Purpose:
We have previously shown that femtosecond laser pulses tuned to 1.7 µm can be used to create partial thickness channels in cadaver eyes to drain aqueous into the sub-conjunctival space, without damage to the overlaying episclera or conjunctiva [1]. A requirement for clinical evaluation of this technology is in-vivo non-invasive post-operative evaluation of channel patency. We now present in-vivo OCT-based post-operative monitoring and evaluation of such channels created in the rabbits using our customized image enhancement, 3D visualization and analysis software tool.
Methods:
3D OCT images of sub-scleral channels were acquired immediately after surgery (day 0), and on post-operative days 1, 4, 7 and 13. Spectral-domain OCT, customized image enhancement and volume rendering and analysis software tool were used for in-vivo imaging and monitoring of the healing process of the channels in 5 operated rabbits. Standard histology was also performed for comparison with the in-vivo images.
Results:
Fig. 1 shows an example of the healing process of the channel as observed with OCT imaging, with loss of channel patency from days 4 to 7. Customized image enhancement and virtual calipers in our analysis software tool were used to study the dimensions of the channels at different stages of the healing process.
Conclusions:
Non-invasive in-vivo monitoring and evaluation of the healing process of partial thickness scleral drainage channels created with femtosecond laser is practical with appropriate image enhancement. Such techniques should be useful for human clinical testing of this and other surgical techniques.[1] Juhasz T., "The effect of femtosecond laser scleral treatments on the outflow of aqueous humor", In Investigative Ophthalmology & Visual Science (ARVO Meeting Abstract), 45: U392-U392 1052 Suppl. 1, APR 2004.
Keywords: imaging/image analysis: non-clinical • wound healing • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)