INSTRUCTION Examine this patient's fundus. SALIENT FEATURES History · History of diplopia (monocular diplopia). · Floaters. · History of diabetes, hypertension. Examination · Small white opacities which are present in front of the retinal vessels. · The patient may complain of diplopia (monocular diplopia). Proceed as follows: Tell the examiner that you would like to: · Test for monocular diplopia. · Check urine for sugar. · Check the blood pressure. DIAGNOSIS This patient has vitreous opacities (lesions) with monocular diplopia (functional status), and has underlying diabetes mellitus (aetiology). QUESTIONS What are the causes of vitreous opacities? · Blood: diabetes, retinal vein occlusion, trauma, subarachnoid haemorrhage, sickle cell retinopathy. · Cholesterolosis bulbi, where free-floating, highly refractile crystals are seen in liquified vitreous and in patients with severe intraocular disease. · Asteroid hyalitis (Benson's disease), where whitish yellow solid bodies, con-taining calcium palmitate and stearate, are suspended in normal vitreous. Prognosis for vision is good. · Synchysis scintillans: gold or yellowish-white particles made up of cholesterol are located in the vitreous; they settle to the bottom of the eye due to gravity. Associated with previous trauma or surgery to the eye. · Other, e.g. retinoblastoma, primary amyloidosis. What are the other causes of monocular diplopia? · Opacities in the lens. · Corneal opacities. · Retinal detachment.