This prospective randomized study compared recurrence rates after pterygium surgery using free conjunctival autograft (CAU) or conjunctival-limbal autograft (CLAU), both combined with adjunctive mitomycin C. The authors found no significant difference in pterygium recurrence rates between the groups among primary or recurrent cases. However, they note that limbal damage was seen in some eyes with CLAU, and the procedure is more time consuming and requires greater surgical expertise.
The study included 78 patients with primary or recurrent nasal pterygia randomized to pterygium surgery using CAU or CLAU with application of 0.02% mitomycin C for three minutes.
After surgery, no eye in the CLAU group developed pterygium recurrence. However, recurrence was seen in two eyes (5.1 percent) in the CAU group, including 1 of 31 patients (3.2 percent) with primary pterygia and 1 of 8 patients (12.5 percent) with recurrent pterygia. In the CLAU group, a localized pannus formation at the donor site of the limbal graft was noted in five eyes (12.8 percent), with the appearance of pseudopterygium in one eye.
The authors say the additive effect of mitomycin C, which has been shown to reduce pterygium recurrence, is one of the reasons for the low recurrence rates in both treatment groups. Since the recurrence rates were similar, even in recurrent cases, it seems that with mitomycin C application, there is no additional benefit in transplanting limbal graft for pterygium surgery.
Also they note that conjunctival inflammation was observed at one month after surgery in 15 eyes (19.2 percent), with similar rates in the CAU and CLAU groups. Eleven eyes with moderate inflammation were treated with subconjunctival injection of triamcinolone, which resolved the inflammation. They say this treatment may have played a role in the study's low recurrence rates.
I believe that the relatively frequent occurrence of granuloma formation at the donor site and postoperative inflammation around the graft seen in this study may have been related to the adjunct use of mitomycin C and might have been avoided if a corticosteroid ointment had been used during the first postoperative week and later replaced by eye drops. Since no benefit of either graft was demonstrated, a conjunctival autograft without mitomycin C is a reasonable choice because it does not affect the limbal cells and is faster to perform.