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991.
Bisphosphonate use has declined dramatically in recent years, partly because of fear of rare side effects like atypical femur fractures (AFFs). It is therefore desirable to have a diagnostic method to identify those at risk of AFF to prevent this serious complication. We compared trabecular microarchitecture and hip geometry between 30 patients with AFF and 141 controls of similar age and sex, using bisphosphonates. Trabecular bone score (TBS) and hip structural analysis (HSA) were used to assess trabecular microarchitecture and macroscopic hip geometry from dual-energy X-ray absorptiometry images of the lumbar spine and hip, respectively. General characteristics, TBS, and HSA were compared between patients with AFF and controls using Student's t tests and chi-square statistics. Associations between AFF and TBS and femur geometric characteristics by HSA were adjusted for sex, age, height, weight, ethnicity, duration of bisphosphonate use, and glucocorticoid use. Additionally, the analysis of TBS was adjusted for lumbar spine bone mineral density and the time difference between dual-energy X-ray absorptiometry scanning and the diagnosis of AFF. Patients with AFF had significantly higher body mass index than controls, had used bisphosphonates longer, and glucocorticoids and proton pump inhibitors more frequently. Sex-specific T-score was significantly higher in patients with AFF at the lumbar spine (p?=?0.004), but not at the femoral neck (p?=?0.190) after adjustment for age, height, and weight. TBS did not differ significantly between patients with AFF and controls. Neither neck shaft angle nor any geometric variables at the femoral shaft measured by HSA differed between patients with AFF and controls. At the narrow neck, patients with AFF had lower buckling ratio and higher centroid position, consistent with a lower risk of classical fragility hip fractures. The findings at narrow neck and higher bone mineral density might be explained by the fact that the majority of patients with AFF used bisphosphonates to prevent glucocorticoid-induced osteoporosis. Based on our results, TBS and HSA do not appear to have value in detecting patients at risk of AFF.  相似文献   
992.
993.
Background: Life-threatening small bowel obstruction (SBO) after Roux-en-Y gastric bypass can present with surprisingly minimal laboratory and plain x-ray findings. Based on a 10-year (1994-2003) experience of 1,409 open distal gastric bypasses, we present clinical and radiological findings in 29 patients with unusual forms of bowel obstruction. Methods: A retrospective chart review was conducted. A radiologist experienced in reviewing these in gastric bypass patients reviewed all computed tomography (CT) scans. Results: CT findings: The normal appearance and 7 recurring patterns of small bowel obstruction were identified. These include: 1) intussusception, 2) internal hernia through Petersen's space, 3) through Petersen's space and the mesenteric defect at enteroenterostomy, 4) through the mesenteric defect from the entero-enterostomy, 5) isolated biliary limb obstruction, 6) segmental non-anastomotic ischemia, and 7) internal hernia through bands. Clinical findings: 1 had peritonitis, and 1 had free air on plain film. WBC count was normal in 20/27 patients (74%) including 5/6 (83%) with dead bowel. 9/14 patients (62%) had "non-specific" findings on x-rays. 7 of these had an internal hernia (2 with volvulus and 2 with dead bowel), 1 had biliopancreatic limb obstruction, and 1 had peritonitis. Conclusion: Patients with SBO after distal gastric bypass may present with vague complaints and confusing laboratory and non-specific findings on x-rays. Delayed diagnosis can have catastrophic consequences. CT imaging with oral and intravenous contrast can be life-saving, and should be obtained in all gastric bypass patients with abdominal pain, particularly when all other parameters seem "normal". Unexplained abdominal pain should prompt exploration.  相似文献   
994.
We report a case of two iatrogenic complications after endovascular repair of a type B aortic dissection treated for abdominal aortic branch ischemia. A rupture of the common iliac artery occurred first during the procedure. A type A dissection occurred 12 days later. The proximal part of the aortic endovascular graft had created a tear in the aortic wall resulting in a retrograde type A dissection. Although aortic endovascular grafting is apparently associated with less morbidity and mortality, potentially lethal complications, both acute and delayed, may arise.  相似文献   
995.
