the occurrence of cupping of the optic disk , which is not present with purely vascular optic nerve diseases , and the location of visual field defects in low-tension glaucoma , which is similar to that in glaucoma simplex but different from vascular diseases , as well as the increased diurnal tension variations of diurnal tension curves compared to the normal population are all factors which indicate that low-tension glaucoma is not a purely vascular optic nerve disease , and that pressure-lowering therapy is necessary .
C0152136
low-tension glaucoma
C0029132
optic nerve disease