A drug used to treat interstitial cystitis, Elmiron (pentosan polysulfate, Ortho), has often been linked to macular disease. Now, a study published in Ophthalmology Retina found specific characteristics of PPS maculopathy on fundus imaging may help clinicians differentiate this form of the condition from hereditary maculopathies, even in the absence of known exposure to the drug.

Researchers from Emory University looked through records spanning a five-year period that indicated unspecified hereditary retinal dystrophy, pigmentary retinal dystrophy, dystrophies primarily involving the retinal pigment epithelium and unspecified macular degeneration.

Masked graders evaluated patient images taken from color fundus photography, fundus autofluorescence and OCT and classified them as follows:

• category A – highly suggestive of PPS maculopathy
• category B – some features resembling PPS maculopathy but not classic
• category C – clearly distinct from PPS maculopathy

The study included 1,131 patients who had sufficient imaging for classification. Of these, 15 patients were judged to have findings highly suggestive of PPS maculopathy (category A), 25 patients had some features resembling PPS maculopathy but not classic (category B) and 1,091 were clearly distinct from PPS maculopathy (category C). All 10 patients with PPS maculopathy were correctly placed in category A, but five patients without PPS maculopathy were incorrectly placed in the category. 

The researchers noted their findings represent 100% sensitivity and 99.6% specificity for identification of PPS maculopathy by masked review of fundus imaging.