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1.  Renal Ablation Update 
Thermal ablative technologies have evolved considerably in the recent past and are now an important component of current clinical guidelines for the treatment of small renal masses. Both radiofrequency ablation and cryoablation have intermediate-term oncologic control that rivals surgical options, with favorable complication profiles. Studies comparing cryoablation and radiofrequency ablation show no significant difference in oncologic control or complication profile between the two modalities. Early data from small series with microwave ablation have shown similar promising results. Newer technologies including irreversible electroporation and high-intensity–focused ultrasound have theoretical advantages, but will require further research before becoming a routine part of the ablation armamentarium. The purpose of this review article is to discuss the current ablative technologies available, briefly review their mechanisms of action, discuss technical aspects of each, and provide current data supporting their use.
PMCID: PMC4078154  PMID: 25049445
small renal mass; cryoablation; radiofrequency; microwave; irreversible electroporation; interventional radiology
2.  Interrelation of preventive care benefits and shared costs under the Affordable Care Act (ACA) 
With the implementation of the Affordable Care Act (ACA), access to insurance and coverage of preventive care services has been expanded. By removing the barrier of shared costs for preventive care, it is expected that an increase in utilization of preventive care services will reduce the cost of chronic diseases. Early detection and treatment is anticipated to be less costly than treatment at full onset of chronic conditions. One concern of early detection of disease is the cost to treat. In reality, the confluence of early detection may result in greater overall expenditures. Even with improved access to preventive care benefits, cost-sharing of other health services remains a major component of insurance plans. In order to treat identified conditions or diseases, cost-sharing comes into play. With the greater adoption of cost-sharing insurance plans, expenditures on the part of enrollee are anticipated to rise. Once the healthcare recipients realize the implication of early identification and resultant treatment costs, enrollment in preventive care may decline. Healthcare legislation and regulation should consider the full spectrum of care and the microeconomic costs associated with preventive treatment. Although the system at large may not realize the immediate impact, behavioral shifts on the part of healthcare consumers may alter healthcare. Rather than the current status quo of treating presenting conditions, preventive treatment is largely anticipated to require more resources and may impact the consumer’s financial capacity. This report will explore how these two concepts are co-dependent, and highlight the need for continued reform.
PMCID: PMC4154552  PMID: 25197679
Preventive Care; Affordable Care Act (ACA); Shared Costs; Cost Management; Insurance Accessibility
3.  Human Health Risk Assessment of 16 Priority Polycyclic Aromatic Hydrocarbons in Soils of Chattanooga, Tennessee, USA 
Water, air, and soil pollution  2012;223(9):5535-5548.
South Chattanooga has been home to foundries, coke furnaces, chemical, wood preserving, tanning and textile plants for over 100 years. Most of the industries were in place before any significant development of residential property in the area. During the 1950s and 1960s, however, the government purchased inexpensive property and constructed public housing projects in South Chattanooga. Many neighborhoods that surround the Chattanooga Creek were previous dumping grounds for industry. Polycyclic aromatic hydrocarbons (PAHs) comprised the largest component of the dumping and airborne industrial emissions. To address the human exposure to these PAHs, a broad study of South Chattanooga soil contaminant concentrations was conducted on 20 sites across the city. Sixteen priority pollutant PAHs were quantified at two depths (0-10cm and 10-20cm) and compared against reference site soils, as well as to soils from industrially-impacted areas in Germany, China, and the US. From these data, the probability that people would encounter levels exceeding EPA Residential Preliminary Remediation Goals (PRG) was calculated. Results indicate that South Chattanooga soils have relatively high concentrations of total PAHs, specifically Benzo[a]pyrene (B[a]P). These high concentrations of B[a]P were somewhat ubiquitous in South Chattanooga. Indeed, there is a high probability (88%) of encountering soil in South Chattanooga that exceeds the EPA PRG for B[a]P. However, there is a low probability (15%) of encountering a site with ∑PAHs exceeding EPA PRG guidelines.
PMCID: PMC3521527  PMID: 23243323
Benzo(a)pyrene; Polycyclic aromatic hydrocarbons; PAHs; Residential preliminary remedial goal; South Chattanooga
4.  Central Venous Line Placement prior to Gastric Bypass Improves Operating Room Efficiency 
ISRN Surgery  2012;2012:816871.
