This study was conducted to measure macular ganglion cell-inner plexiform layer (mGC-IPL) thickness in patients with a history of unilateral single attack of acute primary angle closure (APAC) and to compare it with that of unaffected fellow eyes 8 weeks after resolution using spectrum domain optical coherence tomography (SD-OCT).

Medical records of 24 patients with history of first episode of unilateral APAC were reviewed retrospectively. Eight weeks after APAC, mGC-IPL thickness and peripapillary retinal nerve fiber layer thickness were measured with SD-OCT and analyzed in eyes affected by APAC (group 1) and fellow eyes (group 2).

There were no significant differences between the groups with regard to best corrected visual acuity, spherical equivalent, central corneal thickness, or axial length ( p > 0.05). There were no significant differences in mGC-IPL thickness in the superotemporal, superior, or superonasal sectors ( p > 0.05). However, average, inferonasal, inferior, and inferotemporal sectors of group 1 were significantly thinner than those of group 2 ( p = 0.002, 0.002, 0.001, 0.001, respectively). In addition, average mGC-IPL difference between affected eyes and fellow eyes showed a statistically significant correlation with attack duration (correlation coefficient = 0.249, p = 0.019).

Normalization of elevated intraocular pressure as soon as possible after APAC onset is recommended in order to reduce mGC-IPL loss, and measurements of mGC-IPL thickness can be helpful for follow-up of APAC patients.