Excimer laser in the treatment of recurrent pterygia

Authors report two cases of multiple recurrent pterygia which were treated with the usual surgical technique (sec. Arlt) and a subsequent excimer laser treatment. In case one they used slit mode, in the other case spot mode was applied. The superficial phototherapeutic ablations were performed with an Aesculap Meditec MEL 60 193-nm Arf excimer laser. During a one year follow-up period recurrence was experienced in both cases. According to the literature in primary pterygia the excimer laser might be helpful in the reepithelization by smoothing the corneoscleral surface. In recurrent cases, however, the glycosaminoglycane content of the collagen fibres are lower in the corneal scar tissue, so due to the impaired hydratation, the fluency of the excimer laser might fail to ablate the pathological surface structures. On the other hand, in recurrent cases the corneoscleral barrier function is also heavily impaired, so the conjunctival epithelial cells are not able anymore to recognize the corneoscleral border. It is concluded that in recurrent cases the excimer laser phototherapeutic treatment is of less value than in primary pterygia.