Abstract
Purpose: :
To evaluate and compare visual field defect (VFD) and optic disc morphology in n-AION and NTG eyes with nocturnal hypotension (nocturnal blood pressure dip>10% of mean daytime blood pressure)
Methods: :
Fifty-one eyes of 51 patients with n-AION and 51 eyes with NTG with nocturnal hypotension whose age, sex, and VFD were matched to those of the n-AION were recruited in a consecutive manner from May 2010 to August 2011. Pattern and location of VFD using Humphrey field analyzer (HFA) were compared between the two groups. Optic disc morphological features and peripapillary RNFL thickness using the spectral-domain optical coherence tomography (SD-OCT) were measured and compared between n-AION and NTG group with nocturnal hypotension.
Results: :
There was no significant difference in the disc area between the n-AION and the NTG eyes with nocturnal hypotension. The average cup-to-disc (C/D) area ratio, vertical C/D ratio, and cup volume were significantly smaller in the n-AION eyes than in the NTG eyes (P<0.001), whereas rim area was significantly greater (P<0.001). Inferior arcuate defect was most common (35%) in the n-AION group, whereas superior arcuate defect was in the NTG group (59%). Both groups resulted in high prevalence of parafoveal VFD (63% vs. 71%, P>0.05).
Conclusions: :
Disc topography of eyes with n-AION was quantitatively characterized by smaller cupping and a relatively larger rim area compared to eyes with NTG with nocturnal hypotension matched for age, disc size, sex, and VFD. In both groups, parafoveal VFD.
Keywords: optic disc • ischemia • visual fields