Non-mydriatic Polaroid photography in screening for diabetic retinopathy
BMJ (Clinical Research Edition)
Primary hyperparathyroidism: changes in the pattern of clinical presentation. Lancet 1980;i:1317-20. 2 Heath HW, Hodgson SF, Kennedy HA. Primary hyperparathyroidism: incidence, morbidity and potential economic impact on the community. N EnglJ Med 1980;302:189-93. Non-mydriatic Polaroid photography in screening for diabetic retinopathy SIR,-I have been using a non-mydriatic camera in a district general hospital diabetic clinic for the past three years and think that the finding by Dr D Jones and
... colleagues (9 April, p 1029) that one in five Polaroid photographs are uninterpretable is a remarkably high figure; in our experience failures are fewer than 1 in 10. The age distribution of patients in their study is not mentioned; problems caused by constricted pupils and lens opacities rise progressively over the age of 65. If both eyes are photographed at the same clinic visit we have found that the second photograph is invariably of poorer quality than the first, and our practice now is to photograph the contralateral eye at the next clinic visit. We have been screening all patients under 65 attending the diabetic clinic. Those with visual symptoms and those known to have retinopathy who were already under review by an ophthalmologist were excluded. The patients' mean age was 42-8 years (range 16-65) and mean duration of diabetes 9-8 years (range 0-47); 63% had type 1 diabetes. A total of 1166 retinas were examined with a Canon CR2-NM camera and Polaroid 779 film. Retinopathy (maculopathy, cotton wool spots, new vessels, and intraretinal microvascular abnormalities) was identified in 54 retinas (4 6%). In an ideal world diabetic patients would undergo annual fluorescein angiography or be examined through dilated pupils by a consultant ophthalmologist (although many of my patients would be unwilling to submit repeatedly to either of these experiences). This utopian situation is unlikely to occur in most district general hospital diabetic clinics and the non-mydriatic camera should not be dismissed without further evaluation.