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45b. EyeSpace Scleral 1 Quick Start Guide (not published)

11. EyeSpace ScleralCharl Laas

The following guide outlines how to fit the EyeSpace scleral. For advanced fitting see the attached "Advanced Scleral fitting guide"

There are five steps to fitting the EyeSpace Scleral:

Step 1 - Lens Diameter

The EyeSpace Scleral is available in two diameters, 16.50 mm and 17.50 mm:

  • Corneal HVID < 11.50 mm use lens diameter 16.50 mm
  • Corneal HVID =>11.50 mm use lens diameter 17.50 mm
  • Corneal HVID => 12.40 mm use lens diameter 18.50 mm

Step 2 - Lens Sag

EyeSpace Scleral lenses should be fitted with a sagittal height, 300 microns more than the sagittal height of the cornea at the 15.00 mm chord. One of the three methods listed below can be used to determine the sagittal height of the EyeSpace Scleral diagnostic lens.

Method 1: Smith Technique Use the Smith technique to determine the corneal sagittal height. This is described in the video below.

Smith Technique from EyeSpace on Vimeo.

Add another 300 microns to the value to calculate the starting EyeSpace Scleral diagnostic lens sagittal height.

Corneal Condition Sagittal Height Table


Method 2: Medmont Weighted Ave

Add 2000 microns to the Medmont Weighted Ave at 10.00 mm.
Add another 300 microns to calculate the starting EyeSpace Scleral diagnostic lens sagittal height.

Method 3. Using the EyeSpace Scleral Wizard
Scleral wizard quick start guide from EyeSpace on Vimeo.

  • Place the suggested diagnostic lens on the eye and evaluate the Post Lens Tear thickness (PLTT) using your slit lamp or OCT.
  • Increase or decrease the diagnostic lens sagittal value to reach a PLTT of 300 microns (same thickness as the lens).
  • Then let the lens settle for 30 min.
  • After the diagnostic lens has settled on the sclera, the observed PLTT should be 150 microns (half the lens thickness).
  • Should the PLTT not be 150 microns choose an alternative EyeSpace Scleral diagnostic lens to increase or decrease the lens sagittal value until the PLTT shows a 150 microns clearance.

Step 3

Back Optic Zone Radius

The EyeSpace Scleral diagnostic lenses have a predetermined Back Optic Zone Radius (BOZR). In advanced cases, it may be necessary to change the BOZR value to more closely align with the corneal shape. Review the advanced scleral guide for more information.

Step 4

Scleral Landing Zone

The Scleral Landing Zone (SLZ) should align evenly on the scleral in all 360-degree meridians. The SLZ can be specified as one of the following:

  • Extra Increased Steep
  • Increased Steep
  • Steep
  • Standar
  • Flat
  • Increased Flat
  • Extra Increased Flat

Judge the alignment of the SLZ using one of the diagnostic scleral trial lenses and choose the SLZ the best aligns with the scleral angle. The fit of the SLZ can be assessed as follows:

Very Flat

Fluting, heavy blanching at the limbus and a blue appearance of the limbus.

To correct the fit, steepen the SLZ by two steps.

Flat

Light blanching at the limbus.

To correct the fit, steepen the SLZ by one step.

Aligned

Even landing on the sclera and no blanching at limbus or lens edge.

The SLZ is correct, and no adjustments are necessary.

Tight

Light blanching at the lens edge.

To correct the fit, flatten the SLZ by one step.

Very tight

Heavy blanching at the lens edge and scleral indentation.

To correct the fit, flatten the SLZ by two steps.

Step 5

Back Vertex Power

Perform an over-refraction of the scleral lens on the eye. Calculate the final back vertex power of the scleral lens in the air by adding the vertex over-refraction power to the diagnostic lens power.

Step 6

Ordering

The correct format to order the EyeSpace scleral lens is to specify the parameters as follows:

Lens Type / BOZR / Diameter / Lens Sag / SLZ / BVP / Lens colour

For example:

OD: EyeSpace Scleral Toric / 7.50 / 17.50 mm / 4300 x 4500 / Standard x Steep / -2.50D / Clear

https://eyespace.freshdesk.com/helpdesk/attachments/8006596082