Dark Room Procedures for undergraduates(MB,BS) in the field of Ophthalmology are explained in simple terms in this presentation. Series of lectures taken at Central Park Medical College Lahore Pakistan.

1. The
Reflection

2. Dark Room Tests
Dr. Zia-Ul-Mazhry
FCPS(Pak),
FRCS(Edin),
FRCS(Glasgow),
CIC Ophth- (UK)
Assistant Professor
Central Park Medical college Lahore
Consultant Eye Surgeon &
Head of Department
WAPDA Teaching Hospital Complex Lahore.

3. Dark room Tests
• Oblique Illumination
• Distant Direct Ophthalmoscopy
• Direct Ophthalmoscopy
• Retinoscopy
• Indirect Ophthalmoscopy
– Indirect Ophthalmoscope
– Slit Lamp Biomicroscopy

4. Oblique Illumination
• Objective
– Examination of External and
anterior Segment structures
• Instruments
– Illumination Beam
– Magnification Aid/Microscope
• Method
– Illumination beam at 45 degrees

5. Slit Lamp
• The slit-lamp
is a low-
power
microscope
combined
with a high-
intensity light
source that
can be
focused to
shine in a
thin beam.

6. SLE
• Observation by optical
section
• Direct diffuse
illumination
• Indirect illumination
• Retro-illumination
• Scattering sclero-
corneal illumination
• Fundus observation
and gonioscopy with
the slit lamp

7. SLE
• The slit lamp exam uses an
instrument that provides a
magnified, three-dimensional (3-D)
view of the different parts of the eye.
During the exam, your doctor can
look at the front parts of the eye,
including the clear, outer covering
(cornea), the lens, the colored part
(iris), and the front section of the
gel-like fluid (vitreous gel) that fills
the large space in the middle of
the eye.
• Special lenses can be placed
between the slit lamp and the
cornea (or directly on the cornea) to
view deeper structures of the eye,
such as the optic nerve, retina, and
the area where fluid drains out of
the eye (drainage angle ). A camera
may be attached to the slit lamp to

8. Distant Direct
Ophthalmoscopy
• Objective
– To Examine and classify media
opacities against fundal glow
• Instrumentation
– Direct Ophthalmoscope
• Methods
– Throw the light with DO at half
meter distance
– Parallax Method of deviation

9. Distant Direct
Ophthalmoscopy
• Parallax Method of deviation
– Ask the patient to move his/her
eye
– Opacities Moving
• With
– Anterior to nodal point
• No movement
– At or very near to nodal point
• Against Movement
– Behind the nodal point

10. Distant Direct
Ophthalmoscopy
• Viewing ocular
media
– Observe red reflex
– Look for media
opacities
• Cataracts
• Corneal scars
• Large floaters

11. Direct Ophthalmoscopy
• Objective
– To examine the retina/fundus
• Instrumentations
– Direct ophthalmoacope
• Methods

12. Fundoscopy
• Fundoscopy is
the assessment
of the fundus
using an
ophthalmoscope

13. Examination Technique
• dim the lights.
• ask the
patient to
fixate on a
distant target.
• approach the
patient from
the side.
• examine the
optic nerve
and
surrounding
retina.

14. Fundoscopy-Video

16. Direct Ophthalmoscopy:
Basic skills
• Proper position for
central fundus
viewing
• Right eye to right
eye
• Left eye to left eye
• Don’t rub noses…

17. Direct Ophthalmoscopy:
Basic skills
• Proper position for
peripheral fundus
viewing

18. Direct Ophthalmoscopy:
Exam technique
• Be systematic
• Start at optic disc & work
radially
• Observe:
– Optic disc: C/D ratio
– Vessels: course & caliber, AV
ratio, light reflex,
crossings/banking
– Macula
– Peripheral fundus

19. Direct Ophthalmoscopy:
Basic skills
• Clinical pearls
– FOV incr. when closer to Pt.
– Larger pupil increases FOV
– Contact lenses
– Check lens wheel– watch
accommodation

20. Indirect
Ophthalmoscopy
• Objective
– Fundus Examination
• Instrumentation
– Indirect Ophthalmoscope
– Condensing Lens
• Methods

21. Funduscopy
Techniques/instruments
• Direct Ophthalmoscopy
• Indirect Ophthalmoscopy
• Fundus Biomicroscopy
• Fundus Contact Lens

22. Why do we dilate
pupils?

23. Direct Ophthalmoscopy
• Advantages
– Portable
– Easy to use
– Upright image
– Magnification 15x
– Can use w/o dilation
• Disadvantages
– Small field of view
– Lack of stereopsis
– Media opacities can
degrade image

24. Indirect Ophthalmoscopy
• Monocular or binocular
• Advantages:
– Wide field of view
– Binocular instruments
provide stereopsis
• Disadvantages:
– Requires more skill
– Decreased magnification
(3x)
– Requires dilation
– Inverted image

25. Indirect
Ophthalmoscopy

26. Fundus Biomicroscopy
• Field of View & Mag:
– FOV <indirect but
>direct
– varies w/lens & slit
lamp mag
• Inverted image
• Stereopsis
• Dilated pupil
• Requires skill

