Abstract
Abstract: :
Purpose: To improve imaging of Optic Nerve Head Drusen (ONHD) autofluorescence (AF) using the Heidelberg Retina Angiograph (HRA) confocal scanning laser ophthalmoscope (cSLO). To obtain three-dimensional (3D) information on ONHD with AF tomography. Methods: We used the HRA cSLO to acquire optic nerve head images with infrared (IR) light and with blue light eliciting AF. We obtained images at 20x20 and 10x10 degrees scan fields at 512x512 pixel resolution. We always averaged 4 to 32 images, improving signal to noise ratio. For tomography, we acquired a stack of 32 512x512 pixel section images at different depths. We examined 11 patients, 3 of them with monolateral ONHD and 8 of them with bilateral ONHD. The drusen were previously demonstrated by either ophthalmoscopy, conventional AF imaging with a fundus camera (Topcon TRC-50X), or CT scans. Results: In all the patients examined, HRA-AF imaging allowed detection of the ONHD. As compared to conventional fundus camera imaging, HRA-AF imaging significantly improved visualization of drusen details and pattern, also in patients with pseudo-papilledema of uncertain etiology. AF tomography allowed delimitation of drusen in the depth (z) axis, showing that drusen in the same optic nerve head can lie at different depths. Conclusion: Intrinsic AF detected with a cSLO can significantly improve ONHD imaging. Moreover, AF tomography performed with the same instrument allows 3D characterization of drusen. We need a large cohort of patients, expecially to compare this to other methods.
Keywords: 432 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • 487 neuro-ophthalmology: optic nerve • 486 neuro-ophthalmology: diagnosis