Bowman's layer transplantation in advanced keratoconus; 18-months outcomes

Purpose To assess the outcome of isolated Bowman's layer transplantation (BLT) in advanced keratoconus in the patients not suitable for ultra violet cross-linking and intra stromal corneal ring segments. Study design Nonrandomized Quasi-Experimental. Materials and methods Mid corneal stromal dissection followed by implantation of manually isolated bowman layer from a donor into the recipient stromal pocket was performed in the Department of Ophthalmology Khyber Teaching Hospital Peshawar from September 2018 to October 2018 and followed up over 18 months. Results Eleven eyes of 11 patients, 8 male and 3 female within the age range of 7-28 years with progressive keratoconus went under BLT All keratometry values decreased after surgery. Mean anterior pre-operative SimK changed from 69.05 +/- 10.85 D to 61.14 +/- 6.23 D at 18 months post-operatively (P = 0.005). Means pre-operative Kmax value decreased from 77.24 +/- 7.58 D to 71.07 +/- 5.37 D at 18 months post-operatively (p = 0.060). The mean pre-operative posterior keratometry value changed from - 10.03 +/- 0.88 to - 8.96 +/- 1.06 D at 18 months post-operatively (P = 0.002). Mean pre-operative thinnest corneal thickness increased from 281.64 +/- 196.86 um to 355.27 +/- 19.17 um at 18th months post-operatively (P = 0.001). Pachymetry p-value pre-operative to 18 months (P = 0.001) was statistically significant. Mean anterior SimK at 6 months post-operatively, 60.55 +/- 5.56D changed to 61.14 +/- 6.23D at 18 months post-operatively (P = 0.000), Kmax at 6 months postoperative 71.60 +/- 5.01 D changed to 71.07 +/- 5.37 D at 18 months post-operatively (P = 0.008). Both anterior K values at 6 months and 18 months post-operatively showed less significant change, and the same was true for Kmax data at 6 months and 18 months post-operatively. P-values at 6 months to 18 months post-operatively for cornea back data remained (P = 0.001) unchanged. No complications were observed intra-operatively or post-operatively. Conclusion Bowman layer transplantation is a unique surgical treatment for advanced keratoconus to stabilize progressive ectasia with fewer complications avoiding the need for penetrating or deep anterior lamellar keratoplasty.

Automated summary

Bowman's layer transplantation is a unique surgical treatment for stabilizing progressive ectasia in advanced keratoconus with fewer complications, eliminating the need for penetrating or deep anterior lamellar keratoplasty.