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41.
SL Stuckey EJ Gilford PJ Smith M Kean 《Journal of Medical Imaging and Radiation Oncology》1995,39(4):350-355
This preliminary study was designed to investigate the ability of multiple axial volume three-dimensional fourier transform (3DFT) time-of-flight (TOF) magnetic resonance angiography (MRA) to depict the carotid bifurcation in the early post-carotid endarterectomy period. Five patients underwent intra-operative digital subtraction angiography (DSA) and carotid MRA within 5 days of carotid endarterectomy. An axial volume fast imaging in steady-state precession (FISP) gradient-echo 3DFT TOF carotid MRA technique in this limited series appeared to display accurately the surgically significant abnormalities at the carotid bifurcation after endarterectomy. However, in normal or near-normal intra-operative DSA studies, overestimation of internal carotid artery stenoses was encountered. Postoperative MRA demonstrates potential as a useful non-invasive investigation after carotid endarterectomy but should be interpreted with caution until larger studies become available. 相似文献
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Ma SL Shea JA Galetta SL Jacobs DA Markowitz CE Maguire MG Balcer LJ 《American journal of ophthalmology》2002,133(5):686-692
PURPOSE: To examine vision-specific health-related quality of life in a cohort of patients with multiple sclerosis (MS) using the 25-Item National Eye Institute Visual Function Questionnaire (VFQ-25), and to identify content areas for a brief MS-specific vision questionnaire. DESIGN: Cross-sectional survey. METHODS: The VFQ-25 and a modified version of the Optic Neuritis Treatment Trial (ONTT) Patient Questionnaire were administered by in-person interview to 80 patients at the University of Pennsylvania MS Center. Binocular visual acuities were obtained following a standard protocol using retroilluminated Early Treatment Diabetic Retinopathy Study charts. RESULTS: Despite a median binocular visual acuity of 20/16 (20/12.5-20/250), VFQ-25 subscale scores in the MS cohort were significantly lower (worse) compared with those of a published reference group of eye disease-free patients (P =.0001-0.009, two-tailed t tests). Rank-correlations of VFQ-25 composite (overall) scores with visual acuity were modest, but significant (r(s) = 0.33, P =.003), supporting construct validity for VFQ-25 scores in MS populations. Seven additional aspects of self-reported visual dysfunction in MS were also identified. CONCLUSIONS: Patients with MS have a high degree of self-reported visual dysfunction that is not entirely captured by visual acuity. The VFQ-25 is an effective measure of self-reported visual loss in MS. A brief MS-specific vision questionnaire may provide additional useful information when administered concurrently with the VFQ-25 in future investigations of MS and other neuroophthalmologic disorders. 相似文献
44.
Orbital pseudotumor, also known as idiopathic orbital inflammatory syndrome (IOIS), may have protean clinical manifestations. Some presentations of IOIS may mimic common conditions such as orbital cellulitis and optic neuritis. IOIS should be considered a diagnosis of exclusion, with evaluation directed toward eliminating other causes of orbital disease. Orbital magnetic resonance imaging is the single most important diagnostic test, but serologic studies are necessary to exclude a systemic cause. Biopsy is usually not performed at presentation, as the risk of producing damage to vital structures within the orbit outweighs the benefits. Patients with multiple recurrences, or those unresponsive to therapy, should have biopsy samples taken. Corticosteroids are the mainstay of therapy and are administered for several months to ensure remission. Radiotherapy may be used in patients who fail to respond to steroids or who have a rapidly progressive course. For those patients who are refractory to both corticosteroids and radiotherapy, anecdotal reports have suggested the use of chemotherapeutic agents such as cyclophosphamide, methotrexate, and cyclosporine. 相似文献
45.
Patients with typical acute monosymptomatic demyelinating optic neuritis should receive gadolinium-enhanced magnetic resonance imaging (MRI) of the brain and orbits to determine if they are at high risk for the subsequent development of clinically definite multiple sclerosis (CDMS). The presence of >or=2 white matter lesions (>or=3 mm in diameter, at least 1 lesion periventricular or ovoid) indicates high risk for CDMS; the following treatment should be considered for such patients: 1. Intravenous methylprednisolone sodium succinate (1 gram IV/day for 3 days) followed by oral prednisone (1 mg/kg/day for 11 days) with 4-day taper (20 mg on day 1, 10 mg on days 2 and 4); 2. Interferon beta 1-a (Avonex 30microg intramuscularly [IM] weekly, or Rebif 22 microg subcutaneously [SQ] weekly). These two drugs have been shown to reduce the short-term risk of CDMS in high risk monosymptomatic patients. In monosymptomatic patients with <2 white matter lesions, and in patients for whom CDMS has been established, IV methylprednisolone treatment followed by oral prednisone should be considered on an individual basis. Treatment in these patients may hasten visual recovery, but does not affect long-term visual outcome. Oral prednisone alone, without prior treatment with IV methylprednisolone, may increase the risk for recurrent optic neuritis and should be avoided. 相似文献
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47.
