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31.
Introduction We used an experimental hip model to assess the mechanical stability of a hip prosthesis, and compared the femoral medullary canal preparation techniques of reaming and broaching.

Methods 15 pairs of cadaveric femora had a simulated replacement, the right femur with a reaming technique and the left with a broaching technique. Both femurs were radiographed to assess component positioning and cement mantle. The femurs were osteotomized 30 days after the procedure. The shear strength of the interface was studied at 4 different levels along an aluminum rod during push-out tests.

Results The overall mean value of the interface failure load was 15% lower with the reaming technique (6.5 kN for the reaming technique versus 7.7 kN for the broaching technique; p = 0.02).

Interpretation Broaching was superior to reaming for the preparation of the femoral canal, and should be used in order to increase primary stability. Further in vivo studies are required to account for factors such as intramedullary pressure, bleeding and surgical variations, which could not be accounted for in our study.  相似文献   
32.
100 multivisceral transplants at a single center   总被引:7,自引:0,他引:7       下载免费PDF全文
OBJECTIVE: The objective of this study was to summarize the evolution of multivisceral transplantation over a decade of experience and evaluate its current status. SUMMARY BACKGROUND DATA: Multivisceral transplantation can be valuable for the treatment of patients with massive abdominal catastrophes. Its major limitations have been technical and rejection of the intestinal graft. METHODS: This study consisted of an outcome analysis of 98 consecutive patients who received multivisceral transplantation at our institution. This represents the largest single center experience to date. RESULTS: The most common diseases in our population before transplant were intestinal gastroschisis and intestinal dysmotility syndromes in children, and mesenteric thrombosis and trauma in adults. Kaplan Meier estimated patient and graft survivals for all cases were 65% and 63% at 1 year, 49% and 47% at 3 years, and 49% and 47% at 5 years. Factors that adversely influenced patient survival included transplant before 1998 (P = 0.01), being hospitalized at the time of transplant (P = 0.05), and being a child who received Campath-1H induction (P = 0.03). Among 37 patients who had none of these 3 factors (15 adults and 22 children), estimated 1- and 3-year survivals were 89% and 71%, respectively. Patients transplanted since 2001 had significantly less moderate and severe rejections (31.6% vs 67.6%, P = 0.0005) with almost half of these patients never developing rejection. CONCLUSIONS: Multivisceral transplantation is now an effective treatment of patients with complex abdominal pathology. The incidences of serious acute rejection and patient survival have improved in the most recent experience. Our results show that the multivisceral graft seems to facilitate engraftment of transplanted organs and raises the possibility that there is a degree of immunologic protection afforded by this procedure.  相似文献   
33.

Background

Subintimal endovascular intervention has been used widely in the treatment of symptomatic superficial femoral artery (SFA) occlusion. The relative effectiveness of subintimal placement of a covered stent (CS) versus balloon-only subintimal angioplasty (SIA) remains uncertain.

Methods

We performed a retrospective cohort study of consecutive patients with symptomatic SFA occlusions (>15 cm) who underwent subintimal endovascular intervention, either CS or SIA, in a single institution. Primary patency was the primary outcome. Secondary outcomes included complication rates, freedom from re-intervention, and limb salvage rates. Patency was ascertained with followup duplex or clinically.

Results

We evaluated 57 patients in the SIA group and 31 patients in the CS group. At 1 year the SFA primary patency for the SIA and CS groups was 28% versus 75% (P < .001), whereas the primary assisted patency was 37% versus 84% (P < .001), respectively. Need for bypass was 13% versus 0% (P = .05) in the SIA and CS groups, respectively.

Conclusions

Placement of a covered stent improves patency after subintimal intervention for long SFA occlusion.  相似文献   
34.
Mycobacterial spindle cell pseudotumor (MSCP) is an extremely rare complication of mycobacterial infections. It has been reported to occur in various sites such as skin, lymph nodes, bone marrow, lungs, and spleen. This tumor-like lesion can be confused clinically as well as radiographically with dermatofibroma, nodular fasciitis, xanthogranuloma, and Kaposi's sarcoma.While this lesion is rare and has been previously reported to occur only in superficial skin, we emphasize its consideration and inclusion in the differential diagnoses when a deep soft tissue mass is complicated by symptoms of deep tissue infection secondary to abscess formation in immunocompromised hosts. Here, we present the clinical and radiologic findings of a case of MSCP involving the deep plantar sheaths.  相似文献   
35.
36.
Purpose  The aim of this study is to evaluate the effectiveness of 111In-DTPA-Phe1-octreotide infusions after selective catheterization of the hepatic artery in inoperable metastasised liver, sst2 receptor-positive neuroendocrine tumours due to the effect of 111In Auger electron emission, minimising in parallel the toxicity of non-target tissue. Methods  The average dose per session administered monthly to each patient (17 cases in total) was 6.3 ± 2.3 GBq. Repetitions did not exceed 12-fold, except in one case (15 sessions). Response assessment was classified according to the Response Evaluating Criteria in Solid Tumours. CT/MRI scans were performed as baseline before, during and after the end of treatment, and monthly ultrasound images for follow-up measurements. Toxicity (World Health Organization criteria) was measured using blood and urine tests of renal, hepatic and bone marrow function. Results  Complete response was achieved in one (5.9%) patient and partial in eight (47.0%), and disease stabilization in 3 (17.7%) patients; five (29.4%) did not respond. A 32-month median survival time was estimated in 12 (70.5%). Nine of these 12 surviving had a mean target diameter shrinkage from 144 ± 81 to 60 ± 59 mm. Grade 1 erythro-, leuko- and thrombo-cytopenia occurred in three (17.6%) cases. Conclusion  In unresectable metastatic liver lesions positive for somatostatin receptors repeated, transhepatic high doses of 111In-DTPA-Phe1-octreotide show an effective therapeutic outcome. Given the locoregional modality character of the administration technique plus the extremely short range of 111In Auger and internal conversion electrons emission, no nephro-, liver- or myelo-toxicity has so far been observed.  相似文献   
37.