We measured cortical and trabecular bone loss using QCT of the spine and hip in 14 crewmembers making 4- to 6-month flights on the International Space Station. There was no compartment-specific loss of bone in the spine. Cortical bone mineral loss in the hip occurred primarily by endocortical thinning. INTRODUCTION: In an earlier study, areal BMD (aBMD) measurements by DXA showed that cosmonauts making flights of 4- to 12-month duration on the Soviet/Russian MIR spacecraft lost bone at an average rate of 1%/month from the spine and 1.5%/month from the hip. However, because DXA measurements represent the sum of the cortical and trabecular compartments, there is no direct information on how these bone envelopes are affected by spaceflight. MATERIALS AND METHODS: To address this, we performed a study of crewmembers (13 males and 1 female; age range, 40-55 years) on long-duration missions (4-6 months) on the International Space Station (ISS). We used DXA to obtain aBMD of the hip and spine and volumetric QCT (vQCT) to assess integral, cortical, and trabecular volumetric BMD (vBMD) in the hip and spine. In the heel, DXA was used to measure aBMD, and quantitative ultrasound (QUS) was used to measure speed of sound (SOS) and broadband ultrasound attenuation (BUA). RESULTS AND CONCLUSIONS: aBMD was lost at rates of 0.9%/month at the spine (p < 0.001) and 1.4-1.5%/month at the hip (p < 0.001). Spinal integral vBMD was lost at a rate of 0.9%/month (p < 0.001), and trabecular vBMD was lost at 0.7%/month (p < 0.05). In contrast to earlier reports, these changes were generalized across the vertebrae and not focused in the posterior elements. In the hip, integral, cortical, and trabecular vBMD was lost at rates of 1.2-1.5%/month (p < 0.0001), 0.4-0.5%/month (p < 0.01), and 2.2-2.7%/month (p < 0.001), respectively. The cortical bone loss in the hip occurred primarily by cortical thinning. Calcaneal aBMD measurements by DXA showed smaller mean losses (0.4%/month) than hip or spine measurements, with SOS and BUA showing no change. In summary, our results show that ISS crewmembers, on average, experience substantial loss of both trabecular and cortical bone in the hip and somewhat smaller losses in the spine. These results do not support the use of calcaneal aBMD or QUS measurements as surrogate measures to estimate changes in the central skeleton.  相似文献   
996.
Cendan JC  Thomas JB  Seeger JM 《The American surgeon》2004,70(7):583-7; discussion 587
We retrospectively reviewed our experience from 1984 to 2001 with 21 cases of aortoenteric fistula (AEF) in 19 patients. The majority of cases were in men (13 of 19, 68%). One AEF was spontaneous, the other 20 developed after prior vascular reconstruction (95%). The majority of AEF were duodenal (48%) followed by small bowel (38%), colon (10%), and esophageal AEF (5%). The proximal anastomosis of the prior vascular repair was the site of AEF origin in 62 per cent of cases, the distal anastomosis accounted for 19 per cent, and the body of the graft for 14 per cent. The intestinal repair was chosen on a case-by-case basis by the general surgeon and consisted of a simple primary repair in 48 per cent, resection with primary anastomosis in 38 per cent, and patching with pleura or omentum in individual cases. Colostomies were created in the two cases with colonic AEF. The duodenum was excluded in one of 10 duodenal AEF. Six patients (32%) died in the 90 days following surgery. The biggest risk of postoperative death was presentation with sepsis (P = 0.069); interestingly, women were more likely to present with sepsis (P = 0.019) and experienced a disproportionate rate of postoperative death (male 23%, female 50%, P = 0.24). The method used to repair the bowel was linked to a higher rate of postoperative death, and patients that required bowel resection died more frequently (66%) than those who had a simple repair (10%, P = 0.07). Overall mortality with AEF remains high despite routine SICU care. The biggest risk for death is preoperative sepsis. Women presented with sepsis more frequently than men. The method of bowel repair appears to be related to overall survival and along with sepsis is, perhaps, a surrogate for the degree of erosion present at the site of the AEF. Simple bowel repairs were sufficient when technically possible. Duodenal exclusion is not an obligatory adjunct to duodenal repairs.  相似文献   
997.
WP744 is a novel anthracycline with enhanced activity against neuroblastoma   总被引:2,自引:0,他引:2  
BACKGROUND: Coronary artery disease characteristically impacts left ventricular (LV) function on a regional basis, although ultimately global function may be affected as well. Echocardiography is commonly clinically used for the assessment of regional function; however, it is only semiquantitative and in its current iteration is only two-dimensional in nature. Magnetic resonance imaging (MRI) with tissue tagging offers the possibility for noninvasive, three-dimensional (3D) assessment of transmural and segmental left ventricular strain and, thereby, function. Accordingly, we have explored methodologies to accurately and quantitatively characterize regional systolic function in three dimensions in patients with ischemic heart disease using MRI. MATERIALS AND METHODS: MRI radiofrequency tissue tagging was performed at rest and during dobutamine administration (10 mg/kg/min) on 10 normal volunteers (age: 26 +/- 6) and 8 patients with severe ischemic cardiomyopathy (age: 60 +/- 5, EF 26 +/- 11%). Three-dimensional global and regional systolic strain calculations were made based on 3D myocardial point displacements and compared with conventional measures. RESULTS: Global left ventricular strains were significantly decreased in ischemic patients at rest (0.14 +/- 0.04 versus 0.25 +/- 0.02, P < 0.001) and with dobutamine (0.14 +/- 0.03 versus 0.29 +/- 0.03, P < 0.001). In the regional analysis (216 LV wall segments) this methodology accurately differentiated normal from abnormally contracting regions. CONCLUSIONS: Noninvasive dobutamine MRI tissue tagging with calculation of 3D regional strains has significant promise as a clinical tool which is capable of the identification, quantification, and display of regionally varying ventricular function.  相似文献   
998.
