This document provides guidance on examining the eye using a slit lamp and diagnosing common eye conditions: 1. It outlines the basic components and use of a slit lamp, including adjusting the illumination, magnification, and focusing the microscope. 2. Examination techniques are described, such as assessing the depth of corneal lesions using a thin beam of light and grading anterior chamber cells. 3. Common troubleshooting issues for the slit lamp are addressed, such as inability to turn it on or difficulty focusing. Guidance is provided on systematic examination of the eye and techniques like staining the cornea with fluorescein.

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
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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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