Nuclear Medicine Technology and Other Health Applications Early Detection and Localization of Project Title: 18. Pulmonary Tinpairmence Expeceed Results in FY_1975: RX¥-O1-03-(£) Since the basic screening procedure will simply indicate the presence it is hoped to make it more specific by differen- tiating among the various obstructive lung discases using trained subjects with respiratory disease. It is thought that the difference in diffusion rates of each gas in a mixed gas tracer, coupled with the effects on diffusion of variations in volumes and tissue elasticity and of gas flow rates resulting from obstructions in the air passages, can be monitored by lung scanning and analysis of the expirate at the mouth to predict the type and extent of obstructive disease. This study will be preceded by work with healthy subjects using artifacts that mimic flow restrictions and other conditions to establish refcrence conditions. <A bench-scale plastic mock-up of pertinent parts of the bronchial tree will be constructed and used to study these conditions outside the body and to predict the in vivo results. Instrumentation will be developed for precise automatic control and timing of the steps in the process, including helium injection, and on-line data processin*, computation, and analysis with a portable mini-computer leading to decisions concerning the patient while he is still present. 19. Description and Explanation of Major Materials, contract Items: Capital Equipment for FY 1974: Equipment, and Sub- None. Canital Fauipment for FY 1975: A low resistance spirometer ($2,100) is required to measure the volumes of air during respiration, a nitrogen analyzer ($2,300) to measure residual volume and the functional residual capacity of the lungs, a residual gas analyzer ($3,400) to measure the concentrations in air of other inert gas tracers besides helium, and a pneumotachometer ($2,100) to measure the flow of air during respiration. Instrumentation ($15,000) will be constructed for the semi-automatic acquisition and storage of breathing data on magnetic tape. (In FY 1976, instrumentation estimated to cost $35,000 will be constructed for on-line data proce , computation, and analysis.) 20. blipactions for Related Construction Projects: Propos None. b479251 : (Cont'd) evaluation of regional lung function with xenon 127 for people with lung inpainmment will continuc. or absence of diseasc, ; f