Abstract
Purpose :
To compare optical coherence tomography (OCT) images obtained from a combined ultrawidefield (UWF) device with images from a stand-alone OCT instrument.
Methods :
A prototype imaging device combining UWF scanning laser ophthalmoscopy (SLO) with OCT (Optos, Inc.) was used to collect images from eyes with various retina pathologies including AMD, DME, DR, macula holes, epiretinal membrane, and others. For comparison, images were also collected with a stand-alone SD-OCT device (Optos Model E). A total of 35 retina patients in all were imaged. The UWF SLO uses red and green lasers and captures retinal images extending out to 200 degrees including the macula and far periphery (3900x3072 pixels). The SD OCT aspect of the new device scans at a rate of 70,000 A scans per second and covers an area up to 12mm x 9 mm of the macula and optic disc (1024 A scans x 65 B-Scans). The device captures the UWF SLO images first, followed by the OCT images which are then registered to the UWF image. The obtained images were reviewed by two retina specialists (SS and MS) and clinical features relevant to pathology were evaluated. In addition, the visibility of two key structures used in reading center assessments of image quality, the external limiting membrane (ELM) and the choroid, were compared between devices.
Results :
Disease features evident on the OCT B-scans included drusen, atrophy, pigment epithelial detachment, cystoid macular edema, ellipsoid zone disruption, subretinal drusenoid deposits, nerve fiber layer thinning, vitreo-macular traction, and epiretinal membrane. All features were identified similarly between devices in all cases in this series. The ELM could be visualized in the line scan in 97% of the cases for both the UWF and the full extent of the choroid (without enhanced depth imaging) could also be seen in 69% of the cases with the UWF+OCT device, and in 60% of the cases with the OCT only device. Notably, because companion UWF SLO images were available with the combined device, additional lesions (e.g. drusen, hemorrhages) could be observed beyond the OCT scanning field
Conclusions :
An OCT integrated into a UWF device provides excellent and similar visualization of retinal structural details in eyes with disease compared to a stand-alone OCT device. Given the established benefits of UWF imaging, combination may prove to be a useful tool in clinical practice.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.