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:
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.
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.
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.
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:
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:
Fluting, heavy blanching at the limbus and a blue appearance of the limbus.
To correct the fit, steepen the SLZ by two steps.
Light blanching at the limbus.
To correct the fit, steepen the SLZ by one step.
Even landing on the sclera and no blanching at limbus or lens edge.
The SLZ is correct, and no adjustments are necessary.
Light blanching at the lens edge.
To correct the fit, flatten the SLZ by one step.
Heavy blanching at the lens edge and scleral indentation.
To correct the fit, flatten the SLZ by two steps.
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.
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
OD: EyeSpace Scleral Toric / 7.50 / 17.50 mm / 4300 x 4500 / Standard x Steep / -2.50D / Clear