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91.
92.
Tissue temperature distribution plays a crucial role in the outcome of laser-induced thermotherapy (LITT), a technique employed for neoplasias removal. Since recent studies proposed LITT for pancreatic tumors treatment, assessment of temperature and of its effects around the laser applicator could be useful to define optimal laser settings. The aims of this work are temperature monitoring and measurement of ablated tissue volume in an ex vivo porcine pancreas undergoing double-applicator LITT. A three-dimensional numerical model is implemented to predict temperature rise and volumes of ablated tissue in treated pancreas. Experiments are performed to validate the model, with two modalities: (1) 12-fiber Bragg grating sensors are adopted to monitor the heating and cooling during LITT at several distances from the applicators tip, and (2) 1.5-T MR imaging is used to estimate the ablated volume. Experimental data agree with theoretical ones: at 2 mm from both applicators tips, the maximum temperature increase is approximately 60 °C downward from the tips, while it increases of about 40 °C and 30 °C, respectively, at the level and upward from the tips. This behavior occurs also at other distances, proving that the tissue downward from the tip is mostly heated. Furthermore, the estimated volume with MRI agrees with theoretical one (i.d., 0.91?±?0.09 vs. 0.95 cm3). The encouraging results indicate that the model could be a suitable tool to choose the optimal laser settings, in order to control the volume of ablated tissue.  相似文献   
93.

Background and purpose

Placement of flow-diverters across the ostia of major ICA branches carries a risk of arterial occlusion. We determined the rate of occlusion of the supraclinoid ICA branches and the related symptoms, following coverage with flow-diverters.

Materials and methods

A systematic search was performed in PubMed, MEDLINE, and EMBASE. We selected studies reporting treatments with flow-diverters in which the device was placed across the ostium of the OphtA, PcomA, or AchorA. Random-effects meta-analysis was used to pool the following outcomes: rate of arterial occlusion, diminished flow, incidence of related symptoms, factors associated with arterial occlusion.

Result

Twenty-one studies evaluating 1152 supraclinoid ICA branches were included in the meta-analysis. The incidence of OphtA occlusion and associated symptoms was 5.9% (95 CI%?=?3.1–8.6%) (incidence rate?=?6% per patient-year), and 0.8% (95% CI?=?0.1–1.4%) (incidence rate?=?0.8% per patient-year), respectively. Although asymptomatic in all cases, PcomA showed a higher occlusion rate (20.7%, 95% CI?=?8.9–32.4%) (incidence rate?=?19.5% per patient-year). AchorA was occluded in 1% (95% CI?=?0.3–2.4%) of cases, with approximately 1% (95% CI?=?0.4–2.3%) of transient neurological symptoms (incidence rate?=?0.96% per patient-year). There was a trend toward higher odds of arterial patency among arteries arising from the aneurysm (OR?=?2.94, P?=?0.06). Demographic factors and multiple stents were not associated with higher risk of arterial impairment. Adequate collateral circulation was reported in 94.5% of patients with arterial occlusion.

Conclusions

During aneurysm treatment, the ostium of the supraclinoid ICA branches can be covered with flow-diverter devices with low rates of neurological symptoms related to arterial occlusion.  相似文献   
94.

Introduction

The objective of this study was to present the outcomes of moderately hypofractionated helical intensity-modulated radiation therapy (HT) with/without simultaneous integrated boost (SIB) on fluorodeoxyglucose-positron emission tomography (FDG-PET) positive areas (gross tumor volume [GTV]-PET) for patients with progressive malignant pleural mesothelioma (MPM) after previous treatments.

Methods and Materials

From May 2006 to April 2014, 51 patients with a median age of 68.8 years (range, 38.6-82 years) were treated. There were 41 men and 10 women; 43 epithelioid MPM and 8 sarcomatoid, involving the left pleura in 25 patients and the right pleura in 26 patients. The initial stage was: I, 11 patients; II, 14 patients; III, 17 patients; and IV, 9 patients. Chemotherapy was prescribed for 46 patients, for 6 cycles (range, 0-18 cycles). Eighteen patients had pleurectomy/decortication, and 33 had talc pleurodesis. FDG-PET was used for target identification. A median dose of 56 Gy/25 fractions was prescribed to the involved pleura, and SIB to 62.5 Gy to GTV-PET was added in 38 patients.

Results

The median survival from diagnosis was 25.8 months (range, 8.4-99.0 months). One patient, treated with SIB, was alive at the October 2017 follow-up. Two cases of grade 5 radiation pneumonitis were registered. A GTV-PET ≤ 205 cc was predictive of late ≥ grade 2 lung toxicity, but also of better survival in stage III and IV disease: 5.9 versus 11.7 months (P = .04). A GTV-PET ≥ 473 cc was predictive of early death (P = .001).

