Argon Laser Peripheral Iridoplasty for Primary Angle Closure Glaucoma
Status:
Unknown status
Trial end date:
1969-12-31
Target enrollment:
Participant gender:
Summary
Glaucoma is the leading cause of irreversible blindness worldwide. With ageing of the
population, glaucoma morbidity will rise, causing increased health care costs and economic
burden for a condition in which visual loss, once established, cannot be reversed. In
contrast to western countries, primary angle closure glaucoma (PACG) is a major form of
glaucoma in Asia. In a recent population based survey in Singapore, the prevalence of
glaucoma was 3.2% in the Chinese population over 40. Glaucoma was the leading cause of
blindness, with PACG the most visually destructive form of the disease.
Laser iridotomy is the current first line treatment for PACG. It acts by relieving pupil
block, which in turn may reduce intraocular pressure (IOP) and prevent progression of
glaucoma. However recent data indicate that iridotomy is not successful in controlling IOP in
the long term, and the majority of cases develop a clinically significant rise in IOP
requiring medical therapy or surgery.
Argon laser peripheral iridoplasty (ALPI) offers a new therapeutic option for PACG. The
procedure consists of placing contraction burns in the iris periphery which results in
contraction of the iris stroma and opening of the angle.
The proposed study is a 2-centre randomized controlled trial to determine whether ALPI is an
effective and safe treatment in the management of PACG. 210 patients with PACG and high IOP
(>21 mmHg) following laser iridotomy will be randomized to receive ALPI or medical treatment
to achieve IOP control. Subjects will be followed up for 12 months and the outcome criteria
will be the rate of medical treatment and surgery in each group, and the angle width and
configuration.
This will be the first RCT worldwide to address the role of ALPI in PACG. The study findings
will have great relevance for the prevention of glaucoma blindness in the elderly.