Purpose: To compare the relationship between macular ganglion cell layer
(mGCL) thickness and 10-2 visual field (VF) sensitivity using different
stimulus sizes in patients with temporal hemianopia from chiasmal
compression. Methods: A cross-sectional study was conducted involving 30
eyes from 25 patients with temporal VF loss on 24-2 SITA standard
automated perimetry due to previous chiasmal compression and 30 healthy
eyes (23 controls). Optical coherence tomography (OCT) of the macular area
and 10-2 VF testing using Goldmann stimulus size I (GI), II (GII), and III
(GIII) were performed in the Octopus 900 perimeter. For the sake of
analysis, mGCL thickness and VF data were segregated into four quadrants
(two temporal and two nasal) and two halves (temporal and nasal) centered
on the fovea, and the groups were compared using generalized estimated
equations. The discrimination ability of GI, GII, and GIII was evaluated,
as was the correlation between mGCL and 10-2 VF sensitivity using GI, GII,
and GIII. Results: All mGCL parameters were significantly reduced in
patients compared to controls. 10-2 VF test sensitivity using GI, GII, and
GIII was significantly lower in patients than in controls (p≤0.008) for
all parameters, except the three nasal divisions when using GI (p=0.41,
0.07 and 0.18) Significant correlations were found between temporal VF
sectors (all stimulus sizes) and the corresponding nasal mGCL
measurements, with similar discrimination ability. Significant
correlations were also observed between all three nasal VF divisions and
the corresponding temporal mGCL thickness when using stimulus sizes I and
II, but not stimulus size III. Conclusions: On 10-2 VF testing, GII
outperformed GI and GIII with regard to discrimination ability and
structure-function correlation with mGCL thickness in chiasmal
compression. Our findings suggest that the use of GII can enhance the
diagnostic power of 10-2 VF testing, although further studies are
necessary to support this conclusion.