scleral lens essentials - hoaecc.org
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Scleral Lens EssentialsDisclosures:
AlconBausch + LombContamacCooperVisionJohnson & JohnsonSpecialEyesValley Contax
Matthew J. Lampa, OD, [email protected]
Scleral Lenses
WhichLens
Modality???
Bausch + Lomb
Some eyes can not be optimally
fitted with corneal lenses
Because they result in
fluorescene patterns that look like this!
Is There a Way to Predetermine the Success of a Corneal GP Lens?
To Avoid This
Curvature versus Elevation
Axial DisplayPower Map
Elevation MapHeight Map
Axial Display Elevation Display
Corneal Elevation Differences and the Initial Selection of Corneal and Scleral Contact Lens
Frank Zheng OD, Patrick Caroline FAAO, Randy Kojima FAAO, Beth Kinoshita OD FAAO, Mark Andre FAAO, Matthew Lampa OD FAAO
Pacific University College of Optometry, Forest Grove, Oregon
Elevation Display
Map
Highest
Lowest
-227 um
+248 um
475microns
Less than 350um Greater than 350um
Patients with 350um or less of corneal elevation difference (along the greatest meridian of change) have an 88.2%
chance of success with a corneal GP lens.
N = 87 Patients127 CL Fits
-276um
+379um
+379- 276655
MicronHeight Differential
Patient CB Right Eye
Elevation Map
Patient VY Post Hydrops
Elevation Map
-260um
+430um-200um
Elevation: +430
Depression: -260
Differential = 690um
KeratometryPhotokeratoscopy
Videokeratography
Composite Corneal Topography
3.0 mm 8.0 mm 10.0 mm12.0 mm
Instrument Evolution
KeratometryPhotokeratoscopy
Videokeratography
Composite Corneal Topography
3.0 mm 8.0 mm 10.0 mm12.0 mm
Eaglet
20.0 mm
sMap 3D
22.0 mm
OCT
16.0 mm
Possible Scleral Lens IndicationsIrregular Astigmatism• Keratoconus• Pellucid Marginal Degeneration• Post Corneal Trauma • Post keratoplasty• Post K-Pro • Post Refractive Surgery
RK, PRK and LASIK• Post HSV and HZV• Athletes• GP stability (rocking) issues
Pathologic Ocular Surface Disease • Chemical Burns• Ocular Pemphigoid • Stevens-Johnson Syndrome• Symblepharon formation• Graft vs Host Disease• Persistent Epithelial Defect• Exposure Keratitis• Neurotrophic Keratopathy• Severe Dry Eye
– Sjogren’s Syndrome,– Filamentary Keratitis– Limbal Stem Cell Deficiency
•)
Scleral Lens
Indications
Ocular Surface Disease
Corneal Irregularity Ectasia/Scar/Post Surgery
Ocular Surface Disease…
Pre-Scleral 2 Months Post Scleral
SJS 20/4006 months
Post Scleral Lens 20/25
The Re-Birth of Scleral LensesHigh DK (100 DK+)GP lens materialsComputer assisted manufacturing techniques
Advanced in our understanding of scleral shape
Increasing knowledge related to the management of unique scleral lens complications
Average 8.5
High DK Scleral Materials• Menicon Z DK = 163• B & L, Boston XO2 DK = 141• Contamac, Optimum Extreme DK = 125• B & L, Boston XO DK = 100• Paragon HDS 100 DK = 100• Contamac, Optimum Extra DK = 100• Lagado, Tyro -97 DK = 97
Traditional Corneal / Scleral Shape
Scleral ShapeNew Understandings
Scleral Angle Measured at 15.0 & 20.0 mm
15.0 mm
20.0 mm
Tina Graff, Eef van der Worp, Patrick Caroline, Randy Kojima
Corneal/Scleral Angle 10 to 15 mm
10.0 mm 15.0 mm
Tina Graff, Eef van der Worp, Patrick Caroline, Randy Kojima
Average Angle from 10 to 15mm
T N
Scleral Angles at 15.0 & 20.0 mm
15.0 mm20.0 mm
Tina Graff, Eef van der Worp, Patrick Caroline, Randy Kojima, Mark Andre
Average Angle from 15 to 20mm
T N
Cone Angle Circa 1948Klaus Pfortner
Argentina
Corneal Vaulting Properties Of
Scleral Lenses
Scleral Lens Fitting Objectives
1. Central Vault Zone (250 to 400 microns)
2. Peripheral Lift Zone
3. Limbal Lift Zone
4. Scleral LandingZone
12 34 23 4
Anatomy of a Scleral Lens
Scleral LensFitting by Sagittal Height
3,800 4,000 4,200 4,400 4,800
Zone #1, Central Clearance Zone (CCC)
What is the Appropriate Central Corneal Clearance???
