It is, however, unclear as to whether cardiac structural features alone, in the absence cardiac function information, are sufficient to determine the presence or absence of intermediate pretest risk of CAD.
CTA technology is changing rapidly with increasing scan speeds and anticipated reductions in radiation exposure. Initial scanners based on 4, 8, 16, 32, and 64 slice machines have been available since the end of 2004. Although 320-slice machines are now available, these are not widely diffused and the existing published evidence is specific to 64-slice scanners. In general, CTA allows for 3-dimensional (3D) viewing of the coronary arteries derived from software algorithms of 2-dimensional (2D) images.
The advantage of CTA over CA, the gold standard for the diagnosis of CAD, is that it is relatively less invasive and may serve as a test in determining which patients are best suited for a CA. CA requires insertion of a catheter through an artery in the arm or leg up to the area being studied, yet both tests involve contrast agents and radiation exposure. Therefore, the identification of patients for whom CTA or CA is more appropriate may help to avoid more invasive tests, treatment delays, and unnecessary radiation exposure. The main advantage of CA, however, is that treatment can be administered in the same session as the test procedure and as such, it’s recommended for patients with a pre-test probability of CAD of ≥80%. The progression to the more invasive CA allows for the diagnosis and treatment in one session without the added radiation exposure from a previous CTA.
The visibility of arteries in CTA images is best in populations with a disease prevalence, or pre-test probabilities of CAD, of 40% to 80%, beyond which patients are considered at high pre-test probability. Visibility decreases with increasing prevalence as arteries become increasingly calcified (coronary artery calcification is based on the Agaston score). Such higher risk patients are not candidates for the less invasive diagnostic procedures and should proceed directly to CA, where treatment can be administered in conjunction with the test itself, while bypassing the radiation exposure from CTA.
CTA requires the addition of an ionated contrast, which can be administered only in patients with sufficient renal function (creatinine levels >30 micromoles/litre) to allow for the clearing of the contrast from the body. In some cases, the contrast is administered in patients with creatinine levels less than 30 micromoles/litre.
A second important criterion for the administration of the CTA is patient heart rate, which should be less than 65 beats/min for the single source CTA machines and less than 80 beats/min for the dual source machines. To decrease heart rates to these levels, beta-blockers are often required. Although the accuracy of these two machines does not differ, the dual source machines can be utilized in a higher proportion of patients than the single source machines for patients with heart beats of up to 80 beats/min. Approximately 10% of patients are considered ineligible for CTA because of this inability to decrease heart rates to the required levels. Additional contra-indications include renal insufficiency as described above and atrial fibrillation, with approximately 10% of intermediate risk patients ineligible for CTA due these contraindications. The duration of the procedure may be between 1 and 1.5 hours, with about 15 minutes for the CTA and the remaining time for the preparation of the patient.
CTA is licensed by Health Canada as a Class III device. Currently, two companies have licenses for 64-slice CT scanners, Toshiba Medical Systems Corporation (License 67604) and Philips Medical Systems (License 67599 and 73260).
Research Questions
How does the accuracy of CTA compare to the more invasive CA in the diagnosis of CAD in symptomatic patients at intermediate risk of the disease?
How does the accuracy for CTA compare to other modalities in the detection of CAD?
Research Methods
Literature Search
A literature search was performed on July 20, 2009 using OVID MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, EMBASE, the Cumulative Index to Nursing & Allied Health Literature (CINAHL), the Cochrane Library, and the International Agency for Health Technology Assessment (INAHTA) for studies published from January 1, 2004 until July 20, 2009. Abstracts were reviewed by a single reviewer and, for those studies meeting the eligibility criteria, full-text articles were obtained. Reference lists were also examined for any relevant studies not identified through the search. The quality of evidence was assessed as high, moderate, low or very low according to GRADE methodology.
Inclusion Criteria
English language articles and English or French-language HTAs published from January 1, 2004 to July 20, 2009.
