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71.
PURPOSE: To assess whether coaxial placement of uncovered and covered expandable nitinol stents overcomes the disadvantages of the increased migration rate seen with covered stents and the tumor ingrowth seen in uncovered stents in the treatment of malignant gastric outlet obstructions. MATERIALS AND METHODS: Two types of expandable nitinol stent were designed: an uncovered stent and a covered stent. Under fluoroscopic guidance, the uncovered and covered stents were placed coaxially with complete overlap in 39 consecutive patients with malignant gastric outlet obstruction caused by stomach cancer. Food intake capacity was graded on a scale of 0-4. Stent patency rate was estimated by the Kaplan-Meier method. RESULTS: Technical success rate was 97% (38 of 39 patients). After stent placement, food intake capacity improved at least one grade in 36 patients. Stent migration occurred in three patients (8%), that is, partial (n = 2) or complete (n = 1) upward migration of the inner covered stent into the stomach. Two of these patients were treated by placement of an additional covered stent. During the mean follow-up period of 134 days (range, 15-569 d), 10 patients developed recurrent symptoms of obstruction with tumor overgrowth being the most common cause. Nine underwent placement of an additional covered stent with good results. The median period of primary stent patency was 157 days (mean, 278 d). The 30-, 60-, and 180-day patency rates were 97%, 91%, and 39%, respectively. Four patients (10%) died within 1 month after the procedure. CONCLUSION: Coaxial stent placement technique seems to contribute to decreasing the migration rate of the stent and decrease the rate of recurrent obstruction by preventing or delaying tumor ingrowth.  相似文献   
72.
73.

Introduction and hypothesis

The purpose of this study was to evaluate the intra- and postoperative urologic complications and management in patients with cervical or endometrial cancer treated with laparoscopic radical hysterectomy and lymphadenectomy.

Methods

We retrospectively reviewed the medical records of 146 patients with cervical or endometrial cancer who underwent total laparoscopic radical hysterectomy with lymphadenectomy between August 2002 and April 2011. The intra- and postoperative urologic complications were analyzed.

Results

Double ureteral stents were inserted prophylactically in 13 patients (8.9?%), 2 of whom had postoperative urologic complications. Nine patients (6.2?%) had postoperative urologic complications. Of four patients with ureterovaginal fistulas, two were treated conservatively with cystoscopic placement of ureteral stents and two underwent ureteroneocystostomies. Vesicovaginal fistulas occurred in two patients, both of whom underwent vesicovaginal fistula repairs. One patient noted to have a bladder injury intraoperatively had a laparoscopic repair, and one patient noted to have a ureteral injury postoperatively was treated conservatively with cystoscopic placement of ureteral stents.

Conclusions

Iatrogenic lower urinary tract injuries during laparoscopic radical hysterectomy are relatively common complications. Intraoperative prophylactic ureteral stent insertion and the early detection of urologic complications postoperatively is advised for patients who undergo laparoscopic radical hysterectomies.  相似文献   
74.
OBJECTIVES: The purpose of this study is to evaluate the correlation of the perfusion parameters of 3-dimensional, contrast-enhanced magnetic resonance (MR) imaging (3D CEMRI) with pulmonary function test (PFT) and quantitative computed tomography (CT) parameters in patients with chronic obstructive pulmonary disease (COPD). MATERIALS AND METHODS: In 14 patients with COPD, 3D CEMRI was performed. From the signal intensity-time curves, pulmonary blood flow (PBF), pulmonary blood volume (PBV), and mean transit time of each pixel was calculated. From the volumetric CT data, the quantitative parameters including the volume fraction of the lung below -950 Housefield Units (V(-950)) and mean lung density were assessed. The correlation between the MR perfusion parameters and the parameters from quantitative CT and PFT was assessed using Spearman correlation analysis. The correspondence of the regional impairment of perfusion on MR perfusion maps to the areas of emphysema on quantitative CT maps in each patient was assessed qualitatively using a 4-class visual scoring method by 2 readers. RESULTS: All 3D CEMRI examinations were successfully completed and MR perfusion parameters were obtained in all patients. The Spearman correlation test showed that PBF positively correlated with forced expiratory volume in 1 second (FEV(1))/forced vital capacity (FVC) (R = 0.49, P = 0.044), PBV positively correlated with FEV(1)/FVC (R = 0.69, P = 0.006) and negatively correlated with V-950 (R = -0.61, P = 0.020), and mean transit time positively correlated with FEV(1) (R = 0.63, P = 0.017) and FEV(1)/FVC (R = 0.76, P = 0.002). The areas of perfusion impairment on PBF and PBV maps were relatively well correlated with the areas of emphysema on CT maps [very good or good: PBF 71.5% (reader 1) and 64.3% (reader 2) of the patients, kappa = 0.47 (P < 0.001); PBV 78.6% (reader 1) and 78.6% (reader 2) of the patients, kappa = 0.89 (P < 0.001)]. CONCLUSIONS: This study shows that the deterioration of perfusion parameters measured on MR in patients with COPD, correlates with worsening of airflow limitation on PFT and emphysema index on CT. Regional heterogeneity of emphysema on CT matches with the decreased perfusion on MR.  相似文献   
75.