Transcervical thymectomy for myasthenia gravis achieves results comparable to thymectomy by sternotomy 总被引:3,自引:0,他引:3
Shrager JB Deeb ME Mick R Brinster CJ Childers HE Marshall MB Kucharczuk JC Galetta SL Bird SJ Kaiser LR 《The Annals of thoracic surgery》2002,74(2):320-6; discussion 326-7
BACKGROUND: It remains controversial whether transcervical thymectomy offers results equivalent to thymectomy by way of a median sternotomy in the treatment of myasthenia gravis. Furthermore, preoperative prognostic factors have not been clearly defined. METHODS: This study is a retrospective chart review and interview of 78 patients completing transcervical thymectomy for myasthenia gravis between 1992 and 1999. RESULTS: There were 24 men and 54 women. Mean age was 40 years (range, 13 to 78 years). Twelve patients were in Osserman class 1, 25 in class 2, 30 in class 3, and 11 in class 4 (mean, 2.5). There was no perioperative mortality and 6 (7.7%) morbidities. Mean length of stay was 1.5 days and mean follow-up, 54.6 months. The crude cumulative complete remission (asymptomatic off medications for 6 months) rate was 39.7% (n = 31). Only 8 patients (10.3%) failed to improve after transcervical thymectomy. Kaplan-Meier estimates of complete remission were 31% and 43% at 2 and 5 years, respectively. Eight patients with thymoma had a 5-year estimated complete remission rate of 75% in contrast to 43% in 38 patients with thymic hyperplasia and 36% in 32 patients with neither thymoma nor hyperplasia (p = 0.01). Twelve patients with ocular myasthenia had a 5-year estimated complete remission rate of 57%, whereas patients with mild-to-moderate (n = 55) or severe (n = 11) generalized symptoms had 5-year complete remission rates of 43% and 30%, respectively (p = 0.21). CONCLUSIONS: Overall, extended transcervical thymectomy offers results that are comparable to those published for the transsternal procedure. Patients with milder disease (including isolated ocular disease) and taking no preoperative immunosuppressive agents appear to experience higher remission rates. In contrast to previous studies, we also find that small thymomas predict better responses to thymectomy. 相似文献
48.
A patient presented with symptoms of limbic and brainstem encephalitis, motor and sensory neuronopathy, cerebellar dysfunction, and highly positive anti-Hu antibodies. He also harbored P/Q-type calcium channel antibodies and manifested the Lambert-Eaton myasthenic syndrome (LEMS). Small-cell lung cancer was found, and he received both antineoplastic therapy and intravenous immunoglobulin (IVIg). Remission of the malignancy was achieved. Although the anti-Hu-related manifestations improved after therapy, LEMS has persisted, leading to IVIg dependency. 相似文献
49.
Kaiser JS Grossman RI Polansky M Udupa JK Miki Y Galetta SL 《AJNR. American journal of neuroradiology》2000,21(6):1043-1047
BACKGROUND AND PURPOSE: Patients presenting with a monosymptomatic episode of neurologic dysfunction (MEND) have a high probability of developing multiple sclerosis (MS). Our study was designed to determine whether magnetization transfer (MT) histogram analysis could predict the development of MS for a cohort of patients presenting with a MEND. METHODS: Eleven patients with a MEND and 21 age-matched control volunteers underwent MR imaging. Six patients underwent serial MR examinations. MT ratio histogram peak height (MTRHPH) and the location of the MT ratio histogram peak (LOC MTRHP) were determined for patients and control volunteers. T2 lesion volume was also calculated. Patients were clinically followed up for 587 +/- 308 days to determine or rule out the development of MS. RESULTS: Three patients went on to develop MS. There was no statistically significant difference in the MTRHPH (P = .65) and the LOC MTRHP (P = .71) between patients and control volunteers. For those patients who underwent multiple examinations, no statistically significant differences in the MTRHPH (P = .64), LOC MTRHP (P =.58), and T2 lesion volume (P = .47) were seen. There were no statistically significant correlations between any of the parameters studied. CONCLUSION: We found no difference in MT histogram parameters among control volunteers, patients with a MEND without MS, and patients with a MEND who went on to a diagnosis of MS. Our preliminary findings suggest that there may not be a substrate of disease in the normal-appearing white matter that is predictive of the development of MS. 相似文献
50.