Soft Lenses for Irregular Corneal Conditions

Soft Lenses for Irregular
Corneal Conditions
Lynette Johns, OD, FAAO
Jennifer McMahon, BOptom,
MCOptom
Financial Disclosures:
Jennifer McMahon, BOptom, MCOptom
• Clinical Consultant to Innovative Sclerals Ltd, UK
Lynette K. Johns, OD, FAAO, FSLS
• Paid clinical and education consultant to B+L
Custom Lab Channel Business
Soft Lenses for KC? Not a new Concept
• McTigue J, and Townsend W.
The use of a new soft lens in
irregular ectatic corneas: a
preliminary report.Tr. Am.
Ophth. Soc., vol. 69,1971
• Less harm to cornea
• Pliable material
• Make irregular surface more
regular
• 40 eyes (24 PKP 16 KC)
• 10 eyes 20/20, 26 eyes 20/2520/40; 4 < 20/40
Clinical Indications for KeraSoft® IC
and Large Diameter GP Lenses
• Natural Ectasia
• Keratoconus
• Keratoglobus
• Pellucid Marginal Degeneration
• Post-Refractive Surgery
• Post-LASIK Ectasia
• Post-Radial Keratotomy
• Post Penetrating Keratoplasty
• Contact Lens Intolerance
FLEXLENS® Tri-curve Keratoconus
• By X-Cel Contacts in Duluth, GA
• Mechanism of action: Increased center
thickness to mask irregularity
• Corrects irregular astigmatism with up to 2.00
D residual astigmatism
• If >2.00 D residual astigmatism then switch to
Flexlens® Piggyback design or Sphero-cyl
spectacles
• 10 Lens Diagnostic Set
FLEXLENS® Tri-curve Keratoconus Lens
Anatomy
• 3 posterior curves
• 15.0 DIA with 7.5 posterior optic zone
• 0.45 to 0.65 mm center thickness
FLEXLENS® Tri-curve Keratoconus
Parameters
FLEXLENS® Tri-curve Keratoconus
Fitting Process
• Select first diagnostic lens based on average K
• Check centration
• If decentered—too flat
• Push up test
• Once the lens is centered make sure it is mobile on push
up test
• Fit evaluation
• 1.0-1.5 mm limbal draping
• 0.5-1.0 mm movement
• Over-refract
NovaKone™
• By Alden Optical in Lancaster, NY
• Mechanism of correction: Increased center
thickness to mask corneal irregularity
• Corrects irregular astigmatism and residual
astigmatism
• Stabilized fit by proprietary Dual Elliptical
Stabilization™
• 18 Lens Diagnostic Set
NovaKone™ Anatomy
• A- central base curve
(average central K)
• B- Fit curve similar to
standard base curve
• C- Aspheric Anterior
surface and thin periphery
• D- Index of Thickness (IT)
factor
• E- Front surface toric
optics
• F- Dual Ellipitical
Stabilization™
NovaKone™ Parameters
NovaKone™ Fitting Process
• Determine average sim K and select recommended
diagnostic lens
• Use high molecular weight fluorescein to evaluate fit
and centration
• Ideal fit is light central touch
• Over-keratometry reading determines IT factor
• When mires are crisp IT is correct
• Over-refract and compensate for rotation
• Determine fitting curve to demonstrate 0.5-1.0 mm
movement.
NovaKone™ Fitting assessment
Soft lenses that mask irregularity with
center thickness
•HydroKone™ available from Visionary Optics
Front Royal, VA
•Soft K Toric available from Advanced Vision
Technologies Golden, CO, Accu-Lens Lakewood,
CO, and Soflex D.N. Misgav, Israel
•YamaKone™ IC available from GP Specialists
Ontario, CA
KeraSoft® IC
• Licensed by B+L, offered through Art Optical,
ABB Optical, Metro Optics, and TruForm
Optics
• Mechanism of Correction: Anterior Aspheric
Optics
• Uniform center thickness
• Prism Ballasted Stabilization
• 8 Lens Diagnostic Set
KeraSoft® IC Lens Anatomy
• Front surface aspheric
toric optics
• Modifiable periphery
relative to BC
• 2 sectors of
independent modifiable
peripheries
KeraSoft® IC Lens Parameters
KeraSoft® IC Fitting Process
Specialty Soft Lens Materials
Available
• 49% Hioxifilcon B
Dk=15
Flexlens
• 55% Methafilcon A
Dk=18
Flexlens,HydroKone
• 54% Hioxifilcon D
Dk=24
NovaKone, HydroKone
• 59% Hioxifilcon A
Dk=28
Flexlens
• 67% Xylofilcon A
Dk=29
Soft K
• 74% Efrofilcon A
Flexlens, KeraSoft, Yamakone
Dk=60
Why Soft Lenses?
•
•
•
•
•
Comfort
Ease of Handling
Lens Centration
Less Practitioner Intimidation
Diagnostic Fitting
Thank you for your attention!
[email protected]
Specialty Soft Lenses –
where do they fit in?
