Purpose: To study the long-term clinical course of patients with primary angle-closure glaucoma (PACG).
Design: Retrospective, noncomparative, interventional case series.
Participants: Sixty-five consecutive patients who were diagnosed with PACG at one Singapore hospital from January 1990 through December 1994.
Methods: Primary angle-closure glaucoma was defined as the presence of glaucomatous optic neuropathy and compatible visual field loss associated with a closed angle in the same eye. All study eyes underwent laser peripheral iridotomy (LPI). There were two groups of patients studied. Group A consisted of those with a past documented history of an episode of acute angle closure (that had resolved after LPI). Group B consisted of those with no previous acute episode. The presenting features, management, and subsequent long-term intraocular pressure (IOP) outcome were analyzed.
Main outcome measures: Intraocular pressure and the need for further glaucoma treatment.
Results: The follow-up period was 63 +/- 29 months (mean +/- standard deviation). The mean presenting IOP was 40 +/- 16 mmHg, and the presenting vertical cup-to-disc ratio was 0.6 +/- 0.2. Of the 83 eyes, only five eyes (6%) did not require any treatment after LPI in the long term. In group A (35 eyes), all eyes required further treatment with antiglaucoma medications. Twenty-two eyes (62. 9%) eventually underwent filtering surgery at a mean of 7.3 months after the commencement of treatment. In group B (48 eyes), 43 eyes (89.6%) underwent further medical therapy, of which 22 eyes (45.8%) eventually underwent filtering surgery at a mean of 18.4 months after the commencement of treatment.
Conclusions: Despite the presence of a patent LPI, most eyes with established PACG require further treatment to control IOP. Medical therapy fails in most cases, necessitating filtering surgery. Patients risk experiencing further glaucomatous visual damage if this trend is not detected.