Anterior chamber angle features in primary congenital glaucoma infants using hand-held anterior segment-oct

Purpose To describe anterior chamber angle (ACA) structures and parameters in primary congenital glaucoma (PCG) and normal infant eyes, using Hand-held anterior segment optical coherence tomography (HH AS-OCT), as an in-office, non-contact technique. Methods Normal and PCG-infants <24 months were examined, using HH AS-OCT (RTVue RT- 100, Optovue Inc., Fremont, CA). Sedation was not required. Corneal pachymetry map, ACA width and iris thickness (IT) were measured. Trabecular meshwork (TM), Schlemm's canal (SC), and scleral spur (SS) identification were assessed in both groups. Results Forty-eight infants; (26 PCG-eyes and 22 normal-eyes) aged 9.12 +/- 6.7 months, were included. Nasal and temporal ACA width in PCG infants was found significantly larger (39.3 +/- 6.6 degrees vs. 30.4 +/- 5.6, and 40.1 +/- 5.3 degrees vs. 32.5 +/- 6.2 respectively) (p < 0.001). IT was significantly reduced (121.7 +/- 43.9 mu m in PCG-infants, vs. 160.3 +/- 38.6 mu m in normal-eyes) (p < 0.01). TM was identified in all normal eyes (100%) and nine (34.6%) PCG- eyes. SC was identified in 16 (72.7%) normal eyes versus four (15.4%) PCG. In PCG-eyes, an abnormal structure occluding the angle was seen in seven (26.9%), and a hyper-reflective membrane in five (19.2%), the iris was anteriorly inserted in all PCG-eyes, and iridotrabeculodysgenesis was clearly identified (with constant iris anterior insertion). The abnormal tissue obscuring the angle was seen in younger PCG-infants and iris thinning appeared to be part of the pathology, not a result of IOP elevation. Conclusion Using HH AS-OCT permits tomographic examination of the ACA in PCG infants and may help in the understanding of disease pathology. Hence, may assist in optimizing treatment.

Automated summary

The study used HH AS-OCT to examine ACA structures and parameters in PCG and normal infant eyes, finding that PCG infants had larger ACA width, reduced IT, and lower identification rates of TM and SC. Abnormal structures, anterior iris insertion, and iridotrabeculodysgenesis were observed in PCG eyes.