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51.

Purpose

The aim of our study was to follow the evolution over time of multifocal intraductal papillary mucinous neoplasms (IPMN) of the pancreatic duct side branches by means of magnetic resonance imaging (MRI).

Materials and methods

A total of 155 patients with multifocal IPMN of the side branches were examined with MRI and MR cholangiopancreatography (MRI/MRCP). Inclusion criteria were patients with ≥2 dilated side branches involving any site of the parenchyma; presence of communication with the main pancreatic duct and previous investigations by MRI/MRCP within at least six months. Median follow-up was 25.8 months (range, 12–217). Patients with a follow-up period shorter than 12 months (n=33) and those with a diagnosis of multifocal IPMN of the side branches without any follow-up (n=14) were excluded from the study. The final study population thus comprised 108 patients. A double, quantitative and qualitative, analysis was carried out. The quantitative image analysis included: number of dilated side branches in the head-uncinate process and body-tail; maximum diameter of lesions in the head-uncinate process; maximum diameter in the body-tail; maximum diameter of the main pancreatic duct in the head and body-tail. The qualitative image analysis included: presence of malformations or anatomical variants of the pancreatic ductal system; site of the lesions (head-uncinate process, body-tail, ubiquitous, bridge morphology); presence of gravity-dependent intraluminal filling defects; presence of enhancing mural nodules.

Results

At diagnosis, the mean number of cystic lesions of the side branches was 7.09. The mean diameter of the cystic lesions was 13.7 mm. The mean diameter of the main pancreatic duct was 3.6 mm. At follow-up, the mean number of cystic lesions was 7.76. The mean diameter of the cystic lesions was 13.9 mm. The mean diameter of the main pancreatic duct was 3.7 mm. Intraluminal filling defects in the side branches were seen in 18/108 patients (16.6%); enhancing mural nodules were seen in 3/108 patients (2.7%).

Conclusions

Multifocal IPMN of the branch ducts shows a very slow growth and evolution over time. In our study, only 3/108 patients showed mural nodules which, however, did not require any surgical procedure, indicating that careful nonoperative management may be safe and effective in asymptomatic patients.  相似文献   
52.
PURPOSE: There is growing interest among urologists on the need for decreasing pain during transrectal ultrasound (TRUS) guided prostate biopsy. MATERIALS AND METHODS: We performed a systematic MEDLINE search of clinical trials of any kind of anesthesia, analgesia or sedation during TRUS guided prostate biopsy published since 2000. We critically analyzed the impact of pain and discomfort associated with the procedure, the described methods for evaluating it and the different techniques that have been described. RESULTS: There is strong evidence in the current literature that patient tolerance and comfort during TRUS guided prostate biopsy can be improved by anesthesia/analgesia. What remains is the need to urge all urologists to introduce it in clinical practice as a routine part of the procedure, whatever the biopsy scheme. CONCLUSIONS: Of the various options periprostatic anesthetic infiltration has been shown to be safe, easy to perform and highly effective. It should be considered the gold standard at the moment, even if the optimal technique remains to be established. Further studies addressing this issue are warranted.  相似文献   
53.
There is increasing proof that organ preservation by machine perfusion is able to limit ischemia/reperfusion injury in kidney transplantation. This study was designed to compare the efficiency in hypothermic organ preservation by machine perfusion or cold storage in an animal model of kidney autotransplantation.
Twelve pigs underwent left nephrectomy after warm ischemic time; the organs were preserved in machine perfusion ( n  = 6) or cold storage ( n  = 6) and then autotransplanted with immediate contralateral nephrectomy. The following parameters were compared between the two groups of animals: hematological and urine indexes of renal function, blood/gas analysis values, histological features, tissue adenosine-5'-triphosphate (ATP) content, perforin gene expression in kidney biopsies, and organ weight changes were compared before and after preservation.
The amount of cellular ATP was significantly higher in organs preserved by machine perfusion; moreover, the study of apoptosis induction revealed an enhanced perforin expression in the kidneys, which underwent simple hypothermic preservation compared to the machine-preserved ones. Organ weight was significantly decreased after cold storage, but it remained quite stable for machine-perfused kidneys.
The present model seems to suggest that organ preservation by hypothermic machine perfusion is able to better control cellular impairment in comparison with cold storage.  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.

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   
56.
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   
57.
58.
BACKGROUND: The aim of the present study was to highlight the advantages of treatment of bile duct injury (BDI) occurring during cholecystectomy on the basis of a multidisciplinary cooperation of expert surgeons, radiologists, and endoscopists. METHODS: Sixty-six patients had major BDIs or short- or long-term failures of repair. BDI was diagnosed intraoperatively in 27 patients (40.9%) and postoperatively in 39 (59.1%) patients. Among referred patients, 30 had complications from bile leak, 15 from obstructive jaundice, and 20 from recurrent cholangitis. Two patients died from sepsis after delayed referral before repair was attempted. Eleven additional patients had minor BDIs with bile leak both with and without choleperitoneum. RESULTS: Of patients with major BDI, surgical repair was performed in 41 (64.1%). Postsurgical morbidity rate was 15.8%, and there was no mortality. The rate of excellent or good results after surgical repair was 78.0% (32 of 41 patients), and this increased to 87.8% (36 of 41 patients) by continuing treatment with stenting in postsurgical strictures. Biliary stenting alone was performed in 23 patients (35.9%), with excellent or good results in 17 (73.9%). More than 200 endoscopic and percutaneous procedures were performed for initial assessment, treatment of sepsis, nonsurgical repair, contribution to repair, and follow-up. Patients with minor BDIs underwent various combinations of surgical and endoscopic or percutaneous treatments, always with good results. CONCLUSIONS: A multidisciplinary approach was of paramount importance in many phases of treatment of BDI: initial assessment, treatment of secondary complications, resolution of sepsis, percutaneous stenting before surgical repair, dilatation of strictures after repair, final treatment in patients not repaired surgically, and follow-up.  相似文献   
59.
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   
60.
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