Journal of Biomedical Optics / Volume 16 / Issue 8 / JBO Letters Comparative study of the angle-resolved backscattering properties of collagen fibers in bovine tendon and cartilage

摘要

Brachytherapy is a form of radiation therapy commonlynused in the treatment of prostate cancer whereinnsustained radiation doses can be precisely targeted to thentumor area by the implantation of small radioactive seedsnaround the treatment area. Ultrasound is a popular imagingnmode for seed implantation, but the seeds are difficult to distinguishnfrom the tissue structure. In this work, we demonstratenthe feasibility of photoacoustic imaging for identifyingnbrachytherapy seeds in a tissue phantom, comparing the receivednintensity to endogenous contrast.We have found thatnphotoacoustic imaging at 1064 nm can identify brachytherapynseeds uniquely at laser penetration depths of 5 cm innbiological tissue at the ANSI limit for human exposure withna contrast-to-noise ratio of 26.5 dB. Our realtime combinednphotoacoustic-ultrasound imaging approach may be suitablenfor brachytherapy seed placement and post-placementnverification, potentially allowing for realtime dosimetry assessmentnduring implantation.