Abstract
Abstract: :
Purpose: To assess the utility of the Optos Panoramic 200 non-mydriatic widefield imaging system for the diagnosis of retinal pathology and its management. Method: Patients scheduled for a routine retinal exam in a university retina practice had both eyes imaged using the non-mydriatic Panoramic 200 camera prior to a dilated clinical fundus exam. Months later, 50 of a total of 135 patient wide-angle images were arbitrarily selected and reviewed by two retinal specialists in a masked manner. The eye with the most severe pathology was chosen for comparison for each patient. In addition to diagnosis, the suggested time to next appointment and proposed intervention were determined from the images. The parameters determined from the Optos images were then compared to those generated by clinical exam, which included slit lamp biomicroscopy of the fundus. The iris color and image quality (judged as excellent, good, fair or poor) were also noted. Results: In 45 of our sample of 50 eyes (90%), the correct diagnosis (including lack of disease) was made from Optos images by one specialist and in 38 of 50 (76%) by the other. The positive predictive value for diagnosing retinal pathology was as high as 97%. The negative predictive value was as high as 75%. The sensitivity was 90% and 73% for the two specialists while the specificity was 89% and 71%. These differences between reviewers are in part due to whether or not image enhancement was used on poorer image quality images. In 38 cases (76%) follow-up as determined from images agreed with that recommended on the basis of the clinical exam. The quality of images was deemed to be good or excellent in 50% and 60% of images respectively by the two retinal specialists. In some cases, artifacts in the macular region precluded accurate diagnosis of more subtle abnormalities. Concerning iris color, poor image quality occurred in 14 % of brown eyes, 8% of hazel eyes, and 13% of blue eyes. 28 of the 50 patients were diabetic. Of the eye chosen for comparison, 7 eyes had prior PRP (scars of which offer clues to the physician screeners). The Optos and clinical exam were consistent in diagnosing stable PDR versus continued proliferation requiring further PRP. The images from patients without prior PRP were diagnosed correctly via Optos images by one specialist in 2 of 2 eyes with PDR, 3 of 4 eyes with BDR, 4 of 6 eyes with CSME, 2 of 2 eyes with normal fundi and 3 of 4 eyes with stable maculopathy status post laser. Conclusion: The Optos Panoramic 200 non-mydriatic widefield imaging system is a potentially valuable screening tool for the diagnosis of retinal pathology and determination of appropriate management.
Keywords: 430 imaging/image analysis: clinical • 554 retina • 388 diabetic retinopathy