INTRODUCTION TO DIRECT OPHTHALMOSCOPY      Dr Alex Hunyor      Vitreoretinal Unit      Sydney Eye Hospital

Getting Started

How to turn on direct ophthalmoscope Rheostat Filters, reticle Dioptre adjustment Examination technique      • right eye/hand/eye      • fix in distance      • red reflex

Direct Ophthalmoscopy

Landmarks      • follow retinal vessels to disc      • veins darker and thicker      • macula temporal (lateral) to disc Normal Findings      • optic disc      • retinal vessels      • macula

Cross-section of the Eye

Red Reflex - Cortical Cataracts

Red Reflex - Previous Cataract Surgery

Absent Red Reflex - Mature Cataract

Normal Posterior Pole - (Fundus Camera View)

Normal Posterior Pole - (Fundus Camera View)

Direct Ophthalmoscope View

Normal Findings

Optic disc      • Colour: optic cup vs neuroretinal rim      • Shape: round, oval, tilted      • Margins: sharp, blurred      • Cup/Disc ratio: normal range, symmetry

Optic Disc (Optic Nerve Head)

• Colour: pink      • Shape: sl vertical oval      • Margins: well defined      • Optic cup: depressed central area      • Look at retinal vessels going over edge of cup        • Cup/Disc ratio 0.3

Normal Findings

Retinal Blood Vessels      • Veins are wider and darker      • Normal ratio of calibre of arteries to veins (A-V ratio) is 3:2      • May be abnormal due to narrowing of arteries or dilation of veins      • May observe changes at arteriovenous crossings (A-V nipping)

Retinal Blood Vessels

Normal Findings

Macula      • Centre of macula approx 2 disc diameters from edge of the optic disc and slightly lower      • No retinal blood vessels in centre of macula      • Foveal light reflex in younger people

Macula

• No foveal reflex in this photo      • Darker pigment      • Absent retinal vessels in fovea (centre of macula)

Myopic Fundus Changes: -10 dioptres

Myopic Fundus Changes: -18 dioptres