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991.

Background and purpose

To determine landmarks for stent positioning in both ureteral orifices (UOs) and the gender differences in their location in men and women.

Patients and methods

The location of the UO and the bladder neck (BN) was measured fluoroscopically by the intravesical distal location of an open-ended catheter marked with radiopaque materials. We compared the location in men (n = 12) and women (n = 12) with a full bladder (hydrostatic pressure of 50 cmH2O) or an empty bladder.

Results

The mean distances from BN to UO in men and women were significantly different both in an empty bladder (2.5 ± 0.4 and 2.1 ± 0.3 cm, respectively) and in a full bladder (2.9 ± 1.0 and 2.3 ± 0.6 cm, respectively). The location of UO was changed by bladder filling in women but not in men. In women, most UOs were found superior to the symphysis pubis (SP) in empty bladder (66.6 %). Most of this location was observed at behind the upper boarder of SP in full bladder of women (75 %). The BN of women was located at the lower level in basal state compared to men. Also, the location of BN was markedly changed by bladder fulling in women (p = 0.04) but not in men.

Conclusions

Significant gender differences were observed in the location of UO and BN. Clinicians should keep in mind the anatomical differences between men and women during fluoroscopic-guided procedure.  相似文献   
992.

Background

The purpose of the present study was to evaluate the clinicopathologic factors and ultrasound (US) features predictive of central lymph node metastasis (LNM) in patients diagnosed with papillary thyroid microcarcinoma (PTMC).

Methods

From March 2008 to August 2008, the clinicopathologic features and preoperative US features of 483 patients who were diagnosed with conventional PTMC were included. Medical records, US features, and pathology reports of all patients were retrospectively reviewed. Univariate and multivariate analysis was performed to identify clinicopathological prognostic factors associated with central LNM. Odds ratios (OR) with relative 95 % confidence intervals (95 % CI) were calculated to determine the relevance of all potential predictors of central LNM.

Results

Among the 483 patients with PTMC, 139 (28.8 %) patients had central LNM. The OR of significant independent factors were 2.055 (95 % CI, 1.137–3.716), 2.075 (95 % CI, 1.27–3.39), 1.71 (95 % CI, 1.073–2.724), and 15.897 (95 % CI, 4.173–60.569), respectively, for bilaterality, larger tumor size (>5 mm), extracapsular invasion, and lateral LNM. No significant association was seen among the US features of PTMC with central LNM.

Conclusions

Central lymph node metastasis in patients with PTMC was significantly associated with various clinicopathological factors, including larger tumor size (>5 mm), bilaterality, extracapsular invasion, and lateral LNM. When these features are detected on preoperative US, selective central compartment dissection may be helpful in patients diagnosed with PTMC.  相似文献   
993.

Background

Incidental findings of gallbladder cancer (GBCA) have dramatically increased as an initial presentation of the disease because of the expansion of laparoscopic cholecystectomy. However, the optimal management of T2 GBCA remains at issue.

Methods

We compared our 10-year experience with the consensus surgical strategy for T2 GBCA. Between January 2000 and December 2009, 70 patients at Severance Hospital, Yonsei University Health System, Seoul, Korea, underwent surgical treatment for GBCA stage T2. The medical records of 70 patients with T2 GBCA were retrospectively reviewed.

Results

Radical cholecystectomy was performed on only 32 (45.8 %) patients. In patients with T2 GBCA and positive lymph nodes (LN), the overall survival rate between cholecystectomy with LN dissection and radical cholecystectomy did not show a significant difference. Twenty patients experienced recurrence during the follow-up period. Among the 11 patients who underwent cholecystectomy with liver resection, only 2 (18.2 %) patients had an intrahepatic recurrence. Of the 9 patients who underwent cholecystectomy without liver resection, 3 (33.3 %) patients had an intrahepatic recurrence. However, recurrences at the gallbladder bed occurred only in one and two patients, respectively, and were not significantly different between the two groups.

Conclusions

There was a large gap between clinical practice and treatment guidelines. Though relatively few patients enrolled in this study experienced recurrence, cholecystectomy and LN dissection without liver resection showed similar survival and recurrence patterns compared with those of radical cholecystectomy. To improve consistency between clinical practice and consensus guidelines, the role of limited resection for T2 lesions needs further evaluation.  相似文献   
994.

Background

The present study was performed to elucidate the influence of postoperative complications on the prognosis and recurrence patterns of periampullary cancer after pancreaticoduodenectomy (PD).

Methods

Clinical data were reviewed from 200 consecutive patients who had periampullary cancer and underwent PD between October 2003 and July 2010, and survival outcomes and recurrence patterns were analyzed. Postoperative complications were classified according to a modification of Clavien’s classification.

