PURPOSE: To examine the role of Bowman's layer (BL) on the nature of anterior corneal regeneration after excimer laser phototherapeutic keratectomy (PTK). METHODS: A cohort of 13 patients underwent PTK to remove either 7 mum of BL for treatment of primary recurrent corneal erosions (RCE; six patients) or complete BL removal (15-mum ablation) to treat RCE or poor vision secondary to map-dot-fingerprint (MDF) dystrophy (seven patients). Clinical examinations and laser-scanning in vivo confocal microscopy (IVCM) were conducted before surgery and at a mean of 4 and 8 months after surgery. RESULTS: Total BL removal resulted in a significant decline in subbasal nerve density at 4 months (P = 0.007) that barely recovered to preoperative levels at 8 months (P = 0.055). With BL partially present, subbasal nerve density did not significantly change from preoperative levels. Superficial, wing, and basal epithelial cell density recovered to preoperative levels within 4 months after PTK, regardless of the presence of BL. Subepithelial keratocytes, however, were more densely distributed in corneas without BL relative to those with a partial BL present (P = 0.005), and increased anterior keratocyte reflectivity was noted in all eyes without BL and in no eye with a partial BL present. CONCLUSIONS: Subbasal nerve regeneration is delayed and subepithelial keratocyte density and reflectivity remain elevated up to 10 months after total BL removal by PTK. The results provide initial evidence for a possible role of BL in facilitating rapid stromal wound healing and an associated recovery of anterior corneal transparency and the restoration of epithelial innervation after epithelial trauma.
PURPOSE: To examine the role of Bowman's layer (BL) on the nature of anterior corneal regeneration after excimer laser phototherapeutic keratectomy (PTK). METHODS: A cohort of 13 patients underwent PTK to remove either 7 mum of BL for treatment of primary recurrent corneal erosions (RCE; six patients) or complete BL removal (15-mum ablation) to treat RCE or poor vision secondary to map-dot-fingerprint (MDF) dystrophy (seven patients). Clinical examinations and laser-scanning in vivo confocal microscopy (IVCM) were conducted before surgery and at a mean of 4 and 8 months after surgery. RESULTS: Total BL removal resulted in a significant decline in subbasal nerve density at 4 months (P = 0.007) that barely recovered to preoperative levels at 8 months (P = 0.055). With BL partially present, subbasal nerve density did not significantly change from preoperative levels. Superficial, wing, and basal epithelial cell density recovered to preoperative levels within 4 months after PTK, regardless of the presence of BL. Subepithelial keratocytes, however, were more densely distributed in corneas without BL relative to those with a partial BL present (P = 0.005), and increased anterior keratocyte reflectivity was noted in all eyes without BL and in no eye with a partial BL present. CONCLUSIONS: Subbasal nerve regeneration is delayed and subepithelial keratocyte density and reflectivity remain elevated up to 10 months after total BL removal by PTK. The results provide initial evidence for a possible role of BL in facilitating rapid stromal wound healing and an associated recovery of anterior corneal transparency and the restoration of epithelial innervation after epithelial trauma.
Authors: Sarag Abhari; Michael Eisenback; Henry J Kaplan; Eric Walters; Randall S Prather; Patrick A Scott Journal: Anat Rec (Hoboken) Date: 2018-10-05 Impact factor: 2.064
Authors: Holly Rose Chinnery; Rajni Rajan; Haihan Jiao; Mengliang Wu; Alexis Ceecee Zhang; Manikkuwadura Eranda Harshan De Silva; Eve Makrai; Mary Ann Stepp; Nick Di Girolamo; Laura Elizabeth Downie Journal: Br J Ophthalmol Date: 2021-02-10 Impact factor: 5.908
Authors: Anca Pantalon; Martin Pfister; Valentin Aranha Dos Santos; Sabina Sapeta; Angelika Unterhuber; Niklas Pircher; Gerald Schmidinger; Gerhard Garhöfer; Doreen Schmidl; Leopold Schmetterer; René M Werkmeister Journal: Acta Ophthalmol Date: 2019-02-14 Impact factor: 3.761