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991.
Neurocysticercosis (NCC) has a worldwide distribution mainly in the developing countries like India. The study was done to find the seroprevalence of anti-cysticercus antibodies in clinically suspected and MRI proven cases and to corroborate the serological findings with radiological findings (MRI). A hospital based study among 204 suspected patients during January, 1996 to August, 2001 showed that 77 (32.2%, M:F = 2.2:1) had serological evidence of NCC. Of the total 189 sera, tested at 1:100 dilution 68 (35.9%) and of the total 50 CSF, tested at 1:5 dilution 9 (18%) were positive for anti-cysticercus IgG antibodies. In 35 cases where both were tested 13 sera (37.1%), 9 CSF (25.7%) and in 7 (20%) both sera and CSF were positive. In CSF from 62 patients with tubercular meningitis (disease control) 2 (3.2%) samples whereas in sera of 60 normal blood donors (normal control) 7 (11.7%) samples had anti-cysticercus IgG antibodies. In 33 MRI-positive cases, anti-cysticercus antibodies were seen in 15 (45.4%) patients. Antibodies were seen in 6 of 14 (42.8%) cases with single cortical cyst, 4 of 11 (36.3%) with 2-3 cysts and in 5 of 8 (62.5%) with multiple cysts. Alternatively, 18 of 33 (54.5%) MRI positive cases lacked anti-cysticercus antibodies. Six MRI negative cases were found to be seropositive and were treated successfully. Hence, immune response was sub-optimal even in MRI positive cases and conversely, few MRI negative cases were seropositive. Since positive response with MRI or serology depends on the stage of the disease, therefore both tests should be done together to confirm or to rule out NCC.  相似文献   
992.
Evidence-based risk factors for postoperative deep vein thrombosis   总被引:3,自引:0,他引:3  
BACKGROUND: Deep vein thrombosis (DVT) is a common postoperative complication that is associated with significant morbidity and mortality. Thromboprophylaxis has been shown to be underused. In the absence of prophylaxis, rates as high as 50% have been reported following orthopaedic surgery, and 25% following general surgery. Many risk factors have been suggested but there is often little evidence to support these claims. METHODS: A systematic review was performed to determine the evidence base behind each suggested risk factor, and, where sufficient data were available, a random-effects meta-analysis was performed. RESULTS: There is evidence to support a significant association between increased age, obesity, a past history of thromboembolism, varicose veins, the oral contraceptive pill, malignancy, Factor V Leiden gene mutation, general anaesthesia and orthopaedic surgery, with higher rates of postoperative DVT, although there remain some variables within the study designs that may lead to overestimation of effect. There is no evidence to support the suggested risk factors of hormone replacement therapy, gender, ethnicity or race, chemotherapy, other thrombophilias, cardiovascular factors, smoking and blood type. CONCLUSIONS: An accurate knowledge of evidence-based risk factors is important in predicting and preventing postoperative DVT, and can be incorporated into a decision support system for appropriate thromboprophylaxis use.  相似文献   
993.
AIM: To evaluate the regional cerebral blood flow (rCBF) changes following IV mannitol bolus in patients with intracerebral hemorrhage (ICH). METHODS: In a hospital based randomized placebo controlled study, 21 CT proven ICH patients with Glasgow coma scale (GCS) score of 5 or more were subjected to clinical evaluation including GCS and Canadian Neurological stroke (CNS) scale. Cranial SPECT study was undertaken before and 60 min after 20% mannitol 100 ml IV in 20 min or sham infusion. The SPECT images were semi-quantitatively analyzed and asymmetry index of basal ganglia, frontal, parietal and occipital regions were calculated. RESULTS: There were 12 patients in mannitol and nine in control group who were evenly matched for age, mean arterial blood pressure, GCS score and size of hematoma. Only one patient died in mannitol group. Following mannitol, GCS score improved in six, worsened in two and remained unaltered in four patients. In the control group, GCS improved in seven, worsened in none and was unchanged in two patients. SPECT studies revealed reduction in asymmetry index in basal ganglia in four, frontal region in six, parietal in four and occipital region in five patients in mannitol group. In control group, asymmetry index was reduced in basal ganglia in one, frontal and parietal region in three each and occipital region in five patients. These differences between control and study group were not significant. CONCLUSION: Mannitol does not seem to significantly change the regional cerebral blood flow (rCBF) in ICH patients as evaluated by SPECT study.  相似文献   
994.
BACKGROUND: In 1999, a statement of best practice in primary total hip replacement was approved by the Council of the British Orthopaedic Association (BOA) and by the British Hip Society (BHS) to provide a basis for regional and national auditable standards. We have compared practice in the North West Region of England to this document to ascertain adherence to this guide to best practice. METHODS: A total of 86 surgeons from 26 hospitals were included in a questionnaire study. RESULTS: A mean of 93.3% of operations were performed in the surgeon's usual theatre. All of these theatres had vertical laminar air flow systems. Of respondents, 42.2% routinely used exhaust suits, 68.1% routinely used impermeable disposable gowns, and 26.1% used impermeable re-usable gowns. The Charnley femoral and acetabular prostheses were the most commonly used prostheses. All surgeons used some form of anti-thromboembolic prophylaxis: 66.2% use a combination of both mechanical and chemical means. All surgeons used antibiotic prophylaxis. The most popular choice of antibiotic was a cephalosporin--70.7% used a 3-dose regimen over 24 h, 2.6% of surgeons continued antibiotic prophylaxis for 48 h after surgery, and 93.7% of surgeons routinely use antibiotic-loaded cement. All surgeons routinely cleaned, irrigated and dried the acetabulum and femur before cement insertion. Only one surgeon did not use any form of femoral canal occlusion. 69.4% used an intramedullary bone block. Retrograde filling of the femoral shaft by means of a cement gun was practised by 65.1%. CONCLUSIONS: This study has demonstrated considerable variation of practice in total hip arthroplasty across the North West Region and significant divergence from the statement of best practice approved by the BOA and BHS. The introduction of a properly funded national hip register will surely help to clarify the effect of such diverse practice on patient outcome. We would recommend that all trusts locally audit their practices and correlate them with these nationally agreed guidelines.  相似文献   
995.
