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PURPOSE: To evaluate the results of endoscopic sinus surgery (ESS) for paranasal sinus mucocoele with orbital involvement and assess the frequency with which a direct orbital approach is required in these cases. METHODS: Retrospective, consecutive series of sinus mucocoeles with orbital involvement treated by ESS by a single surgeon over a 4-year period (1998-2002). RESULTS: A total of 24 mucocoeles of 15 patients, including 10 frontal, eight frontoethomoidal, two ethmoidal, and four maxillary. All cases demonstrated radiological orbital extension. Globe displacement was seen in 73%. At a median follow-up of 15.5 months, the mean cumulative clinical score improved from 4.2 +/- 1.5 (range 1-7) to 0.4+/-0.7 (range 0-2). Ophthalmic symptoms and signs resolved in all patients but one who had complex sinus anatomy following neurosurgery. Minor, self-limiting complications including epistaxis and intranasal adhesions occurred in three cases. Additional endoscopic sinus surgery was required in four patients for revision of narrowed frontal sinus ostium (two), mucocoele recurrence (two), and sinus toileting (one). No cases required external sinus surgery and the average hospital in-patient stay was 2.5 +/- 1.6 days. At final follow-up, sinus ostia were patent in all excluding one case that required a stent due to disrupted anatomy. CONCLUSION: ESS is effective in improving ophthalmic symptoms and signs due to paranasal sinus mucocoele. ESS may be a viable treatment for paranasal sinus mucocoele with orbital extension, and a direct orbital approach is rarely necessary. 相似文献
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Khong PL Tse C Wong IY Lam BC Cheung PT Goh WH Kwong NS Ooi GC 《Journal of child neurology》2004,19(11):872-881
We evaluated early diffusion-weighted imaging findings, the quantitative apparent diffusion coefficient, and magnetic resonance spectroscopy (the presence of lactate and ratios of N-acetylaspartate to total creatine and choline to total creatine) in the prediction of the 18-month neuromotor outcome of term newborns with hypoxic-ischemic encephalopathy. Conventional T1- and T2-weighted and diffusion-weighted imaging was performed in 20 asphyxiated term newborns, with additional basal ganglia magnetic resonance spectroscopy in 15 newborns between 2 and 18 days of life (mean 7.3 days). Neuromotor outcome was dichotomized into normal and abnormal for statistical analysis. Statistically significant differences in the ratios of N-acetylaspartate to total creatine, but not apparent diffusion coefficient values and ratios of choline to total creatine, were found between infants with a normal and an abnormal outcome (Mann-Whitney U-test, P = .010). There was a significant association between the presence of a lactate peak and an abnormal outcome (chi-square test, P = .017). The presence of a lactate peak for predicting an abnormal outcome had a sensitivity of 100% and a specificity of 80%, and the odds ratio was 37.4. Ischemic lesions were more conspicuous and/or extensive on diffusion-weighted imaging in all except one neonate. The presence of normal findings on both diffusion-weighted imaging and conventional magnetic resonance imaging is predictive of a normal neuromotor outcome, whereas lactate and a reduced ratio of N-acetylaspartate to total creatine in the basal ganglia, but not an apparent diffusion coefficient, are associated with an abnormal outcome at 18 months of age. 相似文献
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Childhood acute disseminated encephalomyelitis: the role of brain and spinal cord MRI 总被引:3,自引:0,他引:3
BACKGROUND: It is recognised that the clinical and radiological spectrum of childhood acute disseminated encephalomyelitis (ADEM) is wide. OBJECTIVE: To determine whether initial MRI features are predictive of clinical outcome and to determine the role of MRI in the management of ADEM. MATERIALS AND METHODS: The MRI scans of ten consecutive children (eight boys, two girls), clinically and radiologically diagnosed to have ADEM, were retrospectively reviewed. Follow-up MRI was available for eight patients. RESULTS: Lesions ranged from small and punctate (<1 cm) to moderate sized and confluent (4-5 cm) to diffuse and extensive. Spinal cord lesions, seen in five of seven children, were contiguous or segmental. Seven children (70%) made good clinical recovery while three children (30%) remained severely handicapped. There was no correlation between the site, extent and pattern of involvement and clinical outcome. However, the evolution of MRI findings on follow-up correlated well with the subsequent clinical course and outcome. CONCLUSIONS: Although the extent and site of lesions on initial MRI scans are not predictive of clinical outcome, early MRI of the brain and spine is useful in aiding clinical diagnosis, and subsequent follow-up MRI is helpful in monitoring disease progression. 相似文献
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Unmodified prolactin (PRL) promotes PRL secretion and acidophil hypertrophy and is associated with pituitary hyperplasia in female rats 总被引:1,自引:0,他引:1
In this study, we have tested the hypothesis that unmodified prolactin (U-PRL) and phosphorylated prolactin (P-PRL) have differential
roles in the autoregulation of PRL secretion in vivo. Recombinant human U-PRL and a molecular mimic of P-PRL (S179D PRL) were
administered to male rats and to female rats in different physiological states and the effect on rat PRL release was measured.
