I-OCT GUIDED DALK IN POSTERIOR KERATOCONUS

To present the successful surgical technique and outcome of Intraoperative Optical Coherence Tomography (IOCT)-guided Deep Anterior Lamellar Keratoplasty (DALK) for managing a rare case of Posterior Keratoconus (PKC) with a  visually-significant central stromal opacity and preserved, healthy endothelium.

Cornea and Refractive Surgery Service, Tertiary Eye Care Center.

A 45-year-old male presented with progressive vision loss in the left eye (OS). Best-corrected visual acuity (BCVA) was limited to Counting Fingers (CF).  Clinical and tomographic evaluation confirmed the diagnosis of Posterior Keratoconus, characterized by marked posterior corneal surface ectasia with overlying stromal scarring, while the host endothelial cell density was normal.

The surgical plan was to perform a Big Bubble (BB) DALK. The challenge of achieving adequate dissection depth over the complex and severely altered posterior curvature was managed using real-time IOCT visualization. After initial manual stromal dissection. The recipient's scarred anterior stroma was removed, and an 8.0 mm donor lamellar button was sutured into place. The procedure was completed without DM perforation. At 6 months follow-up, the graft was clear, and the patient's BCVA improved significantly to 20/40.

Manual IOCT-guided DALK is an invaluable and safe technique for managing the complex anatomy of Posterior Keratoconus with visually significant stromal opacification. IOCT allows for the precise localization of the manual dissection minimizing the risk of DM perforation and maximizing the potential for a successful deep lamellar transplant, leading to excellent visual rehabilitation while preserving the host endothelium.