Randomized controlled trials (RCTs), non-randomized clinical trials, systematic reviews and meta-analyses.
Studies of symptomatic patients at intermediate pre-test probability of CAD.
Studies of single source CTA compared to CA for the diagnosis of CAD.
Studies in which sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) could be established. HTAs, SRs, clinical trials, observational studies.
Exclusion Criteria
Non-English studies.
Pediatric populations.
Studies of patients at low or high pre-test probability of CAD.
Studies of unstable patients, e.g., emergency room visits, or a prior diagnosis of CAD.
Studies in patients with non-ischemic heart disease.
Studies in which outcomes were not specific to those of interest in this report.
Studies in which CTA was not compared to CA in a stable population.
Outcomes of Interest)
CAD defined as ≥50% stenosis.
Coronary angiography.
Measures of Interest
Sensitivity, specificity;
Negative predictive value (NPV), positive predictive value (PPV);
Area under the curve (AUC) and diagnostic odds ratios (DOR).
Results of Literature Search and Evidence-Based Analysis
The literature search yielded two HTAs, the first published by MAS in April 2005, the other from the Belgian Health Care Knowledge Centre published in 2008, as well as three recent non-randomized clinical studies. The three most significant studies concerning the accuracy of CTA versus CA are the CORE-64 study, the ACCURACY trial, and a prospective, multicenter, multivendor study conducted in the Netherlands. Five additional non-randomized studies were extracted from the Belgian Health Technology Assessment (2008).
To provide summary estimates of sensitivity, specificity, area under the SROC curve (AUC) and diagnostic odds rations (DORs), a meta-analysis of the above-mentioned studies was conducted. Pooled estimates of sensitivity and specificity were 97.7% (95%CI: 95.5% - 99.9%) and 78.8% (95%CI: 70.8% - 86.8%), respectively. These results indicate that the sensitivity of CTA is almost as good as CA, while its specificity is poorer. The diagnostic odds ratio (DOR) was estimated at 157.0 (95%CI: 11.2 - 302.7) and the AUC was found to be 0.94; however, the inability to provide confidence estimates for this estimate decreased its utility as an adequate outcome measure in this review.
This meta-analysis was limited by the significant heterogeneity between studies for both the pooled sensitivity and specificity (heterogeneity Chi-square p=0.000). To minimize these statistical concerns, the analysis was restricted to studies of intermediate risk patients with no previous history of cardiac events. Nevertheless, the underlying prevalence of CAD ranged from 24.8% to 78% between studies, indicating that there was still some variability in the pre-test probabilities of disease within this stable population. The variation in the prevalence of CAD, accompanied with differences in the proportion of calcification, likely affected the specificity directly and the sensitivity indirectly across studies.
In February 2010, the results of the Ontario Multi-detector Computed Tomography Coronary Angiography Study (OMCAS) became available and were thus included in a second meta-analysis of the above studies. The OMCAS was a non-randomized double-blind study conducted in 3 centers in Ontario that was conducted as a result of a MAS review from 2005 requesting an evaluation of the accuracy of 64-slice CTA for CAD detection. Within 10 days of their scheduled CA, all patients received an additional evaluation with CTA. Included in the meta-analysis with the above-mentioned studies are 117 symptomatic patients with intermediate probability of CAD (10% - 90% probability), resulting in a pooled sensitivity of 96.1% (95%CI: 94.0%-98.3%) and pooled specificity of 81.5% (95%CI: 73.0% - 89.9%).
Summary of Findings
CTA is almost as good as CA in detecting true positives but poorer in the rate of false positives. The main value of CTA may be in ruling out significant CAD.
Increased prevalence of CAD decreases study specificity, whereas specificity is increased in the presence of increased arterial calcification even in lower prevalence studies.
Positive CT angiograms may require additional tests such as stress tests or the more invasive CA, partly to identify false positives.
Radiation exposure is an important safety concern that needs to be considered, particularly the cumulative exposures from repeat CTAs.
PMCID: PMC3377576  PMID: 23074388

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