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Darkroom prone provocative testing in primary angle closure suspects and those with open angles
David S Friedman1,2,3, Dolly Shuo-Teh Chang4, Yuzhen Jiang3
1Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland, USA david.friedman@jhu.edu.
The British Journal of Ophthalmology
|March 2, 2019
Summary
Darkroom prone provocative testing (DRPPT) did not effectively distinguish primary angle closure suspects (PACS) from open-angle controls. This IOP provocative test also failed to predict long-term clinical outcomes in PACS.
Area of Science:
- Ophthalmology
- Glaucoma Research
- Diagnostic Testing
Background:
- Primary angle closure suspects (PACS) are at risk for developing angle closure glaucoma.
- Provocative tests are used to assess the risk of angle closure.
- The darkroom prone provocative test (DRPPT) is one such test.
Purpose of the Study:
- To evaluate the efficacy of DRPPT in differentiating PACS from individuals with open angles.
- To assess the predictive value of DRPPT for long-term clinical outcomes in PACS.
Main Methods:
- A cohort of 889 PACS participants and 89 open-angle controls underwent DRPPT.
- Intraocular pressure (IOP) was measured before and after a 15-minute prone position in a darkroom.
- IOP spikes and elevations were recorded and compared between groups.
Main Results:
- PACS participants were younger, more often female, and had lower baseline IOP than controls.
- Both groups showed an IOP increase after DRPPT, with a slightly greater increase in controls.
- While a higher percentage of controls experienced an IOP spike (≥8 mm Hg) compared to PACS, the DRPPT did not predict clinical trial endpoints over 6 years.
Conclusions:
- The modified DRPPT was unable to reliably differentiate PACS from open-angle individuals.
- Although IOP elevation varied with the degree of angle closure in PACS, DRPPT did not provide insight into future risk of developing angle closure disease.
Keywords:
glaucoma
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