Practitioner Learning Curve in Fitting Scleral Lenses in Irregular and Regular Corneas Using a Fitting Trial

Table 1

Characteristics of the mini- and full-scleral lenses trial sets used in the present study.

Parameter	Mini-scleral lens	Full-scleral lens
Material	Boston XO; (hexafocon A)	Boston Equalens II; (oprifocon A)
Dk (ISO/Fatt)	100	85
Central Thickness (-3.00 D)	0.25 mm	0.45 mm
Diameter	From 15.20 to 18.00 mm in 0.40 mm steps	From 18.00 to 24.50 mm in 0.50 mm steps
Back Optic Radius	8.20 mm; (from 7.00 to 9.40 mm in 0.20 steps)	From 7.20 mm to 9.80 mm in 0.10 mm steps
Power	Sphere +20.00 D to -25.00 D in steps of 0.25 D; Front cyl -0.50D to -3.00D in steps of 0.25D; Axis 0 to 180 degrees in steps of 1 degree	Sphere +30.00 D to -30.00 D in steps of 0.25 D; Front cyl -0.50D to -3.00D in steps of 0.25D; Axis 0 to 180 degrees in steps of 1 degree
Refractive Index	1.415	1.423
Hardness	81/112 (Shore/ Rockwell)	114 (Rockwell)
Density	1.27	1.24
Contact Angle (deg.)	49	30
Sagittal height	From 0.25 to 6.75 in 0.25 steps	From 2.47 to 5.07 in 0.10 steps
Peri-Factor / Sclera Opening	From -8 to +8 in steps of 1	From 11.50 to 17.25 in 0.25 steps
Toricity (difference in peri-factor)	From 1 to 6 in steps of 1	From 1 to 4 in steps of 1