OBJECTIVES: To assess the long-term outcome of the efficacy of transurethral resection of the prostate (TURP) in men with detrusor underactivity (DUA), a cause of lower urinary tract symptoms (LUTS) in a significant minority of men. PATIENTS AND METHODS: Neurologically intact men with LUTS, who were investigated in our department between 1972 and 1986, diagnosed with DUA and who underwent surgical intervention, were invited for a repeat symptomatic and urodynamic assessment. Identical methods were used, allowing direct comparison of the results. RESULTS: In all, 224 men were initially diagnosed with DUA; 87 (39%) of these died in the interim and 22 followed had a TURP, with a mean follow-up since surgery of 11.3 years. There were no significantly sustained reductions in any symptoms. There was a small but significant reduction of questionable clinical significance in the bladder outlet obstruction index, but this did not translate into an improved flow rate. Comparison with 58 age-matched patients with DUA who remained untreated showed no significant advantage of surgical intervention in the long-term; on the contrary, there was more chronic retention in those who had had surgery. CONCLUSIONS: There are no long-term symptomatic or urodynamic gains from TURP in men shown to have DUA. The results of TURP in men with DUA are important, as urologists who surgically treat patients based on the symptoms and uroflowmetry alone will do so in a significant minority of men with DUA. These results strengthen the argument for a routine preoperative urodynamic assessment.  相似文献   
999.
Administration of gadolinium chelates at doses greater than 0.1 mmol/kg IV can potentially improve both lesion detection and the assessment of tissue perfusion. Preliminary results are presented in clinical patients and two animal models. In human intracranial metastatic disease, administration of 0.3 (cumulative dose) mmol/kg gadoteridol (Gd HP-DO3A) has permitted detection of additional lesions not visualized at 0.1 mmol/kg. In a rabbit model of focal liver disease, 0.5 mmol/kg IV provided superior enhancement of both normal parenchyma and lesion rim compared to doses of 0.25 and 0.1. Dynamic imaging (T1-weighted turbo-FLASH) immediately following bolus injection of 0.5 mmol/kg permitted direct visualization (on unsubtracted images) of an acute perfusion defect in the cat brain not visible on conventional T1- and T2-weighted scans.  相似文献   
1000.
Outpatient Vascular Intervention: A Two-Year Experience   总被引:3,自引:0,他引:3  
PURPOSE: To retrospectively analyze the outcome of a range of interventional vascular procedures performed on outpatients. METHODS: Suitability for outpatient procedures was assessed according to agreed protocols. An episode was defined as any procedure/s through a single access site at one attendance. Retrospective case-note review was performed. RESULTS: There were 693 outpatient episodes between April 1998 and May 2000 (290 interventional, and 403 diagnostic procedures), comprising 25% (693/2,769) of the total workload. Follow-up is available in 214; 38 of these were transfers from outlying hospitals and were excluded from analysis. One hundred and seventy-six were true outpatients. There were 98 iliac and 46 femoropopliteal interventions, 2 aortic stents, 1 renal and 5 upper-limb angioplasties (PTAs), 5 embolizations, 8 Hickman lines, 1 line stripping, 3 atherectomies, 1 dialysis-graft PTA and 6 bypass-graft PTAs. Sixty-eight closure devices were used. Twelve patients were converted to inpatients (6.8%, 12/176). The readmission rate was 3.4% (6/176). The reattendance rate was 1.1% (2/176), both subsequently attending for outpatient duplex ultrasound examination to exclude pseudoaneurysm. The major complication rate was 3.4% and the delayed major complication rate was 1.7%. CONCLUSION: Outpatient vascular intervention is safe with appropriate protocols and with careful patient selection. Local vascular services benefit from the release of inpatient beds.  相似文献   
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