ADVANCES IN SCLERAL LENS TECHNOLOGY
ALEX GIBBERMAN, OD, FAAO, FSLS 2020 EYECARE, LOVELAND, OHIO A BRIEF HISTORY OF THE WORLD…OF SCLERALS
16th century- Da Vinci concepts. Blown glass shell. No power.
1887-Muller brothers. Thinner blown glass shells
1888- Adolf Fick. Glass lenses first to treat k conus with correction. First to note corneal edema
1889- Dr. Kirstein is born! Also August Muller is first to use scleral to correct for high myopia HISTORY CONTINUED…
1890’s- The use of saline with scleral insertion is introduced
1912- Zeiss makes first diagnostic fitting set
Also notable in 1912, Dr Zelczak is born!
1957-PMMA sclerals introduced.
1970s-John James Little and Arthur Irving first to use RGP sclerals
1983-RGP scleral materials updated by optometrist Don Ezekiel MODERN SCLERALS
Between the mid 1980s and now, significant material and dk improvements have occurred.
Late 1980s- Back toric optics were introduced to sclerals
1992- the first impression based, computer scanned and created lens was made in the UK
2013-EyePrintPro was developed to take an impression and match exact contour of the eye
Current- multifocal optics, decentered optics, front toric and back toric optics, prism and higher order aberration correction are all possible
Scleral topographers: Getting us closer to empirical fitting. We will discuss in more detail SPECIFICATIONS OF A MODERN SCLERAL LENS?
Here is just one example
Base Curve 7.50 Diameter 16.1 mm Sagittal Depth: 3500um Toric Peripheral curve, flatten horizontal meridian 100um steepen vertical meridian 200um Front toric overall power -400 -125 x 105 Multifocal Center ADD 2.5mm Zone +250 ADD Nasal microvault or notch to avoid pinguecula Material: Optimum Infinite Dk 200 needs hydropeg coating WHAT A CURRENT SCLERAL LOOKS LIKE
SCLERAL TOPOGRAPHERS
Eaglet- Eye surface profiler
Pentacam- CSP
Visionary Optics-Smap3D Latitude Focal Points
Focal Points will allow the import of multiple types of scleral topography files such as Eaglet ESP, Pentacam CSP and sMap.
Importing the scleral topography allows the use of Focal Points CAD system to design and overlay a lens in virtual Imported Scleral Topography Scleral Lens Model reality prior to fitting on the patient. EYE SHAPE (WITH IRREGULAR CORNEAS)
Study from Greg Denaeyer et al (rounded numbers) 5% spherical 30% toric 65% irregular/quad specific SPHERICAL SCLERA TORIC SCLERA
SPHERICAL, QUAD SPECIFIC, IRREGULAR PINGUECULA AND A NOTCH IMPRESSION BASED EYE PRINT PRO Small studies and recent data show results similar to corneal data CONSIDERATIONS WHEN USING SCAN Conjunctive is soft and will take time to reform itself TECHNOLOGY Current data shows 3-5 days to return to normal Realistically, need to be out of sclerals for 3 days to get accurate profilometry/curvature DECENTERED OPTICS FOR MULTIFOCALS
Scleral lenses are almost never perfectly centered
Most people have flatter/more elevate nasal/temporal regions of scleral
Leads to Scleral that sits inferiorly or inferior nasal
the optical center of the lens is decentered on the contact lens
To become centered over the visual axis DECENTERED OPTICS
Laser marked trial lens system with degree markers
Record the degree with the MOST hashmarks inside the pupil
Most useful for Multifocals
SCLERAL LENS SHAPE ADVANCEMENTS
Optic zone 8-10mm Rx is on FRONT surface Spherical/toric/multifocal/decenter ed optics Transition zone/limbal zone MUST clear the limbus (unless using fenestrations but that is another topic) Sagittal height of lens is created here**** Can be made spherical or toric Haptic/landing zone Mainly concerned with BACK surface Spherical, toric, or quad specific Can include channels, notches, vaults etc VENTING CHANNELS FENESTRATIONS MATERIALS/COATING
Examples:
Optimum extra- the workhorse material for my sclerals dk 100 Optimum extreme- higher dk of 125 Optimum infinite- dk of 200
Keep in mind that higher dk lenses are great for oxygen and corneal health BUT need to be coated with Hydrapeg because wettability becomes an issue. Tyro 95