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R J Ordidge

Publications and source records attributed to R J Ordidge.

64 records · Page 4Linked to original sources
PubMed1987

Real-time movie imaging from a single cardiac cycle by NMR.

Using a 1-m-bore superconductive magnet at 0.1 T, whole-body transverse images through adult humans have been obtained at repetition times of 57 ms. The techniques used were minor variations of echo-planar imaging (EPI) employing large pulsed gradients to provide complete coverage of the plane in phase space, and low-angle RF excitation sequences allowing rapid repetition of the experiment. In addition active magnetic screening of the gradient coils was implemented to protect the surrounding magnet from the eddy currents induced by the necessarily fast switching of the large gradient fields.

Adult↗
PubMed1987

Natural abundance 13C NMR spectrum of glycogen in humans.

In vivo NMR has focused on using 31P and 1H to study metabolism in humans. Comparable 13C NMR studies have not been undertaken, presumably, because of its insensitivity. We report herein that the natural abundance 13C signal from C1 glycogen is observable. The ability to observe the signal opens new opportunities to noninvasively study glycogen metabolism in man.

Humans↗
PubMed1986

Measurement of T1 by echo-planar imaging and the construction of computer-generated images.

The high-speed echo-planar imaging (EPI) technique is used to obtain rapid T1 and spin density measurements by a two-point method. It is shown that neglect of edge effects in the slice selection procedure leads to significant systematic errors in T1. T1 maps for two young patients, obtained at 4.0 MHz, are presented. The T1 and spin density values obtained are used to produce computer-generated images in inversion recovery simulations. These results demonstrate marked improvement in image contrast without paying the time penalty incurred in real experiments, thereby greatly increasing patient throughput potential.

Abdomen↗
PubMed1980

Human whole body imaging and detection of breast tumours by n.m.r.

A brief review of recent developments in line scan imaging of large objects is given, together with some representative images showing anatomical detail and a discussion of some spin-lattice relaxation time mapping results. Current progress in high speed imaging by means of the echo planar technique is reported and some preliminary results obtained at both 15.0 and 4.0 MHz are discussed.

Breast Neoplasms↗