Funduscopy:to dilate or not to dilate?
Dilating the pupil with mydriatic eye drops before funduscopy doubles sensitivity for testing for diabetic retinopathy, but what additional risk does dilation carry? Gerald Liew and coauthors assess the evidence
Funduscopy is commonly used by non-ophthalmologists to screen for diabetic retinopathy.1 The sensitivity of funduscopy through a dilated pupil for detecting diabetic retinopathy is twice as high as detection through an undilated pupil,2 but surveys of general practitioners have found that only one in 250 regularly dilate pupils, even when assessing patients at high risk of diabetic eye disease.3 A common reason for not dilating pupils is concern about the risk of precipitating acute angle closure glaucoma.3 How big is this risk?
Recent population based studies indicate that this risk is extremely low. In the Rotterdam study of 6760 people, routine use of mydriatic eye drops in all participants aged 55 and over precipitated acute angle closure glaucoma in only two individuals (0.03%).4 The Baltimore eye survey of 4870 people found no cases of acute glaucoma precipitated by mydriasis.5 In Australia, the Blue Mountains eye study of 3654 people also