Summary Background. This prospective study, conducted in patients with Chiari I malformation (C I) related syringomyelia who underwent posterior decompression and duroplasty, utilizes radionuclide cisternography in order to study the cerebrospinal fluid (CSF) dynamics at the foramen magnum and to predict the clinical outcome following surgery.Methods. 17 consecutive patients of C I with syringomyelia (but without hydrocephalus or fixed atlanto-axial dislocation), underwent a detailed neurological examination and were assigned a clinical disability score based on the modified Klekamp and Samii score. A radionuclide cisternography (using Tc99m-DTPA) was performed via the lumbar route and the ascent of the tracer was followed utilizing a gamma camera immediately after injection and then sequentially after 1, 2, 4, 6 and 24 hours. After posterior decompression and duroplasty, the modified Klekamp and Samii score was repeated at follow-up visits (range: 3 months to one year) along with radionuclide cisternography at 3 months, and MR imaging at 6 months.Findings. Three patterns of tracer flow were observed: a) rapid flow (n=7); b) supratentorial subarachnoid delay (n=7); and, c) foramen magnum block (n=3). The patients having foramen magnum block had the poorest clinical scores on admission. At follow up, there was an improvement in the clinical scores so that the mean scores in all three categories reached nearly the same level. Following posterior decompression, the radionuclide cisternography performed in 10 patients showed a rapid flow of the tracer without any obstruction. The syrinx resolved in 4 of the 11 patients in whom an MRI was done.Interpretation. The patients with C I with syringomyelia may often have a free flow of tracer across the FM. Posterior decompression and duroplasty provides maximum clinical relief in patients with a demonstrable foramen magnum block on radionuclide cisternography while those with a normal flow have less relief. The symptomatology related to brain-stem compression immediately responds to the surgical procedure but the syrinx-induced signs and symptoms of spinal cord dysfunction persist.  相似文献   
996.
There are clinical, laboratory and imaging criteria to distinguish multiple sclerosis (MS) from neuromyelitis optica (NMO) and acute disseminated encephalomyelitis (ADEM). While MS has unknown aetiology, NMO is commonly associated with vasculitis and ADEM is supposed to be parainfectious in origin. In the present study, six patients are described from a group of 67 with a central demyelinating disorder whose clinical presentation did not conform to existing diagnostic criteria for ADEM, NMO or MS. Their clinical, laboratory and imaging characteristics were studied and analysed. Some features suggested a particular diagnosis but some other features favoured another diagnosis. The features included spinal cord involvement in a large vertical segment with cord swelling, optic neuritis, no lesions in the cerebral cortex, paraplegia with urinary retention during the acute phase, no oligoclonal band in cerebrospinal fluid, absence of any evidence of vasculitis, wide time-gap between spinal cord and optic nerve involvement, good recovery from acute phase of disease and a relatively benign course. We conclude that there exists a subpopulation of patients with central demyelinating disease in this region with mixed clinical features. Overall features suggested either a widened clinical spectrum of MS, NMO or ADEM or a possible overlap between them.  相似文献   
997.
998.
BACKGROUND: A single umbilical artery (SUA) in a fetus may be associated with hydronephrosis. CASES: We describe 2 cases of SUA, one of which had severe hydronephrosis with ascites and was stillborn. The other case was born alive with a unilateral hydroureter and is being managed with close monitoring. CONCLUSION: Detection of SUA on antenatal ultrasound should prompt a careful search for urinary tract abnormalities, as associated severe hydronephrosis may lead to a poor outcome.  相似文献   
999.
1000.
We studied the effect of perilesional gliosis on seizure recurrence after stopping antiepileptic drug (AED) therapy in 108 patients with a solitary cysticercal brain cyst. All patients received albendazole therapy in the beginning, and magnetic resonance imaging (MRI) done after 2 seizure-free years showed complete disappearance of the lesion in 67, partial degeneration in 12, and healing by calcification in 29. The gliosis, which was not visible on initial MRI, was observed near the lesion in 22 (20%) patients on T1-weighted magnetization transfer spin-echo (MTSE) MRI. Initial seizure control was difficult with single AED therapy in 16 of 22 patients with gliosis but only in 8 of 86 patients without gliosis. On stopping AED therapy, patients with perilesional gliosis had a higher incidence of seizure recurrence (19 of 22 patients) compared with those who did not demonstrate gliosis (9 of 86 patients). The presumption that gliosis visible on MTSE MRI correlates with seizure recurrence had a high specificity (96%) but only moderate sensitivity (68%). Our findings suggest that there is a group of patients with neurocysticercosis in whom the risk of seizure recurrence is actually high. Several such patients have perilesional gliosis that can be identified on T1-weighted MTSE MRI. These patients probably need long-term AED administration.  相似文献   
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