Argon laser peripheral iridoplasty versus conventional systemic medical therapy in treatment of acute primary angle-closure glaucoma : a prospective, randomized, controlled trial.
OBJECTIVE
To study whether argon laser peripheral iridoplasty (ALPI) is as effective and safe as conventional systemic medications in treatment of acute primary angle-closure glaucoma (PACG) when immediate laser peripheral iridotomy is neither possible nor safe.


METHODS
Prospective, randomized, controlled trial.


METHODS
Seventy-three eyes of 64 consecutive patients with their first presentation of acute PACG, with intraocular pressure (IOP) levels of 40 mmHg or more, were recruited into the study.


METHODS
The acute PACG eye of each consenting patient received topical pilocarpine (4%) and topical timolol (0.5%). The patients were then randomized into one of two treatment groups. The ALPI group received immediate ALPI under topical anesthesia. The medical treatment group was given 500 mg of intravenous acetazolamide, followed by oral acetazolamide 250 mg four times daily, and an oral potassium supplement until IOP levels normalized. Intravenous mannitol also was administered to the latter group if the presenting IOP was higher than 60 mmHg. The acute PACG eye of both groups continued to receive topical pilocarpine (1%) until peripheral iridotomy could be performed.


METHODS
Intraocular pressure profile, corneal clarity, symptoms, visual acuity, angle status by indentation gonioscopy, and complications of treatment.


RESULTS
Thirty-three acute PACG eyes of 32 patients were randomized to receive immediate ALPI, whereas 40 acute PACG eyes of 32 patients had conventional systemic medical therapy. Both treatment groups were matched for age, duration of attack, and IOP at presentation. The ALPI-treated group had lower IOP levels than the medically treated group at 15 minutes, 30 minutes, and 1 hour after the start of treatment. The differences were statistically significant. The difference in IOP levels became statistically insignificant from 2 hours onward. The duration of attack did not affect the efficacy of ALPI in reducing IOP in acute PACG. No serious laser complications occurred, at least in the early postlaser period.


CONCLUSIONS
Argon laser peripheral iridoplasty significantly is more effective than conventional systemic medications in reducing IOP levels in acute PACG in eyes not suitable for immediate laser peripheral iridotomy within the first 2 hours from the initiation of treatment. Argon laser peripheral iridoplasty is a safe and more effective alternative to conventional systemic medications in the management of acute PACG not amenable to immediate laser peripheral iridotomy.
Lam
Dennis S C
DS
Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong Eye Hospital, Kowloon, Hong Kong, People's Republic of China. dennislam@cuhk.edu.hk
Lai
Jimmy S M
JS
Tham
Clement C Y
CC
Chua
John K H
JK
Poon
Agnes S Y
AS
D000086:Acetazolamide / Q000627:therapeutic use*; D000208:Acute Disease; D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000627:therapeutic use; D002257:Carbonic Anhydrase Inhibitors / Q000627:therapeutic use*; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000188:drug therapy* / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007262:Infusions, Intravenous; D007429:Intraocular Pressure / Q000187:drug effects / Q000502:physiology; D007498:Iris / Q000601:surgery*; D053685:Laser Therapy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012449:Safety; D016896:Treatment Outcome; D014792:Visual Acuity
D000959:Antihypertensive Agents; D002257:Carbonic Anhydrase Inhibitors; D000086:Acetazolamide