Retinal absorption measurements for laser therapy through interferometric imaging of the thermal expansion
ASSOC RESEARCH VISION OPHTHALMOLOGY INC. 2022
View details for Web of Science ID 000844401303047
- Interferometric imaging of thermal expansion for temperature control in retinal laser therapy BIOMEDICAL OPTICS EXPRESS 2022; 13 (2): 728-743
Interferometric imaging of thermal expansion for temperature control in retinal laser therapy.
Biomedical optics express
2022; 13 (2): 728-743
Precise control of the temperature rise is a prerequisite for proper photothermal therapy. In retinal laser therapy, the heat deposition is primarily governed by the melanin concentration, which can significantly vary across the retina and from patient to patient. In this work, we present a method for determining the optical and thermal properties of layered materials, directly applicable to the retina, using low-energy laser heating and phase-resolved optical coherence tomography (pOCT). The method is demonstrated on a polymer-based tissue phantom heated with a laser pulse focused onto an absorbing layer buried below the phantom's surface. Using a line-scan spectral-domain pOCT, optical path length changes induced by the thermal expansion were extracted from sequential B-scans. The material properties were then determined by matching the optical path length changes to a thermo-mechanical model developed for fast computation. This method determined the absorption coefficient with a precision of 2.5% and the temperature rise with a precision of about 0.2°C from a single laser exposure, while the peak did not exceed 8°C during 1 ms pulse, which is well within the tissue safety range and significantly more precise than other methods.
View details for DOI 10.1364/BOE.448803
View details for PubMedID 35284191
View details for PubMedCentralID PMC8884207