Aqueous flow in open-angle glaucoma
L. I. Larsson, E. S. Rettig and R. F. Brubaker
Department of Ophthalmology, Mayo Clinic.
OBJECTIVES: To measure aqueous dynamic variables in patients with
open-angle glaucoma when their ocular hypotensive treatment was withdrawn
and to determine if the circadian rhythm of the aqueous humor flow was
present in open-angle glaucoma. METHODS: We studied 20 patients with
open-angle glaucoma, and a group of 20 healthy subjects served as controls.
Aqueous humor flow was measured by clearance of topically applied
fluorescein with a fluorophotometer, tonography was used to measure outflow
facility, and applanation tonometry was used to measure the intraocular
pressure. RESULTS: We did not find any statistically significant difference
when comparing aqueous flow during the daytime in subjects with open-angle
glaucoma with that in controls. However, we did measure a higher aqueous
flow at night in the group with open-angle glaucoma, compared with the
normal group. The circadian rhythm of aqueous humor flow was present in the
subjects with glaucoma. CONCLUSIONS: Aqueous flow is not suppressed in
glaucomatous eyes that are not undergoing treatment. Rather, the flow is
slightly higher at night during sleep compared with the flow in normal
sleeping subjects, but not high enough to have a clinically significant
effect on intraocular pressure.