Background. Bariatric surgery has increased across America. Venous access is difficult in these patients. Anesthesiologists often utilize valuable operating room (OR) time acquiring reliable intravenous lines. Our objective was to determine if outpatient central venous line (CVL) placement improves OR efficiency and professional reimbursement for CVL insertion. Methods. In our bariatric practice, selected surgery patients have outpatient CVLs placed during prophylactic vena cava filter placement. In a cohort of 268 gastric bypass patients operated between 1/01 and 11/06, we compared time-to-incision between 106 with pre-established CVLs and 162 without. In addition, we determined professional compensation rates for CVLs placed outpatient versus CVLs inserted in the OR. Results. Patients with preoperative (outpatient) CVLs required 35.6 ± 12.5 minutes to skin incision compared with 42.5 ± 13.9 minutes for controls (P < 0.0001), and 34.9% had skin incision in <30 minutes compared with 16.4% of controls. Radiologists collected 28.2% of outpatient billings for CPT code 36556, compared with anesthesiologists who collected <1% when placing CVLs in the OR. Conclusions. Outpatient CVLs prior to gastric bypass improve efficiency in the OR with earlier skin incision. Professional reimbursement is better for outpatient CVLs than intraoperative inpatient CVLs.
PMCID: PMC3399345  PMID: 22830049
5.  Use Of Yttrium-90 Microspheres In Patients With Advanced Hepatocellular Carcinoma & Portal Vein Thrombosis 
Patients with portal vein thrombosis (PVT) and hepatocellular carcinoma (HCC) have limited treatment options due to increased disease burden and diminished hepatic perfusion. 90Y-microspheres may be better tolerated than chemoembolization in these patients. Here we review the safety and efficacy of 90Y-microsphere use for HCC with major PVT.
Materials and Methods
A retrospective review of HCC with main (n=10) or first (n=12) branch PVT treated with 90Y-microspheres (n=22) was conducted. CLIP scores ranged from 2 to 5 with 18% scoring 4 or greater. Response was determined 8-12 weeks following treatment using magnetic resonance or computed tomography and RECIST criteria. Overall survival was estimated by the Kaplan-Meier method.
32 treatments (26 glass, 6 resin) were administered to 22 patients. Common grade 1–2 toxicities included abdominal pain (38%), nausea (28%), fatigue (22%). Four post-therapy hospitalizations occurred, all <48hrs in duration. 1 death occurred 10 days following therapy Response data: 2 partial responses, progressive disease 42%, stable disease 50% of treatments. Median overall survival (OS) was 7 months from time of initial 90Y-microsphere treatment. Child-Pugh A patients had a median OS of 7.7 months; B and C = 2.7 months (p = 0.01). Median OS for CLIP scores 2–3 was 7 months versus 1.3 months for scores 4–5 (p = 0.04).
90Y-microspheres are tolerated in patients with HCC and major PVT. Compared with chemoembolization, rates of severe adverse events appear low. Radiographic response rates are low. Median OS of 7 months is promising and warrants further study versus systemic therapy.
PMCID: PMC2945527  PMID: 20691606
6.  Vessel Target Location Estimation During the TIPS Procedure 
Medical image analysis  2009;13(3):519-529.
Creation of a Transjugular Intrahepatic Portosystemic Shunt (TIPS) requires passage of a needle toward a moving target that is only seen transiently by x-ray prior to needle passage. Intraoperative, 3D target localization would facilitate target access and improve the safety of the procedure. The clinical assumption is that patients undergoing the TIPS procedure possess rigid, cirrhotic livers that undergo only intraoperative translation without significant deformation or rotation. Based upon this assumption, we hypothesize that the position of any unseen, 3D target point within the liver can be determined intraoperatively by precalculation of the relative positions of the target point to a different 3D point that can be tracked intraoperatively. This paper examines this hypothesis using intraoperatively acquired, biplane, x-ray images of 7 patients. In 6, we tracked the effects of cardiac and respiratory motion, and in 3 the effects of needle pressure. Methods involved reconstruction of 3D vessel bifurcation and other trackable intrahepatic points from biplane angiograms, measurement of liver deformation by examining changing distances between these 3D points over time, and comparison of expected to actual displacements of these points with respect to a fixed reference point in the liver. We conclude that, for the rigid livers associated with patients undergoing TIPS, that there is less intraoperative deformation than previously reported by other groups addressing healthy liver deformation, and that the location of an unseen target can be predicted within 3 mm accuracy.
