Combined Therapy of Radiofrequency Ablation and Ethanol Injection of Rabbit Liver: An <Emphasis Type="Italic">In Vivo</Emphasis> Feasibility Study

Our purpose was to compare the effects of percutaneous radiofrequency ablation (RFA) combined with percutaneous ethanol injection (PEI) on the extent of ablation in in vivo rabbit liver tissue as compared with either therapy alone. Twenty-two New Zealand white rabbits were included in this study and allocated into three groups: group A: conventional RFA (n = 6); group B: PEI (n = 6); group C: combined RFA and PEI (n = 10). For combined RFA and PEI, under ultrasound guidance, 1 mL of absolute ethanol was injected into the target area of the liver parenchyma through a 21-gauge Chiba needle before performing RFA. RFA was performed using a 17- gauge internally cooled electrode with 1-cm active tip, and RF energy (30 W) was applied for 3 minutes, with or without ethanol injection. After RFA or PEI, contrast-enhanced computed tomography and CT-pathologic correlation were performed. The short- axis and long-axis diameters of thermal lesions of each group were compared. All procedures were technically successful and a total of 38 lesions were produced. The mean short-axis and long-axis diameter of the coagulation necrosis in rabbits of group C (combination of RFA and PEI), were significantly larger than those of other groups: group A: 10.3 ± 2 mm and 11.4 ± 2 mm; group B: 3.1 ± 1 mm and 4.3 ± 2 mm; group C: 12.8 ± 3 mm and 17.8 ± 6 mm (p < 0.05). On contrast-enhanced CT scan, the lesions of rabbits of the group C appeared to be more frequently irregular compared to those of group A (20% in group A vs. 67% in group C). There were three complications including two localized hematomas and one cardiopulmonary failure. Combined RFA and PEI could increase the dimension of coagulation necrosis without increasing complications and therefore, may be successfully used for treating larger lesions.     

Gastrointestinal stromal tumors of the duodenum: CT and barium study findings

OBJECTIVE: The purpose of this study was to describe the CT and radiographic features of gastrointestinal stromal tumors of the duodenum. CONCLUSION: Gastrointestinal stromal tumors of the duodenum appear on barium studies as extrinsically compressing or submucosal masses with or without ulceration. These tumors usually appear on contrast-enhanced CT as well-defined masses with an exoenteric growth pattern and relatively good heterogeneous enhancement.     

Using MRI to evaluate anatomic significance of aortic bifurcation, right renal artery, and conus medullaris when locating lumbar vertebral segments

OBJECTIVE: This study evaluated the anatomic significance and sites of aortic bifurcation, right renal artery, and conus medullaris when locating lumbar vertebral segments on MRI. SUBJECTS AND METHODS. The study group was composed of 210 patients who underwent MRI of the lumbosacral spine. The position of aortic bifurcation was evaluated using MRI. Midline and sagittal MRI were also assessed to identify the proximal portion of the right renal artery and the tip of the conus medullaris. These locations were recorded in relation to the upper or lower half of the adjacent vertebral body or the adjacent intervertebral disk space. RESULTS: The most common site of aortic bifurcation was at the L4 vertebra (83%). In most patients two separated iliac arteries were apparent at the level of the L4-L5 disk space (93%), and the right renal artery was located between the lower half of the L1 vertebra and the upper half of the L2 vertebra (92%). The position of the conus medullaris was variably located, and the most frequent site was at the L1 vertebra (56%). CONCLUSION: The aortic bifurcation, the right renal artery, and the combination of these structures can be reliable landmarks for determining the lumbar vertebral segments on MRI or CT. However, conus medullaris cannot be considered a good landmark because of its variable locations.     

Increased nephron volume is not a cause of supranormal renographic differential renal function in patients with ureteropelvic junction obstruction

PURPOSE: Increasing clinical importance is being placed on the role of differential renal function (DRF) in the management of congenital ureteropelvic junction obstruction. Supranormal DRF of the hydronephrotic kidney on renal scan is a puzzling phenomenon and is hypothesized to be due to an increase in single nephron filtration or nephron volume without sound evidence. We studied the histopathological changes of hydronephrotic kidneys to determine whether glomerular hypertrophy underlies supranormal DRF. MATERIALS AND METHODS: We retrospectively evaluated the records of 3 females and 32 males with unilateral congenital hydronephrosis who underwent pyeloplasty. Mean patient age at operation was 12.6 months (range 0.1 to 144). Needle biopsies from 3 different sites at the lower pole of the kidney were performed during surgery. To evaluate the presence of glomerular hypertrophy, the maximal planar area of glomeruli was measured under light microscopy using an image analyzer. Tissue samples obtained from kidneys without a history of urinary tract disease at autopsy were used as controls. The mean glomerular areas of the patient and control groups were evaluated according to DRF and age. RESULTS: The mean glomerular area values of the patient group were smaller than those of the control group, except for 4 patients. The glomerular areas of the hydronephrotic kidneys with supranormal DRF were not significantly different from those of the control group. Instead, the probability of larger renal glomeruli increased with decreasing DRF (p = 0.1155). CONCLUSIONS: Increased nephron volume can be discounted as a cause of supranormal DRF.     

Voiding diary for the evaluation of urinary incontinence and lower urinary tract symptoms: prospective assessment of patient compliance and burden

AIMS: Voiding diary duration may be related to patient compliance and burden. To test this hypothesis, we evaluated patient compliance and burden. METHODS: Between January and July 2002, we prospectively evaluated 162 patients (57 males and 105 females, mean age 53.0, range 20-81 years) with stress urinary incontinence or lower urinary tract symptoms. At the initial visit, all patients underwent a detailed clinical evaluation including an International Prostate Symptom Score (I-PSS) assessment and were randomly requested to complete 2-day, 3-day, or 7-day voiding diaries (the three study groups). At the second visit, a simple self-administered questionnaire was completed by all patients. The questionnaire included 11 items on subject demographics and voiding diary-keeping. RESULTS: No significant differences were found in either the accuracy of diary-keeping or the daily average number of omissions when the three groups were compared. However, as the diary duration increased, the mean burden scores increased (P = 0.005), and the mean preferred duration of the diary in the 7-day group was significantly higher than that of the 2-day or 3-day groups (P < 0.001). After categorizing patients into two groups according to the degree of patient burden, members of the group with a greater perceived burden were found to have a significantly higher I-PSS quality of life score (P = 0.045) and to have kept a diary for a longer time (P = 0.038). CONCLUSIONS: Our results suggest that keeping a diary for 7 days may increase patient burden and thus, we recommend that the 7-day diary should be reduced to cover fewer days.