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51.
Annals of Nuclear Medicine - [18F] fluorodeoxyglucose positron emission tomography/computed tomography ([18F] FDG-PET/CT) is used for diagnosis, staging, response assessment and prognosis...  相似文献   
52.

Background

Rhinoplasty and rhinoseptoplasty are very important and complex surgical procedures because the nose plays a pivotal aesthetic role in the face and an important functional role in breathing. Mild bulbous, plunging, undefined tips are very common, and tip refining and repositioning often are required surgical procedures.

Methods

For 97 selected patients, the authors performed their personal technique consisting of a transcartilaginous approach, incomplete vertical interruption, and retrograde undermining of the lower lateral cartilages to improve tip projection and definition. The five aspects analyzed were nasal tip symmetry, nostril symmetry, tip projection, tip definition, and appearance of the nasal tip only. Each parameter was assessed using pre- and postoperative quantification according to a visual analog scale. Postoperative evaluation was performed during a mean follow-up period of 1?year.

Results

The results at 1?year showed high rates of improvement in tip definition (mean, 7.9?±?2.4) and nasal tip only evaluation (mean, 6.5?±?3.1). The patients reported an improvement in nasal tip symmetry (mean, 4.2?±?3.2), nostril symmetry (mean, 4.5?±?4.1), and tip projection (mean, 5.8?±?2.9).

Conclusions

This simple, safe, and effective technique is proposed for mild bulbous, plunging, undefined, and hypoprojected tips.  相似文献   
53.
We describe our technique for preservation of the smooth muscular internal (vesical) sphincter and proximal urethra during radical retropubic prostatectomy. The first steps of the prostatectomy reflect the standard retropubic prostatectomy; whereas for the final phases, the procedure continues in an anterograde manner with incision of the fibers of the detrusor muscle at the insertion of the ventral surface of the base of the prostate. At this level, the inner circular muscle of the bladder neck forms a sphincteric ring of smooth muscle that covers the longitudinally‐oriented smooth muscle component of the urethra that extends distally to the verumontanum; these two proximal structures represent the internal sphincter that envelops and locks the proximal urethra. A blunt dissection is continued until the ring‐shaped vesical sphincter is separated from the prostate and the longitudinally‐oriented smooth muscle component of the urethral musculature is identified. The base of the prostate is then gently separated from the urethra and from the bladder until the maximal length of the urethral musculature is isolated and preserved. Finally, a urethra‐urethral anastomosis is carried out and the ventral stitches are placed through the circular fibres of the bladder neck. In all cases we carry out circumferential biopsies of the proximal urethra and of the base of the prostate. The described technique is a feasible and safe method for preservation of the internal urethral sphincter. Despite the enthusiasm regarding our positive functional results, further studies with larger series are required to confirm these findings.  相似文献   
54.
Radiofrequency (RF)-assisted thermal ablation has been used with increasing frequency for unresectable hepatic tumors. This new approach employs RF energy to coagulate the liver at the hepatic resection line after which hepatic resection is performed with the use of a common scalpel. This procedure was used in three patients with hepatocellular carcinoma and in five patients with colorectal metastasis to the liver. These eight patients underwent a total of two left bisegmentectomies, three segmentectomies, and seven wedge resections. Mean operative time was 220 minutes. A mean of 78 sessions of RF-assisted ablation were required for these resections. Mean blood loss was 46 ml; no device other than RF ablation was required to obtain hemostasis. None of the patients needed a blood transfusion. Preoperative hemoglobin was 12.8 gm/dl and postoperative hemoglobin was 11.3 gm/dl. There were no perioperative deaths. Postoperative complications occurred in two patients: a liver abscess in one and heart failure in the other. The mean hospital stay was 9.4 days. This new approach, integrated with other techniques, reduces blood loss and coagulates the margins of resection during liver surgery. This new technique has two limitations: (1) it cannot be applied near main portal pedicles, and (2) it requires a long operative time. The best indication for this technique is when segmentectomy is required in patients with cirrhosis. Its role in major hepatic resections has yet to be determined. Further progress in the development of thermal ablation techniques and experience gained during the learning curve should help reduce the operative time, thereby improving the safety and efficacy of this procedure. Presented at the Third International Meeting, "Hepatocellular Carcinoma: Eastern and Western Experience," Lodi, Italy, November 21–22, 2002.  相似文献   
55.
Twenty-five percent of patients undergoing surgery for acute complicated diverticulitis represent emergencies. This condition is currently treated by colonic resection with primary anastomosis with or without colostomy, or by a Hartmann operation. We report on our experience with 52 consecutive patients with generalized peritonitis (8 cases), peri- and paracolonic abscesses (19 cases), severe pelvic abscesses (12 cases) and multiple abscesses with visceral fistulas (13 cases). All patients had emergency surgery. In 50/52 patients (96.2%) we performed a colonic resection with primary anastomosis using a mechanical stapler and in 2/52 a Hartmann operation. The overall mortality rate was 5.8%. The morbidity rate was 22% with 9 anastomotic leakages. A diverting colostomy was constructed in 16 patients and opened in only 8 patients. In 4 cases a parastomal hernia occurred after late closure and reduction of the colostomy. This data suggest that colonic resection with primary anastomosis, even without colostomy, is a safe procedure for the emergency treatment of acute complicated diverticulitis.  相似文献   
56.
Regenerative medicine promises to meet two of the most urgent needs of modern organ transplantation, namely immunosuppression‐free transplantation and an inexhaustible source of organs. Ideally, bioengineered organs would be manufactured from a patient's own biomaterials—both cells and the supporting scaffolding materials in which cells would be embedded and allowed to mature to eventually regenerate the organ in question. While some groups are focusing on the feasibility of this approach, few are focusing on the immunogenicity of the scaffolds that are being developed for organ bioengineering purposes. This review will succinctly discuss progress in the understanding of immunological characteristics and behavior of different scaffolds currently under development, with emphasis on the extracellular matrix scaffolds obtained decellularized animal or human organs which seem to provide the ideal template for bioengineering purposes.  相似文献   
57.

