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81.
The aim of this study is to assess the radiological outcome of conventional techniques versus computer-navigated surgery for total knee arthroplasty. Ninety patients with knee arthritis were prospectively randomized into 3 groups: conventional technique: extramedullary (EM) and intramedullary (IM) tibia guide versus computer navigation surgery (CAS). Two surgeons performed all procedures. Standardized long leg coronal and sagittal x-rays were evaluated by a blinded assessor. Our results showed that CAS had greater consistency and accuracy in implant placement. In the coronal view, 93.3% in the CAS group had better outcomes compared with EM (73.4%) and IM (60.0%). In the sagittal axis, 90.0% CAS also had better outcomes compared with EM (63.3%) and IM (76.7%). Computer-navigated total knee arthroplasty helps increase accuracy and reduce "outliers" for implant placement.  相似文献   
82.
Surgical correction of pectus excavatum (PE) has been well established since Ravitch's publication in 1949. However, Ravitch's procedure, even if modified, was associated with the relatively radical nature of the operation. The aim of this study was to report our early experience and results in treatment of PE by a novel less invasive surgical technique through a small skin incision. From 1998 to 2003, a novel surgical correction through a small transverse incision was performed for 11 patients with PE, including 9 males and 2 females. The mean age was 9.2 years (range, 3 to 17 years). The less invasive surgical technique consisted of a small transverse skin incision over the deepest part of the PE deformity, subcutaneous dissection to the margin of the depressed deformity, elevation of pectoralis musculature from the midline toward the lateral border of the operative field, subperichondrial resection of the short segment (1 to 2 cm) of the involved costal cartilages, detachment of the xiphoid process and elevation of the sternum with sharp or blunt dissection, retrosternal titanium miniplate strutting, placement of drainage tubes in the mediastinum or pleural spaces, and closure of the operative wound. No sternal osteotomy was performed in this series. The average length of the skin incision was 3.2 cm. The number of the resected cartilages varied from 3 to 6 ribs on each side. The average blood loss was 41 mL (range, 10 to 80 mL), and the operation time was 3.1 hours. The duration of hospitalization was 4.4 days on average. There was no surgical complication or mortality. All patients were satisfied with their cosmesis, and no migration of the retrosternal strut was found in chest radiographs until the date of analysis. This less invasive surgical technique, which did not require osteotomy, could be effectively performed through a small skin incision and was associated with steady recovery of chest wall deformity, as well as excellent cosmetic results.  相似文献   
83.
OBJECTIVE: The outcomes of simultaneous pancreas-kidney (SPK) transplantation with donor organs procured from donation after cardiac death (DCD) are compared with transplants performed with donor organs recovered from donation after brain death (DBD). SUMMARY BACKGROUND DATA: Concerns exist regarding the utilization of pancreata obtained from DCD donors. While it is known that DCD kidneys will have a higher rate of DGF, long-term functional graft survival data for DCD pancreata have not been reported. METHODS: A retrospective review of all DCD SPK transplants performed at a single center was undertaken. RESULTS: Patient, pancreas, and kidney survival at 5 years were similar between DCD and DBD organs. Pancreas function and outcomes were indistinguishable between the 2 modes of procurement. As expected, the DCD kidneys had an elevated rate of DGF, which had no significant long-term clinical impact. CONCLUSION: SPK transplantation using selected DCD donors is a safe and viable method to expand the organ pool for transplantation.  相似文献   
84.

Background  

The purpose of this study was to evaluate the pattern of disc herniation and to investigate the associated symptoms in cases of isthmic spondylolisthesis. It is well known that the pathogenesis of degenerative spondylolisthesis associates with disc degeneration, followed by facet laxity and ligamentum flavum hypertrophy, which result in severe spinal canal stenosis. But isthmic spondylolisthesis is known to have a different pathogenesis. In isthmic spondylolisthesis, pseudodisc bulging is easily identified, and canal stenosis is comparatively rare. Therefore, we propose that isthmic spondylolisthesis has a different pattern of disc herniation from degenerative spondylolisthesis. We studied the type, incidence of disc herniation and clinical symptoms related to isthmic spondylolisthesis.  相似文献   
85.

INTRODUCTION

There is a paucity of local data on the prevalence of blood transmitted infections (BTIs), such as hepatitis B, hepatitis C and human immunodeficiency virus (HIV) infections, among illicit drug users. This study aimed to examine the prevalence of BTIs among substance-dependent inpatients and identify the factors associated with BTIs.

