Ocular Surface O C T Imaging In Pterygium

Pterygia are fibrovascular degenerations of the conjunctiva that advance across the cornea over time. Pterygia are usually located in the interpalpebral zone, more often nasal than temporal. Symptoms of pterygia include redness, irritation, dryness, tearing, and decreased vision. Decreased vision typically results from: (1) involvement of the visual axis, (2) induced astigmatism, and (3) tear film disruption. The purpose of the study is to examine the alterations of the corneal surface beyond the the visible limits of pterygium in pterygium case that do not involve or threaten the visual axis

Department of Ophthalmology, General Hospital of Lamia, Lamia, Greece

Pilot study of 9 patients (9 eyes) with pterygium encroaching onto the surface of the cornea. No case involved the visual axis and they were out of the limits of photopic pupil. Data concerning Visual Acuity, Keratometric reading, Anterior Segment photography and Anterior Segment OCT  were collected as well as relevant postoperative data. All patients underwent pterygium surgery with conjuctival autograft. Postoperative data were collected one month after pterygium surgery.

Anterior Segrment OCT depicted severe abnormalities of the central cornea, not involving the visual axis but extending well beyond the visible limits of pterygium.  In all cases visual acuity was affected and keratometry readings revealed much higher degree of astigmatism than the clinical refraction. Perygium surgery was more wide than visible limits of pterygium to include these abnormalities. Postoperatively visual acuity returned to normal and keratometry reading as well as anterior segment OCT normalized significantly.

Anterior segment OCT reveals the significance of pterygium induced astigmatism and helps in guiding the extend of pterygium surgical excision in order to restore patient's vision.