AUG 06, 2012
The authors of this study reviewed their surgical outcomes treating multicurrent pyterygia over an eight-year period using a new grading system and by sealing the gap between the conjunctiva and Tenon capsule. They conclude that caruncle morphological characteristics and residual conjunctiva measurement help grade the severity of recurrent pytergia, guide surgical techniques and predict outcomes. Sealing of the gap is important to create a strong barrier for preventing recurrence, restoring caruncle morphological characteristics and regaining full motility in multirecurrent pterygia.
The study included 30 patients (32 eyes) with pterygia managed at the Ocular Surface Center in Miami from 2002 through 2010. They were consecutively operated on by recession; sealing of the gap; covering of exposed medial rectus muscle by amniotic membrane, conjunctival autograft or oral mucosal graft; and covering of the bare sclera with amniotic membrane.
The authors found that the grading system they used was clinically useful for primary pterygia but not suitable for recurrent pterygia because episcleral vessels were not visible in most of the eyes. However, caruncle grading strongly correlated with residual conjunctiva (P = 0.01), severity of diplopia (P = 0.001) and overall success rate (P = 0.05). Amniotic membrane transplantation alone was successful in 23 eyes with residual conjunctiva of a mean of 27.8 mm. This was significantly longer than those in six cases in which amniotic membrane transplantation failed (13.1 mm, P = 0.007) and eight cases in which amniotic membrane transplantation was successful but required an additional conjunctival autograft or oral mucosal graft (10.9 mm, P = 0.001).
During a mean (SD) follow-up of 27.5 (20.5) months, 30 eyes (94 percent) achieved total success without recurrence and diplopia. Normal caruncle was obtained in 17 of 21 eyes (81 percent) with abnormal caruncle before surgery. One eye developed corneal recurrence and was lost to follow-up, and one eye was left with a depressed caruncle and residual diplopia on adduction.
The authors say their findings highlight the importance of the fibrovascular tissue emanating from the caruncle in contributing to pterygium growth and demonstrate the effectiveness of sealing the gap in combating pterygial recurrences. They speculate that failure in sealing such a gap explains the highly variable recurrence rates reported with different surgical approaches.