The Ability of 10-2 Short-Wavelength Perimetry in Detecting Functional Loss of the Macular Area in Preperimetric Glaucoma Patients.

PURPOSE

To better understand functional loss in the macular area of preperimetric glaucoma patients exhibiting structural loss by exploring correlations between parameters of the ganglion cell-inner plexiform layer (GCIPL) and 10-2 short-wavelength perimetry (SWAP).

METHODS

One hundred thirty-four patients underwent 10-2 SWAP and conventional 24-2 visual field (VF) testing using a Humphrey field analyzer and macular scanning via Cirrus optical coherence tomography (OCT). Correlations between GCIPL thickness (GCIPLT) and the mean sensitivity (MS) of topographically corresponding areas explored in various VF tests were calculated. Correlations between GCIPL parameters and MS of the VF, in terms of the asymmetries of various VF sectors, were also determined.

RESULTS

Glaucoma patients, preperimetric by standard 24-2 VF analysis but exhibiting GCIPL thinning, had lower MS in 10-2 SWAP and central 24-2 VF analyses. The correlations between average GCIPLT and the corresponding MS were significant for both 10-2 SWAP (r = 0.291, P = 0.018) and 24-2 standard automated perimetry (r = 0.235, P = 0.029). The associations between sectoral GCIPLT and the corresponding 10-2 SWAP MS were significant for all sectors, with the highest correlation evident in the inferotemporal (r = 0.324, P = 0.009) and the lowest in the superonasal GCIPL sectors (r = 0.214, P = 0.043). Asymmetric relationships between GCIPLT and 10-2 SWAP MS exhibited similar yet stronger correlations.

CONCLUSIONS

Preperimetric glaucoma patients exhibiting structural loss in the macula also had functional loss revealed by 10-2 SWAP, which was less prominent in conventional 24-2 VF. Therefore, if structural abnormality is evident in the macular area, the central VF areas should be further examined even if the standard 24-2 data appear to be normal.