Direct Ophthalmoscopy
By Thomas Anders Brevik


What is it used for?
nExamine the retina and its structures
nAlso known as funduscopy (examination of the fundus)
n
BETA200S_LG

nTurning the dial to positive (or green) numbers increases the refractive index – short focal
length lenses – for examining cornea, iris, or opacities in vitreous or lens. e.g. start at +20 and
use the slit light
nTurning the dial to negative (or red) numbers decreases – infinite focal length lens that fits
your refractive power (individual) – for examining retina, start at +10 as you move in and dim the
scope light about halfway
nRule of thumb: You will focus on the retina with same number as your refractive error, then
correct for your patients refractive error

nHave patient sit in a comfortable position
nTell them to look at something straight ahead and level over your shoulder
nDim light in the room, so patients pupils dilate a little. You can also use mydriatic eyedrops to
dilate the pupil
nHold ophthalmoscope in same hand as eye you are looking at, and looking through (e.g. left hand
for examining patients left eye, using your left eye)
nHold head steady with thumb above eyebrow, or hold shoulder

nAt about 30cm distance with light on eye, locate red reflex (seen as an orange glow in the pupil)
nFollow red reflex into the eye as 15 degrees lateral to the patients line of vision, this will get
you directly into the optic disc
nIf you cannot find the disc, trace any blood vessels back to it
nExamine vessels in all 4 quadrants of eye (upper and lower nasal and temporal quadrants)
nIdentify macula – slightly darker pigmented area, 2 optic disc widths lateral away from the optic
disc
nYou can tell the patient to look at the light – this will put the macula in your focus, however
don’t look at it too long as it can be irritating

Structures of the retina
retina
nasal
temporal

n1 The size, shape and borders of the optic disc
n2 The disc to cup ratio
n3 The relative size of the arteries and veins
n4 The texture of the retina
n5 The color of the retina
n6 Trace the vascular structure to the equator of the retina.
n7 Find the macula and note its color and size

Glaucoma
nIdentify disc-to-cup ratio
nThe pink rim of disc contains nerve fibers. The white cup is a pit with no nerve fibers. As
glaucoma advances, the cup enlarges until it occupies most of the disc area.
disctocup

Retinoblastoma
nThere is a white reflex, rather than red reflex when illuminated
n
n
n
n
nRed reflex is also reduced in cataract
Fundus_retinoblastoma Rb_whiteeye

Papilledema
nIndicates increased intracranial pressure, e.g. due to hydrocephalus, brain tumor, idiopathic
intracranial hypertension or acute intracranial hemorrhage
papilledema1

Proliferative retinopathy and
cotton-wool spots
Proliferative_retinopathy_EDA01
Cotton-wool spots are caused by ischemic damage to nerve fibers
Compensatory proliferation of vessels
Diabetes and hypertension are the main causes

Hypertensive retinopathy
nArteriosclerosis with moderate vascular wall changes (“copper wiring”) to more severe vascular
wall hyperplasia and thickening (“silver wiring”)
nArteriovenous crossing abnormalities (arteriovenous nicking)
nThese vessel changes are better appreciated using the green light (makes the red retina appear in
grey tones)
9-23

Age-related Macular Degenetation
nWet form: abnormal blood vessel growth w/ hemorrhage and protein leakage
armdretina asdas
nDry form: Drusen
  (cellular debris) build-up

nhttp://www.youtube.com/watch?v=AutUi09JIXY&feature=related
nhttp://www.jaapa.com/beyond-the-red-reflex-examining-the-eye-with-an-ophthalmoscope/article/151311
/