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91.
Background  Magnetic anchoring guidance systems (MAGS) are composed of an internal surgical instrument controlled by an external handheld magnet and do not require a dedicated surgical port. Therefore, this system may help to reduce internal and external collision of instruments associated with laparoendoscopic single-site (LESS) surgery. Herein, we describe the initial clinical experience with a magnetically anchored camera system used during laparoscopic nephrectomy and appendectomy in two human patients. Methods  Two separate cases were performed using a single-incision working port with the addition of a magnetically anchored camera that was controlled externally with a magnet. Results  Surgery was successful in both cases. Nephrectomy was completed in 120 min with 150 ml estimated blood loss (EBL) and the patient was discharged home on postoperative day 2. Appendectomy was successfully completed in 55 min with EBL of 10 ml and the patient was discharged home the following morning. Conclusions  Use of a MAGS camera results in fewer instrument collisions, improves surgical working space, and provides an image comparable to that in standard laparoscopy.  相似文献   
92.
Purpose  The laparoscopic approach to radical and partial nephrectomy is becoming the standard of care for treating patients with renal tumors. Hand-assisted laparoscopic partial nephrectomy (HALPN) provides some advantages over the pure laparoscopic approach which include manual manipulation of the kidney, tactile feedback, and timely specimen removal. Materials and methods  We describe our technique for HALPN and emphasize the implementation of an in-room pathologist to examine gross margins during the period of renal arterial occlusion. Between 2004 and 2007, 46 patients underwent HALPN performed by the same surgeons. Mean patient age was 59.5 years and mean tumor size was 2.55 cm. Twelve of these patients underwent significant concomitant procedures. Results  Our mean operating time was 173.26 min (range 90–306 min) and our mean warm ischemic time was 28.32 min (range 14–54 min). Average estimated blood loss was 116.82 ml (range 10–1000 ml) with no transfusions. Thirty-six (78%) tumors were renal cell carcinoma, seven (15%) were oncocytomas, and three (7%) were angiomyolipomas. The average length of stay was 5.17 days (range 3–9 days) and there were no positive margins. There was one postoperative bleed (2%) and two postoperative urine leaks (4.3%). Discussion  In our institution, the hand-assist approach to laparoscopic partial nephrectomy has resulted in favorable perioperative outcomes. The use of an in-room pathologist to provide real-time assessment of gross tumor margins has allowed us to achieve a 0% positive final margin rate. We believe that the use of an in-room pathologist during the timely extraction of the specimen made possible by the hand-assisted approach provides a great advantage over pure laparoscopic partial nephrectomy. This low positive margin rate is also the result of maintaining a bloodless field of resection with temporary renal arterial occlusion as well as the avoidance of visual tissue distortion with cold, sharp scissor dissection. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
93.
介绍了医用超声技术在眼科学、神经学、血管学、心脏病学、消化系统、泌尿科学、产科学和妇科学、外科(手术)学的主要应用,并论述了经颅二维及彩色多普勒技术、组织谐波成像技术、三维成像技术和扩展视野成像技术在临床上的价值.  相似文献   
94.
Aims –  The objective of this study was to analyse the upper urinary tract (UT) function in a group of consecutive multiple sclerosis (MS) patients, who had not previously been treated by urologist.
Materials and methods –  Ninety-two MS patients suffering from lower UT dysfunction were included in the study. The group of patients consisted of 69 women and 23 men. The average Expanded Disability Status Scale (EDSS) score in our group was 4.29 (0–8.5). Functional examination of the kidneys using assessment of creatinine clearance and morphological examination of the kidneys using ultrasound was performed in all patients. Analysis of the upper UT function is presented.
Results –  The average serum creatinine clearance in our group was 132.84 ml/min/1.73 m2 (46.8–510). Lower levels than normal were found in three patients (3.3%). Abnormal ultrasound findings were recorded in five patients (5.4%). The creatinine clearance was correlated with the clinical subtype of MS, the severity expressed by EDSS, the urodynamic parameters, the duration of the disease, the duration of the symptoms of lower UT and the EDSS score. We did not find a statistically significant correlation for any of these parameters.
Conclusions –  Our results suggest that impairment of the upper UT function is exceptional in MS patients.  相似文献   
95.
Color Doppler Imaging Predicts Portal Invasion by Pancreatic Adenocarcinoma   总被引:9,自引:0,他引:9  
Background Tumor infiltration of the intima of the portal vein (PV) and superior mesenteric vein (SMV) by pancreatic adenocarcinoma is classically considered a criterion for unsuitability for resection and poor prognosis. This study was performed to evaluate modern color duplex imaging (CDI) for the assessment of PV/SMV infiltration by pancreatic adenocarcinomas. Method From 1994 to 2005, Whipple’s procedure or pylorus-preserving pancreato-duodenectomy (PPPD) was performed in 303 patients with pancreatic adenocarcinoma; 35 of these underwent partial PV/SMV resection. Applying a previously reported CDI score, we evaluated the integrity of the echogenic border layer between the vein and tumor (mural demarcation) and maximum blood flow velocity (V max) in the PV segment in contact with the tumor. The results were compared to the final histological findings in the resected venous walls. Results CDI findings correlated well with the histological invasion grades. By measuring V max and evaluating mural demarcation, we observed a sensitivity of 66.7% and 100% and a specificity of 98.3% and 93.9%, respectively, in predicting full thickness vein invasion, including the intima. V max above 80 cm/s and lack of mural demarcation were predictors of PV/SMV invasion. The postoperative survival rates depended on the depth of tumor infiltration into the PV/SMV. Conclusions Modern CDI is a reliable and valid technique for evaluation of morphological and hemodynamic parameters in the portal vein segment adjacent to pancreatic adenocarcinoma. Maximal blood-flow velocity in the portal segment in contact with the tumor and absence of the echogenic vessel-parenchymal sonographic interface are parameters predictive of tumor infiltration of the portal intima.  相似文献   
96.
