Robert A. Zimmerman

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The type, frequency, and extent of MR signal abnormalities in Alzheimer's disease and normal aging are a subject of controversy. With a 1.5-MR unit we studied 12 Alzheimer patients, four subjects suffering from multiinfarct dementia and nine age-matched controls. Punctate or early confluent high-signal abnormalities in the deep white matter, noted in 60% of(More)
A prospective sample of 69 healthy adults, age range 18-80 years, was studied with magnetic resonance imaging scans (T2 weighted, 5 mm thick) of the entire cranium. Volumes were obtained by a segmentation algorithm that uses proton density and T2 pixel values to correct field inhomogeneities ("shading"). Average (+/- SD) brain volume, excluding cerebellum,(More)
OBJECTIVE Brain magnetic resonance imaging (MRI) and neuropsychological evaluations were conducted to determine whether neuroradiographic evidence of infarct in children with sickle cell disease between ages 6 and 12 years would result in impairment in cognitive and academic functioning. METHOD AND DESIGN Children enrolled in the Cooperative Study of(More)
The presentation, growth patterns, and response to therapy of 11 consecutive children with choroid plexus carcinomas were analyzed, and the results were compared with the outcome reported in other series. Patients were a median of 26 months of age at diagnosis. Two patients had thalamic tumors, one had a posterior fossa primary, and the rest had ventricular(More)
Clinical diagnosis of olivopontocerebellar atrophy (OPCA) must be confirmed by radiologic demonstration of atrophy in an appropriate distribution. OPCA may be associated with degeneration of other systems in multisystem atrophy (MSA). The authors report 23 cases of OPCA, eight of which were associated with MSA. Atrophy involved the cerebellum, pons, and(More)
OBJECTIVES To compare the results of serial neuropsychologic testing in children with sickle cell disease with the results of serial magnetic resonance imaging (MRI) examinations, particularly to evaluate neuropsychologic function in the absence of overt stroke. STUDY DESIGN In the Cooperative Study of Sickle Cell Disease, serial neuropsychologic and MRI(More)
The authors represent a cooperative group of 15 institutions that examined the feasibility of using metabolic features observed in vivo with 1H-magnetic resonance (MR) spectroscopy to characterize brain tumors of the glial type. The institutions provided blinded, centralized MR spectroscopy data processing long with independent central review of MR(More)
Findings on cranial magnetic resonance (MR) images were correlated with known histopathologic findings in 42 patients with tuberous sclerosis (TS), 17 of whom received gadopentetate dimeglumine, to extend the range of signs on MR images. Four neuroradiologists recorded the number, sites, configurations, and relative signal intensities of intracranial(More)
PURPOSE To test the feasibility of pediatric perfusion imaging using a pulsed arterial spin labeling (ASL) technique at 1.5 T. MATERIALS AND METHODS ASL perfusion imaging was carried out on seven neurologically normal children and five healthy adults. The signal-to-noise ratio (SNR) of the perfusion images along with T1, M(0), arterial transit time, and(More)