Results

Overall, 86 major complications of grade II or higher occurred in 71 patients. The patients were classified into two groups according to the presence of postoperative complications of grade II or higher: group Cx?, absence of complications (n = 129); and group Cx+, presence of complications (n = 71). There were no differences in gender, mean age, tumor node metastasis stage, biliary drainage, type of resection, and radicality between the two groups (P > 0.05). The 3-year overall and disease-free survival rates of the group Cx+ patients (31.0 and 22.3 %, respectively) were significantly lower than those of the group Cx? patients (49.0 and 40.0 %; P = 0.003 and 0.002, respectively). The multivariate analysis showed that postoperative complications (P = 0.001; RR = 1.887; 95 % confidence interval [CI] 1.278–2.785), a T stage of T3 or T4 (P = 0.001; RR = 2.503; 95 % CI 1.441–4.346), positive node metastasis (P = 0.001; RR = 2.093; 95 % CI, 1.378–3.179), R1 or R2 resection (P = 0.023; RR = 1.863; 95 % CI 1.090–3.187), and angiolymphatic invasion (P = 0.013; RR = 1.676; 95 % CI 1.117–2.513) were independent prognostic factors for disease-free survival. Regarding recurrence patterns, group Cx+ patients exhibited more distant recurrences than did group Cx? patients (P = 0.025).

Conclusions

Postoperative complications affect prognosis and recurrence patterns in patients with periampullary cancer after PD.  相似文献   
995.
996.

Purpose

This prospective, randomized trial was designed to assess whether the i-gel supraglottic airway device is suitable for volume-controlled ventilation while applying positive end-expiratory pressure (PEEP) of 5 cmH2O under general anesthesia. It was believed that this device might improve arterial oxygenation.

Methods

Forty adult patients (aged 20–60 years) scheduled for elective orthopedic surgery were enrolled in this study. Twenty patients were ventilated without external PEEP [zero positive end-expiratory pressure (ZEEP) group], and the other 20 were ventilated with PEEP 5 cmH2O (PEEP group) after placing an i-gel device. Volume-controlled ventilation at a tidal volume (TV) of 8 ml/kg of ideal body weight, leak volume, and arterial blood gas analysis were investigated.

Results

The incidences of a significant leak were similar in the ZEEP and PEEP groups (3/20 and 1/20, respectively; P = 0.605), as were leak volumes. No significant PaO2 difference was observed between the two groups at 1 h after satisfactory i-gel insertion (215 ± 38 vs. 222 ± 54; P = 0.502).

Conclusions

The use of an i-gel during PEEP application at 5 cmH2O did not increase the incidence of a significant air leak, and a PEEP of 5 cmH2O failed to improve arterial oxygenation during controlled ventilation in healthy adult patients.  相似文献   
997.

Background and aims

The best therapeutic modality has not been established for gastric low-grade adenomas or dysplasia (LGD), which can progress to invasive carcinoma despite a low risk. This study aims to investigate the clinical efficacy, safety, and local recurrence after argon plasma coagulation (APC) treatment of gastric LGD compared with endoscopic submucosal dissection (ESD).

Patients and methods

A total of 320 patients with gastric LGD ≤2.0 cm treated with APC or ESD between 2004 and 2011 were retrospectively analyzed. We compared local recurrence rate, complication rate, procedure time, and admission to hospital between APC and ESD groups.

Results

Of the 320 patients, 116 patients were treated with APC and 204 with ESD. During follow-up, local recurrence was more common in the APC group (3.8 %, 4/106) than the ESD group (0.5 %, 1/188; log-rank test P = 0.036). However, all patients with local recurrence (n = 5) were treated by additional APC, and followed up without further recurrences. ESD was complicated by two perforations (1.0 %, 2/204) compared with no perforations in the APC group (0 %, 0/116). Bleeding complications were not different between the APC (1.7 %, 2/116) and ESD (2.0 %, 4/204) groups. Procedure time was shorter in the APC (7.8 ± 5.1 min) than the ESD (53.1 ± 38.1 min) group (P < 0.001). The proportion of hospitalization was less in the APC group (31.0 %, 36/116) than the ESD group (100.0 %, 204/204) (P < 0.001).

Conclusions

APC can be a good treatment option for patients with LGD ≤2.0 cm.  相似文献   
998.

Background

Spleen-preserving distal pancreatectomy can be performed safely and effectively by resecting both splenic vessels (Warshaw procedure) [14]. This simplified spleen-preserving technique might also be applied to minimally invasive distal pancreatectomy of benign and borderline malignant tumor [5, 6].

