How to Use the Direct Ophthalmoscope: Neuroscience Course Teaching Lab

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How to Use the Direct OphthalmoscopeNeuroscienc
e Course Teaching Lab

• Amy M. Fowler, M.D.
• Ophthalmic Plastic and
• Reconstructive Surgery
• UNC Department of Ophthalmology
• Chapel Hill, North Carolina

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Objectives

• Learn correct use of the direct ophthalmoscope
• Recognize normal retinal anatomy
• Identify ocular anatomy
• Review abnormal retinal findings
• Identify pathologic findings

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Ophthalmoscope head removable

• Dial for lens power
• Operate with index finger
• Power indication (in diopters)
• On opposite side
• Red minus power, myopia
• Black or green plus power, hyperopia

• On/off dial
• Operate with index finger
• Press button down and rotate to adjust brightness

Some models unscrew to allow wall plug in

• Handle
• Right hand for right eye
• Left hand for left eye

Bottom unscrews to replace battery
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Some models with lens protector over viewing
window
Green filter red free (for vessels) No filter
everyday use Dimmer for photophobia
Pattern selector Small/medium/large light Blue
light Slit light Grid pattern
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Pattern selector

• Small/medium/large light
• Determined by pupil size smaller pupil use
  small light
• Photophobia use smaller light for patient
  comfort
• Blue light
• Fluorescein stained abrasions are apple green in
  cobalt blue light
• Slit light
• Poor mans slit lamp
• contour
• Grid pattern
• Measure size

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• Examiner looks through viewing side
• Place rubber flange against examiners brow

• Right eye, right hand, right eye
• Left eye, left hand, left eye

• Helpful to place free thumb on patients brow
• Stabilizes patients head
• Orients the examiner

• Instruct patient to look slightly up
• and fix at a distant target

• Find the red reflex and follow it in
• at approx. 15 degree angle temporally

• Get close - your ophthalmoscope may even
• touch your thumb (see above)
• Get closer than in this photo!

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Anterior segment

• Higher plus power focuses closer
• Cornea
• Iris
• Lens (cataract)
• Red reflex

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Red reflex

• Assess media opacities
• High plus power
• Focus on lens
• Newborn exam!
• Landing guide (direct ophthalmoscopy)
• Dial in minus for retina

Lens opacity Cataract
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Vitreous body
Vitreous hemorrhage
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Direct ophthalmoscopy

• Rotate power dial (add minus) until vasculature
  starts to get into focus
• Find any landmark, refine focus
• Follow vessels to disc
• Branch points serve as arrows

Abnormal Right Eye
Normal Left Eye
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Retinal exam

• Disc
• Color (rim)
• Pink?
• Pallor?
• Contour
• Flat or elevated?
• Rim sharp or blurred?
• Nerve fiber layer- edema?
• Obscuration of vessels?
• Cup (normal 0.3 - 0.5)

Flat, pink, sharp disc CD 0.45
Disc edema
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Increased cupping CD 0.6
Traumatic choroidal rupture
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Vessels
Emboli

• Arteries and veins
• orange red (artery) vs. blue red (vein)
• Caliber size ratio 23 (artery-to-vein)
• Course (tortuous? beaded?)
• Crossing changes
• Hemorrhage
• flame shaped, dot /blot
• Infarct cotton wool spot
• Exudate lipid, edema
• Perivascular infiltration

Dot/blot hemorhages
AV nicking
CWS
CWS
CWS
Hypertension
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Peripheral retina
Retinal contusion Commotio Retinae

• Difficult visualization with direct
  ophthalmoscope
• Hemorrhage, edema
• Nerve fiber layer infarct
• Exudation
• Pigmentation
• Scarring

Old
Diabetic laser
Recent
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Macula - do last!

• Between vascular arcades
• Area of best vision
• Most photosensitive region
• Foveal reflex
• Drusen, RPE changes, etc.

Red-free image
Drusen
Macular degeneration
Diabetic retinopathy
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Teaching points

• Be able to use direct ophthalmoscope
• Recognize normal vs. abnormal findings
• Describe abnormal finding
• Flame shaped hemorrhages
• Disc edematous or pale
• Remember disease processes come later
• Electives
• Clerkship