Abstract
Purpose: :
Patterns of fundus autofluorescence (FAF) and near infrared autofluorescence (NIA) are variable in patients with cone-rod dystrophies (Kellner et al, Ophthalmologe, 2009, in press). They may appear relatively normal, show rings of pericentrally increased FAF and NIA as well as severe loss of FAF and NIA intensity. The purpose of the present study was to evaluate the retinal structure with spectral domain optical coherence tomography (sdOCT)in correlation with FAF and NIA alterations.
Methods: :
Twelve patients with cone-rod dystrophies (diagnosed with clinical evaluation and full-field ERG recording according to ISCEV standards) underwent evaluation of FAF and NIA (Heidelberg Retina Angiograph 2, Heidelberg Engineering, Heidelberg, Germany) as well as sdOCT (Spectralis HRA, Heidelberg Engineering, Heidelberg, Germany).
Results: :
The mildest sdOCT alterations were subfoveal disruption of the photoreceptor layer correlating with subfoveally increased FAF and NIA. In more progressed stages, loss of photoreceptor layers in the macular area correlated to similar areas of increased or decreased FAF and NIA. In the most severe cases, severe alterations of the photoreceptor layers were observed in all sdOCT images of the posterior pole correlating to FAF and NIA alterations extending beyond the vessel arcades. In one patient, a subfoveal cystic area with loss of outer retinal layers was detected bilaterally without leakage on fluorescein angiography.
Conclusions: :
The area of FAF and NIA alterations in cone-rod dystrophies correlates with photoreceptor layer abnormalities observed with the sdOCT. The combination of all three methods provides a detailed analysis of retinal and retinal pigment epithelial structure and facilitates a detailed follow-up of disease progression.
Keywords: retinal degenerations: hereditary • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • macula/fovea