Non-contact evaluation of carotid artery flow

Abstract

The problem of diagnosing carotid stenosis has been the interest of many investigators for many years. Most techniques tend to diagnose occlusions up to 5041 of carotid stenosis easily but in smaller than 50% occlusions their record is quite poor. In our experiment we took two approaches. We set out to devise what the expected curve would be from progressive carotid occlusion by using standard mathematical formulas and accepted principles of fluid physics. By devising such a theoretical curve we were then able to measure our experimental results against that.

The second problem we attacked was to develop an electronic system whereby we could diagnose this type of occlusion, particularly below 50%. Using ultrasound propagated through air and employing such electronic techniques as the phase lock loop. we were able to examine the movement of the cornea in a free-running state without any contact.

The result that we obtained were in good agreement with the theoretical curve and we felt it was an advance in the diagnosis of carotid stenosis.