Jennifer McMahon
BOptom(Hons) MCOptom FBDO
Case study 1 (OP)
18 year old male
Diagnosis:
• Right eye - keratoconus
• Left eye - mild keratoconus
Case study 1 (OP)
18 year old male
Diagnosis:
• Right eye - keratoconus
• Left eye - keratoconus frustre
Social history:
• Student
• Active extra-curricular life in theatre
Case study 1 (OP)
18 year old male
Diagnosis:
• Right eye - keratoconus
• Left eye - keratoconus frustre
Social history:
• Student
• Active extra-curricular life in theatre
Ocular history:
• RGP corneal lens fits well but gives variable vision
• Due to undergo collagen cross linking
Case study 1 (OP)
Clinical details (OP)
Unaided
Last refraction
Current lens
6/24
Plano / -5.00 x 55 (VA 6/7.5)
Kerakone 7.10 : 8.70 / -2.00 (VA 6/7.5 variable)
Movement
Movement
Movement
Case study 1 (OP)
Fitting sequence with Kerasoft IC (supplied by Ultravision, UK)
Lens Specification Movement
Stability
Other characteristics
Impression / Action
Good
Stable in primary gaze
Slides around laterally
Flat fit or toric bearing
surface - try steeper BOZR
8.20:14.50 STD
Minimal
10o stable nasal
rotation
VA better immediately
post blink
Steep - return to flatter
BOZR and increase
diameter to stabilise
8.40:15.00 STD
Good
Stable vertical laser
mark
Good, stable VA
Good fit
8.40:14.50 STD
Case study 1 (OP)
Clinical details (OP)
Unaided
Last refraction
Current lens
Kerasoft IC ordered
6/24
Plano / -5.00 x 55 (VA 6/7.5)
Kerakone 7.10 : 8.70 / -2.00 (VA 6/7.5 variable)
8.40 : 15.00 : Plano / -1.75 x 60 (VA 6/7.5 stable)
Case study 1 (OP)
• Outcome:
– Stable VA and immediate tolerance.
• Comment:
– Good first choice lens for one eye only
– Suits px social pursuits well
– Appropriate pre / post collagen cross linking
– Stable VA when RGP failed.
Case study 1 (OP)
• Epilogue
– Collagen cross linking right eye
Case study 1 (OP)
• Epilogue
– Collagen cross linking right eye
– After 4 months refitted to:
• Kerasoft IC 8.40 : 15.00 / -0.50
Case study 1 (OP)
• Epilogue
– Collagen cross linking right eye
– After 4 months refitted to:
• Kerasoft IC 8.40:15.00 / -0.50
– Comparison to standard SCL:
• High contrast VA better with Kerasoft IC
• Low contrast VA slightly better with standard design
Case study 1 (OP)
• Epilogue
– Collagen cross linking right eye
– After 4 months refitted to:
• Kerasoft IC 8.40:15.00 / -0.50
– Comparison to standard SCL:
• High contrast VA better with Kerasoft IC
• Low contrast VA slightly better with standard design
– Px continues to wear Kerasoft IC
Case study 2 (MH)
52 year old male
Diagnosis:
• Right eye - keratoconus
• Left eye – keratoconus
Case study 2 (MH)
52 year old male
Diagnosis:
• Right eye - keratoconus
• Left eye – keratoconus
Social history:
• Banker
• Main hobby: long distance running
Case study 2 (MH)
52 year old male
Diagnosis:
• Right eye - keratoconus
• Left eye – keratoconus
Social history:
• Banker
• Main hobby: long distance running
Ocular history:
•
Wearing corneal RGP lenses
– Left eye:
• Increasingly difficult to fit due to advancing distension of inferior cornea
• Always poorer VA compared to right eye
Case study 2 (MH)
52 year old male
Diagnosis:
• Right eye - keratoconus
• Left eye – keratoconus
Social history:
• Banker
• Main hobby: long distance running
Ocular history:
•
Wearing corneal RGP lenses
– Left eye:
•
•
•
•
Increasingly difficult to fit due to advancing distension of inferior cornea
Always poorer VA compared to right eye
Increasingly poor comfort and lens pops out frequently
Unable to tolerate scleral lens
Case study 2 (MH)
Clinical details (MH)
Unaided
3/60
Last refraction
-8.00 / -6.00 x 65 (VA 6/38)
Current lens spec Rose K2 6.40 : 9.80 / -4.25 (VA 6/19 distorted)
Case study 2 (MH)
Fitting sequence with Kerasoft IC (supplied by Ultravision, UK)
Lens Specification Movement
8.40:14.50 STD
8.00:14.50 STD
Excessive
2mm
Stability
Other characteristics
Impression / Action
Unstable
Inferior fluting
Flat fit - try steeper BOZR
Slightly tight on superior
Better but still rotating
edge, slight inferior lift
on blink
on blink
Slightly flat - try steeper
BOZR
7.80:14.50 STD
0.5mm
Unstable, bobbing
Superior edge too tight
Periperhal sector
management control
required
7.80:14.50
FLAT 2 : STD
1.5mm
Stable
Good edge fit 360o
Satisfactory fit
Clinical details (MH)
Unaided
3/60
Last refraction
-8.00 / -6.00 x 65 VA 6/38 (20/125)
Current lens spec
Rose K2 6.40 : 9.80 / -4.25 VA 6/19 (20/63) distorted
Kerasoft IC ordered 7.80 : 14.50 FLT2 : STD / -9.75 / -4.00 x 95 VA 6/15 (20/50) undistorted
Option: fit with flatter BOZR and steepen inferior periphery
Case study 2 (MH)
• Outcome:
–
–
–
–
slightly improvement to VA v’s corneal RGP
reduced distortion
much improved comfort
no popping out
• Comment: soft lenses can equally be applied to
more advanced cases of corneal ectasia including
those which do not improve satisfactorily with
conventional RGP lenses.
