Dr Carmel Crock RVEEH Melbourne, explains basics of slit lamp use

1. Eye Emergencies
Dr Carmel Crock FACEM
Director, Emergency Department, RVEEH
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2. 2

3. Cornea
• 5 layers
• Depth
0.5-0.8mm
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4. 4

5. Normal Cup/Disc ratio 0.3
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6. Normal retina
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7. Optic disc swelling
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8. Malignant hypertensive retinopathy.
Grosso A et al. Br J Ophthalmol 2005;89:1646-1654
©2005 by BMJ Publishing Group Ltd.

9. Anatomy of a Slit Lamp
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10. Features
• Illumination
system
• Magnification
via binocular
microscope
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11. Basic Components: illumination
• Bulb
• Filters
• Slit height
control
• Slit rotator
• Mirror
• Slit width
control
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12. Height
Filters Filters
&
1.Unfiltered
Cobalt
blue 2. Heat
absorbing
1 2 3 4 3. 10%
Grey
5
4. Red free
5. Cobalt
blue 12

13. Width
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14. Basic Components: magnification
• Eye pieces
• Magnification changer
• Joy stick
• Lock
• Base carriage
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15. Magnification
Most slit lamps have:
• 2 objective settings (1 and 1.6)
• 2 eye piece options (10x and 16x)
• Total magnification ranges thus from 10x-
25x
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16. 16

17. Use of the Slit Lamp
• Seat patient
comfortably
• Adjust
table, chair
• Position
patient’s head
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18. 18

19. Focus the Microscope by
1. Adjusting
inter-puplillary
distance
2. Adjusting the
eye pieces
2 2 (set at 0 or
dial in your
refraction)
1
3. Checking
magnification
is on 1x
setting
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20. 3
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21. Focus Patient’s Eye
• Microscope straight
• Light column 20-30
degrees from side
• Microscope moves via
joystick
• Move laterally
• Move in and out
• Bimanual
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22. Adjust the Illumination
• Brightness: filters
• Width: slit vs broad
beam
• Height: long vs
pinpoint
• Cobalt blue
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23. Trouble Shooting:
unable to turn it on
• Check all connections
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24. Trouble Shooting:
power on - but no light
• Slit width closed
• Slit height too small
• Bulb burned out
• Bulb not positioned
correctly
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25. Trouble Shooting:
difficulty moving instrument
• Unlock
• Check patient position
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26. Trouble Shooting:
difficulty focusing
• Check eye-pieces
on correct setting
• Make sure
patient’s head in
correct position
• Adjust joy stick in
and out
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27. Trouble Shooting:
misalignment of slit and view
• Check magnification changer
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28. Anterior Segment Examination
• Systematic examination of the eye from
front to back
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29. no FB no FB Lashes/ Lids
Conjunctiva
Cornea
Sclera
Anterior chamber
-deep and quiet
Iris
Lens
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30. 30

31. 31

32. http://eyelearn.med.utoronto.ca/default.htm 32

33. Normal cornea
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34. Assessment of Depth
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http://eyelearn.med.utoronto.ca/default.htm

35. Oedematous thickened cornea from deeply embedded FB
Do not remove deep CFB
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36. Assessment of
Depth Corneal Lesion
• Thin beam of light
• Illumination column 35-45 degrees
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37. Stain Cornea
• Use fluorescein
(+/- do Seidel’s test)
Corneal abrasions
http://eyelearn.med.utoronto.ca/default.htm
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38. Fluorescein
• Absorbs light in blue wavelength
• Emits green fluorescence
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39. Tips - fluorescein
• Don’t forget to use it eg. HSV
• Measure size abrasion
• Total vs nil staining - chemical injury
• Fluorescein under lid – upper lid abrasion
• Seidel’s + or –ve -document
• Self sealing wounds
• Apply fluorescein then wait for bit to see
more subtle staining
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40. Measuring Size of Lesion
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41. Anterior Chamber
Setting up to look at anterior chamber
-darkened room
• 1mm beam height
• Bright intensity illumination
• High magnification
• Is the anterior chamber deep and quiet?
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42. Grading of AC Cells
(counted with 1x1 mm slit)
Activity Cells
+ 6-15
++ 16-25
+++ 26-50
SUN 2005 Am J Opthalmol 2005: 140: 509
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43. Removing a Foreign Body
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44. Removal of corneal foreign body with
needle and with burr

45. Step by step guide – how to use
slit lamp - summary
1. clean
2. practice turn on and using
3. bring in patient - adjust chin rest, lat.
canthus at line, forehead against band
4. prepare microscope - interpupillary
distance, oculars set at 0, low mag
5. prepare light - low volt, 10% grey, wide
beam
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46. Step by step guide – how to use
slit lamp - summary
6. Examine lids, lashes, conj, sclera, cornea,
iris, lens
7. Use narrow beam to examine corneal
lesion – measure depth
8. Set up to look at anterior chamber - depth,
cells, flare - bright/1mm beam/high mag
9. Use fluorescein –measure size lesion
10.Turn off and clean
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