Abstract
Purpose: :
To correlate functional loss by microperimetry with structural changes by optical coherence tomographic (OCT) and photographic imaging in patients with Stargardt disease.
Methods: :
We prospectively studied 18 eyes of 10 patients with Stargardt macular dystrophy. All patients underwent a full ophthalmic examination, including best corrected visual acuity, biomicroscopy, applanation tonometry, fundoscopy and fundus photography. Scanning laser ophthalmoscope (SLO) infrared imaging, spectral domain OCT (SD-OCT) scans, and microperimetry were performed using a SD-OCT/SLO-microperimetry combination system. Fundus photographs and SLO infrared images were compared and correlated to corresponding SD-OCT scans. Additionally, SLO microperimetry was performed and results were superimposed on SLO infrared images.
Results: :
Fundus photographic findings in our study population ranged from mottled hypopigmentary macular changes in 2 patients (4 eyes), a bull’s eye-appearing macular lesion in 4 patients (6 eyes) and an atrophic-appearing, geographic macular lesion in 5 patients (8 eyes). Seventeen out of 18 eyes showed a distinct hypo-reflective foveal and/or perifoveal area with distinct borders on SLO-infrared images which was less evident on fundus photographs. This hypo-reflective zone corresponded to areas of significantly elevated psychophysical thresholds on microperimetry testing, in addition to thinning of the retinal pigment epithelium, disorganization or loss of the photoreceptor cell inner-outer segment junction and external limiting membrane on SD-OCT scans.
Conclusions: :
SLO infrared fundus images are useful for depicting retinal structural changes in Stargardt patients which correspond to regions of reduced retinal sensitivity. A combined SD-OCT-microperimetry device allows for a direct correlation of these structural abnormalities with functional defects that will likely be applicable for the determination of optimal retinal areas for potential improvement of retinal function in Stargardt patients during future clinical trials and for the monitoring of the natural history of disease progression.
Keywords: retinal degenerations: hereditary • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)