Scoring against diabetic retinopathy

Optometric Management, Apr 2000 by Buscemi, Philip M

Going digital will pay off in the long run.

As a point guard in basketball, my daughter learned to use her peripheral vision to "see the court." In other words, to see and feel the situation in order to play the game well.

Applying this thought to diabetic retinopathy, we may not have been seeing the court either. New studies discuss the efficacy of non-mydriatic fundus cameras with 45-degree color fundus images for screening diabetic retinopathy. (To learn more, visit www.diabetesforum.com, www.priority.co.uk/med/eye.htm or "A Telemedical Approach to the Screening of Diabetic Retinopathy: Digital Fundus Photography" in the March 2000 issue of Diabetic Care.)

Inadequate turns adequate

Topcon is supporting the growing number of diabetic screenings with its new TRC-NW6S Non-Mydriatic Digital Retina Camera. This camera, combined with a very sensitive color charge coupled device (CCD) camera, IMAGEnet 2000 and Mosaic software, enables a view of up to 94 degrees of the retina without dilation. The camera incorporates one central and eight independent peripheral internal fixation targets. You can modify sequencing and illumination of the targets to create six fixation patterns.

The patient looks at each of the fixation points, acquiring a digital image each time. Superimposing two alignment dots and centering these in an alignment scale accomplishes alignment. Focusing is easy with Vernier lines in a focusing bar.

The IMAGEnet 2000/Mosaic Software then takes all nine images and roughly aligns them. Then a manual final registration of all images is performed, yielding a mosaic covering up to 94 degrees of the retina.

Benefits

From my perspective as an active clinician, I see more uses for this technology than just diabetic screening. Having a retinal mosaic that includes the arcades and optic nerve head would make it easier to locate a lesion and monitor its potential progression.

The camera itself has been redesigned with ergonomics in mind and, according to Topcon, the joystick, monitor and patient are all in direct alignment, making image acquisition easier. The operation panel is illuminated for easy viewing in low light levels. The TRC-NW6S can take pictures in patients with pupils as small as 3.7 mm, but the field of view must be lowered to 30 degrees.

Old equipment is ancient history If you have an earlier model nonmydriatic fundus camera, you know how frustrating it can be for technicians to align patients and take pictures, only to find the exposure was wrong because the flash intensity was incorrect. And if you're using Polaroid photography, you're not only losing chair time but also material costs in wasted film.

The Topcon camera has Auto Flash Intensity to help prevent this.

The payoff helps your practice

Going digital is initially more expensive, but it quickly pays for itself in film savings. If you have a network, you may be able to use IMAGEnet 2000 to view retinal imagery with your patient in the exam lane. I use competing software to do this. It saves money, promotes better patient understanding, is great internal marketing and increases patient flow.

So take a look at the TRC-NW6S to see if it can help your practice see the court better and ultimately score against diabetic retinopathy.

Dr. Buscemi has no financial interest in Topcon. E-mail him at pbuscemi@email.msn.com, but please type "OM" in the topic field and indicate the topic.