METHODS

We conducted a retrospective case note analysis of 170 inpatients who had a history of substance dependence and were seen at the National Addictions Management Service, Singapore, between 1 June 2009 and 31 May 2010.

RESULTS

The majority of the 170 inpatients were male (88.2%) and Chinese (58.2%). The mean age of the patients was 43.1 years, and the main drug of abuse was opioids (86.5%). BTIs were found in 70 (41.2%) inpatients; the prevalence of hepatitis B, hepatitis C and HIV infections was 3.7%, 39.6% and 0%, respectively. Lifetime intravenous drug use, but not needle-sharing, was more common among inpatients who were positive for BTIs (p < 0.01). Logistic regression analysis showed that lifetime intravenous drug use (OR 4.3, 95% CI 1.7–10.8, p < 0.01) was the only significant predictor of BTI.

CONCLUSION

41.2% of the substance users seeking help were positive for at least one BTI. Lifetime intravenous drug users were found to be more than four times more likely to have a BTI. Early detection and prevention is essential to improve prognosis.  相似文献   
86.

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   
87.
Background/Purpose: Endothelin is a potent mediator of the cardiovascular and renal systems. Studies have found that endothelin has an important role in regulating cardiac function and renal perfusion in neonates who are suffering from endotoxic shock. The authors believe that blockade of the endothelin response during endotoxemia will have a beneficial effect on neonatal cardiac and renal functions. In this study the authors have examined the effects of tezosentan, a dual endothelin-receptor antagonist, on the cardiovascular and renal systems of neonatal piglets during endotoxemia. Methods: Thirteen piglets were subjected to endotoxic shock and divided into a fluid-therapy group that received 0.9% normal saline and a group that received tezosentan (1 mg/kg/h). Mean arterial pressure (MAP), heart rate (HR), and glomerular filtration rate (GFR) were plotted at baseline, 1, 2, and 3 hours. Cardiac index (CI), renal blood flow (RBF), systemic vascular resistance (SVR), and renal vascular resistance (RVR) were obtained at baseline, 1, and 3 hours after baseline. Results: (P [lt ] .05 for 3 hours versus baseline and tezosentan versus fluid). Although fluid therapy in endotoxemia had no significant effect on MAP and RVR, it significantly increased HR (139 [plusmn] 17 to 246 [plusmn] 17 beats/min) and SVR (0.08 [plusmn] 0.05 to 0.33 [plusmn] 0.09 mm Hg/mL/min) and decreased CI (407 [plusmn] 208 to 98 [plusmn] 13 mL/min/kg), RBF (1.84 [plusmn] 0.38 to 0.97 [plusmn] 0.34 mL/min/kg kidney), and GFR (0.20 [plusmn] 0.05 to 0.11 [plusmn] 0.04 mL/min/kg) at 3 hours. The use of tezosentan also significantly increased HR (130 [plusmn] 14 to 220 [plusmn] 31 beats/min), but unlike in the fluid therapy group, there was a significant fall in MAP (77 [plusmn] 10 to 54 [plusmn] 9 mm Hg) and RVR (1.92 [plusmn] 0.44 to 1.77 [plusmn] 0.64 mm Hg/mL/min) and a less severe decrease in CI (482 [plusmn] 188 to 176 [plusmn] 67 mL/min/kg) at 3 hours. SVR, RBF, and GFR were maintained. Conclusions: Endotoxic shock affected cardiac and renal functions in both treatment groups. Fluid therapy alone could not prevent a statistically significant fall in CI, RBF, and GFR or prevent the increase in HR and SVR. Endothelin antagonism with tezosentan resulted in a statistically significant fall in MAP and RVR from baseline, not seen in the fluid-therapy group. CI and RBF were significantly higher, and MAP, SVR, and RVR were significantly lower when compared with the fluid-therapy group at 3 hours. GFR also was maintained at baseline with tezosentan. During endotoxemia, endothelin antagonism maintained renal and cardiac functions better than with fluid therapy alone.  相似文献   
88.
