Abstract
Purpose :
To report outcomes of manual deep anterior lamellar keratoplasty (DALK) performed in pediatric patients diagnosed with mucopolysaccharidoses (MPS).
Methods :
The electronic medical records of all children diagnosed with MPS who underwent manual DALK surgery between 2009 and 2022 at The Hospital for Sick Children were reviewed retrospectively. Data collected included demographic information, ocular comorbidities, postoperative vision, clarity of the graft and host rim, and complications.
Results :
Twenty-nine eyes of 18 patients were identified, including 8 (44%) females. Nineteen eyes (65.5%) were from patients who had undergone bone marrow transplant (BMT) and the remaining 10 (34.5%) were on enzyme replacement therapy. Average age at surgery was 11.9+4.3 years. The mean follow-up was 4.5+3.5 years. No cases required conversion to penetrating keratoplasty. One eye required repeat graft due to graft rejection from early and abrupt discontinuation of postoperative steroids. Three eyes developed possible rejection episodes which subsequently resolved with topical steroids. In the remaining cases, topical steroids were tapered and discontinued on average by 1.09+0.78 years postoperatively. In 26 eyes (93%), clearing of the host rim was documented by postoperative year one and persisted in follow-up. No eyes demonstrated recurrence of opacification at final follow-up. Improvement in vision was noted in 63.2% of eyes at 1 year (mean of -0.1+0.4 logMAR) and in 73.3% (-0.2+0.4 logMAR) at final follow-up. A decrease in intraocular pressure (IOP) by a mean of 10.3+6.0 mmHg was observed by 6 months postoperatively and this change was sustained.
Conclusions :
Manual DALK for MPS has excellent graft survival in long-term follow-up with a low risk of rejection following cessation of topical steroid at postoperative years 1-2. To our knowledge, this is the largest case series of patients with mucopolysaccharidoses undergoing DALK by any method. Importantly, postoperative clearing of the host rim was observed as a sustained change over time across the MPS subtypes, potentially due to keratocyte migration from the donor cornea. Vision improved in the majority of patients post-DALK though underlying amblyopia was a limiting factor. A substantial decrease in IOP postoperatively was speculated to relate to increased corneal rigidity in pre-operative corneas with glycosaminoglycan deposition and associated collagen fibril disorganization.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.