Laser interstitial thermotherapy (LITT) monitoring using high-resolution digital mammography: theory and experimental studies

• Published in: Physics in medicine & biology Vol. 47; no. 16; pp. 2987 - 2999
• Main Authors: Minhaj, Ahmed M, Manns, Fabrice, Milne, Peter J, Denham, David B, Jr, Nelson Salas, Nose, Izuru, Damgaard-Iversen, Karsten, Parel, Jean-Marie, Robinson, David S
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 21.08.2002; Institute of Physics
• Subjects: Adipose Tissue - diagnostic imaging; Adipose Tissue - surgery; Animals; Biological and medical sciences; Breast Neoplasms - diagnostic imaging; Breast Neoplasms - therapy; Cadaver; Feasibility Studies; Hot Temperature; Hyperthermia, Induced - instrumentation; Hyperthermia, Induced - methods; Laser Therapy - instrumentation; Laser Therapy - methods; Mammography - instrumentation; Mammography - methods; Medical sciences; Models, Biological; Phantoms, Imaging; Radiographic Image Enhancement - methods; Sensitivity and Specificity; Subtraction Technique; Surgery, Computer-Assisted - methods; Swine
• ISSN: 0031-9155; 1361-6560
• DOI: 10.1088/0031-9155/47/16/313

Laser interstitial thermotherapy (LITT) is a minimally-invasive laser hyperthermia procedure for the treatment of localized tumours. Real-time monitoring of LITT is essential to control the extent of tumour destruction and ensure safe and effective treatments. The feasibility of using high-resolution digital x-ray mammography to monitor LITT of breast cancer was evaluated. Tissue phantoms including polyacrylamide hydrogel and cadaver porcine tissue were heated using a 980 nm diode laser delivered through optical fibres with diffusing tips. Digital images of the tissue phantoms were recorded with a high-resolution digital stereotactic breast biopsy system during heating. The recorded images were processed and analysed to detect heat-induced changes. No changes were detected during heating of the hydrogel. Pixel-by-pixel subtraction of the initial image from images taken during laser heating shows observable thermally-induced changes around the fibre during laser irradiation that correlate with the thermal denaturation zone observed by gross anatomy. These experiments demonstrate that high-resolution digital x-ray mammography can be used to detect heat-induced tissue changes during experimental LITT in fibro-fatty tissue.