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11.
Conjunctival squamous cell carcinoma is generally a low-grade malignancy. A 42-year-old man presented with histologic evidence of extra-tumoral perineural invasion associated with an incompletely excised limbal conjunctival squamous cell carcinoma. Despite further surgery, close observation, plaque radiotherapy, and eyelid-sparing orbital exenteration followed by external beam radiotherapy, the patient developed intracranial perineural invasion with involvement of the trigeminal and facial nerves, ultimately resulting in death. Repeated magnetic resonance imaging with contrast failed to detect perineural invasion until late in the course of disease. Awareness of the possibility of perineural invasion in patients with conjunctival squamous cell carcinoma and of its aggressive nature may be life-saving. Nevertheless, even with initial aggressive tumor control, some patients will show an aggressive tumor growth with recurrences.  相似文献   
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PURPOSE: To evaluate ocular parameters that may predispose to the development of branch retinal vein occlusion (BRVO). METHODS: This prospective study included patients with unilateral BRVO evaluated in the authors' clinic. The mean period from the acute phase was 2.29 +/- 1.57 years (range 1-6 years). All patients underwent a complete ophthalmologic examination including subjective refraction, axial length measurements, and keratometry readings. The fellow eye served as a control in each patient. The variables of interest were compared between the affected eye and the fellow eye using the parametric t-test and the nonparametric Wilcoxon test. RESULTS: Twenty-four consecutive patients (14 women, 10 men, mean age 62.4 years) were included in the study. The mean axial length in the affected eye was significantly shorter compared to the mean fellow eye length. No difference was found between the two eyes in mean subjective refraction or mean keratometry readings. CONCLUSIONS: The authors found that eyes with BRVO have a shorter axial length compared to the fellow eye in the same patient.  相似文献   
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We studied the hippocampal angle and spatial relationships of medial temporal lobe (MTL) structures, using midbrain colliculi and inter-collicular sulcus (ICS) as landmarks, and measured MTL width on axial 3D-T1-weighted MRI at ICS level in 41 normal, aged participants. Mean hippocampal angle was 29 degrees (range 17-42 degrees ) caudal to the anterior-posterior commissure (AC-PC) line. The slice at the ICS, parallel to the long axis of the hippocampus, best revealed a longitudinal view of hippocampus and parahippocampal gyrus in 76% of participants, compared to only 7% when slices were 20 degrees caudal to orbitomeatal line (OML), an accepted technique used to examine MTL width in previous CT studies. The MTL width measured midway and at its thinnest between the anterior-posterior borders of the midbrain was highly reproducible (intraclass correlation coefficients >0.98) using these new methods. These simple decision rules, individualized orientation along the hippocampus and using a standardized landmark like the ICS, make these measures more comparable across subjects, and hence more useful in detecting and monitoring MTL atrophy in dementia.  相似文献   
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Congenital ptosis and amblyopia: a retrospective study of 130 cases   总被引:3,自引:0,他引:3  
PURPOSE: To provide supplementary data on the association between congenital ptosis and amblyopia. METHODS: In a retrospective chart study of 130 patients whose congenital ptosis was surgically corrected between 1987 and 1999, 27 (20.8%) had strabismus and 30 (23%) had amblyopia. In 9 patients (6.3%), it was not attributable to any cause except ptosis. RESULTS: There was a high incidence (6.9%) of amblyopia in patients with congenital ptosis. CONCLUSION: We recommend early examination and follow-up of patients with congenital ptosis to diagnose and treat any subsequent amblyopia. Surgery may be indicated should stimulus deprivation amblyopia develop.  相似文献   
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PURPOSE: To investigate a method that uses hyperacuity, the Macular Computerized Psychophysical Test (MCPT), to evaluate the central macular visual field in patients with age-related macular degeneration (AMD). DESIGN: Prospective case-control study of a diagnostic test. PARTICIPANTS AND CONTROLS: One hundred eight eyes of 108 Patients with AMD and 51 eyes of 51 age-matched patients with no retinal disease. Patients with AMD included 32 (30%) patients with choroidal neovascularization (CNV), 23 (21%) with geographic atrophy (GA), 35 (32%) with AMD with high-risk characteristics (HRC), and 18 (17%) with early AMD with non-HRC. TESTING: Each subject underwent the MCPT, in which a virtual line composed of dots (white dots on a black background, maximal contrast) is flashed across different macular loci to a perifoveal radius of 7 degrees. Patients' responses were recorded and automatically analyzed using a specific algorithm developed before the onset of the study. All patients also underwent a supervised Amsler grid examination on the encounter before or after the MCPT in random order. MAIN OUTCOME MEASURES: Distortion, scotoma, or blurring perceived by the patient after a swift change of fixation was considered positive on the MCPT. Any perception of distortion, scotoma, or blurring was considered positive on the Amsler grid. RESULTS: Of the 32 patients with CNV, 30 (94%) were found positive on the MCPT and 11 (34%) were found positive on the Amsler grid. Of the 23 GA patients, 21 (91%) were found positive on the MCPT and 7 (30%) were found positive on the Amsler grid. Of the 35 HRC patients, 28 (80%) were found positive on the MCPT and 3 (9%) were found positive on the Amsler grid, and of the 18 early AMD with non-HRC patients, 8 (44%) were found positive on the MCPT and 3 (17%) were found positive on the Amsler grid. Of the 51 controls, 3 (6%) were positive on the MCPT and 1 (2%) was positive on the Amsler grid. CONCLUSIONS: The MCPT was superior to the Amsler grid in detecting AMD-related lesions in this cohort. Studies are underway to determine whether the MCPT is feasible for home monitoring to provide early detection of progression to CNV.  相似文献   
