this ppt contains detailed information about the direct opthalmoscopy, how to use and how to interpret the certain ocular conditions like cataracts, retinal changes, any medial opacities

1. Fundus examination of eye
Direct opthalmoscopy
90D
Manisai koduri
16immo19

2. • Opthalmoscopy revolutionised eye
examinations
• It allows observation of fundus
• Diagnosis of amaurosis
• Identify and locate vitro-retinal and optical
nerve defects caused by eye diseases or
trauma.
• Examine the extent of defects to plan a proper
treatment
• Evaluate the success of treatment

3. • Charles Babbage, the mathematic genius and
inventor of today's computer, his analytical
machine, was the first to construct an instrument
for looking into the eye. He did this in 1847.
• but when showing it to the he was unable to
obtain an image with it and, thus discouraged, did
not proceed further.

4. • it was reinvented by Hermann von Helmholtz in
1851
• His device used a mirror to direct a light beam to
eye and using lenses, a much larger image of the
eye could be obtained. The apparatus helped one
to see the small veins and other minute parts of
the eye.
• Later, Swedish ophthalmologist Allvar Gull-strand
developed an improved version of the device.
• In 1915, Francis A. Welch and William Noah Allyn
invented the world's first hand-held direct
illuminating ophthalmoscope which is often
regarded as the model for the current
Ophthalmoscopes.

5. It is of two major types:
Direct ophthalmoscopy one that produces an upright, image of
approximately 15 times magnification.
Indirect ophthalmoscopy one that produces an inverted, or reversed,
direct image of 2 to 5 times magnification.
Features Direct opthalmoscopy Indirect opthalmoscopy
Condensing lens Not Required Required
Examination distance
As close to patient's eye as
possible
At an arm's length
Image Virtual, erect Real, inverted
Illumination
Not as bright; not useful in
hazy media
Bright; useful for hazy
media
Area of field in focus About 2 disc diameters About 8 disc diameters
Stereopsis Absent Present
Accessible fundus view Slightly beyond equator
Up to Ora serrata i.e.
peripheral retina
Examination through hazy
media
Not possible Possible

7. • Large/Medium/Small light source: Ophthalmoscopes usually have 2 or 3 sizes of
light to use depending on the level of pupil dilation. The small light is used when
the pupil is very constricted (i.e. well lit room, no pupil dilators used). The large
light is best if using mydriatic eye drops to dilate. Most commonly in a dark, non-
dilated pupil, the medium sized light is used.
• Half light: If, for example, the pupil is partially obstructed by a lens with cataracts,
the half circle can be used to pass light through only the clear portion of the pupil
to avoid light reflecting back
• Red free: Used to visualize the vessels and hemorrhages in better detail by
improving contrast. This setting will make the retina look black and white.
• Slit beam: Used to examine contour abnormalities of the cornea, lens and retina.
• Blue light: Some ophthalmoscopes have this feature that can be used to observe
corneal abrasions and ulcers after fluorescein staining.
• Grid: Used to make rough approximations of relative distance between retinal
lesions.

10. Advantages and disadvantages
• Uses hand held
instrument that is easily
portable
• Can be used when
difficult to use slit lamp
• Provides better picture of
cortical, posterior sub
capsular cataract than
biomicroscopy
• Use to see venous
pulsation which may not
be seen in fundus
biomicroscopy
• Requires very close
working distance (some
patients find unsettling)
• Bending required may
lead to strain injury to
back over long term
• Extend of fundus visible is
limited
• Fundus lesions can be
missed because of
difficulties in scanning

11. How to perform??

12. Procedure??
• Raise the chair to look comfortably into the
patients eye(can prevent strain injury)
• Inform the patient(im going to examine the
health of your eyes)
• Illumination (darkened/semi darkened)
• Use largest aperture beam for large pupils as it
provides large field of view
• For patients with smaller pupil intermediate size
aperture is preferred as FOV is limited and causes
larger corneal reflex with L.aperture

13. • Hold opthalmoscope in right had and use right eye to
examine patients right eye.
• Left hand/left eye/patients left eye.
• (practice makes perfect of using non dominant eye
and hand and, avoid bumping of the patients eye)
• If have reduced VA in one eye use better seeing eye
• Ask patient to remove their glasses/ if had contact
lenses then easier to perform opthalmoscopy
• If you have large astigamatsm better to wear glasses
or CL.
• Set the lens wheel to about +10 if you remove glasses
and u r myopic

