Share Email Print

Proceedings Paper

Imaging of interstitial laser photocoagulation of liver tumors
Author(s): Zahir Amin; J. J. Donald; Margret A. Hall-Craggs; Martyn Paley; William R. Lees; Stephen G. Bown
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Imaging plays a crucial role in the treatment of liver tumors by interstitial laser photocoagulation (ILP). Ultrasound allows location of the tumors and enables guided placement of thin hollow needles (through which the optical fibers are passed) into the appropriate part of the tumor. Heating of the tumor during ILP is seen as an enlarging echogenic zone around the fiber tips. However, the margins of the echogenic zone are often ill-defined and irregular and ultrasound cannot clearly differentiate treated from untreated tumor on follow-up scans. CT (pre-contrast, dynamic, and delayed) is used to define the number and sizes of metastases prior to ILP. 24 hrs after ILP dynamic enhanced CT clearly shows the laser-induced necrosis as a well-defined non-enhancing area, although real-time CT monitoring of ILP shows very little change around the fiber tip. MRI (standard spin-echo sequences) has been used to evaluate lesions post-ILP. On T1-weighted images the lesions appear heterogenous with areas of high and low signal intensity. With these current sequences the lesion-to-liver contrast is not as good as with dynamic enhanced CT. Conclusion: Ultrasound plays a useful role in treatment delivery. At present the post-ILP evaluation is best performed using CT. MRI has the potential for real-time monitoring of ILP using temperature sensitive sequences.

Paper Details

Date Published: 7 July 1993
PDF: 7 pages
Proc. SPIE 1882, Laser-Tissue Interaction IV, (7 July 1993); doi: 10.1117/12.147662
Show Author Affiliations
Zahir Amin, National Medical Laser Ctr./Univ. College London, and Middlesex Hospital (United Kingdom)
J. J. Donald, Middlesex Hospital (United Kingdom)
Margret A. Hall-Craggs, Middlesex Hospital (United Kingdom)
Martyn Paley, Middlesex Hospital (United Kingdom)
William R. Lees, Middlesex Hospital (United Kingdom)
Stephen G. Bown, National Medical Laser Ctr./Univ. College London (United Kingdom)

Published in SPIE Proceedings Vol. 1882:
Laser-Tissue Interaction IV
Steven L. Jacques; Abraham Katzir, Editor(s)

© SPIE. Terms of Use
Back to Top