Acute Zonal Occult Outer Retinopathy

Abstract

IMPORTANCE We describe the multimodal imaging in a group of patients showing a distinct clinical entity that best represents acute zonal occult outer retinopathy (AZOOR). OBJECTIVE To propose a classification of AZOOR based on clinical fundus and multimodal imaging. DESIGN, SETTING AND PARTICIPANTS A retrospective review of patients diagnosed as having AZOOR at 2 centers. After reviewing more than 400 cases diagnosed or referred to us as AZOOR or AZOOR complex, we assembled 30 cases that fit our current definition; (48 eyes) with a median age at diagnosis of 47 years (age range, 17-86 years) and a mean follow-up period of 39 months. Twenty patients were female. Eighteen patients had initially been seen with bilateral lesions, mostly asymmetric (4 cases were symmetric). Most patients had no remarkable medical or ocular history. The median visual acuity at the time of presentation was 20/25 (range, 20/20 to 20/400). MAIN OUTCOMES AND MEASURES Multimodal imaging, including fundus photography, fluorescein and indocyanine green angiography, fundus autofluorescence imaging, and corresponding eye-tracked spectral-domain coherence tomography imaging. RESULTS Each patient was initially seen with visual symptoms of photopsia and scotoma, and most had a detectable lesion in the fundus evident clinically or detected on multimodal imaging. The clinical appearance of the AZOOR lesions varied depending on their duration and location, but some features were characteristic, including a demarcating line of the progression at the level of the outer retina and a trizonal pattern of sequential involvement of the outer retina, retinal pigment epithelium, and choroid, as well as frequent zonal progression. Advanced cases of AZOOR demonstrated disruption of the inner and outer retina and severe damage or loss of the retinal pigment epithelium and the choroid. CONCLUSIONS AND RELEVANCE A specific definition of AZOOR based on multimodal imaging is proposed to help physicians distinguish it from other diseases of the posterior fundus, including white spot syndromes and autoimmune, hereditary, paraneoplastic, toxic, and other inflammatory retinopathies.

Ultra–wide-Field Fundus Autofluorescence Findings in Patients With Acute Zonal Occult Outer Retinopathy

“…Chronically symptomatic patients in our cohort did meet trizonal criteria on autofluorescence but did not meet trizonal criteria on SD-OCT for the latter reason. Indeed, Mrejen and colleagues recognize that 3 patients in their large series did not show a trizonal pattern but rather, showed diffuse hyperautofluorescence, 35 similar to the presentation of our acutely presenting patients. We propose that acute presentation of AZOOR to a referral clinic is rare given its often insidious nature and tendency for initial misdiagnosis, and that acutely presenting AZOOR patients will have diffuse hyperautofluorescence rather than a trizonal appearance unless they have an acute on chronic presentation.…”

“…Although this study maintained a relatively strict clinical definition for AZOOR, the trizonal pattern described by Mrejen and colleagues to be pathognomonic for AZOOR 35 was not present uniformly in our cohort. They astutely describe the trizonal pattern of AZOOR on FAF to include a normal zone of autofluorescence (zone 1), a speckled hyperautofluorescent zone (zone 2), and a hypoautofluorescent zone (zone 3) thought to be associated with choroidal atrophy.…”

Relationship between Choroidal Thickness and Visual Field Impairment in Acute Zonal Occult Outer Retinopathy

“…Visual field defects in AZOOR patients are caused by outer retinal impairment and are demonstrated by decreased responses on multifocal electroretinography (ERG) [3] and disrupted ellipsoid zones detected by spectral domain optical coherence tomography (SD-OCT) [4, 5]. Fundus autofluorescence can also visualize retinal pigment epithelium (RPE) abnormalities in the affected area during the acute and chronic stages of AZOOR [6, 7]. …”

Quantitative Autofluorescence Intensities in Acute Zonal Occult Outer Retinopathy vs Healthy Eyes

“…1–4 Patients with AZOOR are typically young and female and have a history of photopsia and a blind spot in the temporal field. Lesions can be unilateral or bilateral.…”

“…Recent studies have assigned a diagnosis of AZOOR based on the presence of distinctive fundus features. 4 In short-wavelength fundus autofluorescence (SW-AF) images, these patients manifest diffuse patches of hyperautofluorescence outside of the central macula and a peripapillary hypoautofluorescence indicative of RPE atrophy. The border between lesion and nonlesion retina can be demarcated by a distinctly hyperautofluorescent line (AZOOR line).…”