14. • Place the instrument against your brow, now you
should be able to to view through aperture
• Rotate instrument 10 to 20 degrees to avoid patients
nose
• Both eyes should open to relax your accomodation
• Position the opthalmoscope about 15 degrees
temporal to patient
• Place the hand not holding the instrument on back of
the examination chair for stability
2) Set dioptric power to +10D and move closer to patient
until A.segment of eye is in focus approx at 10cm
3) Observe the clarity of media(opacities will appear as
dark areas In bright red background)
4) Estimate the location by movement…

15. • Choose a point of focus ex., iris
if opacity is posterior to iris “with”motion will be
observed when you move the beam
Anterior- against
• If opacity is anterior ex., cornea ask patient to blink, if
it moves then it is mucus or debris, if not true corneal
opacity
• Instruct patient to look up, left, down, right to view
opacities behind the iris
• Cortical lenticular opacities are most found in inferior
nasal aspect of crystalline lens

16. • Move in 15degrees temporal to patients visual
axis& decrease power of focusing lens as you
move closer
• Opacities in vitreous may observed such as
floaters, haemorrhage, asteroid bodies.
• Ask patient to look up & down and see any
floaters moving

17. • Should be as close as possible without touching
patients eye(may feel uncomfortable for both)
• As farther-smaller FOV
• If viewing 15* temporal from patiets line of sight
disc or retinal vessels should be in view.
• If both you and patient are emmetropic and your
accommodation is at rest the dioptric value on lens
wheel should be Zero
• If both are ammetropic the lens power to focus
should be sum of R.error and accomodative state.

18. • If you don’t see the disc, focus on vessels
follow them backwards towards the disc.
• The bifurcation of vessels forms V and this will
point in direction to get disc
• Once you focus the disc clearly bracketing
several lens positions estimate cup cup,disc
ratios, shape and colour and clarity of disc
margins, arterio venous crossings, venous
nipping, venous pulsation…….

19. • Staphyloma:is an abnormal protrusion of the uveal
tissue through a weak point in the eyeball.
• Peripapillary atrophy:-is a clinical finding associated
with chorioretinal thinning and disruption of the retinal
pigment epithelium (RPE) in the area surrounding the
optic disc.
• Choroidal crescentA:myopic crescent is a moon-shaped
feature that can develop at the temporal (lateral)
border of disc (it rarely occurs at the nasal border) of
myopic eyes. It is primarily caused by atrophic changes
• Tesselated fundus: hypoplasia of RPE allowing
choroidal vessels to be seen

21. • Examine retina peripherally, ask patient to see in
all gazes and systematically examine the retina
with a moderate wide beam of light
• * when patient sees up ,position the
opthalmoscope below the slightly below the
pupil and aim the beam upwards toward the
superior retina
• Direct abnormalities can be missed with high
magnification and narrow FOV
• Finally evaluate the macula

22. Fundus examination with +90D
• Previously it was done with +60D but slit lamp
should be racked far which is not comfortable to
focus
• +90d came in to use later
• After anterior chamber angle estimation, dilation
is carried out.
• The patient is seated on biomicroscope and
observation system is adjusted so that anterior
segment of eye is obtained.
• Illumination should at an angle of 5* from
direction of motion of microscope, taking care
the light source does not occlude the microscope
oculars

23. • Patient instructed to look straight with beam wide
of 2-3mm is centered on patients pupil.
• Condensing lens is held with the help of index and
thumb finger of the left hand while examining
patients right eye
• And right hand while patients left eye
• The index finger should about 1 cm behind the
lens allowing the tip of finger to rest on patients
brow.

24. • While looking outside of microscope the slit lamp
beam is focused sharply on the surface of lens
• Slowly move the microscope away from patient until
aerial image of fundus is in focus
• once if it is focused any magnification of slit lamp
• While lens is held steadily, posterior fundus is scanned
by moving joystick.
• Peripheral fundus can be examined by instructing the
patient to see in different gaze and adjusting slit lamp
to focus.
• Viterous can be examined by racking the slitlamp
backward lightly