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We recently reported on three young patients with severe impairments of episodic memory resulting from brain injury sustained early in life. These findings have led us to hypothesize that such impairments might be a previously unrecognized consequence of perinatal hypoxic-ischaemic injury. Neuropsychological and quantitative magnetic resonance(More)
Children who have suffered extensive unilateral brain injury early in life may show a remarkable degree of residual sensorimotor function. It is generally believed that this reflects the high capacity of the immature brain for cerebral reorganization. In this study, we investigated 17 patients who had undergone hemispherectomy for relief from seizures;(More)
OBJECTIVE To determine the 1H MRS findings in patients with intractable temporal lobe epilepsy (TLE) who had no detectable abnormality on either qualitative or quantitative MRI. BACKGROUND Previous work has indicated that approximately 20% of patients with TLE remain MRI negative after extensive qualitative and quantitative investigation. Single-voxel 1H(More)
Two magnetic resonance imaging techniques, diffusion and perfusion imaging, are being used increasingly for evaluation of pathophysiology of stroke. This article introduces these techniques and reports some initial studies using these approaches, together with conventional T2-weighted magnetic resonance imaging, for investigation of childhood stroke. It is(More)
Subject motion during diffusion-weighted interleaved echo-planar imaging causes k-space offsets which lead to irregular sampling in the phase-encode direction. For each image, the k-space shifts are monitored using 2D navigator echoes, and are shown to lead to a frequent violation of the Nyquist condition when an ungated sequence is used on seven subjects.(More)
The importance of diffusion-weighted MRI in the assessment of acute stroke is well-recognized, and quantitative maps of the apparent diffusion coefficient (ADC) are now widely used. Echoplanar imaging provides a robust method of acquiring diffusion-weighted images free of motion artifact. However, initial experience with clinical MRI systems indicates that(More)
Apparent diffusion coefficient maps of two patients with cyclosporine-induced neurotoxicity showed areas of increased diffusion that corresponded to the characteristic regions of signal change on routine T2-weighted sequences. The majority of lesions subsequently resolved without residual T2 or diffusion signal alteration. These findings suggest that, in(More)
Six affected members of two families with familial periodic cerebellar ataxia were relieved of their symptoms with oral acetazolamide. Phosphorus 31 (31P) nuclear magnetic resonance spectroscopy showed abnormal intracellular pH levels in the cerebellum of all subjects when they were not treated. These levels returned to normal with treatment. Cerebral pH(More)
We have studied the metabolism of 31P-containing metabolites of post-menopausal breast cancers in vivo using magnetic resonance spectroscopy (MRS) and a 5.5 cm surface coil. Spectra were acquired from 23 diameter. The spectra of the 19 previously untreated tumours had significantly higher phosphomonoester (PME) 31P relative peak areas than the normal(More)
Single-shot diffusion-weighted echo-planar imaging (EPI) is typically used for most clinical diffusion studies due to its low sensitivity to patient motion. Although the Nyquist ghost artifact in EPI can be substantially reduced, there is frequently a residual ghost with low signal intensity. As reported in this study, this residual ghost can produce severe(More)