The shrinking eye: dimensional changes in the young child's eye after glaucoma drainage device implantation for refractory childhood glaucoma

Abstract

To investigate the magnitude of reduction in the axial length (AL) and corneal diameter following glaucoma drainage device (GDD) placement and intraocular pressure (IOP) reduction in glaucoma patients <3years of age at surgery. The medical records of consecutive childhood glaucoma patients who underwent GDD implantation at a single practice between 2013 and 2018 and were <3years of age at surgery were reviewed retrospectively. Demographics, glaucoma diagnoses, surgical details, and pre- and post-procedure measurements of AL, IOP, corneal diameter, central corneal thickness, presence of corneal edema, and cup:disk ratio were analyzed. A total of 16 eyes of 10 patients were included. Before GDD placement, mean AL was23.49±3.05mm. Mean AL reduction after placement was 0.80 ± 0.85mm(P=0.001); median AL reduction, 0.93mm (range, -3.05 to +0.59). Mean IOP reduction after GDD placement was 15.0±6.0mm Hg (P<0.0001). IOP reduction and AL reduction were significantly related (P=0.0013). Mean corneal diameter before GDD placement was 13.0±1.6mm; mean corneal diameter reduction after placement was 0.3±0.3mm(P=0.012). Reduction of corneal diameter and of AL were significantly related (P=0.03); corneal diameter and IOP were not (P=0.40). Objective cupping reversal after GDD was noted in 50% of eyes with documented cup:disk ratio. In this study cohort, reduction in AL, corneal diameter, and cup:disk ratio was found to be correlated with reduced IOP after GDD placement. This result merits consideration during surgical planning for glaucoma patients <3years of age.