Abstract
Abstract: :
Purpose: Wide–angle Optomap images obtained from the Panoramic200 device captures a 200° field of the ocular fundus without dilation. In contrast, conventional digital imaging through a dilated pupil typically includes the disc and macula as the main image field. Peripheral fields must be specifically imaged in addition, if required. In this study, the accuracy of macular diagnoses made from macular images of the same eye obtained with both 50° and 200° imaging system types were compared. Methods: Thirty–five eyes were digitally imaged with both the Panoramic200 and the Topcon TRC50 50° fundus camera. Thirty–two eyes with macular disease and 3 normal eyes were studied. Images were randomly presented on a color–viewing monitor to the same retinal specialist (TRF) in a masked manner devoid of clinical information. Both color and red–free images were viewed. Diagnoses made from images acquired by each image system were compared to one another for accuracy, using the clinical diagnosis made on complete retinal examination and fluorescein angiography as the standard. Results: Diagnoses included normal fundus, background and proliferative diabetic retinopathy, macular edema, dry and wet age–related macular degeneration, branch and central retinal vein occlusion, and perivascular lattice degeneration. Using the conventional Topcon image system, correct macular diagnoses were made in 83% of eyes, while using the wide field Optomaps, correct diagnoses were made in 71% of eyes. Errors included mistaking vascular occlusion for diabetic retinopathy in poor quality images due to media opacities, and non–detection of macular edema with both imaging systems. In neither imaging system were eyes with macular disease categorized as normal. The difference between results using these 2 imaging methods was not statistically significant using Chi square analysis (P = 0.25). Conclusion: The Panoramic200 non–mydriatic imaging system renders the macula in a substantially detailed fashion allowing correct diagnoses to be made in a high percentage of cases. Factors such as reduced image resolution in an ultrawide field and imaging artifacts in some studies make diagnoses from Optomap images incrementally more difficult to make. On the other hand, the 200° wide field can display additional peripheral findings which may have relevance on the macular diagnosis, but are missed during conventional imaging. Neither imaging technique yielded many false positive results (0), suggesting that both are suitable for use in screening, although dilation of the pupil is needed for conventional studies.
Keywords: imaging/image analysis: clinical • retina • macula/fovea