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Title: Asymptomatic pulmonary embolism: a common event in high risk patients

Abstract

Ventilation and perfusion lung scans were obtained before and at weekly intervals following hip surgery or major amputation in 158 patients. Pulmonary arteriograms were obtained in 21 of 33 patients developing perfusion patterns strongly suggesting embolism; 19 of the 21 arteriograms demonstrated pulmonary embolism. From autopsy and clinical data, 36 patients were diagnosed as having an embolus while under study, and 12 patients were suspected of having had an embolus during their illness but prior to entry into the study. Only four of these 48 patients experienced symptoms suggestive of pulmonary embolism. We conclude that asymptomatic pulmonary embolism is a common event in the populations studied.

Authors:
; ;
Publication Date:
Research Org.:
University of South Florida College of Medicine and James A. Haley Veterans Administration Hospital, Tampa
OSTI Identifier:
5639329
Resource Type:
Conference
Resource Relation:
Journal Name: Ann. Surg.; (United States); Journal Volume: 195:3
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; BIOMEDICAL RADIOGRAPHY; DIAGNOSTIC USES; IMAGE SCANNERS; BLOOD VESSELS; DIAGNOSIS; EMBOLI; ISOMERIC NUCLEI; LUNGS; PATIENTS; RADIOISOTOPE SCANNING; TECHNETIUM 99; XENON 133; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; BODY; CARDIOVASCULAR SYSTEM; COUNTING TECHNIQUES; DAYS LIVING RADIOISOTOPES; DIAGNOSTIC TECHNIQUES; EVEN-ODD NUCLEI; HOURS LIVING RADIOISOTOPES; INTERMEDIATE MASS NUCLEI; INTERNAL CONVERSION RADIOISOTOPES; ISOMERIC TRANSITION ISOTOPES; ISOTOPES; MEDICINE; NUCLEAR MEDICINE; NUCLEI; ODD-EVEN NUCLEI; ORGANS; RADIOISOTOPES; RADIOLOGY; RESPIRATORY SYSTEM; TECHNETIUM ISOTOPES; USES; XENON ISOTOPES; YEARS LIVING RADIOISOTOPES; 550601* - Medicine- Unsealed Radionuclides in Diagnostics

Citation Formats

Williams, J.W., Eikman, E.A., and Greenberg, S. Asymptomatic pulmonary embolism: a common event in high risk patients. United States: N. p., 1982. Web.
Williams, J.W., Eikman, E.A., & Greenberg, S. Asymptomatic pulmonary embolism: a common event in high risk patients. United States.
Williams, J.W., Eikman, E.A., and Greenberg, S. Mon . "Asymptomatic pulmonary embolism: a common event in high risk patients". United States. doi:.
@article{osti_5639329,
title = {Asymptomatic pulmonary embolism: a common event in high risk patients},
author = {Williams, J.W. and Eikman, E.A. and Greenberg, S.},
abstractNote = {Ventilation and perfusion lung scans were obtained before and at weekly intervals following hip surgery or major amputation in 158 patients. Pulmonary arteriograms were obtained in 21 of 33 patients developing perfusion patterns strongly suggesting embolism; 19 of the 21 arteriograms demonstrated pulmonary embolism. From autopsy and clinical data, 36 patients were diagnosed as having an embolus while under study, and 12 patients were suspected of having had an embolus during their illness but prior to entry into the study. Only four of these 48 patients experienced symptoms suggestive of pulmonary embolism. We conclude that asymptomatic pulmonary embolism is a common event in the populations studied.},
doi = {},
journal = {Ann. Surg.; (United States)},
number = ,
volume = 195:3,
place = {United States},
year = {Mon Mar 01 00:00:00 EST 1982},
month = {Mon Mar 01 00:00:00 EST 1982}
}

Conference:
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  • This report outlines a method of automatically segmenting pulmonary perfusion regions from ultrafast CT data. Segmenting was performed by a k-means clustering of unenhanced, maximal enhancement and both parameters. Time density curves from distinct regions were generated and perfusion determined. In two example subjects with pulmonary embolism hypoperfused regions were identified. In a normal subject slight gravity related gradient hypoperfusion was also detected. These preliminary results suggest that automated segmentation of UFCT pulmonary perfusion scans is possible and could greatly improve the clinical utility of the scanning technology.
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