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The objective was to evaluate digital images of the retina from a handheld fundus camera (Nidek NM-100) for suitability in telemedicine screening of diabetic retinopathy. A handheld fundus camera (Nidek) and a standard fundus camera (Zeiss) were used to photograph 49 eyes from 25 consecutive patients attending our diabetic clinic. One patient had cataracts, making it impossible to get a quality image of one of the eyes (retina). The Nidek images were digitized, compressed, and stored in a Fujix DF-10M digitizer supplied with the camera. The digital images and the photographs were presented separately in a random order to three ophthalmologists. The quality of the images was ranked as good, acceptable or unacceptable for diabetic retinopathy diagnosis. The images were also evaluated for the presence of microaneurysms, blot hemorrhages, exudates, fibrous tissue, previous photocoagulation, and new vessel formation. κ Values were computed for agreement between the photographs and digital images. Overall agreement between the photographs and digital images was poor (κ < 0.30). On average, only 24% of the digital images were graded as being good quality and 56% as having an acceptable quality. However, 93% of the photographs were graded as good-quality images for diagnosis. The results indicate that the digital images from the handheld fundus camera may not be suitable for diagnosis of diabetic retinopathy. The images shown on the liquid crystal display (LCD) screen of the camera were of good quality. However, the images produced by the digitizer (Fujix DF-10M) attached to the camera were not as good as the images shown on the LCD screen. A better digitizing system may produce better quality images from the Nidek camera.

The digital images of the optic disk from a portable fundus camera were evaluated for suitability in teleophthalmologic screening for glaucoma.

Background:Digital imaging systems provide immediate, magnified images that can easily be analysed, enhanced, archived, printed on near photographic-quality paper and transferred electronically to remote computers. We have assembled a digital ophthalmic system and tested it on patients with some common causes of blindness: corneal scarring and cataract, diabetic retinopathy, macular degeneration and glaucoma. Methods:Digital images were obtained using a variety of ophthalmic imaging devices ranging from slit-lamp, fundus camera, indirect ophthalmoscope and scanning laser ophthalmoscope. These images were compressed in order to concentrate image information (image size reduced by 90–95%) and minimize transmission time (reduced by 97–98%). Standard or mobile telephone lines were used to transmit images to remote terminals. Results/Discussion:Transmission time was reduced from 15–20 min to 20-30s and the image size was reduced from 1.3MB to 20-30kB by compressing the images before transmission. Image quality is still excellent