title: Arterial flow characterization with a photodiode array based imaging system.
abstract: An x-ray imaging system is described that can be used for obtaining arterial blood flow information. The system consists of a linear photodiode array image detector, simple optical and mechanical components, and a data acquisition microcomputer that connect to a conventional x-ray image intensifier based fluorography system. Flow information is obtained by detecting the movement of a small, locally injected bolus of radio-opaque contrast agent. This is done by determining the bolus mass, integrated over the cross-sectional area, at each of 1024 positions along the length of the artery with a sampling rate of up to 200 samples per s. It is shown in a phantom study that the peak flow velocity can be measured with an accuracy of +/- 5% by detecting the bolus arrival times at each of the 1024 positions. The mean velocity is obtained with similar accuracy using a cross-correlation technique and a modified form of the Stewart-Hamilton principle. In addition, it is shown that the separation and reattachment points resulting from flow separation near a stenosis can be determined from the bolus clearance times. The locations of these points are consistent with theoretical values for the cosine shaped symmetric 89% stenosis used in this study.
authors.affiliation: Imaging Research Laboratories, John P. Robarts Research Institute, London, Ontario, Canada.
authors.forename: I A
authors.initials: IA
authors.lastname: Cunningham
authors.forename: S
authors.initials: S
authors.lastname: Yamada
authors.forename: B B
authors.initials: BB
authors.lastname: Hobbs
authors.forename: A
authors.initials: A
authors.lastname: Fenster
mesh_terms: D000792:Angiography / Q000295:instrumentation / Q000379:methods*; D001157:Arterial Occlusive Diseases / Q000503:physiopathology*; D001775:Blood Circulation; D001783:Blood Flow Velocity; D006801:Humans; D007201:Indicator Dilution Techniques; D008961:Models, Structural; D012666:Semiconductors