Purpose

To compare the accuracy of ultrasonography and magnetic resonance imaging in the detection of rotator cuff tears.

Materials and methods

Ninety-six patients with clinically suspected rotator cuff pathology underwent ultrasonography and magnetic resonance imaging of the shoulder. The findings in 88 patients were compared with arthroscopy or open surgery.

Results

Full-thickness tear was confirmed in 57 cases, partial-thickness tear in 30 cases and degenerative changes without tear in 1. In all 57 cases of full-thickness tear and in 28 out of 30 cases of partial-thickness tear the supraspinatus tendon was involved. The accuracy in the detection of full-thickness tears was 98 and 100% for ultrasonography and magnetic resonance imaging, respectively. The accuracy in the detection of bursal or articular partial-thickness tears was 87 and 90% for ultrasonography and magnetic resonance imaging, respectively.

Conclusions

In experienced hands ultrasonography should be considered as an accurate modality for the initial investigation of rotator cuff, especially supraspinatus, tears.  相似文献   
38.
Objective  Percutaneous transluminal coronary angioplasty is a well-established therapeutic method in selected patients with coronary artery disease. The aim of this study was to assess the incremental prognostic value of technetium-99m (99mTc)-tetrofosmin myocardial gated-single- photon emission computed tomography (SPECT) in asymptomatic patients after coronary artery stenting. Methods  A total of 246 consecutive patients (aged 55.5 ± 8.2 years, 182 men) participated in the study with a median follow-up of 9.5 years (interquartile ra 5.8–10.5 years). All patients underwent exercise gated-SPECT myocardial imaging within 5–7 months. Myocardial scintigrams were performed using 99mTctetrofosmin, and were evaluated calculating the summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS) indexes. Cardiovascular death and non-fatal myocardial infarction were considered as hard cardiac events, and late revascularization (>3 months after myocardial SPECT) procedures as soft events. Receiver-operating characteristic (ROC) analysis was used to test the prognostic ability of SSS and SDS for cardiac events. Cox proportional hazards models were used to evaluate the incremental value of SPECT variables. Results  Cardiac death occurred in 12 (4.9%) patients and non-fatal myocardial infarction in 20 (8.1%) patients. In addition, 60 (24.4%) patients underwent a late revascularization procedure. Using ROC analysis the optimal cut-offs of SSS (AUC = 0.94; 95% CI 0.92–0.97) and SDS (AUC = 0. 76; 95% CI 0.70–0.82) for the prediction of cardiac events were 10 and 1.7, respectively. Multiple Cox regression analyses revealed that SSS > 10 (HR = 24.2; 95% CI 7.44–78.79) and SDS > 1.7 (HR = 2.72; 95% CI 1.23–6.00) provided incremental prognostic value over clinical and exercise test data for the composite end points of any cardiac event. Conclusions   99mTc-tetrofosmin myocardial gated- SPECT, performed 6 months post-percutaneous coronary intervention (PCI), provides incremental prognostic information for the prediction of cardiac events in asymptomatic patients after PCI.  相似文献   
39.
Abstract   Background: Aortic arch surgery is impossible without the temporary interruption of brain perfusion and therefore is associated with high incidence of neurologic injury. The deep hypothermic circulatory arrest (HCA), in combination with antegrade or retrograde cerebral perfusion (RCP), is a well-established method of brain protection in aortic arch surgery. In this retrospective study, we compare the two methods of brain perfusion. Materials and Methods: From 1998 to 2006, 48 consecutive patients were urgently operated for acute type A aortic dissection and underwent arch replacement under deep hypothermic circulatory arrest (DHCA). All distal anastomoses were performed with open aorta, and the arch was replaced totally in 15 cases and partially in the remaining 33 cases. Our patient cohort is divided into those protected with antegrade cerebral perfusion (ACP) (group A, n = 23) and those protected with RCP (group B, n = 25). Results: No significant difference was found between groups A and B with respect to cardiopulmonary bypass-time, brain-ischemia time, cerebral-perfusion time, permanent neurologic dysfunction, and mortality. The incidence of temporary neurologic dysfunction was 16.0% for group A and 43.50% for group B (p = 0.04). The mean extubation time was 3.39 ± 1.40 days for group A and 4.96 ± 1.83 days for group B (p = 0.0018). The mean ICU-stay was 4.4 ± 2.3 days for group A and 6.9 ± 2.84 days for group B (p = 0.0017). The hospital-stay was 14.38 ± 4.06 days for group A and 19.65 ± 6.91 days for group B (p = 0.0026). Conclusion: The antegrade perfusion seems to be related with significantly lower incidence of temporary neurological complications, earlier extubation, shorter ICU-stay, and hospitalization, and hence lower total cost.  相似文献   
40.
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