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 Bioljournal_title
Physics in medicine and biologyauthors
Konings MK,van Leeuwen TG,Mali WP,Viergever MAdoi
10.1088/0031-9155/43/5/001subject
Has Abstractpub_date
1998-05-01 00:00:00pages
1049-57issue
5eissn
0031-9155issn
1361-6560journal_volume
43pub_type
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