Pentacam-based phototherapeutic keratectomy outcome in superficial corneal opacities

Mohammad A Rashad

Ophthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt

Purpose: This study aimed to evaluate the effectiveness of phototherapeutic keratectomy (PTK) as an alternative treatment to keratoplasty using the Pentacam to assess depth of dense opacities.
Methodology: PTK was performed in eleven eyes of ten patients with superficial corneal opacities after assessment by Scheimpflug images of the Pentacam for central corneal thickness (CCT) and opacity level and depth.
Results: The best-corrected spectacle visual acuity (BCSVA) significantly improved. The preoperative mean logMAR was 0.85 (0.14 decimal equivalent, 6/42 Snellen's equivalent), and the final postoperative mean logMAR was 0.58 (0.26 decimal equivalent, 6/23 Snellen's equivalent). The mean preoperative CCT was 465.64 ± 71.94 µm. The mean programmed ablation depth was 142.09 ± 47.58 µm. The programmed ablation depth was correlated to mean logMAR early (1 month) and not correlated later (6 months). None of the eyes lost lines of BCSVA or developed serious complications, such as keratectasia, delayed epithelialization, or corneal melting.
Conclusion: Corneal scars extending beyond the anterior one-fifth of the cornea can be treated safely and effectively by PTK due to the smoothing effect, with reduction of the cylinder rather than complete opacity removal. This can decrease the need for keratoplasty.

Keywords: phototherapeutic keratectomy, PTK, corneal opacities, Pentacam