Anterior Chamber Angle Evaluation with Spectral-Domain Optical Coherence Tomography in preterm patients with and without retinopathy of prematurity

Abstract

Purpose: To describe optical coherence tomography (OCT) findings of the anterior chamber angle in preterm infants with less than 37 weeks gestational age.

Methods: Retrospective case series of premature infants who underwent imaging of the anterior chamber angle under topical anesthesia with Handheld iVUE OCT device (OptoVue, Fremont, CA).

Results: We included 37 eyes of 21 premature infants with mean gestational age 30.41 ± 2.42 weeks (27-33) with mean birthweight 1339 ± 365.26 gr (898-2500). By the time of examination mean age was 14.09 ± 13.85 (1-35) weeks corrected gestational age, average oxigen therapy was 34.55 ± 20.67 days (10-60). Amongst our sample, there were 8 patients with retinopathy of prematurity (ROP) stage 1 zone II (1 patient), stage 1 zone II (2 patients), stage 1 zone 1 with plus disease (1 patient), stage 2 zone II (2 patients), stage 3 zone II (1 patient), stage 5 (1 patient). We measured the anterior chamber angle in 11 eyes with a mean opening of 28.54 degrees ± 10.97 (15.29-44.16). Trabecular-iris space area distances at 500μ from scleral spur (TISA500) were measured in 13 eyes wih a mean of 0.179 mm2 ± 0.077 (0.093-0.327). Twenty six eyes were not analyzed due to inability to identify the scleral spur (15 eyes) angle vertex (2 eyes) and/or an oblique measurement in relation to the limbus (14).

Conclusions: Using OCT we were able to measure the anterior chamber angle and TISA500 of premature infants. We found that the visualization of the scleral spur was challenging with this method. Despite the difficulty in the obtention of high-quality images, OCT is a useful tool for evaluation and measurements of some the anterior chamber angle structures. Obtaining these images helps our understanding of the mechanisms of development of ocular structures in vivo and may be used in the future for additional evaluation in paediatric population.

Keywords: 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • 706 retinopathy of prematurity • 420 anterior chamber