Acute Zonal Occult Outer Retinopathy; Revisited (original) (raw)

Journal of ophthalmic & vision research

Acute zonal occult outer retinopathy (AZOOR) was first described by J. Donald M. Gass in 1992 [1] as a "syndrome" characterized by sudden onset photopsia and acute scotomas related to loss of sectors of outer retinal function in typically young, otherwise healthy individuals including 10 female and 3 male subjects. [1] Early funduscopic appearance was often normal; however, most patients developed zones of retinal pigment epithelial (RPE) atrophy or pigment clumping in one or both eyes when followed over time. [2] Persistent visual field defects, some corresponding electroretinogram (ERG) changes, retinal arterial narrowing and eventually chorioretinal atrophy were usually observed. [1,2] The pathogenesis of the disease was uncertain, but Gass stated that a virus was the best explanation for the progressive abnormalities in the fundus and no treatment modalities have shown any proven evidence of benefit. Gass speculated that AZOOR, pathologically and etiologically was related to a spectrum of so called the "AZOOR complex" and included multiple e v a n e s c e n t w h i t e d o t s y n d r o m e (M E W D S) , acute idiopathic blind spot enlargement (AIBSE) syndrome, acute macular neuroretinopathy (AMN), presumed ocular histoplasmosis (POHS), punctate inner choroidopathy (PIC), and multifocal choroiditis (MFC). [3] The basis for his speculation was that all of these disorders most commonly occurred in young adult women (similar demographic features) with primary involvement of the outer retina, and that all entities may be associated with inflammation, visual field loss and in some instances, ERG abnormalities. [2] However, the AZOOR complex differs from well-defined AZOOR and should be differentiated in order to assist ophthalmologists in the clinical setting for a particular diagnosis and management. Since the first description of AZOOR, various aspects of the disease have been evaluated in multiple publications, but this entity was ill-defined and poorly understood because of the absence of histopathology and very little knowledge of its pathogenesis. Nevertheless