Abstract
Purpose: :
To study 25 cases of AZOOR whose diagnosis was strictly based on clinical descriptions by J. Donald Gass1, to examine clinical characteristics, visual field scotomata patterns, and measure presence or absence of anti-retinal antibodies.
Methods: :
Twenty-five patients with histories of sudden visual loss, photopsias and appearance of missing areas in their vision were assessed for AZOOR based on the characteristic onset, abnormal ERGs, and scotomatous changes seen on standardized visual field testing. The presence of enlarged blindspots, or large scotomatous areas contiguous with blindspots were definitive criteria for classification of AZOOR. Several patients with large scotomata in peripheral retina, as described by Gass, were also designated as cases of AZOOR. Western blots were used to detect anti-retinal antibodies in a standardized fashion.
Results: :
The majority of AZOOR patients were women 21/25 (84%) and 15/25 (60%) of the patients had personal or family histories of autoimmune disease. Western blots from AZOOR patients showed an average of 6.5 immuno-reactive bands compared to 4.5 for a comparative group of 25 autoimmune retinopathy patients. Characteristic visual field changes included enlarged blind spots (15/50 eyes), central scotomata, and large scotomata connecting to or contiguous to the blindspot (24/34), and visual field isopter contraction (18/34) was common. We examined the retinal changes associated with the enlarged blindspots, reviewing fluorescein angiograms or autofluorescent photographs in corresponding areas; we found peripapillary retinal changes (staining or depigmentation) often matching the shape of the scotomata found on Goldmann visual field, suggesting that anti-retinal antibodies are accessing the retina and subretinal space via the optic canal where there is frequently a loss in the RPE confluence and their tight junctions normally protecting the retina.
Conclusions: :
This study strongly suggests that AZOOR is a form of acute-onset autoimmune retinopathy, in which the distinctive visual field patterns, in part, are the result of a breakdown of the blood-retinal barrier at the optic canal or peripapillary retina, allowing spread of anti-retinal antibodies in the subretinal space where they can cause damage to the RPE and photoreceptors directly, depending on their antigenic targets. Funded investigations into all forms of autoimmune retinopathy are badly needed, since knowledge-based treatments are likely save vision in these patients. 1 Am J Ophthalmol. 2002 Sep;134(3):329-39
Keywords: autoimmune disease • retina • chorioretinitis