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排序方式: 共有438条查询结果,搜索用时 15 毫秒
21.
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   
22.
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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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   
25.
Johnson TE  Vue M  Brekhus S  Khong A  Ho TW  Walker AM 《Endocrine》2003,20(1-2):101-109
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   
26.
Khong PL  Chan GC  Lee SL  Au WY  Fong DY  Tsang KW  Ooi GC 《Radiology》2003,229(2):507-512
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   
27.
BACKGROUND AND PURPOSE: Treatment-induced white matter (WM) injury in medulloblastoma survivors, as manifested by deterioration of cognitive function, is prevalent. However, no reliable imaging method exists for early detection and quantification. Our goal was to determine whether anisotropy of WM is reduced in medulloblastoma survivors and whether fractional anisotropy (FA) can be used as an index for evaluation of treatment-induced WM injury. METHODS: We evaluated nine medulloblastoma survivors treated with surgery, cranial irradiation, and chemotherapy by use of diffusion-tensor (DT) imaging and compared FA findings in selected WM sites (cerebellar hemispheres, pons, medulla oblongata, frontal periventricular WM, parietal periventricular WM, and corona radiata) with those of healthy age-matched control subjects. FA maps were compared with conventional T2-weighted images. FA was also compared with age at treatment, time interval since treatment, and deterioration of school performance. The two-tailed paired t test was used to determine statistical significance (P <.05). RESULTS: Significant reduction of FA (P <.05) was seen in all anatomic sites in the patient group compared with FA in control subjects, except in the frontal periventricular WM, even in areas with normal appearance on T2-weighted images. FA reduction ranged from 12.4-19% (mean, 16.5%). Compared with control subjects, posterior fossa and supratentorial WM FA in patients were reduced by 14.6% (SD 1.9%) and 18.4% (SD 0.55%), respectively (P =.029). Reduction of supratentorial WM FA correlated with younger age at treatment (< 5 years), longer interval since treatment (> 5 years), and deterioration of school performance. CONCLUSION: DT imaging and use of the index FA is potentially useful for early detection and monitoring of treatment-induced WM injury in children with medulloblastoma.  相似文献   
28.
Ooi CG  Khong PL  Ho JC  Lam B  Wong WM  Yiu WC  Wong PC  Wong CF  Lai KN  Tsang KW 《Radiology》2003,229(2):500-506
PURPOSE: To evaluate the relationship among chest radiographs, oxygen supplementation requirement, and treatment response in severe acute respiratory syndrome (SARS). MATERIALS AND METHODS: Forty patients (20 women, 20 men; mean age, 42.90 years +/- 14.01 [SD]; median age, 41.5 years; age range, 25-82 years) with SARS were evaluated. Daily chest radiographs were graded according to percentage of lung involvement during 20.15 days +/- 5.56 (median, 20 days; range, 14-38 days). Times between symptoms and treatment and time to reach maximal radiographic score from admission and treatment day were determined. Daily oxygen saturation (Sao2) and oxygen supplementation including mechanically assisted ventilation were recorded. Treatment response was defined as good, fair, and poor. Patterns of radiographic opacity at admission and at maximal radiographic score were noted. Differences in radiographic and clinical parameters with respect to oxygen supplementation and treatment response were respectively evaluated with Mann-Whitney and Kruskal-Wallis tests. RESULTS: Larger maximal radiographic scores, lower Sao2 at maximal radiographic change, longer time from treatment to maximal radiographic score (P <.01), and diffuse consolidation at maximal radiographic score were associated with oxygen supplementation. Parameters that influenced treatment response were time from symptom onset to treatment day (P =.003), time from admission to treatment day (P <.001), time to maximal radiographic score from treatment day (P =.001), maximal radiographic score (P =.009), Sao2 at maximal radiographic score (P =.13), and treatment radiographic score (P =.03). Fair responders had shorter time between admission and treatment than did either good (P <.001) or poor responders (P =.002) and shorter time between symptoms and treatment (P <.001) and lower treatment radiographic score (P =.012) than did good responders. Good (82%), poor (36%), and fair (33%) responders developed maximal chest radiographic scores within 4 days of treatment (P =.008). Radiographic patterns at both admission and maximal radiographic score did not influence treatment response. CONCLUSION: There are significant relationships among radiographic parameters, oxygen supplementation, and treatment response, and these relationships appear to be clinically useful in the treatment of SARS.  相似文献   
29.
Solid-cystic papillary tumor of the pancreas in children   总被引:4,自引:0,他引:4  
Solid-cystic papillary tumor (SCPT) of the pancreas is a rare neoplasm in children. The current study attempted to estimate the incidence and possible pathological origin of the tumor. Clinicopathologic features of the children under the age of 16 years with pancreatic tumors managed in a single institution between January 1993 and November 1999 were reviewed. Representative blocks of SCPT specimens were immunostained for neuron-specific enolase (NSE) chromogrannin, synaptophysin, insulin, glucagon, somatostatin, and gastrin. There were three SCPTs, two pancreatic endocrine tumors, and one acinar cell carcinoma during the study period. The estimated yearly incidence in the referral area of 2 million population is about 0.01 pediatric SCPT per year per 100,000 population. The children underwent surgical removal of the tumors. Postoperatively, they were followed up for 6 months to 4 years and were well. Immunostaining for NSE, chromogranin, synaptophysin, insulin, somatostatin, and gastrin was negative in all cases. SCPT may thus be the most common pancreatic tumor in the Asian pediatric population. The pathological origin of the tumor remains unclear and requires further investigations. Accepted: 30 October 2000  相似文献   
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