Central Clearance Zone300 to 400 microns of Apical Clearance
Apical Clearance at Dispensing250 microns
Apical Clearance Post 8 Hours150 microns
Tear Lens300 microns
CL Thickness0.35 mm
350 microns
Scleral Lens Setteling
Apical Clearance at Dispensing 410 um
Apical Clearance at 30 Days 270 um140 um of Lens Settling
AB 130 um Left ChangeEye 8 hours
Baseline400 um
8 Hours270 um (130 um)
30 mts.
1 hr.340 um (60 um)
2 hr.
4 hr.
6 hr.
Estimating Tear Film Thickness
Scleral Lens Corneal Settling11 subjects, 22 eyes
At lens application and 8 hours post lens wear
• Average apical clearance on application: 393um
• Average apical clearance after 8 hours: 265um
• Average drop in sag between insertion and 8hours (22 eyes): 127um
Lens Settling 15 Subjects• 96 microns following 8 hours of lens
wear.• 70 to 180 micron range. • 146 microns following one month.
Right Axial Left Axial
Right Elevation Left Elevation
SCLSCL
-3.50 DS
Excessive Apical
Clearance
OK?Not OK?
300 um 600um
Zone #2, Peripheral Corneal Clearance Zone (PCCZ)
Peripheral Cornea and
Limbal Clearance
PCCZ Bearing
AdequateClearance
Appropriate Limbal Clearance
Inadequate Limbal Clearance
Inadequate Peripheral Corneal Clearance
Dispensing 4 hrs. Post Dispensing
Diagnostic Lens Final Lens
Changing the PCCZ Peripheral Corneal Clearance Zone
Plus changes (+) = more depth
Minus changes (-) = less depth
1 degree steps = 25 microns sag change
Temporal Nasal
Temporal Nasal
Left Eye
Zone #3, Limbal Clearance Zone (LCZ)
White Light Cobalt Light
Limbus
Limbal Clearance Zone
StandardLimbal Clearance Zone
+5 Degree In the Limbal Clearance Zone
Changing the LCZ Limbal Clearance Zone
Plus changes (+) = more depth
Minus changes (-) = less depth
1 degree steps = 25 microns sag change
Bulging Graft
42.3 Sag 5,330 47.7
Horizontal Meridian
Keratoglobus
50.5 Sag 5,690 49.4
Zone #4, Scleral Landing Zone (SLZ)
Scleral Landing Zone Evaluation
Dispensing
Post 4 hours
Standard Edge Greater Lift Design
Conjunctivial “Compression”
Scleral Lens Fitting by Sagittal Height
Lens Application
Preservative-free salineand sodium fluorescein
Lens ApplicationThe patient looks down….they hold their lower
lid…practitioner the upper & the lens is applied.
Preservative Free Saline Options (in the USA)
The unit dosed 5 or 10 ml Inhalation PF saline.... 0.9% Sodium Chloride Solution by Rx only
The 12 OZ aerosol saline… Simply Saline by Arm and Hammer OTC
The 4 OZ bottle Purilens Plus Ultra PF Saline from Purilens OTC
LacriPure Saline from Menicon
Application Bubble
Re-Application
Apical Clearance = 350 microns
Conjunctivial Blood
Vessels
Over-refraction