Objective

Although partial nephrectomy (PN) is the standard treatment for localized clinical T1a renal cell carcinoma (RCC), treatment of larger renal tumors is controversial. We evaluated the oncological outcomes and perioperative complications after radical and PN for RCC ≥4 cm.

Patients and methods

We retrospectively analyzed the data of 2,373 patients surgically treated for nonmetastatic RCC with clinical T1b or T2 (≥4 cm). The propensity scores for surgery type were calculated, and the partial group was matched to the radical group in a 1:3 ratio. The oncological outcomes were compared using Kaplan-Meier analysis and multivariate Cox regression models were used to identify the independent predictors of progression-free, cancer-specific, and overall survival.

Results

All differences in preoperative clinical characteristics disappeared after matching. There were no significant differences in progression-free, cancer-specific, or overall survival between the partial and radical groups in the matched cohort. The patients’ age, tumor size, cellular grade, and pathologic stage were independent predictors for all 3 survival outcomes. However, early complications (<30 d postoperative) were significantly more common in the partial group (P<0.001). In a subgroup analysis of the patients with clinical T2 stage, there were no significant differences in all 3 survival outcomes.

Conclusions

The partial and radical nephrectomy groups had equivalent oncological outcomes. Although the early complication rate was significantly higher after PN, it should be considered as a valuable treatment option even in patients with clinical T1b or higher RCC.  相似文献   
76.

Purpose

This study was conducted to determine the effect of age at diagnosis and length of ganglionated bowel resected on postoperative Hirschsprung-associated enterocolitis (HAEC).

Methods

Children who underwent endorectal pull-through (ERPT) between January 1993 and December 2004 were retrospectively reviewed. t Test, analysis of variance, Kaplan-Meier, and Cox's proportional hazards analyses were performed.

Results

Fifty-two children with Hirschsprung disease (median age, 25 days; range, 2 days-16 years) were included. Nineteen (37%) had admissions for HAEC. Proportional hazards regression showed that HAEC admissions decreased by 30% with each doubling of age at diagnosis (P = .03) and increased 9-fold when postoperative stricture was present (P < .01), after controlling for type of ERPT, trisomy 21, transition zone level, and preoperative enterocolitis. Thirty-six children, with age at initial operation less than 6 months, were grouped based on length of ganglionated bowel excised (A [5 cm] and B [>5 cm]). No significant difference in the number of HAEC admissions during initial 2 years post-ERPT was seen between groups A (n = 18) and B (n = 18). The study had a power of 0.8 to detect a difference of 1 admission over 2 years.

Conclusions

Children diagnosed with Hirschsprung disease at younger ages are at a greater risk for postoperative enterocolitis. Excising a longer margin of ganglionated bowel (>5 cm) does not seem to be beneficial in decreasing HAEC admissions.  相似文献   
77.
Vascular smooth muscle cell (VSMC) proliferation and extracellular matrix (ECM) accumulation play key roles in the development and the progression of vascular remodeling such as transplant arteriosclerosis and restenosis. The present study examined the effects of sirolimus (SRL) on platelet-derived growth factor (PDGF)-induced fibronectin secretion, collagen synthesis, and the related signaling pathways including reactive oxygen species (ROS) and mitogen-activated protein kinases (MAPK) in rat VSMCs. Primary rat VSMCs were isolated from male Sprague-Dawley rats. Growth arrested, synchronized cells were treated with various concentrations of SRL before the addition of PDGF at 10 ng/mL. Proliferating cell nuclear antigen expression, fibronectin secretion, and the activation of extracellular signal-regulated protein kinase (ERK) and p38 MAPK were assessed by Western blot analysis, collagen synthesis by [(3)H]-proline incorporation, and cellular ROS by flow cytometry. PDGF (10 ng/mL) increased VSMC proliferation by 1.7-fold, fibronectin secretion by 1.5-fold, collagen synthesis by 2.1-fold, cellular ROS by 1.6-fold, and activation of ERK and p38 MAPK by 3.3- and 3.9-fold compared to controls. SRL above 1 nmol/L inhibited PDGF-induced VSMC proliferation and collagen synthesis but not PDGF-induced fibronectin secretion, cellular ROS, and activation of ERK and p38 MAPK. These data demonstrated that PDGF increased ECM synthesis as well as proliferation through cellular ROS and subsequent MAPK activation and that SRL inhibited PDGF-induced VSMC proliferation and collagen synthesis in a cellular ROS- and MAPK activation-independent way.  相似文献   
78.

