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981.

Background  

Long-term survival for combined aortic and mitral valve replacement appears to be determined by the mitral valve prosthesis from our previous studies. This 21-year retrospective study assess long-term outcome and durability of aortic valve replacement (AVR) with either concomitant mitral valve replacement (MVR) or mitral valve repair (MVrep). We consider only a single mechanical prosthesis.  相似文献   
982.

Background/Purpose

Antenatally detected liver cysts are rare; their diagnostic accuracy is unknown, and their management is controversial. This study assessed the natural history of these lesions.

Methods

We conducted a retrospective review of infants with isolated intrahepatic cysts that were detected antenatally. Data are expressed as median (range).

Results

Fifteen infants presented during the period 1991-2004 with an antenatally detected liver cyst. Their gestational age at detection was 22 (18-34) weeks, and the maximum diameter of their cyst was 23 (10-120) mm. Serial scans, which were performed in 9 fetuses, showed cyst enlargement in 5 cases, diminution in 1 case, and no change in 3 cases. In utero percutaneous aspiration was required in 1 infant. Three infants underwent postnatal surgery. One fetus (postfetal intervention) had a subtotal excision of a large subcapsular cyst filling the abdominal cavity on day 2. Another infant required partial excision and marsupialization (complex cyst arising from segment IV) at 5 months, and a third infant underwent a cyst cholecystostomy at 4 months. Postnatal investigations (including hepatic scintigraphy) suggested that the remaining lesions were either simple parenchymal (n = 10) or isolated intrahepatic choledochal (ie, type V; n = 2) cysts. The median follow-up for these patients was 44 (27-167) months. Serial postnatal ultrasonography showed cyst diminution in 4 cases, an enlargement in 1 case, and no dimensional change in 7 cases.

Conclusions

Most antenatally detected liver cysts appear to be simple and of parenchymal origin and do not require fetal intervention. Their postnatal history is variable, but regression without treatment is seen in most cases.  相似文献   
983.
Delay in the diagnosis of esophageal atresia (EA) is rare. We present a child with EA and distal tracheoesophageal fistula who was diagnosed 9 days from birth after a contrast study performed at the referring hospital. This article aims to highlight the potential hazards of using contrast to diagnose EA.  相似文献   
984.

Background

The management of children with main pancreatic duct injuries is controversial. We report a series of patients with pancreatic trauma who were treated using minimally invasive techniques.

Methods

Retrospective review of children with pancreatic trauma treated at a UK tertiary referral institution between 1999 and 2004.

Results

Fifteen children (11 boys) were admitted with pancreatic trauma. Twelve (80%) were less than 50th centile for body weight. Contrast-enhanced computed tomography (CT) scans were used to define organ injury, supplemented by magnetic resonance cholangiopancreatography (MRCP) in 7. Twelve (80%) underwent diagnostic endoscopic retrograde cholangiopancreatography (ERCP) with a median time after injury of 11 (range, 6-29) days. The degree of pancreatic injury was defined by ERCP and CT/MRCP as grade II (n = 2), grade III (n = 4), grade IV (n = 9) (American Association for the Surgery of Trauma grades). Nine children had a transductal pancreatic stent inserted endoscopically. Computed tomography/ultrasound-guided drainage was performed in 4 children for acute fluid collections. Two children later underwent endoscopic cyst-gastrostomy, one of whom later required conversion to an open cyst-gastrostomy.

Conclusion

Body habitus may predispose to pancreatic duct trauma. Contrast-enhanced CT scan (and MRCP) should dictate the need for ERCP. Transductal pancreatic stenting allows internal drainage of peripancreatic collections and may reestablish duct continuity, although a proportion still requires percutaneous or endoscopic cyst-gastrostomy drainage. Open surgery for pancreatic trauma should now be an exception.  相似文献   
985.

Background

In the United States, cholesterol stones account for 70% to 95% of adult gallstones and black pigment stones for most of the remainder. Calcium carbonate stones are exceptionally rare. A previous analysis of a small number of pediatric gallstones from the north of England showed a remarkably high prevalence of calcium carbonate stones. The aims of this study were to analyze a much larger series of pediatric gallstones from our region and to compare their chemical composition with a series of adult gallstones from the same geographic area.