27. Fundus Biomicroscopy

28. Fundus Contact Lens
• Requires physical
contact w/eye
• Viewed
w/Biomicroscope
• Advanced dx &
surgery
• Field of view &
Mag vary w/lens
design

29. Direct Ophthalmoscopy:
Basic skills
• Optics:
– Illumination system
– Magnifier
• Hyperopes
• myopes
– Observation system
• Lens wheel
• Apertures

30. Normal Fundus

31. Viewing the Optic
Nerve Head
• Observe:
– Size
– Shape
– Color
– Margins
– Cup to disc ratio (C/D) horiz &
Vert

32. Blood Vessel
Evaluation
• Observe:
– Vessel diameter
– Shape/tortuosity
– Color
– Crossings
– Light reflex
– Artery/Vein (A/V) ratio: after 2nd
bifurcation

33. Hypertensive
Retinopathy
• Scheie classification:
I: Thinning of retinal arterioles
relative to veins
II: Obvious arteriolar narrowing
w/focal areas of attenuation
III: Stage II + cotton wool spots,
exudates & hemes
IV: Stage III + swollen optic disk
(similar to papilledema)

34. Vessel “Crossings”
• Normal crossing
Direction change
“banking’” or “nipping”

35. Arteriolosclerosis
• Increased light reflex (1/2)
• “Copper wire” arterioles
• “Silver wiring” arterioles
– whitish appearance
w/continuing sclerosis
• Increased A/V crossings

36. Macula
• Lies about 2DD (disc
diameters) temporal to the
optic disc
• Should be avascular
• May appear darker red than
surrounding retina
• Should see bright foveal reflex
on younger pts

37. The Indirect Ophthalmoscope
George T. Timberlake, Ph.D.
Department of Ophthalmology
University of Kansas Medical Center
Gullstrand Indirect
Ophthalmoscope
ca. 1910

38. Allvar Gullstrand
1862 - 1930
Professor of Physical &
Physiological Optics,
University of Uppsala
First “reflex free”
ophthamoscope
Nobel Prize 1911 for
work on optics of eye
Swedish Ophthalmologist
GTT 04

39. Gullstrand Principle
for Reflex-free Ophthalmoscopy
Light entrance and exit separated in pupil plane
Light entering eye
Light leaving eye Pupil
GTT 04

40. Retinoscopy
• Objective
– To determine refractve status of
the eye
• Instrumentation
– Retinoscope
– Trial Lens set
– Trial frame

41. Retinoscopy
• Methods
– Ask the patient to fixate on a
distant target
– Half to 1 meter distance
– Project the streak on pupil
– Move the streak and observe the
movement of red reflex

42. Retinoscopy
• Moves with
– Emetropia
– Hyperopia
– Myopia of less than 1 diopter
• No Movement
– Myopia of exactly 1 diaopter
• Moves against
– Myopia of more than 1 diopter

43. Retinoscopy
• Insert +1 D Lens in front of the
eye while working at 1 meter
– No movement
• Emetropia
– With movement
• Hyperopia
– Against movement
• Myopia of < 1 D

44. RETINOSCOPE
Welch Allyn Neitz

45. RETINOSCOPE
Sight hole
Polarizing
filter
External intergrated
Streak rotator
And focusing
sleeve

46. RETINOSCOPE
Sight hole
External focusing
Sleeve
Streak rotator
rheostat

47. RETINOSCOPE
BASIC CONCEPT
1) EMMETROPIA
• Light emerge Parallel
2) HYPEROPIA
• Light emerge Diverge
3) MYOPIA
• Light emerge
Converge

48. RETINOSCOPE
EMMETROPIA
Parallel

49. RETINOSCOPE
HYPEROPIA
Diverge

50. RETINOSCOPE
MYOPIA
converge

51. RETINOSCOPE
THE STREAK LIGHT REFLEX
CONCEPT
1) Break Phenomenon
2) Thickness Phenomenon
3) Skew Phenomenon
4) Movement Phenomenon

52. RETINOSCOPE
• BREAK PHENOMENON
Iris pupil Streak light light reflex
No Break Break

53. RETINOSCOPE
• THICKNESS PHENOMENON
Same thickness Different thickness

54. RETINOSCOPE
• SKEW PHENOMENON
light reflex movement streak movement
No skewness Skew

55. RETINOSCOPE
• MOVEMENT PHENOMENON
With movement Against movement

56. RETINOSCOPE
• NEUTRALITY
- pupil fills
- no movement

57. RETINOSCOPE
• With movements
– Hyperope
– Neutralize with Plus lenses
(convex lenses)
• Against movements
– Myope
– Neutralize with Negative lenses
(concave lenses)

58. RETINOSCOPE
• Working Distance Lenses
– Purpose : Light emerge from Pt
eye conjugate with examiner’s
retina
• +1.50 D - @ 66.7cm
• +2.00 D - @ 50.0cm

59. Retinoscopy Video

60. The
Reflection

61. • Thank you