Search

Purpose: To examine big-bubble (BB) formation success rates in deep anterior lamellar keratoplasty (DALK) at various corneal depths using real-time guidance from swept-source, microscope-integrated optical coherence tomography (SS-MIOCT)., Methods: The DALK procedure was performed ex vivo with 34 human donor corneoscleral buttons on pressurized artificial anterior chambers using the BB technique employed by Anwar and Teichmann. We inserted a needle under controlled ex vivo conditions to corneal depths ranging from 40% to ≥90% using real-time guidance from SS-MIOCT and injected air. BB success was then determined for each injection., Results: The average needle depth for successful full BB formation was 79.9% ± 3.0% compared with 66.9% ± 2.6% for partial BB formation and 49.9% ± 3.4% for no BB formation (P < 0.0001). Expressed as stroma below the needle tip, this corresponded to 123.9 ± 20.0 μm for successful full BB formation compared with 233.7 ± 23.8 μm for partial BB formation and 316.7 ± 17.3 μm for no BB formation (P < 0.0001). All other variables tested (sex, race, age, endothelial cell density, air injected, needle angle, and central corneal thickness) did not significantly affect BB formation success rates., Conclusions: BB formation in DALK is more successful if needle insertion and air injection occur at deeper corneal depth. However, ≥90% corneal depth was not necessary in this ex vivo model of DALK. SS-MIOCT can be used to accurately guide the needle in real time., Competing Interests: For the remaining authors no conflicts of interest were declared.

Purpose: To report the intraoperative use of microscope-integrated optical coherence tomography (MIOCT) to enable visualization for Descemet's stripping automated endothelial keratoplasty (DSAEK) in 2 patients with advanced bullous keratopathy., Methods: Patient 1 was an 83-year-old female and patient 2 was a 28-year-old male both with limited vision and significant pain from bullous keratopathy who underwent palliative DSAEK. Because of the severity and chronicity of the corneal decompensation in both patients, the view past the anterior cornea was negligible using standard microscope illumination techniques. We used spectral-domain (Patient 1) and swept-source (Patient 2) MIOCT, both of which rely on infrared illumination, to visualize key parts of the DSAEK procedure., Results: Graft insertion, unfolding, tamponade, and attachment could be dynamically visualized intraoperatively despite the nearly opaque nature of the host corneas. Postoperatively, the grafts remained attached with significant corneal clearing, and there was improvement in visual acuity, and pain relief for both patients., Conclusions: MIOCT is a valuable tool for the corneal surgeon, allowing for DSAEK to be successfully performed even when the surgical microscope view is limited from severe corneal edema, as is often the case in patients with advanced bullous keratopathy. By using MIOCT, these patients can benefit from the advantages of DSAEK despite a clinically opaque cornea, which would otherwise be treated with a penetrating keratoplasty.