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41.

Purpose

To evaluate the influence of percutaneous cryoablation for renal cell carcinoma on function of the affected kidney.

Materials and Methods

Between June 2016 and September 2017 at our institution, 12 inoperable patients underwent 15 cryoablation sessions for 17 small renal tumors. Of these, 9 patients who underwent 11 sessions of cryoablation were the focus of this study. For those patients, time-dependent changes in postoperative renal function were investigated by a retrospective review of clinical records. Evaluated were the estimated glomerular filtration rate (eGFR) and scintigraphy using 99m technetium-mercaptoacetyltriglycine (99mTc-MAG3) before and 1 week, 1–2 months, and more than 6 months after cryoablation.

Results

Mean baseline eGFR was 76.88 ± 29.82 mL/min/1.73 m2 (mean ± standard deviation; range, 23.4–112.5). Mean eGFR 1 week, 1–2 months, and more than 6 months after cryoablation were 74.56 ± 26.68 mL/min/1.73 m2 (21.0–101.1), 69.5 ± 25.28 mL/min/1.73 m2 (24.1–105.6), and 75.08 ± 26.25 mL/min/1.73 m2 (29.0–107.3), respectively. Changes were statistically insignificant (P = .6044, P = .6699, and P = .9038, respectively). Regarding split renal function, the mean baseline contribution of the affected kidney determined by 99mTc-MAG3 was 47.27% ± 6.14 (38.8%–57.0%). Mean contributions of the affected kidney 1 week after, 1–2 months after, and more than 6 months after cryoablation were 44.40% ± 5.37 (38.3%–53.6%), 44.57% ± 6.52 (34.35%–55.0%), and 45.41% ± 7.77 (34.4%–56.5%), respectively. Differences from baseline were significant for the earliest 2 periods (P = .0473 and P = .0334, respectively) but not the later period (P = .2532).

Conclusions

Results suggested that total renal function does not worsen after cryoablation; however, function of the affected kidney worsened after cryoablation but later partially recovered.  相似文献   
42.
Purpose To evaluate the efficacy and safety of Gunther tulip retrievable vena cava filter (GTF) implantation to prevent pulmonary embolism during intravenously administered thrombolytic and anticoagulation therapy and interventional radiological therapy for occlusive or nonocclusive deep venous thrombosis (DVT) of the lower extremity.Methods We evaluated placement of 55 GTFs in 42 patients with lower extremity DVT who had undergone various treatments including those utilizing techniques of interventional radiology.Results Worsening of pulmonary embolism in patients with existing pulmonary embolism or in those without pulmonary embolism at the time of GTF insertion was avoided in all patients. All attempts at implantation of the GTF were safely accomplished. Perforation and migration experienced by one patient was the only complication. Mean period of treatment for DVT under protection from pulmonary embolism by the GTF was 12.7 ± 8.3 days (mean ± SD, range 4–37 days). We attempted retrieval of GTFs in 18 patients in whom the venous thrombus had disappeared after therapy, and retrieval in one of these 18 cases failed. GTFs were left in the vena cava in 24 patients for permanent use when the DVT was refractory to treatment.Conclusion The ability of the GTF to protect against pulmonary embolism during treatment of DVT was demonstrated. Safety in both placement and retrieval was clarified. Because replacement with a permanent filter was not required, use of the GTF was convenient when further protection from complicated pulmonary embolism was necessary.  相似文献   
43.
Purpose To evaluate the feasibility and safety of withdrawal of a Gunther tulip retrievable vena cava filter (GTF). Methods Between June 2001 and December 2005, at our institution 86 GTFs were implanted for temporary caval filtration in 59 patients (37 women, 22 men; mean age 59.3 years, range 18–87 years). For GTFs retrieved thereafter, we retrospectively reviewed the following parameters: rate of success in retrieval, degree of trapped thrombus in the filter, and complications during retrieval. Results Worsening of or new development of pulmonary embolism after filter implantation did not occur in any patient. Of the 86 GTFs implanted, retrieval of 80 was attempted. Among those 80 filters, 77 (96%) were successfully retrieved (with the standard method, n = 72; with the modified method, n = 5) without any complication. The period of implantation of the retrieved filters was 13.4 ± 4.2 days. In the 5 filters that were filled to a height of ≥ 1/4 with trapped thrombus, retrieval was performed after attempts were made to decrease trapped thrombi. In addition, a temporary filter or another GTF was temporarily placed at the cephalad level of the GTF during this removal procedure. Conclusion GTFs can be retrieved in the majority of cases. Even when encountering situations in which the filter could not be removed using the standard method, withdrawal was possible in a high frequency of cases through various trials using modified methods.  相似文献   
44.
Purpose: To evaluate the efficacy of hepatic port-catheter system placement without distal catheter tip occlusion or gastroduodenal artery embolization distal to the catheter tip.

Material and Methods: A port-catheter system was percutaneously implanted in 29 patients (16 men, 13 women; mean age 65.6 years) with unresectable liver cancer. Persistent blood flow through the end hole of the catheter was verified immediately and 1-10 days after catheter placement.

Results: In all cases, percutaneous port-catheter placement was successfully performed. In seven of 29 (24.1%) patients, flow through the end hole of the catheter was verified immediately after the procedure. However, no flow was seen 1-10 days after the procedure.

