Abstract
Purpose: :
To evaluate the clinical characteristics of normal tension glaucoma(NTG) in young patients.
Methods: :
Under age 40 of 50 eyes of patients with NTG and 44 eyes of normal subjects underwent complete ophthalmic exam including the assessment of visual acuity, spherical equivalents(SE), intraocular pressure, axial length(AXL), central corneal thickness(CCT), peripapillary retinal nerve fiber layer(RNFL) thickness. Disc characteristics(Disc size, vertical cup-disc ratio, disc ovality, presence of zone ß peripapillary atrophy(PPA)) were morphometrically examined on stereoscopic fundus photograph using an image analyzer(Image J). We compared clinical characteristics of morphologic, functional ocular parameters between the group and association of these parameters with NTG and normal group was analyzed by logistic regression analysis.
Results: :
The mean SE and AXL were significantly different between normal group and the NTG group(p<0.001, p<0.001). The frequency of oval optic disc, zone ß PPA were significantly higher in NTG group than normal group(p=0.042, p<0.001). Optic disc size and CCT were no statistically different between the group(p=0.057, p=0.542). High myopia or Long axial length was significantly associated with NTG. (Odd ratio 0.732, 95% CI 0.565, 0.949, P=0.007, Odd ratio 1.691, 95% CI 1.050, 2.724, P=0.031).
Conclusions: :
The frequency of Myopia, zone ß PPA and oval disc were significantly higher in NTG group. Long axial lengths or high myopia can be considered as s risk factor for NTG in young patients.