Conclusions

Moderately hypofractionated, FDG-PET guided salvage HT in patients with progressive MPM after previous treatments showed acceptable toxicity and outcome results similar to adjuvant radiotherapy after pleurectomy/decortication, suggesting that the delay of radiotherapy is not detrimental to survival, and has the associated benefit of postponing inherent toxicity.  相似文献   
95.
96.
We report the follow-up of 47 patients with penile hypospadias who were treated by the Scuderi procedure between 1988 and 1998 at Sahlgrenska University Hospital, Göteborg, Sweden. Forty of the patients (85%) had had no previous operations, while the remaining seven had had meatotomy with chordectomy only, or an unsuccessful Dennis-Browne procedure. Hypospadias was distal in 35 (74%), mediopenile in 8 (17%), and proximal in 4 (9%); 21 (45%) showed signs of curvature. After a Scuderi urethroplasty one patient developed a fistula (2%) and 4 developed mild stenosis. The early success rate was therefore 42/47 (89%) and this later increased to 46/47 (98%) after non-surgical treatment of the stenoses. The results support the use of the Scuderi procedure for correction of primary and secondary penile hypospadias with a low complication rate.  相似文献   
97.
Background: Routine pathological examination can miss micro-metastatic tumor foci in the lymph nodes (LN) of patients with prostate cancer (PCa) that undergo radical prostatectomy and pelvic lymph node dissection (PLND). The aim of the present prospective study was to evaluate the impact of micrometastases assessed by serial section (SS), immunohistochemistry (IHC), and Real-time Polymerase Chain Reaction (RT-PCR) in patients undergoing radical prostatectomy with extended PLND. Materials and methods: 32 consecutive patients who underwent radical prostatectomy with extended PLND (obturator, internal/external and distal 2cm common iliac lymph-nodes (LN)) for intermediate (clinical T1c-T2 and PSA:10-20 ng/mL and clinical Gleason Score = 7) or high (clinical stage T3 or PSA>20 or clinical Gleason Score = 8-10) PCa were enrolled. The nodes were processed by the one uropathologist, both according to the routine pathological examination (analysis of the central section for 4 mm nodes or every 2 mm for LN>4 mm), which served as comparative method, both according to SS, IHC with antibodies against PSA and broad-spectrum Cytokeratins (BSCK), and quantitative RT-PCR targeting PSA, PSMA (PS Membrane Antigen), and Glucuronidase-S-Beta (GUSB) mRNA, that are over-expressed in prostatic cancer cells. Results: A total of 628 LN were analyzed, with a mean number of LN removed of 19.6 (SD = 7.2). Applying the routine pathological examination, 10 (31.2%) patients and 23 (3.9%) LN resulted positive for nodal involvement, with mean positive LN of 2.2 (SD = 1.4). After applying the SS and the molecular method of analysis (IHC and RT-PCR), micrometastases were found in 7 LN (SS showed micrometastases in 3 of them, IHC in 6 of them and RT-PCR in 7 of them); a total of 3 (9.3%) node-negative patients showed micrometastases at routine pathological examination (in 2 patients with RT-PCR and in 1 with IHC). Conclusions: The significance of micrometastases in PCa and the potential therapeutic role of PLND is not yet clarified, but the molecular analysis of the LN can detect a significant percentage of patients who harbor micro-metastatic PCa missed at routine pathological examination, and can enhance the accuracy of lymphadenectomy as a staging method.  相似文献   
98.
99.
BACKGROUND:Minimally invasive surgery has achieved worldwide acceptance in various fields, however, pancreatic surgery remains one of the most challenging abdominal pro-cedures. In fact, the indication for robotic surgery in pancre-atic disease has been controversial. The present study aimed to assess the safety and feasibility of robotic pancreatic resec-tion. METHODS: We retrospectively reviewed our experience of robotic pancreatic resection done in Sanchinarro University Hospital. Clinicopathologic characteristics, and perioperative and postoperative outcomes were recorded and analyzed. RESULTS: From October 2010 to April 2016, 50 patients underwent robotic-assisted surgery for different pancreatic pathologies. All procedures were performed using the da Vinci robotic system. Of the 50 patients, 26 were male and 24 female. The average age of all patients was 62 years. Operative time was 370minutes. Among the procedures performed were 16 pancreaticoduodenectomies (PD), 23 distal pan-createctomies (DP), 11tumor enucleations (TE). The mean hospital stay was 17.6 days in PD group, 9.0 days in DP group and 8.4 days in TE group. Pancreatic fistula occurred in 10 cases (20%), 2 after PD, 3 after DP, and 5 after TE. Four pa-tients had postoperativetransfusion in PD group and one in DP group. Conversion to open laparotomy occurred in four patients (8%). No serious intraoperative complications were observed. CONCLUSIONS:From our early experience, robotic pancre-atic surgery is a safe and feasible procedure. Further experi-ence and follow-up are required to confirm the role of robotic approach in pancreatic surgery.  相似文献   
100.
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