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Biomedical subjects

J W Bull

Publications and source records attributed to J W Bull.

At least 19 recordsLinked to original sources

Computerized tomography (the EMI Scanner): a comparison with pneumoencephalography and ventriculography.

Computerized tomography, using the EMI Scanner, allows the diagnosis of cerebral atrophy or hydrocephalus to be made with the same degree of accuracy as conventional neuroradiological methods. Ventricular measurements made on EMI scans have been compared with those from pneumoencephalograms and ventriculograms. A range of normal ventricular measurements for the EMI scan is suggested.

Adolescent↗

A comparison of computer asisted tomography (EMI scanner) with conventional neuroradiologic methods in the investigation of patients clinically suspected of intracranial tumor.

Computerized tomography has been used as the initial radiologic investigation among 212 intracranial tumor suspects. Ninety-five of these patients were ultimately shown to have tumors as a result of all their investigations. Eighty tumors were clearly defined by EMI scanning, four further scans were suspicious but not unequivocally abnormal and six scans showed complications of the tumor rather than the lesion itself. Thus, only five scans were falsely negative in the presence of a tumor. The false positive and false negative rates for EMI scanning have been compared with conventional techniques and computerized tomography shown to compare favourably with angiography or encephalography.

Brain Neoplasms↗

Symptomatic vertebral haemangiomas.

Eight cases of vertebral haemangioma causing spinal cord or nerve root compression are described, together with one other which was not causing organic signs or symptoms. The compression was due to extradural tumour in 5 cases, bony expansion encroaching on the neural canal in 2 cases, and a combination of bony expansion and extradural tumour in one case. When present the classical radiological appearance of accentuated vertical striation or honeycomb pattern is easily recognized, but atypical features, such as apparent pedicular erosion, paravertebral soft tissue mass and bony expansion, may occur, making diagnosis more diffcult. In 2 cases the correct diagnosis was not made before surgery. In one of these there were no plain film changes and in the other a metastasis was considered the more likely diagnosis. In the asymptomatic case the absence of extra-osseous extension was an important factor in excluding any possible clinical significance of the haemangioma. The great importance of pre-operative spinal angiography is stressed.

Adult↗

Radiology in the diagnosis of colloid cysts of the third ventricle.

A series of 38 cases of colloid cyst of the 3rd ventricle is described in most of whom the diagnosis, important for curative surgery, was made radiologically. The most useful investigative technique was pneumography, by which the tumour was outlined in almost all cases. The lateral "hanging head" projection generally demonstrated the lesion most satisfactorily. Care in manipulating air introduced at ventriculography through the foramina of Monro into the 3rd ventricle was frequently rewarded by clear definition of the tumour. In more than one-third of the cases, the lateral plain skull radiograph showed truncation of the dorsum sellae indicative of chronic obstructive hydrocephalus, and, in the large majority of these, pneumography confirmed that the 3rd ventricle, rather than the interventricular foramen, was the site of obstruction to the drainage of cerebrospinal fluid. Carotid angiography, showing hydrocephalus, and in the same cases elevation and lateral displacement of the anterior portion of the internal cerebral veins yielded strong supportive evidence. Vertebral angiography was less specific, and isotope scanning was quite unhelpful.

Adult↗

What is diagnostic radiology's place in medicine?

The question that the title of this lecture poses must depend considerably on the attitude of physicians and surgeons. I have indicated the very low position diagnostic radiology holds in this country relative to our peers in medicine elsewhere.If its improvement is considered to be warranted, we must:(1) Interest medical students at the beginning of their career.(2) Bear in mind that radiologists are likely to be able to teach some anatomy but the reciprocal seldom applies.(3) Obtain chairs in radiology, which are desperately needed.(4) Obtain the acceptance by the medical establishment of the proper place of radiology in clinical medicine.(5) See to the reduction in numbers of unnecessary x-ray examinations.(6) Press for the improvement and enlargement of radiological departments with proper provision for expansion.

Anatomy↗

Effect of changes in cerebral blood flow on proportion of high and low flow tissue in the brain.

Regional cerebral blood flow was measured by injection of (133)Xenon into the internal carotid artery in 11 patients with cerebrovascular disease. All patients were studied under general anaesthesia, first at normocapnia and then at hypocapnia. The 15 minute isotope clearance curves were analysed by computer by two-compartmental analysis and regional changes in flow and the proportions of fast and slow clearing tissue obtained at two levels of arterial CO(2) tension. Hypocapnia caused a fall in blood flow which was consistently accompanied by a decrease in the proportion of fast clearing tissue. Regional changes were not significantly different from the hemisphere mean changes. There was no correlation between changes in blood flow through grey matter and the proportion of fast clearing tissue on a hemisphere mean basis, but on regional analysis the data from 10 out of the 11 patients showed that in areas where blood flow through grey matter changed most the proportion of fast clearing tissue changed least and vice versa. A hypothesis has been proposed to explain this phenomenon.

Adult↗