Basic Clinical Consideration for Scleral Lens Fitting

Dave Kading, O.D., F.A.A.O.

Summary

This workshop will introduce the attendee to scleral lenses, its uses, and the fitting strategies proven to optimize success. A specific focus will be on optimizing the fit of the lenses when appropriate candidates are selected. Hands on experience with a variety of lenses will provide the attendee a high level of confidence fitting the lens

Learning Objectives:

1)Understand those patients most appropriate for scleral lenses

2)Discuss successful fitting strategies to optimize fitting characteristics

3)Understand the care of these lenses and the steps needed to optimize success

Course Outline (1 hour)

1)Understand conditions that would warrant scleral lenses

  1. Corneal ectasias
  2. Keratoconus
  3. Pellucid Marginal degeneraton
  4. Corneal trauma
  5. Penetrating keratoplasty
  6. Severe ocular surface disease
  7. Dry Eye
  8. Persistent epithelial defects
  9. High ametropia
  10. Astigmatic patients

2)When do you consider scleral lenses

  1. Other options may not of adequately corrected problems
  2. Visual
  3. Have usually tried soft lenses but vision was compromised
  4. May have tried gas permeable (GP) lenses but there issues with comfort
  5. Ocular surface
  6. May have tried traditional treatments – topical medications
  7. May have tried and failed with soft contact lenses

3)Discuss handling and care of lenses

  1. Multipurpose solution – similar to traditional GP lenses
  2. Conditioning solutions
  3. Cleaners
  4. All in one systems
  5. Peroxide solution
  6. Preservative free saline
  7. Necessary that the bowl of the lens is free of preservatives
  8. Must be rinsed free of preservatives after storage
  9. Bowl of lens is then filled with non-preserved saline
  10. Lens insertion
  11. Bowl of lens must be completely filled with saline
  12. Two to three fingers need to be utilized to balance the lens
  13. Modified large DMV for balance
  14. Patients head should be parallel to the ground
  15. Lens is then placed directly over the cornea
  16. Lens removal
  17. Place DMV on the lower third of the lens to remove

4)Understand the fitting process

  1. Understanding initial lens selection
  2. Sagittal depth
  3. Increased with greater irregularity
  4. Greater sagittal depth with steeper base curve or larger lenses
  5. Central clearance
  6. Ideal is between 100-300um
  7. Low clearance
  8. Requires increased sagittal depth
  9. Steepen base curve
  10. Steepen limbal clearance
  11. Excessive clearance
  12. Requires decreased sagittal depth
  13. Flatten base curve
  14. Flatten (decrease) limbal clearance
  15. Limbal clearance
  16. Low clearance
  17. Increase sagittal depth
  18. Steepen limbal curve
  19. Excessive clearance
  20. Decrease sagittal depth
  21. Flatten limbal curve
  22. Scleral landing
  23. Alignment
  24. Impingement
  25. Excessive pressure at the edge of the lens on the conjunctiva
  26. May cause vascular blanching
  27. Requires scleral landing flattening
  28. Compression
  29. Excessive pressure at the most central portion of the scleral landing zone
  30. May cause vascular blanching at the transition between the limbal clearance zone and scleral landing zone
  31. Requires scleral landing steepening

5)Clinical considerations

  1. Independent zone manipulation
  2. Each zone discussed previously can be manipulated independent of one another
  3. Fitting lenses on a toric sclera
  4. Discussion of toric scleral landing zones in order to fit over toric scleral
  5. Fitting lenses in the presence of pinquecula
  6. Discussion of notching the scleral landing zone

6)Fitting workshop (2 hours)

  1. Practice lens insertion
  2. Practice lens removal
  3. Assess lens fits
  4. Understand how changing parameters alters the fit of the lenses