Optical Coherence Tomography/Angiography-Guided Tumor Ablation with a Continuous-Wave Laser Diode

Laser ablation can be an effective modality for treatment, but it is complicated to apply continuous-wave (CW) light sources for laser ablation because of the unpredictable photothermal damage. In this study, an integrated theranostic system combining a low-cost CW laser diode with optical coherence tomography (OCT)/angiography (OCTA) was utilized for the in vivo ablation of tumor tissues. To examine the effect of laser exposure on tissue scattering characteristics, the OCT backscattering intensities of non-ablated and ablated tissues were analyzed, and the effect on the skin microvasculature produced by laser ablation was quantitatively evaluated. Moreover, the integrated system and the proposed method were implemented for the treatment of skin tumor on the mouse model. The obtained results indicate that the developed laser ablation system can effectively remove tumor tissues with controllable photodamage under OCT/OCTA guidance and that the system cost may be significantly reduced by using the CW laser diode.