Year 1 MBChB Clinical Skills Session Ophthalmoscopy

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1 Year 1 MBChB Clinical Skills Session Ophthalmoscopy Reviewed & ratified by: Dr V Taylor-Jones, Mr M Batterbury Consultant Ophthalmologist

2 Learning objectives o To understand the anatomy and physiology of the external and internal eye and apply it to the practical skill o To understand the basic use of an ophthalmoscope and be able to identify a basic structure in your partner's eye The Ophthalmoscope Indications for Ophthalmoscopy Ophthalmoscopy is performed for: o Trauma around or of the eye itself o Routine diabetic check o As part of a neurological examination o Deteriorating vision o Symptoms associated with visual problems Headaches This enables you to turn on the light source and dim or brighten as necessary. When turning the rheostat some ophthalmoscopes have a lock switch which has to be depressed at the same time This is a wheel which can be operated from either side by rotating up wards or downwards you can alter the degree of focus As the focus wheel is turned the number reflecting the degree of focus (the selected lenses) you have selected is displayed here

3 Holding the Ophthalmascope o Hold instrument in right hand, held to right eye to look in patient s right eye and vice versa. o Hold the instrument with the index finger resting on the focusing wheel and the thumb on the rheostat. o At the start of the examination, you will be inspecting the anterior segment of the eye, and therefore you will rotate the lens wheel to magnify your view. The lens value will change- to give a positive dioptre (magnified view, like reading glasses) the lens value should be green. Once you have finished examining the anterior segment, you will rotate the focus wheel to return to 0. o Select a wide mask. o Limit the brightness of the beam using thumb - too bright a beam is uncomfortable. o The instrument MUST be held close to the examiner s eye nestled against the supraorbital ridge or against glasses if worn o Look through the aperture with one eye and close the other, or leave open if you prefer

4 Indications for Ophthalmoscopy A patient may have ophthalmoscopy performed if they present; o For a routine health check o For an occupational health check o For a diabetes check o For a check if they suffer with hypertension o With changes in vision o With pain o Following trauma (head/ eye) o With a foreign body Or this may be done as part of a cranial nerve assessment. This list is not exhaustive. Patient safety

5 Considerations Whilst explaining the procedure to the patient, consider; o That a mydriatic agent (drug resulting in pupil dilation) may be required or the lights should be dimmed to dilate the pupils o Asking the person to fix their gaze on a distant object o Placing your free hand on the forehead of the patient - this sets the distance from which to approach and avoids clashes of head as you get nearer. Also the thumb can be used to hold the upper eyelid open Image attributed Nutschig at the English language Wikipedia

6 Inspection of external structures Inspect peri-orbital tissues, eye lashes, and anterior segment for any abnormalities As you can see from this picture contact lenses are often hard to visualise.

7 Direction of approach Use the viewing eye to direct the beam of light onto the patient s eye from metre (arm s length) Approach from an angle of to the line of gaze Approach on the same level as the equator of the patient s eye This approach directs the beam towards the optic disc, an important landmark.

8 Ophthalmoscopy Note the red reflex and use this to guide you in closer to the pupil. The examiner s eyes should be at the same level as the patients. When close to the eye, use the focusing wheel to fine tune your focus on the retinal structures Red eye reflex, on a patient with blue eyes and dilated pupils.

9 Optic disc (blind spot) & optic cup The correct approach should bring you on or near to the optic disc;

10 The view of the retina Document all findings clearly and ensure all abnormalities reported to your supervisor.

11 Examination of the vessels Once a vessel is found you should follow the vessel as far as possible to look for abnormalities The retinal vessels branch into the 4 quadrants of the eye; o Superior nasal and temporal o Inferior nasal and temporal Use the quadrants when describing the retina of any abnormalities.

12 The Retina If you miss or lose the optic disc: any branching of vessels form a V, the point of the V always points towards the optic disc. The main vessels branch out in four directions Veins are uniform and burgundy in colour whereas arteries have a central pale line and two outer red walls Normal retina, right eye with some pigmentation at optic disc. Häggström, Mikael (2014). "Medical gallery of Mikael Häggström 2014". WikiJournal of Medicine 1 (2). DOI: /wjm/ ISSN Public Domain

13 The retina - what to note Optic disc: Look for; o Sharpness o Colour o Optic cup appearance Arteries and veins: Consider; o Are they tortuous or straight o The width and colour Patients with darker irises may be more difficult to examine as there retina may also appear darker. Glossary o Mydriatic A drug that causes pupillary dilatation, aiding eye examination, eg; atropine/ phenylephrine drops Peer Feedback 06 Y 1 Ophthalmoscopy pe

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