title: Myocardial perfusion imaging using thallium-201: a new algorithm for calculation of background activity.
abstract: A method is presented for calculating a background image to be subtracted from TI-201 myocardial perfusion images. The method was derived from experimental measurements of background components in which hearts of animals injected with TI-201 were replaced with hearts from nonradioactive animals. The algorithm generates a background image that accounts for TI-201 activity in surrounding tissues and within the cardiac chamber. Comparison of the computer-generated background images with background images of the experimental models showed a mean difference of about 3% (range 1-6%). Clinical images using this method of background generation and subtraction are presented.
mesh_terms: D000818:Animals; D002306:Cardiac Volume; D003201:Computers; D004285:Dogs; D006321:Heart / Q000000981:diagnostic imaging*; D007089:Image Enhancement; D010477:Perfusion; D011868:Radioisotopes; D011877:Radionuclide Imaging; D013382:Subtraction Technique; D013793:Thallium / Q000097:blood
chemical_list: D011868:Radioisotopes; D013793:Thallium