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98.
BACKGROUND: Few studies have addressed the effect of vasodilatory stimuli on the intrarenal arterial system in type 2 diabetes mellitus (DM), and factors affecting its responsiveness. METHODS: One hundred twenty-four patients with type 2 DM without renal failure were enrolled, and 25 subjects served as controls. Using duplex Doppler sonography, resistive indices (RI) of interlobar arteries were measured before and after sublingual nitroglycerine (NTG) (0.3 mg) spray over a 10-min period. RESULTS: Per cent changes in RI (%DeltaRI) in the DM group were significantly less than in controls (P<0.05), as was the area over the %DeltaRI-time curve (AOC-%DeltaRI, total responsiveness to nitroglycerine) (P<0.05). In the DM group, significant negative correlations were found between AOC-%DeltaRI and age (r=-0.492, P<0.0001). AOC-%DeltaRI in DM patients with proteinuria was significantly lower than without it (P<0.003). AOC-%DeltaRI in smokers was also significantly lower than in nonsmokers (P<0.05). By multiple regression analysis of the DM group, AOC-%DeltaRI was found to be significantly and independently affected by age (beta=-0.394), smoking (beta=-0.211), and the presence of proteinuria (beta=-0.270; R(2)=0.354, P<0.0001). CONCLUSIONS: Diabetic patients have a lower level of responsiveness to NTG. Advanced age, smoking, and proteinuria significantly affect response to NTG in DM patients, suggesting that advanced intrarenal arteriosclerosis may be contributory. Smoking is suggested to be a risk factor for progression of diabetic nephropathy, likely contributing to poor responsiveness of the intrarenal arterial system to vasodilatory stimuli.  相似文献   
99.
目的对照下肢顺行静脉造影,评价双功能多普勒彩超在CVI术后复发病例的诊断价值。方法针对22例24侧下肢慢性静脉功能不全(CVI)术后复发肢体,应用双功能多普勒彩超和下肢顺行静脉造影,明确复发原因并比较两者优缺点。结果从复发原因看,95.83%(23/24)的病例存在交通静脉功能不全,70.83%(17/24)的病例存在隐静脉主干及部分属支残留,66.67%(16/24)的病例存在深静脉瓣膜功能不全。在判断静脉通畅性上,下肢静脉造影优于双功彩超,其诊断准确率达100%,无一漏诊;两者在深静脉功能判断上符合率87.5%;双功能彩超在隐静脉主干及近侧属支阳性检出率达100%,高于下肢静脉造影,后者的符合率为79.16%;双功能彩超能精确定位交通静脉,对交通静脉的漏诊率(5.11%)低于下肢顺行静脉造影(28.31%)。结论双功能彩超对CVI术后复发病例的病因及定位诊断,尤其是隐-股静脉交界处的病因分析和交通静脉精确定位,具有下肢静脉造影不可替代的优势。  相似文献   
100.
OBJECTIVE: To determine the efficacy of shock wave lithotripsy (SWL) in anomalous kidneys. METHODS: From October 1990 to October 2002, 150 patients (93 men and 57 women) with anomalous urinary tracts, including 45 horseshoe kidneys, 57 duplex kidneys, 30 malrotated kidneys, 14 pelvic and four crossed ectopic kidneys were treated with SWL for urolithiasis at the Gazi University Faculty of Medicine. Shock wave lithotripsy was performed with Siemens Lithostar plus (Siemans, Erlanger, Germany) device and all procedures were carried under fluoroscopic control. Results: The mean shock wave number and intensity received by the patients was 3770 (range, 1380-4100) shocks and 18.4 (range, 16.1-19) kV per session, respectively. The minimum success rate was obtained in patients with lower calyceal (50%) followed by middle calyceal (60%) calculi. The stone-free rate decreased and the number of sessions per patient increased with increasing stone diameter (dm). In patients with a stone dm > 30 mm, only 34% could be stone-free, compared to a rate of 92% for calculi dm < 10 mm. The overall stone free rate at the third month was 68%. The best stone-free rates were obtained in patients with ureteral duplication (80.7%). The stone-free rates in horseshoe, malrotated, pelvic and crossed ectopic kidneys were found to be 66.7%, 56.7%, 57.2% and 25%, respectively. CONCLUSION: Shock wave lithotripsy might be an effective and minimally invasive treatment alternative in stone-bearing anomalous kidneys. The type of anomaly, stone burden and localization seem to be the main parameters effecting the treatment success.  相似文献   
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