BACKGROUND: Until recently, there has been no practical alternative to the use of calcineurin inhibitors (CIs) as primary immunosuppressants in lung transplantation (LTx) and heart transplantation (HTx). Sirolimus (SRL) is a novel powerful immunosuppressant without renal toxicity, a common post-transplant problem associated with CI therapy. METHODS: SRL was used in 20 LTx and 5 HTx recipients >90 days post-transplant, where serious renal impairment was limiting CI dosing. Patients started on 2 to 5 mg/day orally at a median of 1,185 days post-transplant. Dosage adjustments were made according to trough levels, toxicity and perceived efficacy. With SRL initiation, 48% ceased CI therapy and the remainder decreased their dose substantively. RESULTS: After 30 days, 4 of 5 dialyzed patients ceased dialysis and 15 of 20 patients with an elevated serum creatinine (Cr) (mean Cr 0.29 mmol/liter) improved their Cr. The direction of change in Cr at 30 days predicted longer term Cr. The starting Cr did not predict the 30-day or long-term value. There were two bouts of acute and one bout of chronic rejection. There were 35 infectious complications in 16 patients and 24 episodes of potential SRL-related toxicity in 17 patients. These events generally responded to dose reduction or temporary cessation and were level-related. Fifteen recipients presently remain on the drug. None of the 7 deaths could be directly related to toxicity. CONCLUSION: SRL is a useful alternative immunosuppressant, allowing significant CI withdrawal in transplant recipients with renal impairment. Whether the resulting improvement in Cr can be maintained in the long term probably depends on the balance between the extent of acute and chronic renal damage.  相似文献   
89.
The authors present a case of amyloid infiltration involving the trigeminal nerve that mimicked a malignant cavernous sinus tumor with perineural tumor infiltration. A 64-year-old man presented with trigeminal nerve numbness. Imaging revealed a plaque-like enhancing lesion along the right lateral cavernous sinus extending anteriorly into Meckel's cave and involving the proximal V2 and V3 branches of the trigeminal nerve. The patient underwent an extradural frontotemporal craniotomy with middle fossa exposure of the cavernous sinus to diagnose and treat the presumed malignant cavernous sinus tumor. A reddish mass involving the lateral dural wall of the cavernous sinus was resected. The gasserian ganglion, V2, and V3, the latter of which was biopsied, were enlarged. Permanent histopathological studies showed microscopic eosinophilic, amorphous material, which stained positive for Congo red, and an absence of neoplastic cells. The final diagnosis was amyloidoma. Thus, amyloidomas can involve the trigeminal nerve or ganglia and should be considered in the differential diagnosis of a cavernous sinus lesion mimicking a tumor. Patients may have symptomatic improvement of trigeminal neuropathy with resection of the amyloidoma outside the nerve capsule that is compressing the nerve, while resection of the lesion from within the capsule may result in permanent trigeminal nerve dysfunction.  相似文献   
90.
The authors present the case of a 43-year-old women who underwent a laparoscopic gastric bypass in 2003 for morbid obesity. They report that 2 years later, she had maintained significant weight loss, but had developed acute abdominal pain, followed by nausea and emesis. In the emergency room, she had diffuse tenderness, tachycardia, and leukocytosis. After initial resuscitation, a computed tomography was performed, which showed free air above the liver and thickened small bowel loops. She was brought emergently to the operating room for laparoscopy. At surgery, turbid fluid and inflamed small bowel loops were seen. A perforated marginal ulcer was discovered in the Roux limb, approximately 2 cm distal to the gastrojejunal anastomosis. The perforation was oversewn primarily and patched with omentum. The repair was tested by intraoperative endoscopy. A gastrostomy tube also was placed within the gastric remnant for enteral access. The patient did extremely well postoperatively, and had an uneventful postoperative course. She was discharged on postoperative day 4. The gastrostomy tube was removed at 1 month, and at this writing, she remains well since surgery. An upper endoscopy at 2 months was completely normal, and the Helicobacter pylori test results were negative. The gastric pouch had not significantly enlarged since initial surgery, as indicated by both endoscopy and barium study. Marginal ulcer is reported to be 0.6% to 16% after laparoscopic gastric bypass [1]. Etiologies include gastrogastric fistula, excessively large gastric pouch containing antral mucosa, H. pylori infection, nonsteroidal antiinflammatory use, and smoking [2]. Unfortunately, none of these applied to the reported patient. Because her exact etiology remains unknown, she at this writing continues to receive proton pump inhibitor therapy. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.  相似文献   
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