Table 1. Comparison of clinical characteristics of normal-tension glaucoma patients with initial central or peripheral visual field defects.

Characteristics (mean±SD)	Initial central scotomas (N=32)	Initial peripheral scotomas (N=34)	P-value
Follow-up period (yr)	7.19±2.53	7.47±2.06	0.626a
Demographic factors
Age(yrs)	49.87±11.60	48.50±14.76	0.677a
Gender, female	18 (56.3%)	19 (55.8%)	0.976b
Family history of glaucoma	2 (6.3%)	3 (8.8%)	1.000c
Systemic factors
Diabetes mellitus	3	3	1.000c
Hypertension	4	6	0.734b
Migraine	4	3	0.705c
Orthostatic hypotension	4	5	1.000c
Peripheral vascular disease	2	0	0.231c
Ocular factors
Spherical equivalent(D)	−1.79±1.78	−1.68±2.37	0.834a
CCT(um)	526.26±32.96	529.83±38.28	0.697a
Disc hemorrhage	6 (18.8%)	7 (20.6%)	0.851b
β-zone PPA	27 (84.4%)	31 (91.2%)	0.469c
Baseline IOP	17.03±3.21	17.62±2.87	0.436a
Post-therapeutic mean IOP	14.85±2.04	15.21±2.15	0.495a

Abbreviations: CCT, central corneal thickness; D, diopters; IOP, intraocular pressure; m, month; PPA, peripapillary atrophy; SD, standard deviation; VF, visual field; yr, year.

^aIndependent t-test.

^bχ²-test.

^cFisher exact test.