ICD*

From - £136.58

The next generation mini-scleral lens for patients with diseased, asymmetrical and post-surgical eyes. The ICD family of designs employ a unique series of tangent zones, as opposed to curved surfaces, to create optimal fit and comfort for even the most challenging eyes.

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When to use

For patients who suffer with:

  • Bulging corneal transplants
  • Corneal transplants
  • Keratoconus
  • Kerato-globus
  • Pellucid marginal degeneration
  • Post refractive surgery
  • Normal shaped corneas
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Parameters

Material

 Paragon HDS 100

Dk100
BasecurveNA
Power+20.00 to -20.00
Diameters16.50, 14.50
Fitting set26 lenses – 14 @ 16.5mm, 6 @ 16.5mm Toric, 6 @ 14.5mm

 

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Fitting Guide

ICD is available in the following standard diameters:
  • 16.5 – For highly irregular or diseased eyes or when the px HVID is greater than 11.00mm.
  • 14.5 – For when the patient has a more regular eye shape, a small HVID (less than 11.00mm) or a small aperture
  • 16.5 Toric – For patients with astigmatic eyes or a toric sclera
Initial fitting lens selection
  • For normal depth eyes, post-refractive surgery or ocular surface disease with HVID of 11.5 or greater use the 16.5 diameter with a 4200 sag, if the HVID is less then start off with a 14.5 diameter 3400 sag.
  • With median depth eyes such as moderate keratoconus, pellucid marginal degeneration or low depth corneal grafts start off with the 4500 sag in the 16.5 or the 3700 in the 14.5.
  • If the patient has a high depth corneal graft or very advanced keratoconus the 16.5 lens with a sag of 4800 should be the starting lens, even if the HVID is less than 11.5, the larger diameter is needed to clear the cornea fully.
Ideal Clearance
  • On initial insertion aim for approximately 300 microns of clearance, the fluid layer and lens thickness should be approximately the same.
  • The fluid layer thickness allows for settling back to occur which will reduce the clearance over time.
  • After settling back has occurred the clearance should be approximately 150 – 200 microns.
  • Use a slit lamp with optic section or anterior OCT to check clearance values.
  • If there is touch then increase the sag of the diagnostic lens until no touch is observed. If the clearance exceeds 300 microns then reduce the sag until the excessive clearance is reduced.
Central Clearance Zone (CCZ)
  • The diagnostic lens should completely vault the central cornea.
  • Fit higher or lower sagittal depth diagnostic lenses to increase or decrease the central corneal clearance.
Limbal Clearance Zone (LCZ)
  • The diagnostic lens should completely vault the limbus. To observe clearance in this area, use white light to assess the fluorescein through the limbus and out to the sclera.
  • Order a modified LCZ if the peripheral cornea and/or limbal depth is inadequate.
  • Increase the LCZ in 25 micron steps if the limbal clearance is insufficient. Five steps which equals 125 microns is normally the minimum adjustment.
Scleral Landing Zone (SLZ)
  • Ensure fluorescein is evident throughout the limbus and around 100% of the visible limbal region.
  • The ideal peripheral alignment /bearing of the lens can also be noted by the absence of fluorescein near the edge.
  • The diagnostic lens should land with all of its weight on the sclera.
  • View the SLZ to determine if there is excessive edge lift or excessive tightening or blanching. Order a modified SLZ if edge changes are necessary.
  • Make adjustments based on: Mildly tight SLZ -1, Moderately tight SLZ -2, very tight SLZ -3. Please note every 1 degree of change alters the sag and therefore the clearance by 25 microns.
Refraction
  • Perform a spherical over-refraction where possible, if there is a residual cylinder which improves the patient’s vision then use a toric trial lens and note the position of the flat markings as well as the required astigmatic axis.
Ordering
  • To order the lens the following are required, the diameter and sag of the lens, any adjustments to the CCZ, LCZ and SLZ, the power of the lens cylinder axis if the lens needs to be toric and the position of the rotation markers.