Investigating visual field measurements on perimetry and ganglion cell complex on optical coherence tomography in patients with suprasellar tumours.

BACKGROUND: Suprasellar tumours can cause compressive optic neuropathy with preventable visual loss. Standard automated perimetry is central to assessment but is subjective; optical coherence tomography (OCT) provides ganglion cell complex (GCC) metrics, yet structure-function relationships in chiasmal compression remain unclear. This study evaluated the relationship between GCC thickness and visual field (VF) loss (10-2 and 30-2). METHODS: Prospective observational study of patients with suprasellar tumours undergoing OCT GCC imaging and Humphrey VF testing (10-2 and 30-2). Ganglion cell complex abnormality was defined as a machine-flagged red value. Visual field abnormality was defined on the pattern deviation (PD) map as a scotoma (≥ 3 adjacent points with p < 5%). Associations between GCC thickness and VF PD were assessed, and agreement between binary classifications was evaluated. RESULTS: Seventeen eyes were included (mean age 50.7 years; 70.0% female). Visual field abnormality was frequent (10-2: 82.4%; 30-2: 94.1%), while GCC was abnormal in 58.8%. Mean PD was -6.84 dB (10-2) and -8.66 dB (30-2). Ganglion cell complex thickness correlated with PD at 10-2 (p < 0.001) and 30-2 (p = 0.001). Agreement was moderate for GCC versus VF 10-2 (κ = 0.469) and slight for GCC versus VF 30-2 (κ = 0.164). CONCLUSION: Visual field abnormalities were common, with 30-2 classifying more eyes as abnormal despite normal GCC. Ganglion cell complex thickness showed a graded association with VF loss on both strategies, supporting OCT GCC as an adjunct for quantifying chiasmal compression-related dysfunction; however, binary OCT classification may miss milder functional deficits. CONTRIBUTION: Supports combined OCT-perimetry interpretation and strategy-aware follow-up.