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Thomas C Winter

Publications and source records attributed to Thomas C Winter.

5 recordsLinked to original sources
PubMed2003

Postbiopsy bleeding in a porcine model: reduction with radio-frequency ablation--preliminary results.

PURPOSE: To test a biopsy needle modified for use of radio-frequency (RF) energy to produce hemostasis after core biopsy of liver or kidney. MATERIALS AND METHODS: RF energy was applied to a partially insulated 17-gauge needle, and tip temperature was monitored with a thermocouple. Domestic Yorkshire pigs (n = 4; mean weight, 23.4 kg) were anesthetized, and their livers and kidneys were exposed. Needles were inserted 2 cm into hepatic and renal parenchyma and retracted, either with or without tract ablation to 65 degrees C, in normal tissue, animals treated with anticoagulants, and an animal with acute inferior vena caval occlusion to produce portal hypertension. Blood loss was assessed by weighing surgical sponges with blood from the puncture sites. Significant differences in blood loss between control and ablated biopsy specimens in each scenario were tested by using a Wilcoxon matched-pairs signed rank test. RESULTS: Mean blood loss for each group was as follows: In the liver, control biopsy specimens (n = 18) lost 0.30 g while ablated biopsy specimens lost 0.00044 g (P <.01), and control biopsy specimens treated with heparin (n = 26) lost 0.45 g while biopsy specimens treated with heparin and ablation lost 0.27 g (P =.03). For inferior vena caval occlusion, control biopsy specimens lost 1.23 g, while ablated biopsy specimens lost 0.00 g. In the kidney, control biopsy specimens (n = 28) lost 0.82 g, while ablated biopsy specimens lost 0.24 g (P =.01), and control biopsy specimens treated with heparin (n = 14) lost 1.04 g, while biopsy specimens treated with heparin and ablation lost 0.19 g (P =.02). CONCLUSION: Tract ablation with thermocouple-monitored RF energy decreased postprocedural hemorrhage after hepatic and renal biopsy.

Animals↗
PubMed2003

Using a saline chaser to decrease contrast media in abdominal CT.

OBJECTIVE: The purpose of this study was to compare hepatic tumor conspicuity on CT after injection of either 150 mL of contrast material or 100 mL of contrast material plus a 50-mL saline chaser. SUBJECTS AND METHODS: We evaluated 86 hypoattenuating liver metastases in 26 patients. Patients underwent CT in two sessions separated by a mean of 85 days: one time with 150 mL of contrast material and the other time with 100 mL of contrast material followed by a 50-mL saline chaser. The order of the sessions was randomized. Contrast material was administered via power injector and matched for injection rate and delay time. Attenuation values were obtained from normal liver tissue and metastases and from the spleen, kidney, aorta, and inferior vena cava. RESULTS: The 150 mL dose of contrast material caused slightly greater liver and tumor attenuation than 100 mL of contrast material with a chaser (mean hepatic attenuation, 95.6 vs 89.8 H, respectively; p < 0.03, paired t test; mean tumor attenuation, 53.2 vs 49.1 H, respectively; r = 0.71, p = 0.09). The difference in conspicuity of liver lesions was slightly greater with 150 mL than with 100 mL with a chaser (46.8 H vs 44.2 H; r = 0.46, p = 0.08, paired t test), but was of doubtful clinical significance (2.6 H). Kidney, spleen, and vascular structures enhanced more with 150 mL than with 100 mL and a chaser. CONCLUSION: Using 100 mL of contrast material and a saline chaser did not result in a meaningful difference in liver parenchyma attenuation or lesion conspicuity compared with using 150 mL of contrast medium alone. Routine use of a chaser for abdominal CT may yield cost savings and a decreased risk of contrast nephropathy.

Adult↗
PubMed2002

Dynamic sonography with valgus stress to assess elbow ulnar collateral ligament injury in baseball pitchers.

Sonography is a valuable method for imaging superficial tendons and ligaments. The ability to obtain comparison images easily with dynamic stress allows assessment of ligament and tendon integrity. We studied the medial elbow joints of two baseball pitchers using MR imaging and dynamic sonography. Both sonography and MR imaging identified the ulnar collateral ligament tears. Dynamic sonography uniquely demonstrated the medial joint instability.

Adolescent↗