Conclusion: It is not necessary to occlude the end hole of the catheter tip and embolize the gastroduodenal artery beyond the catheter tip when placing a port-catheter system for repeated hepatic arterial infusion chemotherapy.  相似文献   
45.
OBJECTIVE: The purpose of our study was to compare persistent hepatofugal blood flow in the gastroduodenal artery after implanting a port-catheter system for repeated hepatic arterial infusion chemotherapy using either the original or the modified fixed catheter tip method. With the original method the lumen of the catheter tip is closed with a microcoil; with the modified method it is left open. Persistent hepatofugal blood flow can induce reactive gastric or duodenal mucosal lesions. MATERIALS AND METHODS: A port-catheter system with the catheter tip fixed to the gastroduodenal artery by embolic agents was percutaneously implanted in 156 patients (102 men, 54 women; mean age, 63.2 years) with unresectable liver cancer. In 98 patients the original method was used, and in 58 patients the modified method was used. Existence of persistent blood flow beyond the indwelling catheter tip as shown on arteriography via the port performed immediately and 2-10 days after port-catheter placement was compared between these two groups. RESULTS: In all cases, percutaneous port-catheter placement was successfully performed. In one (1.0%) of 98 procedures involving the original method, the gastroduodenal artery was detected on arteriography just after implantation, compared with 23 (39.7%) of 58 procedures using the modified method. However, arteriography performed 2-10 days (mean, 5.02 days) after implantation detected the gastroduodenal artery in only one case. CONCLUSION: This retrospective study indicates that closure of the end hole appears to occur spontaneously shortly after implantation. Thus, such closure is not always necessary to avoid persistent hepatofugal blood flow in the gastroduodenal artery.  相似文献   
46.
PURPOSE: For therapeutic effectiveness of repeated hepatic arterial infusion chemotherapy (HAIC) for unresectable advanced liver malignancies, distribution of anticancer drugs via an indwelling catheter should be uniform throughout the entire liver. It was investigated how an extrahepatic artery entering the posterior segment or caudate lobe of the liver influences performance of repeated HAIC. MATERIALS AND METHODS: One hundred ninety-five patients with unresectable advanced liver cancer underwent placement of a percutaneously implantable port-catheter system and were followed arteriographically with and without computed tomography (CT). The frequency of poor distribution in the posterior segment or caudate lobe of the liver was observed on CT during arteriography via the port for HAIC. The correlation between poor distribution and various factors including the number of intrahepatic arteries was studied, and the management of such poor distribution is described. RESULTS: In 34 of 195 patients (17.4%), poor distribution was observed in the posterior segment and/or caudate lobe of the liver. The rate of poor distribution was significantly higher in those with two or more hepatic arteries than in those with one (13 of 35 vs 21 of 160; P = .0007, chi2 test). Other evaluated factors were not significantly correlated with such poor distribution. The right inferior phrenic artery was successfully embolized in 22 patients with tumors in segments with poor distribution. Good distribution throughout the entire liver was achieved in 21 patients (95.5%). CONCLUSION: Inflow of the right inferior phrenic artery into the liver occasionally prevents distribution of anticancer drugs throughout the entire liver during performance of long-term HAIC.  相似文献   
47.
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49.
PURPOSE: To evaluate the effects of anti-alphabeta T cell receptor monoclonal antibody (R73) on the induction of experimental autoimmune uveoretinitis (EAU) in rats. METHODS: Lewis rats in which EAU was induced were treated with R73. All rats were examined for the clinical course of EAU, pathological findings of the globe, delayed-type hypersensitivity, and the interleukin-2 (IL-2) gene and protein expression in the eye. RESULTS: The R73 treatment was effective for delaying EAU onset, decreasing the severity of EAU, and suppressing delayed-type hypersensitivity to the antigen. IL-2 gene and protein expression was reduced by R73 treatment in the anterior and posterior segments of the eye. CONCLUSION: R73 treatment is effective for suppression of the development of EAU, inhibiting IL-2 expression in the eye.  相似文献   
50.
This study examined the validity of nursery teachers' report on the physical activity of young children. Subjects were twenty-one children aged 3 to 4 years (12 boys and 9 girls) at a nursery in Toyama Prefecture, Japan. Children were equipped with the Actiwatch (Mini-mitter Company Inc.) activity monitor and the Caloriecounter Select II (Kenz, Co, Ltd) for three consecutive weekdays to assess their daily physical activity levels. Nursery teachers completed a questionnaire containing questions on children's activity level during the measurement periods at the nursery. The results showed that subjects with a high frequency of physical activity were significantly associated with an increasing trend in total energy expenditure and activity counts per day. Children whose physical activity was rated as "very often" had a significantly higher activity level per day from the Actiwatch instrument, compared with peers whose physical activity was rated as "not often" (570.5 +/- 192.8 counts vs. 334.9 +/- 123.4 counts, p < 0.05). Regarding energy expenditure originating from physical activity and steps per day from the Caloriecounter, a significant difference was found between "very active" children and "inactive" children as rated by the nursery teachers (140.7 +/- 17.5 kcal vs. 78.2 +/- 17.4 kcal, p < 0.05; 16103 +/- 1896 steps vs. 10038 +/- 32 steps, p < 0.05). This study indicates that children's physical activity level as reported by their teachers in nursery surroundings is in accordance with the objective data from the Actiwatch and the Caloriecounter. The results suggest that nursery teachers' respondent for children in physical activity may be used as a valid measure to evaluate young children's physical activity levels, especially in nursery setting.  相似文献   
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