Abstract
Purpose :
Femtosecond laser image guided, high-precision trabeculotomy (FLigHT) is an emerging non-invasive glaucoma treatment. The potential collateral effects on surrounding tissues are not currently understood. We performed an experimental study in human cadaver eyes to learn about collateral damage during FLigHT.
Methods :
A custom artificial anterior chamber and sample holder with an integrated thermocouple was used to measure the temperature rise in human cadaver trabecular meshwork during FLigHT. A second thermocouple measured ambient temperature to serve as a control. A finite element model was developed to predict heating during FLigHT. Histology with hematoxylin and eosin (H&E) staining was performed under light microscopy to assess thermal collateral damage to tissue surrounding the treatment location. A control region of trabecular meshwork taken from the same H&E-stained sample was also imaged for comparison.
Results :
The maximum temperature rise (ΔT) was 2.8±0.26 °C above baseline 2.4 seconds after the initiation of treatment (Figure 1). The average temperature rise during the treatment was 1.98±0.33 °C above baseline. The finite element model predicted a maximum temperature rise of 2.5°C. Histology at 400x magnification showed continuous eosin-stained collagen fibers along the outer wall of the Schlemm’s canal and into the FLigHT region; hematoxylin-stained nuclei were also visible along the outer wall of Schlemm’s canal in the FLigHT channel (Figure 2). Trabecular beams were identified in the TM distal to the treatment area.
Conclusions :
The temperature rise in the tissue adjacent to the FLigHT procedure was within acceptable limits. The histology of the FLigHT sample supports this claim revealing an overall tissue architecture like that of the control sample. Collateral damage is minimal.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.