Methods

A consecutive series of gallbladder stones from 63 children and 50 adults from the north of England were analyzed in detail using Fourier transform infrared microspectroscopy. Demographic and clinical data were collected on all patients. The relative proportions of each major stone component were assessed: cholesterol, protein and calcium salts of bilirubin, fatty acids, calcium carbonate, and hydroxyapatite.

Results

Thirty-nine (78%) adults had typical cholesterol stones, 7 (14%) had black pigment bilirubinate stones, and only 2 (4%) had calcium carbonate stones. In contrast, 30 (48%) children had black pigment stones, 13 (21%) had cholesterol stones, 15 (24%) had calcium carbonate stones, 3 (5%) had protein dominant stones, and 2 (3%) had brown pigment stones. In children, cholesterol stones were more likely in overweight adolescent girls with a family history of gallstones, whereas black pigment stones were equally common in boys and girls and associated with hemolysis, parenteral nutrition, and neonatal abdominal surgery. Calcium carbonate stones were more common in boys, and almost half had undergone neonatal abdominal surgery and/or required neonatal intensive care.

Conclusion

The composition of pediatric gallstones differs significantly from that found in adults. In particular, one quarter of the children in this series had calcium carbonate stones, previously considered rare. Geographic differences are not the major reason for the high prevalence of calcium carbonate gallstones in children.  相似文献   
986.

Purpose

Continuous monitoring tools can be used to monitor surgical outcomes over time. We illustrate the use of CUmulative SUM (CUSUM) charts in monitoring outcomes of Kasai portoenterostomy for treatment of biliary atresia at a supraregional unit.

Methods

Data on 57 consecutive infants who underwent a Kasai portoenterostomy performed by a single surgeon between June 1994 and June 2006 were collected. A procedure was defined as successful if clearance of jaundice (plasma bilirubin level <20 μmol/l) was achieved within 6 months of surgery. We applied cumulative observed-minus-expected, sequential probability ratio test (SPRT), and zero-resetting SPRT CUSUM charts and compared the results with those of standard aggregate data analyses. An expected failure rate of 43.0%, based on the national average failure rate, was used.

Results

The failure rate observed after 57 operations was 29.8%. The zero-resetting SPRT chart indicated a lower-than-expected failure rate earlier than did the aggregate data analyses and any of the other continuous monitoring techniques.

