- The intriguing concept of a blinding retinal disorder that is invisible to ophthalmoscopy (“occult”) can be traced to the late Dr. Donald Gass.
- Gass introduced the term AZOOR (Acute Zonal Occult Outer Retinopathy) in 1993 by reporting 13 cases with acute onset of vision loss in various zones of the visual field with normal (or nearly normal) ophthalmoscopic exams.1 However, reduced amplitude ERGS in these patients confirmed photoreceptor (or “outer retina”) dysfunction.
- A recent exam of one of the original 13 cases, 23 years after her initial onset of vision loss, reveals the surprising progression of AZOOR.
- Alternatively, it may reveal that the presenting symptoms and findings 23 years ago were atypical for what now appears to be advanced RP.