Background

A web-based survey was conducted among colorectal surgeons who represented members of both SAGES and ASCRS to find out how they define conversion for laparoscopic colorectal surgery.

Methods

Questionnaires were designed based on MCQs, including three parts: surgeon information, different definitions for conversion, and four different clinical scenarios. Surgeons were asked to choose the best definition(s).

Results

325 (28.5%) of 1,140 surgeons, 28.5% responded; approximately half of them were part of private-based practices. Fifty-three percent had more than 10 years experience; 35.9% performed more than 50 laparoscopic colon cases per year, 12% performed more than 25 laparoscopic rectal cases per year, and 60% less than 10. The majority (68.4%) agreed that any incision made earlier than planned is conversion. Whereas 81.4% felt that incision >5 cm is not a conversion, only 53.4% considered incision >10 cm a conversion, and 37% did not. Neither extracorporeal vessel ligation (73.8%), bowel resection (81.2%), anastomosis (77%), or incision made for specimen retrieval (91.1%) was counted as conversion. In clinical case scenarios, 62% found an incision made to facilitate phlegmon dissection after laparoscopically mobilizing the left colon up to and around the splenic flexure to be laparoscopic-assisted. A 10-cm incision required for fistula take down after finishing laparoscopic dissection was defined as conversion (55.6%). A 10-cm incision made for the rectal dissection in rectopexy was described as conversion in 51% and laparoscopic-assisted in 48%. Increasing a 5–12-cm for specimen extraction, 49.3% was declared a laparoscopic-assisted case.

Conclusions

It was considered clear that any incision made earlier than planned a conversion, whereas extra corporeal vessel ligation, bowel resection and anastomosis were not. However, there seem to be many views of conversion regarding incision length, and some clinical situations that might influence outcome among different centers.  相似文献   
79.

OBJECTIVE

To evaluate the long‐term results and predictive risk factors for efficacy after the tension‐free vaginal tape (TVT) procedure for treating female stress urinary incontinence (SUI).

PATIENTS AND METHODS

Inall, 306 women (mean age 50.7 years, sd 8.7) who had a TVT procedure for SUI were selected and followed ≥7 years (mean 92.3 months, range 84–110) after surgery. We analysed the long‐term results, the variables predictive of cure rates, and patient satisfaction.

RESULTS

The overall 7‐year cure rate was 84.6%, with a satisfaction rate of 69.3%. The cure rates were lower in patients with high‐grade SUI (50% in grade III, 82.8% in grade II and 90.7% in grade I; P < 0.001). On multivariate analysis, there were no independent risk factors related to cure rate, and urgency was the only factor independently associated with patient satisfaction (P = 0.008; odds ratio 2.47). Seventy‐one patients (23.2%) had complications at the 1‐month follow‐up after surgery, but only eight (2.6%) had complications at the 7‐year follow‐up, including mesh exposure in six and de novo urgency in two.

CONCLUSION

The absence of long‐term adverse events associated with the TVT procedure, and high subjective and objective 7‐year success rates with no independent predictive factors affecting the long‐term cure rate, make the TVT procedure a recommendable surgical treatment for female SUI.  相似文献   
80.
A 74-year-old woman was diagnosed with hilar bile duct cancer, and underwent a curative resection of the bile duct and the left and caudate lobes of the liver in 1995. Ten years later (April 2005), she noted a small mass in the abdominal wall. The mass slowly enlarged to reach 4 cm in diameter by January 2007. With a diagnosis of a possible recurrence of bile duct cancer, a laparotomy was thus performed. The abdominal wall tumor was buried in the rectus abdominis muscle and was tightly attached to the ileum. The lesion was resected en bloc with the associated rectus muscle and ileocecal region. A histopathological examination of the resected specimen revealed tubular adenocarcinoma that closely resembled the original primary bile duct cancer. In addition, the immunohistochemical staining pattern of the abdominal tumor was identical to that of the original bile duct cancer. This indicated that the abdominal tumor represented a local recurrence (probably due to peritoneal implantation) at 12 years after the resection of the hilar bile duct cancer. This case emphasizes that long-time surveillance is required for patients with bile duct cancer, even if they have survived without recurrence for more than 5 years after a curative resection.  相似文献   
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