Methods

Although the conservation of both splenic vessels is paramount to preserving the spleen during laparoscopic distal pancreatectomy, preservation of the splenic vessels is not always possible, especially under the following conditions: (1) relatively large tumor, (2) associated with chronic pancreatitis, (3) tumor abutting splenic vascular structures, and (4) bleeding during the splenic vessel conserving procedure, which are potential indications of laparoscopic extended Warshaw procedure. Patient preparation and position was the same as that described in our previous study [7].

Results

During the study’s time period, 38 consecutive patients underwent laparoscopic spleen-preserving distal pancreatectomy. Of those, five patients underwent a laparoscopic extended Warshaw procedure, which all included among 16 patients of extended distal pancreatectomy by dividing the pancreas at the pancreatic neck. All patients were women with a median age of 55 (range, 38–75) years. Median total operation time and blood loss were 215 (range, 200–386) minutes and 100 (range, 0–300) ml, respectively. The median length of hospital stay was 8 (range, 5–15) days. All of postoperative complications (two grade A and two grade B postoperative pancreatic fistula; one grade A bleeding) were able to be treated conservatively. During the median follow-up period of 11 (range, 7–42) months, one focal splenic infarction and one gastric varix were noted; however, no clinically significant complications were reported.

Conclusions

Laparoscopic spleen-preserving extended distal pancreatectomy with resection of both the splenic vessels is feasible and safe [8]. This surgical technique is thought to increase the chance of preservation of the spleen with minimally invasive distal pancreatectomy in well-selected benign or borderline malignant tumor of the distal pancreas.  相似文献   
999.

Background

Since delta-shaped gastroduodenostomy was introduced, many surgeons have utilized laparoscopic distal gastrectomy (LDG) with totally intracorporeal Billroth I (ICBI) for gastric cancer, because it is expected to have several advantages over laparoscopic-assisted distal gastrectomy with extracorporeal Billroth I (ECBI). In this study, we compared these two reconstruction options to evaluate their outcomes.

Methods

The data of 166 gastric cancer patients who underwent LDG performed by a single surgeon between April 2009 and February 2012 were analyzed retrospectively. The subjects were divided into ECBI (n = 106) and ICBI (n = 60) groups, and then the clinical characteristics, surgical outcomes, symptoms, and change in BMI at 3 months after surgery were compared. Furthermore, a rapid systematic review and meta-analysis were conducted.

Results

The operative time was significantly shorter in the ICBI group (197.4 ± 45.5 vs. 157.1 ± 43.9 min), but blood loss was similar between the groups. Regarding surgical outcomes, there were no significant differences in the length of hospital stay, soft diet initiation, visual analogue scale, frequency of analgesics injection, and postoperative white blood cell counts and C-reactive protein levels between the groups. The surgical complication rates were 5.7 and 13.3 % in the ECBI and ICBI groups, respectively, and one case of anastomosis leakage was observed in each group. At 3 months after surgery, reflux symptoms were more frequent in the ICBI group, but other gastrointestinal symptoms and the change of BMI were similar between the groups. The meta-analysis revealed no significant differences in the operative time, time to first flatus, length of hospital stay, frequency of analgesic usages, and rates of anastomosis complications between the groups.

Conclusions

We could not demonstrate the clinical superiority of ICBI over ECBI based on our data and a rapid systematic review and meta-analysis. The anastomosis method may be selected according to patient conditions and the surgeon’s preference.  相似文献   
1000.

Background

Endoscopic submucosal dissection (ESD) is a well-established method for the treatment of gastrointestinal epithelial tumors. However, the treatment of gastric subepithelial tumors (SETs) that originate from the muscularis propria layer still depends primarily on surgical techniques. We evaluated the appropriate indications for ESD in the treatment of SETs that originate from the muscularis propria layer.

Methods

Thirty-five patients with gastric SETs that originate from the muscularis propria layer who underwent ESD were enrolled, and the charts were retrospectively reviewed to investigate the parameters predictive complete resection and complications.

Results

The mean age of the patients was 54.15 ± 9.3 years, and the male/female ratio was 2:3. Twenty-eight of the 35 SETs (85.7 %) were movable, and 15 (45.7 %) had a positive rolling sign. The most frequent location of the SETs was high body (n = 14). The most common pathological diagnoses were leiomyoma (60 %) and gastrointestinal stromal tumor (28.6 %). The complete resection rate was 74.3 %. A positive rolling sign (p = 0.022) and small tumor size (≤20 mm; p = 0.038) were significantly associated with complete resection. Two patients (6.1 %) developed perforations that required surgical treatment; their SMTs were neurogenic tumors with fixed lesion. Tumor mobility was significantly associated with perforation (p = 0.017).

Conclusions

The ESD method appears to be relatively safe for use in the complete resection of SETs that originate from the muscularis propria layer. Small tumor size (≤20 mm) and a positive rolling sign are appropriate indications for ESD.  相似文献   
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