title: Automated determination of the right ventricular ejection fraction by digital processing of 81mKr scintigrams.
abstract: A method is presented for the automated determination of the right ventricular ejection fraction (RVEF) by digital image processing of scintigrams obtained by intravenous infusion of Krypton 81m (81mKr) dissolved in a glucose solution. End-diastolic and end-systolic sum pictures were computed by the addition of approximately 30-40 frames selected from the time-activity curve of a preliminary, manually drawn, right ventricular region of interest. After processing these two images with an adaptive Wiener filter, the right ventricular contour was determined by a recently developed algorithm using morphological and functional criteria. The RVEF was calculated for a series of 51 patients from the counts in the detected right ventricular regions in the end-diastolic and end-systolic sum images. In 16 patients without evidence of cardiopulmonary disease, the mean RVEF was 50 +/- 6.1%. RVEF was significantly reduced in 18 patients with obstructive pulmonary disease (42 +/- 6.5%) and in 17 patients with congestive cardiomyopathy (36 +/- 7.1%). The correlation coefficient between two determinations of the RVEF was r = 0.94. Through digital image processing, the determination of the RVEF by radioventriculography with 81m Kr showed high reliability and reproducibility.
mesh_terms: D000465:Algorithms; D002311:Cardiomyopathy, Dilated / Q000503:physiopathology; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007726:Krypton; D008173:Lung Diseases, Obstructive / Q000503:physiopathology; D011868:Radioisotopes; D011877:Radionuclide Imaging; D013318:Stroke Volume
chemical_list: D011868:Radioisotopes; D007726:Krypton