Torsion measurement of catheters using polarized light in a single glass fibre.

Abstract:

:Several types of intravascular ultrasound (IVUS) catheters are connected to a motor at their proximal end, in order to let the catheter rotate around its length axis. However, the rotation of the distal axis tip does not follow exactly the rotation of the motor, since the catheter axis is not completely torsion-free and friction forces cause the tip to rotate in a shockwise manner. In the case of the IVUS catheter, continuous information concerning the exact rotation of the crystal is essential for 3D image reconstruction. We developed a simple method of measuring the tip rotation continuously, the TOMCAT method, using only a single optical fibre glued in a fixed position inside the rotating axis of the IVUS catheter, or any rotating axis or catheter in general. Our method does not require external electromagnetic fields or the presence of a non-rotating guiding catheter. The rotation of the distal tip is related to that of the proximal part by transporting polarized light through the fibre. We performed in vitro experiments using various types of optical fibres to test the TOMCAT method, and conclude that using a specific step-index monomode cylinder-symmetrical optical fibre the TOMCAT approach yields accurate results.

journal_name

Phys Med Biol

authors

Konings MK,van Leeuwen TG,Mali WP,Viergever MA

doi

10.1088/0031-9155/43/5/001

subject

Has Abstract

pub_date

1998-05-01 00:00:00

pages

1049-57

issue

5

eissn

0031-9155

issn

1361-6560

journal_volume

43

pub_type

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