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The purpose of this study was to generate anatomically guided region-of-interest (ROI) brain SPECT templates based on scans of elderly healthy volunteers. We describe normal tracer uptake and hemispheric asymmetries for each of 3 camera systems and compare these characteristics among systems. METHODS: 99mTc-hexamethyl propyleneamine oxime SPECT scans were acquired from 28 elderly healthy volunteers (mean age [+/-SD], 70.3 +/- 6.5 y) on a single-head rotating gamma camera (n = 15) or on dual- (n = 18) or triple-head (n = 13) cameras. The average number of counts in each ROI was calculated and referenced to counts in a cerebellar ROI, providing semiquantitative regional cerebral blood flow (rCBF) ratios. For the templates and ROI map, base images of a healthy volunteer were obtained with each camera. Data from individuals scanned with 2 cameras on the same day (n = 15) were used to evaluate rCBF differences across cameras. For each camera, averaged SPECT templates were made using automated image registration. The base volunteer's T1-weighted MR image was converted to stereotactic space with dimensions similar to those of the SPECT templates, and 79 bilateral ROIs were defined. To obtain ROI rCBF ratios, we aligned individual images to their appropriate template and then to this modified MR image. RESULTS: The ROI coefficients of variation indicated that the fit of the ROIs was acceptable (0.07-0.35). Mean rCBF ratios ranged from 0.57 to 1.0, 0.67 to 1.01, and 0.63 to 1.00 for single-, dual-, and triple-head cameras, respectively. The cuneus, occipital cortex, occipital pole, middle temporal gyrus, and posterior middle frontal gyrus showed consistent hemispheric asymmetry (right side greater than left side in 83%-100% of individuals). Mean rCBF ratios did not differ between dual- and triple-head cameras, whereas the ratios for single- and dual-head cameras differed significantly (39 ROIs differed), even after smoothing and filtering the dual-head images to the level of the single-head images. CONCLUSION: The use of SPECT templates based on elderly healthy volunteers is an important feature of this technique because most available templates have used young individuals. Another important feature is the use of MR image-based ROIs. These procedures are versatile because they use more than 1 camera. They can easily be implemented in clinical and research settings to detect camera-specific, abnormal deviations in rCBF ROI ratios and asymmetry magnitudes in diseases associated with aging, such as stroke and dementia.  相似文献   
19.
BACKGROUND. In some active multiple sclerosis (MS) lesions, a strong immune reaction at the lesion edge may contain growth and thereby isolate the lesion from the surrounding parenchyma. Our previous studies suggest that this process involves opening of the blood-brain barrier in capillaries at the lesion edge, seen on MRI as centripetal contrast enhancement and a colocalized phase rim. We hypothesized that using these features to characterize early lesion evolution will allow in vivo tracking of tissue degeneration and/or repair, thus improving the evaluation of potential therapies for chronic active lesions.METHODS. Centripetally and centrifugally enhancing lesions were studied in 17 patients with MS using 7-tesla MRI. High-resolution, susceptibility-weighted, T1-weighted (before/after gadolinium), and dynamic contrast–enhanced scans were acquired at baseline and months 1, 3, 6, and 12. For each lesion, time evolution of the phase rim, lesion volume, and T1 hypointensity were assessed. In autopsies of 3 progressive MS cases, the histopathology of the phase rim was determined.RESULTS. In centripetal lesions, a phase rim colocalized with initial contrast enhancement. In 12 of 22, this phase rim persisted after enhancement resolved. Compared with centripetal lesions with transient rim, those with persistent rim had less volume shrinkage and became more T1 hypointense between months 3 and 12. No centrifugal lesions developed phase rims at any time point. Pathologically, persistent rims corresponded to an iron-laden inflammatory myeloid cell population at the edge of chronic demyelinated lesions.CONCLUSION. In early lesion evolution, a persistent phase rim in lesions that shrink least and become more T1 hypointense over time suggests that the rim might mark failure of early lesion repair and/or irreversible tissue damage. In later stages of MS, phase rim lesions continue to smolder, exerting detrimental effects on affected brain tissue.TRIAL REGISTRATION. NCT00001248.FUNDING. The Intramural Research Program of NINDS supported this study.  相似文献   
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Cytokines have been shown to influence susceptibility to febrile seizures and epilepsy. In this study, the role of interleukin-1β (IL-1β) was examined in developing rats. IL-1β and interleukin-1 receptor antagonist (IL-1ra) were administered to developing rats, and seizures were induced by moist warm air. Twenty male Lewis rats (21–23 days old) were divided into two groups (IL-1β and saline control groups) and two holes were made in the skull for EEG electrodes. We applied human recombinant IL-1β intra-nasally 1 h before seizures induced by moist warm air. The brain temperature at the appearance of seizure discharges on EEG, and the latency time from the hyperthermia onset until the appearance of seizure discharges on EEG were measured. And the same study using IL-1ra was performed. The median brain temperature for the IL-1β group, 42.6 °C (range: 41.8–43.0), was significantly lower than that for the control, 42.9 (42.3–43.4) (P = 0.043). The brain temperature for the IL-1ra group, 43.3 (42.8–43.7), was significantly higher than that for the control, 42.9 (42.2–43.5) (P = 0.011), and the latency time for the IL-1ra group, 398 s (270–561), was significantly longer than that for the control, 325 (252–462) (P = 0.035). These results demonstrate that IL-1β promotes hyperthermia-induced seizures in developing rats.  相似文献   
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