PMCID: PMC2715565  PMID: 19332378
Liver deformation; 2D/3D point reconstruction; TIPS; X-Rays
7.  Demonstration of Dose and Scatter Reductions for Interior Computed Tomography 
With continuing developments in computed tomography (CT) technology and its increasing use of CT imaging, the ionizing radiation dose from CT is becoming a major public concern particularly for high-dose applications such as cardiac imaging. We recently proposed a novel interior tomography approach for x-ray dose reduction that is very different from all the previously proposed methods. Our method only uses the projection data for the rays passing through the desired region of interest. This method not only reduces x-ray dose but scatter as well. In this paper, we quantify the reduction in the amount of x-ray dose and scattered radiation that could be achieved using this method. Results indicate that interior tomography may reduce the x-ray dose by 18% to 58% and scatter to the detectors by 19% to 59% as the FOV is reduced from 50 to 8.6 cm.
PMCID: PMC2860287  PMID: 19940669
computed tomography (CT); cardiac CT; interior tomography; Farmer chamber; pencil chamber; x-ray dose reduction; x-ray scatter reduction; CTDI
Injection of oil of turpentine into the peritoneal cavity of a dog calls forth immediately an exudate of fluid from the surrounding tissues. The amount of fluid reaches the maximum on the third day and has practically disappeared on the fifth day. The cell content of this fluid is very small at first, but increases rapidly. The type of the predominating cells also changes. In the early exudate the small mononuclear cells are numerous and the large mononuclears few. Later the number of large mononuclear cells is increased and ultimately the polymorphonuclear cells preponderate. Various forms of atypical cells also occur. Much of the fluid and many of the cells are removed by way of the thoracic duct. The counts of the cells in the thoracic duct and the estimates based on these indicate that the duct does not remove all of the fluid or cells from the peritoneal cavity. Much fluid is probably taken back directly into the blood, as are many of the cells. Some of the cells make their way to the lymph nodes, while many perhaps undergo complete autolysis in the serous cavity. The polymorphonuclear cells do not enter the thoracic duct in great numbers. Examination of the lymph from the thoracic duct in the case of my dogs showed the types of cells that are usually found there. The variation in small mononuclear cells is so related to the cell content of the peritoneal effusion as to indicate that the supply in the blood is maintained from this source. The form and staining qualities of the cells indicate that many of the small mononuclear cells are returned to the thoracic duct. The ratio of polymorphonuclear cells present in the lymph bears no definite relation to the other features of the process. The transitional cells were increased in number and in their ratio to other cells. The increase in the transitional types accompanies an increase in large mononuclear cells and a decrease in small mononuclears. None of the atypical forms of cells found in the effusion were seen in the lymph. The number of eosinophils is without apparent relation to the other features of the process. No polymorphonuclear cells containing the pigment injected were found in the lymph of the thoracic duct, and the number of mononuclear cells containing pigment was small. Much pigment was deposited in the lymph nodes. Detailed and definite conclusions as to the relation between the cells of the lymph and those of the effusion cannot be arrived at satisfactorily without repeated observations on the same animal. Dr. Warthin examined many of the smears from these cases and frequently controlled the conclusions regarding the various types of cells. Dr. P. F. Morse assisted me frequently with the operative procedures and with the routine counting of the cells.
PMCID: PMC2125242  PMID: 19867559
1. Splenectomy in dogs results in an immediate increase of cells in the thoracic duct lymph, due to the manipulation involved in the operation. This increase is soon followed by a low cell count, attributable to the removal of an important source of the cells under consideration. Several months after the operation, a normal cell count is reëstablished, due probably to a readjustment of activity on the part of other cell-forming tissues. 2. Pilocarpin injections after splenectomy result in an increase of cells, attributable to an increased activity of the respiratory organs and of the intestine. 3. After the injection of pilocarpin, splenectomy may increase the cell count, but it causes a decrease sooner than in cases of pilocarpin injection not followed by splenectomy.
PMCID: PMC2124937  PMID: 19867506

Results 1-12 (12)