Indirect ophthalmoscopy

Introduction

• To examine the eye especially the fundus.

Uses

• Large field examination of fundus.

Advantages

• Enables view of fundus through cloudy media or around partial intra-ocular opacities which make direct ophthalmoscopy more difficult.
• Excellent survey technique allowing large field of view and stereopsis.
• Allows easier examination of peripheral fundus than direct ophthalmoscopy.
• Greater working distance → increased safety for examiner and less restraint of patient.
• Facilitates determination of fundus depressions and elevations.
• Both hands are on patient's head with binocular indirect technique, so fundus examination is faster and comparison between eyes is easier.
• A supplemental mirror can be attached to many binocular indirect models, permitting simultaneous visualization by examiner, student, colleague or client.

Disadvantages

• Low magnification (2-4 times).
• Inverted, virtual image.
• Equipment is expensive with binocular models, but simple bupe lens and pen torch inexpensive for monocular indirect technique.

Preparation

• 20 min for mydriatics to work if being used.

Requirements

Materials required

Minimum equipment

• Focal light source and hand lens = monocular indirect ophthalmoscopy.
• Monocular hand-held Oculus (Storz).

Ideal equipment

• Binocular indirect ophthalmoscope.
• Types available include: All Pupil (Keeler Optical Products Inc.), Fison (Keeler Optical Products Inc.), and Heine Omega/binocular indirect ophthalmoscopes (Heine USA Ltd).

Minimum consumables

• Mydriatic, solution of 1% tropicamide .

Other requirements

• Dark room.

Sources

Publications

• Recent references from PubMed.