Purpose

To validate and compare the values of “MIC” and “trifecta” as predictors of operated kidney functional preservation in a multi-institutional cohort of patients undergoing minimally invasive PN.

Methods

We retrospectively reviewed records of consecutive cases of minimally invasive PN performed for cT1 renal masses in 4 centers from 2009 to 2013. Inclusion criteria consisted of availability of a renal scan obtained within 2 weeks prior to surgery and follow-up renal scan 3–6 months after the surgery. The primary endpoint of the study was to compare the degree of ipsilateral renal function preservation assessed by MAG3 renal scan in relation to achievement of MIC and trifecta.

Results

Total of 351 patients met our inclusion criteria. The rates of trifecta achievement for cT1a and cT1b tumors were 78.9 and 60.6 %, respectively. The rate of MIC achievement for cT1a tumors and cT1b tumors was 60.3 and 31.7 %, respectively. On multivariable linear regression model, only the degree of tumor complexity assessed by R.E.N.A.L nephrometry score [coefficient B ?1.8 (?2.7, ?0.9); p < 0.0001] and the achievement of trifecta [coefficient B 6.1 (2.4,9.8); p = 0.014] or MIC (coefficient B 7.2 (3.8,0.6); p < 0.0001) were significant clinical factors predicting ipsilateral split function preservation.

Conclusions

Achievement of both MIC and “trifecta” is associated with higher proportion of split renal function preservation for cT1 tumors after minimally invasive PN. Thus, these outcome measures can be regarded not only as markers of surgical quality, but also as reliable surrogates for predicting functional outcome in the operated kidney.
  相似文献   
58.

Purpose

The mesenteric to left portal vein bypass (MLPVB) has been successfully used to treat extrahepatic portal vein obstruction (EHPVO) in children. We examined the effect of failed prior surgical or radiological procedures intended to treat complications of portal hypertension on the success rate of subsequent MLPVB surgery.

Methods

Sixty-two patients younger than 18 years with EHPVO underwent MLPVB between 1997 and 2006. Children were divided into 3 groups: those with no prior surgery related to portal hypertension, those with prior portosystemic shunts, and those with either splenectomy or mesenteric vascular embolization procedures. The effect of prior procedures on the patency rate of the MLPVB was then examined.

Results

Of 62 children, 11 (17.7%) had significant procedures to treat symptoms of portal hypertension: 6 had at least 1 portosystemic shunt attempt, 3 had isolated splenectomy, and 2 had embolization of the splenic artery or coronary and peripancreatic varices. Patients with previous portal hypertension surgery were significantly older and larger than those with no surgery. Patients with no prior interventions had a significantly higher MLPVB patency rate (88.2%, 45/51) than those with no prior interventions (63.6%, 7/11). Prior splenectomy alone was not found to adversely affect MLPVB. Patients with prior embolization procedures or unsuccessful shunts had significantly poorer successful outcomes (0% and 66.7%) than those with no prior interventions (88.2%; P < .005).

Conclusions

The results demonstrate that prior portosystemic shunts or mesenteric embolizations have a deleterious effect on outcome after MLPVB and should be avoided whenever possible. This study suggests that patients with symptomatic EHPVO should undergo MLPVB as a primary intervention rather than as a rescue procedure to optimize MLPVB patency.  相似文献   
59.
The laparoscopic approach has represented a major step forward in general and emergency surgery. Its application in the emergency setting still raises a number of concerns that limit its more widespread use. To assess the true scope of laparoscopic surgery in the acute abdominal setting, we retrospectively evaluated our experience. From February 2003 to June 2007, 314 patients underwent an emergency laparoscopic operation, for low abdominal pain (193 patients), acute cholecystitis (78 patients), bowel obstruction (18 patients), diffuse peritonitis (16 patients), blunt abdominal trauma (6 patients), and acute pancreatitis (3 patients). Laparoscopy yielded a good diagnostic definition in all cases. The conversion rate was 16.6% (52 patients). Mean operative time was 63 +/- 29 minutes. The general major morbidity rate was 1.5% (4 patients) and the mortality rate was 0.4% (1 pt.). The laparoscopic approach in patients with abdominal emergencies is a useful tool that yields a reliable diagnostic definition in uncertain cases and allows minimal access treatment of the causative disease in the majority of cases.  相似文献   
60.
The concept of femoroacetabular impingement (FAI) has, in a relatively short time, come to the forefront of orthopedic imaging. In just a few short years MRI findings that were in the past ascribed to degenerative change, normal variation, or other pathologies must now be described and included in radiology reports, as they have been shown, or are suspected to be related to, FAI. Crucial questions have come up in this time, including: what is the relationship of bony morphology to subsequent cartilage and labral damage, and most importantly, how is this morphology related to the development of osteoarthritis? In this review, we attempt to place a historical perspective on the controversy, provide guidelines for interpretation of MRI examinations of patients with suspected FAI, and offer a glimpse into the future of MRI of this complex condition. J. Magn. Reson. Imaging 2015;41:558–572. © 2014 Wiley Periodicals, Inc.  相似文献   
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