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P Cosgriff

Publications and source records attributed to P Cosgriff.

6 recordsLinked to original sources
PubMed1994

Measurement of the extravascular concentration of renal agents following intravenous bolus injection.

The extravascular concentration (Ce) of some renal agents, in relation to the simultaneous plasma concentration (Ci), was calculated as a function of time after intravenous injection. Four agents were studied: 51Cr-ethylenediamine tetraacetate (EDTA) (n = 11), 125I-hippuran (n = 11), 99Tcm-dimercaptosuccinic acid (DMSA) (n = 11) and 99Tcm-mercaptoacetyl triglycine MAG3 (n = 20). Plasma clearance curves were constructed from data acquired from multiple blood sampling and fitted with two exponentials. The extravascular content of tracer at any time is equal to the injected dose remaining after subtraction of the intravascular tracer content and the total amount of tracer cleared from plasma. Mean Ce/Ci at equilibrium (defined as the time, > 120 min, when Ce/Ci reaches its maximum value) was 1.087 (S.D. 0.019) for EDTA, 1.73 (0.48) for hippuran, 0.37 (0.2) for DMSA and 0.64 (0.3) for MAG3. Corresponding clearance (F) values were 68 (13), 415 (149), 15.6 (9.5) and 214 (52) ml min-1 1.73 m-2. Ce/Ci correlated with F and was also related to protein binding in plasma. Extrapolation of the regressions of Ce/Ci on F to F = 0 at several time points after injection gives a curve of Ce/Ci (at F = 0) against time which represents the rate of equilibration of the tracer throughout its distribution volume that would be seen with zero clearance, and therefore allows measurement of the in vivo protein binding of the tracer in plasma. Protein binding was zero for EDTA, 30% for hippuran, 86% for DMSA and 88% for MAG3.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

User requirements for information systems in nuclear medicine.

In the field of COST cooperation (COST = European Cooperation in the Field of Scientific and Technical Research) a project B2 for Quality Assurance in Nuclear Medicine Software has been established. In a memorandum of understanding setting up this project, user requirements were to be defined for the hardware and software used for data acquisition, processing and presentation. A subgroup of the management committee of COST B2 were interested in the Advanced Informatics in Medicine, AIM, task T-734 'Quality Assurance of Medical Software', and the AIM Project 'A 1034', coordinated by Dr K. Britton, was initiated. The initial drafts of this document were written in Helsinki during 1988-1990, and submitted for comment by the members of the management committee of COST B2. These comments were integrated in the text and this document was finalized by the UK group so as to make it available for international discussion. It is anticipated that, after appropriate international discussion, these User Requirements for Information Systems in Nuclear Medicine will be adopted by the management committee of COST B2 as a COST document. Towards these ends, a working group chaired by Dr Britton, including the British and Finnish teams and Ulrich Noelpp from Switzerland, was appointed by the management committee of COST B2 in April 1990. While writing it we have had the pleasure of working with referees from different European hospitals in many countries. We are happy to thank all of them for their valuable contributions.

Europe↗
PubMed1990

A clinical audit of thallium-technetium subtraction parathyroid scans.

Eighty six consecutive thallium-technetium subtraction parathyroid scans performed over a three year period for hypercalcaemia have been evaluated. Twelve had chronic renal failure, 11 had hypercalcaemia due to non-hyperparathyroid causes and in 10 the imaging study was technically inadequate. The remaining 53 technically adequate studies performed for hypercalcaemia clinically thought to be possibly due to hyperparathyroidism have been analysed. Of 20 (38%) positive scans, 13 came to surgery (10 correctly localized parathyroid adenomas, 2 with multiple gland hyperplasia, and 1 papillary carcinoma of the thyroid). Of 33 (62%) negative scans, 9 had surgical exploration on the basis of strong clinical grounds and all had parathyroid adenomas. Multiple biochemical parameters have been assessed in relation to a positive outcome on scan. The adjusted calcium-phosphate product and the ratio of the adjusted calcium-phosphate product to creatinine (Ca x P/Cr) were both significantly lower in the scan positive group (P less than 0.01). The scan positive group had a significantly higher mean level of PTH (P less than 0.001) and lower mean level of phosphate (P less than 0.001). The present experience shows that parathyroid imaging is useful in localizing parathyroid adenomas in 50% of cases (10 out of 19). This figure is at the lower end of the range of previously published results. It is less effective in demonstrating multiple gland hyperplasia. The decision as to whether to undertake surgical exploration when the scan is negative has been based successfully on clinical judgement. We feel that an analysis of this nature is important, as it gives insights into the practical relevance of parathyroid imaging in the context of routine clinical work.

Adenoma↗
PubMed1985

Technetium labelled red blood cell scintigraphy in the diagnosis of intestinal haemorrhage.

99m-Technetium labelled red blood cell scintigraphy was used in the investigation of 15 adult patients with suspected small or large bowel bleeding requiring at least five units of blood (mean 14.3 units) and one neonate with rectal bleeding. Scintigraphy was found to be an accurate method of detecting the site of haemorrhage and was superior to angiography. This technique may be of particular value in patients with profuse colonic haemorrhage when the view at colonoscopy is poor.

Adult↗