Long-term outcomes of laser iridotomy in Vietnamese patients with primary angle closure

Background/aims To investigate the long-term outcomes of laser peripheral iridotomy (LPI) on controlling intraocular pressure (IOP) and progression of angle closure in Vietnamese. Methods Medical charts of Vietnamese patients who were diagnosed as having primary angle-closure suspect (PACS), primary angle closure (PAC) or primary angle-closure glaucoma (PACG), and who had received LPI at least 10 years prior, in a single private practice were reviewed. The main outcomes included use of further treatments after LPI, progression rate to another classification category and ocular characteristics associated with progression. Results 359 patients with a mean follow-up period of 11.8±1.6 years after the LPI were included in this study. The proportion of patients who required additional therapies (medical, laser or surgical) to control IOP were 7.1, 42.4 and 100% in the PACS, PAC and PACG groups, respectively. Fifty-three patients with PACS (22.2%) progressed to PAC; nine patients with PACS (3.8%) progressed to PACG; and five PAC patients (5.2%) progressed to PACG. Cataract surgery was a significant factor associated with PACS eyes without progression (p=0.019). Conclusions Further medications, laser or surgery are frequently required to control IOP after LPI for eyes with PAC, especially for eyes with PACG. Lens extraction seems to play a protective role in PACS eyes. Close follow-up after LPI remains necessary to prevent progression of disease.