Abstract
Purpose:
To evaluate the association of peripapillary, macular choroidal thickness(CT) and progression of visual field damage in normal-tension glaucoma(NTG)
Methods:
A 360-degree peripapillary circle scan was performed using the standard protocol for retinal nerve fiber layer (RNFL) assessment and macular choroid was measured using enhanced depth imaging optical coherence tomography. Using provided software, two independent masked investigators manually segmented CT to delineate the posterior edge of the retinal pigment epithelium and the sclerochoroidal interface. Independent t-test was used determine differences in RNFL and CT at all location in peripapillary and macula between visual field progressing group and visual field non-progressing group. The associations of choroidal thickness with independent parameters including the presence of progression, age, sex, refractive error, axial length, central corneal thickness, visual field mean deviation, visual field pattern standard deviation were assessed with mixed model univariate and multivariate analyses.
Results:
Among the 100 eyes of 100 patients, 23 eyes were classified into progressing group and 77 eyes were classified into non-progressing group. The global peripapillary and subfoveal choroidal thickness measurements were 151.12 ±48.10 µm and 248.13 ± 69.47 µm in non-progressing group, 155.52 ± 47.64 µm and 262.24 ± 69.27 µm in progressing group(p=0.700, p=0.395). The RNFL thickness and CT at all peripapillary locations and macular area did not differ between the group(all P>0.1). Age (p= 0.004) and axial length (P<0.0001) were negatively associated with peripapillary CT. The presence of visual field progression and the degree of glaucoma severity were not statistically significantly associated with peripapillary CT.
Conclusions:
There was no significant difference in peripapillary and macular CT of NTG eyes with visual field progression compared with no visual field progression which does support that CT may not play a role in pathogenesis of NTG even with the visual field progression in NTG.