Administration of U-PRL elevated rat PRL in all female animals, but was without effect in males. By contrast, S179D PRL was
inactive in females, but inhibited PRL release in males. Morphometric and immunohistochemical analyses demonstrated acidophil
hypertrophy and evidence of increased PRL secretion in the pituitaries of U-PRL-treated females. Analysis of the two forms
of PRL during prolactinoma induction in two differentially susceptible strains of rats found a strong temporal correlation
among increased ratios of U-PRL: P-PRL, increased circulating PRL, and increased cell proliferation. We conclude (1) that
the autoregulatory mechanism(s) can distinguish between the two major forms of PRL and that higher proportions of U-PRL not
only allow for higher circulating levels of PRL, but are also autostimulatory, (2) that the autoregulatory mechanism(s) are
set differently in males and females such that females are more sensitive to autostimulation by U-PRL and less sensitive to
inhibition by P-PRL, and (3) that U-PRL and P-PRL may also have differential roles in the regulation of pituitary cell proliferation. 相似文献
50.
PURPOSE: To describe and quantify thin-section computed tomographic (CT) features of the lung in patients with beta-thalassemia major (beta-TM) and determine the correlation between thin-section CT findings, pulmonary function test (PFT) results, and iron overload. MATERIALS AND METHODS: Forty-one patients with beta-TM (mean age, 24.5 years) underwent thin-section CT (during full inspiration and expiration) and PFTs. Two radiologists in consensus recorded the presence of focal bronchial and parenchymal abnormalities and air trapping. A semiquantitative air trapping score (ATS) was used, and patients were separated into air trapping-negative (ATS between 0 and 3) and air trapping-positive (ATS > 3) groups for statistical analysis. Iron overload was estimated by calculating the ratio of the signal intensity (SI) of the liver to the SI of paraspinous muscle by using magnetic resonance imaging in 27 patients (66%). We performed multiple logistic regression analysis to study the influence of age, PFT findings, and SI ratio on the presence of air trapping at CT and multivariate regression analysis to study the simultaneous influence of the presence of air trapping on obstructive PFT indexes. RESULTS: Air trapping was the predominant thin-section CT finding and was seen in 10 (24%) of 41 patients. No patient had interstitial lung disease at CT, although 11 (27%) had a restrictive spirometric pattern. Simple logistic regression analysis revealed significant associations between ATS and forced expiratory volume in the first second (FEV1), FEV1/forced vital capacity (FVC), forced expiratory flow (FEF) in the midexpiratory phase (FEF25%-75%), FEF at 50% of the FVC (FEF50%), and FEF at 75% of the FVC (FEF75%) (P =.019,.030,.007,.034, and.021, respectively) but not between ATS and SI ratio. At multiple logistic regression analysis, only FEF25%-75% was significantly associated with ATS (P =.019, adjusted odds ratio = 0.86, R2 = 41.8%). Multivariate analysis revealed that ATS did not have a significant influence on lung function indexes (P =.104), although significant effects were found with FEV1, FEF25%-75%, FEF50%, and FEF75% when examined separately. CONCLUSION: Air trapping may be present at expiratory thin-section CT in patients with beta-TM and is associated with reduced FEF25%-75% values but not hepatic iron overload. 相似文献