Causes and Treatments of Malignant Glaucoma in the United States: Analysis of IRIS® Registry.

Purpose: To investigate the causes and treatments of malignant glaucoma (MG) in the United States.

Design: Retrospective cohort study SUBJECTS: Eyes with diagnosis codes for MG between 2014 and 2023 in the IRIS® Registry (Intelligent Research in Sight).

Methods: Precipitating procedures and treatment modality were identified using procedure codes and medication data. Using generalized estimating equations, we investigated factors associated with initial treatment with pars plana vitrectomy (PPV), those associated with undergoing laser or incisional surgeries after medication, and those associated with undergoing surgery or cyclophotocoagulation after laser hyaloidotomy.

Main outcome measures: The primary outcomes were a breakdown of precipitating procedures and treatment modalities. The secondary outcomes included factors associated with initial treatment with PPV and those associated with undergoing additional procedures after medication or laser hyaloidotomy.

Results: A total of 3554 eyes were diagnosed with MG, among which pre-existing glaucoma was identified in 54.5%. Cataract surgery was the most common precipitating surgery (26.6%), and estimated incidence rate was the highest after tube shunt surgery (23.8/10 000). First-recorded treatment was medication in 54.8%, laser hyaloidotomy in 8.9%, and PPV in 31.9%. Higher intraocular pressure (IOP) at onset (odds ratio: 1.08 [95% confidence interval: 1.03-1.12] per 10 mmHg) and worse visual acuity at onset (odds ratio: 1.27 [95% confidence interval: 1.19-1.35] per 1 unit higher logarithm of the minimum angle of resolution) were associated with initial PPV; 34% and 24% of the eyes underwent additional procedures after medication and laser hyaloidotomy, respectively. Factors associated with subsequent procedures among medically treated eyes included aphakia or pseudophakia (odds ratio: 1.33 [95% confidence interval: 1.09-1.63]) and higher IOP at onset (odds ratio: 1.11 [95% confidence interval: 1.05-1.17] per 10 mmHg). Higher IOP at onset (odds ratio: 1.19 [95% confidence interval: 1.03-1.38] per 10 mmHg) was also associated with additional procedures after laser hyaloidotomy.

Conclusions: More than half of the eyes with MG had a pre-existing glaucoma diagnosis. Tube shunt surgery had the highest incidence rate of MG. More than half were initially treated with medication, and one-third were initially treated with PPV. Higher IOP at onset was associated with a higher likelihood of being initially treated with PPV as well as a higher likelihood of requiring additional procedures when initially treated with medication or laser hyaloidotomy.

Financial disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.