Conclusions

The CUSUM chart method provides ongoing feedback that can be used for continuous monitoring of the outcome of a procedure to ensure that standards of care are maintained. Its use as a routine monitoring tool in pediatric surgery deserves wider recognition.  相似文献   
987.
Beta-cell apoptosis appears to represent a key event in the pathogenesis of type 1 diabetes. Previous studies have demonstrated that administration of the serine proteinase inhibitor alpha1-antitrypsin (AAT) prevents type 1 diabetes development in NOD mice and prolongs islet allograft survival in rodents; yet the mechanisms underlying this therapeutic benefit remain largely unclear. Herein we describe novel findings indicating that AAT significantly reduces cytokine- and streptozotocin (STZ)-induced beta-cell apoptosis. Specifically, strong antiapoptotic activities for AAT (Prolastin, human) were observed when murine insulinoma cells (MIN6) were exposed to tumor necrosis factor-alpha. In a second model system involving STZ-induced beta-cell apoptosis, treatment of MIN6 cells with AAT similarly induced a significant increase in cellular viability and a reduction in apoptosis. Importantly, in both model systems, treatment with AAT completely abolished induced caspase-3 activity. In terms of its activities in vivo, treatment of C57BL/6 mice with AAT prevented STZ-induced diabetes and, in agreement with the in vitro analyses, supported the concept of a mechanism involving the disruption of beta-cell apoptosis. These results propose a novel biological function for this molecule and suggest it may represent an effective candidate for attempts seeking to prevent or reverse type 1 diabetes.  相似文献   
988.
The combination of improved resection, stabilization, and fusion techniques allows for more aggressive removal of malignant spinal tumors with acceptable mortality and morbidity. Thirty consecutive patients with primary sarcomas of the mobile spine, who were operated on at the authors' institution from January 1970 to December 2000, were included in the current study. Demographic information, tumor location, type of resection, resection margins, local recurrence, and overall survival data were retrieved and analyzed. Treatment consisted of en bloc resection in 12 patients (40%) and piecemeal resections in 18 patients (60%). The resection was classified as wide in seven patients (23.3%), marginal in three patients (10%), and intralesional in 20 patients (66.7%). Pathology reports showed tumor-free resection margins in 12 patients (40%). In the remaining 18 patients (60%), resection margins were positive and resulted in a fivefold increase in the risk of a local recurrence. Ninety-two percent of the patients with local recurrence died of sequelae associated with the local recurrence. Primary sarcomas of the mobile spine in certain cases, can be removed completely with tumor-free resection margins. En bloc resection with tumor-free margins provides substantial improvement in overall survival.  相似文献   
989.
PURPOSE: The endovascular approach to external iliac artery (EIA) disease extending into the common femoral artery (CFA) has been avoided because of problems with stent placement across the inguinal ligament. Surgical treatment for this disease distribution includes extensive endarterectomy or bypass procedures or both. We report our initial experience with a combined open and endovascular approach to these patients. METHODS: We performed a retrospective analysis of all patients who underwent intraoperative EIA stenting after CFA endarterectomy/patch angioplasty between 1997 and 2000. Stents were positioned to end at the proximal endarterectomy endpoint, without crossing the inguinal ligament. Technical success, hemodynamic success, and clinical success were determined according to Society of Vascular Surgery/International Society of Cardiovascular Surgery criteria. Life-table analysis was performed for patency. RESULTS: Thirty-four patients (mean age, 68 years; 23 male, 11 female) had combined endovascular and open treatment of iliofemoral occlusive disease. Indications were claudication in 41% and critical limb ischemia in 59%. Femoral reconstruction included endarterectomy with patch angioplasty in all patients. EIA stent deployment incorporated the stenotic iliac segment and the proximal endpoint of the endarterectomy in all patients. Four patients (12%) also needed common iliac angioplasty at the same time for proximal iliac disease, and 14 patients (41%) also needed distal revascularization for associated femoropopliteal or tibial disease. Technical success and hemodynamic success were achieved in 100% of patients. Clinical success was achieved in 97% of patients. The mean postoperative increase in ankle-brachial index in patients with inflow procedures only was 0.36 (range, 0.1 to 0.85). The overall complication rate was 15%. With a mean follow-up period of 13 months (range, 0.5 to 28 months), 1-year primary patency and primary-assisted patency rates were 84% and 97%, respectively. No perioperative mortality was seen. CONCLUSION: EIA stenting as an adjunct to CFA endarterectomy/patch angioplasty allows for more localized surgery than conventional bypass. This approach also allows a better interface between the stent and endarterectomy than staged preoperative stenting. Technical success and early patency rates are excellent.  相似文献   
990.
BACKGROUND: The purpose of this retrospective study was to report the results, after a minimum of 18.5 years of follow-up, in a consecutive series of total hip arthroplasties performed with an alumina-on-alumina combination. METHODS: One hundred and eighteen consecutive total hip arthroplasties were performed in 106 patients between 1979 and 1980. The prostheses combined a 32-mm alumina head and an all-alumina socket. Both components were cemented in eighty-five hips, both components were implanted without cement in twenty-nine, and only the stem was cemented in four. The mean age of the patients at the time of the index arthroplasty was 62.2 years (range, thirty-two to eighty-nine years). RESULTS: At the 18.5 to 20.5-year follow-up evaluation, forty-five patients (fifty-one hips) were alive and had not had a revision, twenty-five patients (twenty-five hips) had undergone revision of one or both components, twenty-seven patients (thirty hips) had died, and nine patients (twelve hips) had been lost to follow-up. The mean Merle d'Aubigné hip score (and standard deviation) was 16.2 +/- 1.8 points at the latest follow-up evaluation. The rate of survival at twenty years, with revision for any reason as the end-point, was 85.6% for the cementless cups compared with 61.2% for the cemented cups and 84.9% for the cementless stems compared with 87.3% for the cemented stems. Wear of the prosthetic components was undetectable on plain radiographs. Periprosthetic cystic or scalloped lesions requiring the use of allograft bone during revision were present in three of the twenty-five revised hips. In addition, seven hips had moderate acetabular osteolysis treated with a 4-mm-larger cup. No fracture of the alumina socket or head was recorded. The mean acetabular wear rate in this series was <0.025 mm/yr. CONCLUSION: With the alumina-on-alumina total hip arthroplasty, minimal wear rates and limited osteolysis can be expected up to twenty years after the operation, provided that sound acetabular component fixation is obtained.  相似文献   
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