ABSTRACT
Two patients with progressive aphasia without dementia had magnetic resonance imaging findings of focal left temporal lobe abnormality. Unlike most of the other documented cases of progressive aphasia, onset was not presenile, occurring at ages 68 and 69.
Subject(s)
Aphasia/diagnosis , Aged , Aphasia/complications , Dementia/complications , Humans , Magnetic Resonance Imaging , Male , Temporal Lobe/pathologyABSTRACT
Fourteen patients with CNS manifestations of neurosarcoidosis were evaluated by MR imaging and CT. Evaluations were done on a 0.5-T superconductive magnet with T1- and T2-weighted sequences. CT with contrast was obtained in all patients. The granulomatous lesions were classified by location into basilar, convexity, intrahemispheric, and periventricular white-matter involvement. Hydrocephalus with or without an associated lesion was also noted. MR determined the presence of disease in all patients (100%), but was less accurate than CT in depicting disease in two patients (14%). CT determined the presence of disease in 12 patients (85%) and was less accurate than MR in delineating hypothalamic involvement in two patients and periventricular white-matter disease in three patients. There was great variability in the appearance of intracranial sarcoidosis on MR. Three patients had lesions that were isointense or hypointense (relative to cerebral cortex) on both T1- and T2-weighted images while nine patients had lesions that were hyperintense on T2-weighted images. Convexity involvement and hydrocephalus were well documented by both CT and MR. These results indicate that both MR and CT are helpful in fully evaluating a patient with suspected intracranial sarcoidosis.
Subject(s)
Brain Diseases/diagnosis , Magnetic Resonance Imaging , Sarcoidosis/diagnosis , Tomography, X-Ray Computed , Adult , Brain/diagnostic imaging , Brain/pathology , Brain Diseases/diagnostic imaging , Female , Humans , Hydrocephalus/diagnosis , Hydrocephalus/diagnostic imaging , Hydrocephalus/etiology , Male , Sarcoidosis/complications , Sarcoidosis/diagnostic imagingABSTRACT
The behavior of the vestibulo-ocular reflex (VOR) during both passive and active, high-velocity head movements was recorded in three normal subjects. We found that the VOR is compensatory for head velocities up to at least 350 deg . s-1, during both active and passive head rotation provided there is an attempt to visualize a real (or imagined) stationary object in space. Slow phase velocities, however, could reach values as high as 500 deg . s-1. Furthermore, during passive rotation at high velocities, the quick phase trajectory is modified--indicating an interaction between the slow phase and quick phase eye velocity commands.