Biomedical subjects

P Breslau

Publications and source records attributed to P Breslau.

5 recordsLinked to original sources

PubMed1982

Pitfall of venous occlusion plethysmography.

The supposition that the lower limb expands uniformly in circumference during venous occlusion has been investigated. The 3 compartments of the calf were found to be expand to differing degrees depending on the volume of muscle within the compartment. The effect of this phenomenon on the measurement of venous outflow and capacitance using an overlapping strain gauge was assessed. When using an overlapping strain gauge, the anatomical site of overlap was found to alter the measured values of outflow and capacitance by as much as 50%. These errors do not arise with strain gauges designed to fit a small range of limb circumferences, so that no overlap occurs. The reproducibility of plethysmography may be enhanced by attention to the site and degree of overlap of gauges which are designed to fit all sizes of limb. Technicians performing venous occlusion plethysmography should be aware of these variations, so that the examination technique can be standardized.

Acute Disease↗

PubMed1981

Importance of noninvasive ultrasonic-Doppler testing in the evaluation of patients with symptomatic carotid bruits.

An ultrasonic Duplex scanner was used to estimate the site and degree of extracranial arterial disease in two groups of patients with asymptomatic bruits. In the first 100 patients only the extent of disease was assessed with 37% of the sides with bruits having high-grade stenoses (greater than 50% diameter reduction) and one-half having lesions which narrowed the internal carotid artery by less than 50%. Seven percent were found to be normal. The remaining 6% had occlusion of the internal carotid artery. In a second group of 81 patients, the effect of the reported findings of the Duplex scan on patient management was reviewed. Only 13 patients underwent angiography and 11 of these were in patients with high-grade stenoses. Five carotid endarterectomies were performed and in each case, the patient had bilateral high-grade lesions. The implications of this diagnostic approach are discussed as well as the need for prospective studies of patients who present with an asymptomatic bruit.

Arteriosclerosis↗

PubMed1975

Electron microscopical study of a family with myotonia congenita.

Biopsy specimens of skeletal muscle from a family that had three female siblings with clinical features of recessive-type myotonia congenita were examined by light and electron microscopy. Fibers examined by the former technique appeared normal. Although some variation in size and shape of mitochondria and sarcomere fragmentation were focally observed by electron microscopy in affected members, they were also encounted in those without clinical manifestations. Importantly, no changes in sarcolemma, sarcoplasmic reticulum, or transverse tubular system were encountered. Capillary basement membrane thickness was within normal limits. The evidence strongly suggests that myotonia congenita represents an entity distinct from myotonia dystrophica and that its pathogenesis may be related to a biochemical rather than ultrastructal aberration.

Adolescent↗

PubMedDate not supplied

Post-endarterectomy carotid ultrasonic duplex scanning concordance with contrast angiography.

The results of ultrasonic duplex scanning combined with spectral analysis are compared with the results of contrast angiography in patients after endarterectomy in which recurrence of carotid arterial disease was suspected. Thirty-six patients underwent a duplex scan study within 3 months of their post-operative angiogram, performed at their physician's discretion (44 studies). The overall accuracy of the method was 80%. Our ability to predict a greater than 50% diameter reduction along with total occlusion was 94%. The measure of agreement corrected for chance between arteriography and duplex scanning as expressed by the Kappa statistic was 0.675 +/- SE (K) 0.096. This level of agreement compared favorably to that of inter- and intra-observer variability in reading cerebral angiograms. The accuracy reported justifies the clinical use of ultrasonic duplex scanning in the detection of recurrent stenosis after carotid endarterectomy.

Blood Flow Velocity↗

PubMedDate not supplied

Quantitative carotid phonoangiography.

One hundred and sixteen carotid artery bruits were assessed using quantitative phonoangiography (spectral bruit analysis - SBA). This technique uses the averaged break frequency of the bruit to calculate the diameter of he residual lumen at the site of stenosis. Biplanar contrast arteriography was performed on 43 (37%) of the sides. All 116 sides were also evaluated with an ultrasonic Duplex scanner. Ten (8.6%) bruits could not be analyzed by the SBA, leaving 106 sides in which the residual lumen diameter could be estimated. The diameter of the vessel at the site of stenosis estimated by SBA and arteriography were compared and found to agree within 1 mm of each other in 85% of patients. A linear relationship was demonstrated between absolute lumen diameter and percent stenosis as measured from the arteriograms, but we were unable to correlate the absolute diameter of hte residual lumen as assessed by arteriography or SBA with the assessment of the degree of the stenosis derived from spectral analysis of the pulsed Doppler signal. The significance of these findings is discussed with relevance to the clinical application of spectral bruit analysis.

Auscultation↗