Single Block Conjunctival Limbal Autograft for Unilateral Total Limbal Stem Cell Deficiency

Dear Editor, In the treatment of unilateral total limbal stem cell deficiency (LSCD), conjunctival limbal autograft (CLAU) surgery taken from the healthy fellow eye with or without amniotic membrane transplantation (AMT) is one of the main therapeutic alternatives. There are some controversies regarding the optimal size of the limbal graft necessary for complete and stable epithelialization of the cornea. Traditionally, two 60° limbal grafts have been used. Few attempts have been made to reduce the overall size of the donor graft and it has been suggested that combining CLAU and AMT as a graft may minimize the required size of the limbal graft. In a single case report, a group of authors noted that corneal epithelialization using one 60° block of CLAU was complete by day 18 after surgery. They attributed this achievement to the use of amniotic membrane (AM) as a permanent graft underneath the CLAU and as a temporary patch over it. It has already been shown that in partial LSCD, one segment CLAU may suffice. Rao et al successfully used one 60‑90° limbal block for treating eyes with partial LSCD. They found it insufficient to treat 2 other eyes with total LSCD. Moldovan et al also found that one 90‑100° limbal block could restore eyes with total LSCD but that of 80° block surgery was unsuccessful. In the present study, patients with total unilateral LSCD received a single 60° limbal block of CLAU, and we observed that the procedure was insufficient for stable and permanent ocular surface epithelialization by corneal phenotype epithelium. Medical charts of patients, who had received a single Letter 60° block of CLAU or had inadvertently lost one of their blocks from previous conventional CLAU, were evaluated (March 2011 to April 2013). All patients suffered from total unilateral LSCD due to chemical injury with total conjunctivalized/vascularized corneal opacity and poor epithelial integrity (persistent or recurrent epithelial defects) experiencing chronic irritation, redness, tearing and decreased visual acuity. A fluorescein clearance test showed normal tear secretion and drainage. Diagnosis of total LSCD in all patients was based on characteristic clinical findings and confirmed by classic impression cytology. Integrity of the ocular surface epithelium was evaluated by fluorescein staining and the pattern of epithelial healing was evaluated. Findings were documented using digital corneal photography (Imagenet; Topcon SL‑8Z, Tokyo, Japan) at all follow‑up visits. All risks and benefits were clearly explained, and informed consent was obtained from all …