Investigation of retinal nerve fiber layer thickness and ganglion cell layer-inner plexiform layer thickness in patients with optic pathway gliomas.

ABSTRACT

PURPOSE: This study aimed to compare the optical coherence tomography (OCT) findings of optic pathway glioma (OPG) patients (sporadic or secondary to neurofibromatosis type 1, NF1) with NF1 without OPG patients and healthy controls. METHODS: This was a prospective, case-control study in which 27 patients (13 with OPGs and 14 with NF1 without OPGs) and 13 control subjects were included. The retinal nerve fiber layer (RNFL) thickness, macular thickness, and ganglion cell layer-inner plexiform layer (GCL-IPL) thickness findings measured using OCT and the results were compared between the groups. RESULTS: The macular thickness was significantly lower in the OPG group than in the control group and the NF1 patients without OPGs group (p < 0.001). The GCL-IPL thickness was lower in OPG group than in the control group and the NF1 patients without OPG group (p < 0.001). The RNFL thickness was lower in the OPG group than in the control group and the NF1 patients without OPG group (p < 0.001). There was a statistically significantly negative correlation between the visual acuity (log of the minimum angle of resolution, logMAR) and all the other parameters (macular, RNFL, and GCL-IPL thicknesses). All the parameters were found to positively correlate with each other. CONCLUSIONS: OCT measurements (macular thickness, RNFL, and GCL-IPL thicknesses) can be used to monitor the disease in those patients with suspected OPGs; however, this should be verified with a larger case series.