Purpose
To evaluate the feasibility and efficacy of ultra-widefield fluorescein angiography (UWFFA) utilizing the Heidelberg Spectralis® platform.
Methods
Initially, nine patients (17 eyes) underwent UWFFA using the ultra-widefield module in the Heidelberg Spectralis® HRA+OCT system. Utilizing 55 and 102 degree non-contact lens for the Spectralis® imaging platform with peripheral sweeps and stitching software, images were obtained for a variety of disease states. In all patients, fluorescein angiography of the retinal vasculature was obtained simultaneously. Utilizing previously described methods, Adobe® Photoshop® C5 software was used to outline and calculate the number of pixels in the widefield, ultra-widefield and stitched images. Two reviewers evaluated each image to quantify the ability of each modality to illustrate peripheral retinal vasculature.
Results
All 17 eyes had adequate single image capture, though only 10 were sufficient for stitched peripheral sweeps. All 55 degree images were resized to an appropriate aspect ratio based on optic nerve head measurements. The 55 degree single shot captured a total retinal area averaging 66,518 pixels (range 66,120 to 67,062), while the areas captured using the 102 single shot and 102 degree stitched peripheral sweeps were 110,557 pixels (range 90,836 to 115,529) and 209,460 pixels (range 187,792 to 230,206), respectively (P<0.0001).
Conclusions
The Heidelberg Spectralis® platform with a non-contact lens is a viable method for obtaining UWFFA to aid in the imaging of peripheral vascular diseases. The standard photographic image is 30 degrees, however, non-contact attached lenses can image at 55 and 102 degrees. Sweeping the image is possible with the ultra-widefield 102 degree lens to allow greater coverage of the retinal periphery to greater than 150 degrees. While non-contact Spectralis based UWFFA is a relatively new addition to retinal imaging, this modality aids in improved detection and treatment of peripheral disease when compared to traditional retinal imaging modalities. Acknowledgements: Supported by Research to Prevent Blindness
Keywords: 688 retina •
552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
550 imaging/image analysis: clinical