The effect of pilocarpine on the glaucomatous visual field.
Patients with chronic open angle glaucoma are traditionally managed by medical therapy during the early stages of the disease. Pilocarpine is a well established topical agent, but suffers troublesome sequelae, the most apparent of which is pupillary constriction. This study assesses the effect of miosis (produced by one drop of 2% pilocarpine) on the static threshold perimetry of 20 subjects with chronic open angle glaucoma and documented visual field loss, using the 30-2 program of the Humphrey field analyser. Following miosis, the Statpac mean defect deteriorated by an average of -1.49 dB compared with baseline (p = 0.004). This dB deterioration is twice that reported in studies on younger normal subjects following miosis. The decrease in mean defect showed a positive correlation with the degree of pupillary constriction, the correlation being greater in those eyes with a miosed pupil diameter of 2 mm or less. There was no significant decrease in the other Statpac global indices following miosis. A parallel study using the fellow eye of the same glaucoma patients showed a high degree of intertest variability, but no significant learning or fatigue effect. We conclude that pilocarpine-induced miosis causes a significant deterioration in visual field in a population of patients with chronic open angle glaucoma: this factor should be considered when choosing therapy for glaucoma particularly in cases where field loss approaches the permitted legal minimum for driving.
Webster
A R
AR
Southampton Eye Hospital.
Luff
A J
AJ
Canning
C R
CR
Elkington
A R
AR
D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D005260:Female; D005902:Glaucoma, Open-Angle / Q000188:drug therapy* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015877:Miosis / Q000139:chemically induced / Q000503:physiopathology; D010862:Pilocarpine / Q000009:adverse effects / Q000627:therapeutic use*; D011680:Pupil / Q000187:drug effects / Q000502:physiology; D014794:Visual Fields / Q000187:drug effects*
D010862:Pilocarpine