title: Differential servo-oscillometry: a novel method for continuous non-invasive estimation of the viscoelastic properties of peripheral arteries
reg no: ETF5280
project type: Estonian Science Foundation research grant
subject: 2.13. Biomedical Engineering
3. Medical Sciences
status: completed
institution: University of Tartu
head of project: Rein Raamat
duration: 01.01.2002 - 31.12.2004
description: The estimation of vascular viscoelastic properties is a rapidly developing branch of cardiovascular diagnostics. At the same time there is a deficiency in non-invasive methods and devices for the arterial compliance (elasticity) measurement, commonly accepted by clinicians.
The aim of this project is to provide a new effective method and device for continuous non-invasive measurement of dynamic (beat-to-beat) arterial compliance. The proposed differential servo-oscillometric method is based on the differential oscillometric two-cuff blood pressure measurement, introduced by our group for finger mean blood pressure estimation. Controlling the counter pressure in the cuffs, one can get two simultaneously recorded volume oscillations during every cardiac cycle. By successive iterations and necessary calibration procedures, it is possible to calculate the non-linear pressure-volume relationship (i.e. compliance) for every cardiac cycle. We understand that the problem is complicated because of viscoelastic environment such as an arterial wall. However, the preliminary experiments have been encouraging. An advantage of the new differential servo-oscillometric analyser is a large range of pressure changes, being twice wider than that of a conventional instrument. It covers also the situation of a free (unloaded) arterial wall, known to be extremely informative for earlier vascular diagnostics.
The project involves a development of a new method and device for non-invasive vascular research, and its clinical approbation in Tartu University Hospital, Department of Cardiology. Joint clinical studies will be conducted in Kuopio University Hospital, Department of Clinical Physiology, and the Centre of Basic Medical Sciences, University of Oslo.

project group
no name institution position  
1.Kersti JagomägiDept of PhysiologySen researcher 
2.Boriss KudimovDept of PhysiologyPhD student 
3.Rein RaamatUniversity of TartuSen Researcher 
4.Jaak TaltsDept of PhysiologyPhD student