D. J. Bryant

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Fluid attenuated inversion recovery pulse sequences with a long echo time (TE) have been used to image the brain in one volunteer and four patients. The long inversion time used with this sequence suppresses the signal from CSF and the long TE produces very heavy T2 weighting. The marked reduction in flow artefact from CSF and the high T2 weighting enabled(More)
A method for determining flow by nuclear magnetic resonance (NMR) imaging is described. A conventional spin-echo imaging sequence is employed with the addition of balanced gradient pulses on either side of the pi radiofrequency pulse. Flow velocities in the direction orthogonal to the image plane are determined by the phase shifts in the NMR image.(More)
Proton magnetic resonance spectroscopy (1H MRS) was performed within 18 h of birth (median 13, range 4-18 h) on 16 term infants with clinical features of birth asphyxia. Ten infants with no evidence of birth asphyxia were studied as controls at 5-18 (median 8) h after birth. To detect delayed impairments in cerebral energy metabolism, 15 infants suspected(More)
All users of NMR equipment are familiar with the desirability of achieving as high a quality of field as possible. On the other hand, it is easy to forget that the field quality of relevance in both imaging and spectroscopy is that over individual voxels, and not the whole volume. This note demonstrates in practice how performance in poor fields is improved(More)
Three patients with four or more follow-up magnetic resonance imaging (MRI) examinations over a 15-22 month period are described to illustrate the differing patterns of follow-up seen with MRI in multiple sclerosis (MS). These cases illustrate patterns of remission, exacerbation and remission, and rapid progression. The value of MRI in the follow-up of MS(More)
The gene responsible for Huntington's disease (HD) has been located, but its action and the pathophysiology of HD remain unclear. Glutamate excitotoxicity may contribute to the striatal neurodegeneration seen in HD. We used localised proton magnetic resonance spectroscopy (MRS) of the brain to investigate five patients with early HD, one symptom-free gene(More)
The purpose of this study was to correlate the hyperintensity in the globus pallidus seen on T1-weighted magnetic resonance imaging (MRI) of the brain in chronic liver disease with changes in metabolite ratios measured from both proton and phosphorus-31 magnetic resonance spectroscopy (MRS) localised to the basal ganglia. T1-weighted spin echo (T1WSE)(More)
Proton magnetic resonance spectroscopy (1H MRS) was used to investigate intracranial tumours in vitro and in vivo. Biopsy specimens were studied from 47 patients, 11 of whom were also examined in vivo. Analysis was based on the signals from N-acetylaspartate (NAA), phosphocreatine plus creatine (Cr), choline-containing compounds (Cho), alanine (Ala), and(More)
Hepatic phosphorus-31 magnetic resonance spectroscopy (31P MRS) was undertaken in 85 patients with histologically proven cirrhosis of varying etiologies and functional severity. Reference data were acquired from 16 healthy volunteers who had no history or evidence of liver disease or alcohol abuse. In vivo hepatic 31P MR spectra were acquired with pulse(More)
A technique for assessing brain perfusion with magnetic resonance (MR) imaging is described. This technique uses two spin echo sequences that are identical except that the second is sensitised to blood flow by use of a pair of unipolar gradients on either side of the 180 degree pulse. Differences in phase between the two sequences are displayed with a(More)