Abstract
Purpose :
Patients with chiasmal compression from pituitary tumors have retinal nerve fiber layer and ganglion cell layer thinning that are correlated with visual field (VF) defects. Few studies have evaluated the outer retinal layers in these patients, with contradicting conclusions. The purpose of this study is to investigate outer retinal parameters in patients with pituitary tumors and VF loss.
Methods :
In this retrospective cross-sectional study, 19 eyes of 10 patients with temporal hemianopia due to pituitary tumors and 17 healthy control eyes were included for analysis. All patients underwent VF and spectral-domain OCT testing prior to resection of the tumor. OCT scans were segmented using a machine learning-enabled platform with manual correction. Output metrics included thickness of the inner retina (internal limiting membrane to outer plexiform layer), middle retina (outer nuclear layer [ONL] to ellipsoid zone), outer retina (ONL to retinal pigment epithelium), and photoreceptor outer segment (OS). These layers were further segmented into nasal and temporal hemiretinas.
Results :
The inner retinal volume (p=0.007) was statistically significantly smaller in patient eyes compared to control eyes. There was no significant difference between the middle retina (p=0.068) or outer retina (p=0.184) thickness of the 2 groups; however, when isolating the nasal retina, the patient group had a significantly thinner nasal middle retina (p=0.003) and nasal outer retina (p=0.007) compared to the control group. The difference between the mean thickness of the 2 groups was 15.54µm in the nasal middle retina compared to 0.10µm in the temporal middle retina, and this difference was 15.43µm in the nasal outer retina compared to 0.31µm in the temporal outer retina. There was no significant difference in the OS thickness or nasal OS thickness between the two groups.
Conclusions :
This is the first study to demonstrate thinning of the nasal outer retina in patients with temporal hemianopia from chiasmal compression. Longitudinal analysis and correlation with other clinical and testing parameters are needed to evaluate the significance of these findings.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.