Direct Direct OphthalmoscopyOphthalmoscopy

By Thomas Anders BrevikBy Thomas Anders Brevik

What is it used for?What is it used for?

Examine the retina Examine the retina and its structuresand its structures

Also known as Also known as funduscopy funduscopy (examination of the (examination of the fundus)fundus)

Turning the dial to positive (or green) numbers Turning the dial to positive (or green) numbers increases the refractive index – short focal length increases the refractive index – short focal length lenses – for examining cornea, iris, or opacities in lenses – for examining cornea, iris, or opacities in vitreous or lens. e.g. start at +20 and use the slit vitreous or lens. e.g. start at +20 and use the slit lightlight

Turning the dial to negative (or red) numbers Turning the dial to negative (or red) numbers decreases – infinite focal length lens that fits your decreases – infinite focal length lens that fits your refractive power (individual) – for examining refractive power (individual) – for examining retina, start at +10 as you move in and dim the retina, start at +10 as you move in and dim the scope light about halfwayscope light about halfway

Rule of thumb: You will focus on the retina with Rule of thumb: You will focus on the retina with same number as your refractive error, then same number as your refractive error, then correct for your patients refractive errorcorrect for your patients refractive error

Have patient sit in a comfortable positionHave patient sit in a comfortable position Tell them to look at something straight Tell them to look at something straight

ahead and level over your shoulderahead and level over your shoulder Dim light in the room, so patients pupils Dim light in the room, so patients pupils

dilate a little. You can also use mydriatic dilate a little. You can also use mydriatic eyedrops to dilate the pupileyedrops to dilate the pupil

Hold ophthalmoscope in same hand as eye Hold ophthalmoscope in same hand as eye you are looking at, and looking through you are looking at, and looking through (e.g. left hand for examining patients left (e.g. left hand for examining patients left eye, using your left eye)eye, using your left eye)

Hold head steady with thumb above Hold head steady with thumb above eyebrow, or hold shouldereyebrow, or hold shoulder

At about 30cm distance with light on eye, locate red At about 30cm distance with light on eye, locate red reflex (seen as an orange glow in the pupil)reflex (seen as an orange glow in the pupil)

Follow red reflex into the eye as 15 degrees lateral to Follow red reflex into the eye as 15 degrees lateral to the patients line of vision, this will get you directly the patients line of vision, this will get you directly into the optic discinto the optic disc

If you cannot find the disc, trace any blood vessels If you cannot find the disc, trace any blood vessels back to itback to it

Examine vessels in all 4 quadrants of eye (upper and Examine vessels in all 4 quadrants of eye (upper and lower nasal and temporal quadrants)lower nasal and temporal quadrants)

Identify macula – slightly darker pigmented area, 2 Identify macula – slightly darker pigmented area, 2 optic disc widths lateral away from the optic discoptic disc widths lateral away from the optic disc

You can tell the patient to look at the light – this will You can tell the patient to look at the light – this will put the macula in your focus, however don’t look at it put the macula in your focus, however don’t look at it too long as it can be irritatingtoo long as it can be irritating

Structures of the retinaStructures of the retina

nasal temporal

1 The size, shape and borders of the optic 1 The size, shape and borders of the optic discdisc

2 The disc to cup ratio2 The disc to cup ratio 3 The relative size of the arteries and veins3 The relative size of the arteries and veins 4 The texture of the retina4 The texture of the retina 5 The color of the retina5 The color of the retina 6 Trace the vascular structure to the 6 Trace the vascular structure to the

equator of the retina.equator of the retina. 7 Find the macula and note its color and 7 Find the macula and note its color and

sizesize

GlaucomaGlaucoma

Identify disc-to-cup Identify disc-to-cup ratioratio

The pink rim of disc The pink rim of disc contains nerve contains nerve fibers. The white cup fibers. The white cup is a pit with no nerve is a pit with no nerve fibers. As glaucoma fibers. As glaucoma advances, the cup advances, the cup enlarges until it enlarges until it occupies most of the occupies most of the disc area. disc area.

RetinoblastomaRetinoblastoma

There is a white There is a white reflex, rather than reflex, rather than red reflex when red reflex when illuminatedilluminated

Red reflex is also Red reflex is also reduced in cataractreduced in cataract

PapilledemaPapilledema

Indicates increased Indicates increased intracranial intracranial pressure, e.g. due pressure, e.g. due to hydrocephalus, to hydrocephalus, brain tumor, brain tumor, idiopathic idiopathic intracranial intracranial hypertension or hypertension or acute intracranial acute intracranial hemorrhagehemorrhage

Proliferative retinopathy Proliferative retinopathy and and

cotton-wool spotscotton-wool spotsCotton-wool spots are caused by ischemic damage to nerve fibers

Compensatory proliferation of vessels

Diabetes and hypertension are the main causes

Hypertensive retinopathyHypertensive retinopathy Arteriosclerosis with Arteriosclerosis with

moderate vascular wall moderate vascular wall changes (“copper wiring”) changes (“copper wiring”) to more severe vascular to more severe vascular wall hyperplasia and wall hyperplasia and thickening (“silver thickening (“silver wiring”) wiring”)

Arteriovenous crossing Arteriovenous crossing abnormalities abnormalities (arteriovenous nicking) (arteriovenous nicking)

These vessel changes are These vessel changes are better appreciated using better appreciated using the green light (makes the green light (makes the red retina appear in the red retina appear in grey tones)grey tones)

Age-related Macular Age-related Macular DegenetationDegenetation

Wet form: abnormal Wet form: abnormal blood vessel growth w/ blood vessel growth w/ hemorrhage and protein hemorrhage and protein leakageleakage

Dry form: Drusen Dry form: Drusen

(cellular debris) (cellular debris) build-upbuild-up

http://www.youtube.com/watch?v=AutUi09JIXY&feature=related

http://www.jaapa.com/beyond-the-red-reflex-examining-the-eye-with-an-ophthalmoscope/article/151311/