Case study 3 (SH)
68 year old female
Diagnosis:
• Right eye – corneal graft (x2) for Fuchs Endothelial
Dystrophy
Case study 3 (SH)
68 year old female
Diagnosis:
• Right eye – corneal graft (x2) for Fuchs Endothelial
Dystrophy
• Right eye – phacoemulsification with toric IOL
Case study 3 (SH)
68 year old female
Diagnosis:
• Right eye – corneal graft (x2) for Fuchs Endothelial
Dystrophy
• Right eye – phacoemulsification with toric IOL
• Left eye – FED (awaiting graft)
Case study 3 (SH)
68 year old female
Diagnosis:
• Right eye – corneal graft (x2) for Fuchs Endothelial
Dystrophy
• Right eye – phacoemulsification with toric IOL
• Left eye – FED (awaiting graft)
Other ocular history:
• Right eye:
– Tilted graft with supero-nasal lift
– Previous non-tolerance to spectacles and RGP corneal lens
Case study 3 (SH)
68 year old female
Diagnosis:
• Right eye – corneal graft (x2) for Fuchs Endothelial
Dystrophy
• Right eye – phacoemulsification with toric IOL
• Left eye – FED (awaiting graft)
Other ocular history:
• Right eye:
– Tilted graft with supero-nasal lift
– Previous non-tolerance to spectacles and RGP corneal lens
Case study 3 (SH)
Clinical details (SH)
Unaided
Last refraction
6/60
+2.50 / -9.00 x 175 VA 6/9 (20/30)
Case study 3 (SH)
Case study 3 (SH)
• Scleral lens fitted:
– 16.5mm good fit
– Spherical over refraction: VA 6/38 (20/125)
– Sph-cyl over refraction: VA 6/24 (20/80)
• Soft Specialty CL fitted:
– Kerasoft IC 8.60:14.50:STP2
– +4.50 / -8.00 x 180 VA 6/9 (20/30)
Case study 4 (CS)
32 year old male
Diagnosis:
• Right eye – corneal graft for keratoconus
• Left eye – mild keratoconus
Case study 4 (CS)
32 year old male
Diagnosis:
• Right eye – corneal graft for keratoconus
• Left eye – mild keratoconus
Social history:
• Electrician
Ocular history:
• Non tolerance to RGP corneal lens due to working environment
Case study 4 (CS)
32 year old male
Diagnosis:
• Right eye – corneal graft for keratoconus
• Left eye – mild keratoconus
Social history:
• Electrician
Ocular history:
• Non tolerance to RGP corneal lens due to working environment
• Right eye: superior neovascularisation into the graft
Case study 4 (CS)
Kerasoft IC 8.60 : 15.00 STEEP 2 +2.00 / -7.50 x 172 in situ
Case study 4 (CS)
Kerasoft IC 8.60 : 15.00 STEEP 2 +2.00 / -7.50 x 172 in situ
Case study 4 (CS)
Kerasoft IC 8.60 : 15.00 STEEP 2 +2.00 / -7.50 x 172 in situ
Case study 4 (CS)
Kerasoft IC 8.60 : 15.00 STEEP 2 +2.00 / -7.50 x 172 in situ
Case study 4 (CS)
Outcome:
• Good, stable visual acuity 6/6 (20/20)
• Excellent tolerance
• Appropriate for working environment
Case study 4 (CS)
Outcome:
• Good, stable visual acuity 6/6 (20/20)
• Excellent tolerance
• Appropriate for working environment
Clinical:
• current wearing time 12/24 + 5/7
• neovascularisation stable
Case Study 5 (AG)
15 year old male
Diagnosis:
• Right eye – keratoconus
• Both eyes – allergic eye disease
Case Study 5 (AG)
15 year old male
Diagnosis:
• Right eye – keratoconus
• Both eyes – allergic eye disease
Social history:
• Student
• Rugby player
Case Study 5 (AG)
15 year old male
Diagnosis:
• Right eye – keratoconus
• Both eyes – allergic eye disease
Social history:
• Student
• Rugby player
Ocular history:
•
Right eye:
– Struggling to tolerate rapidly changing astigmatic spectacle correction
– Fitted with RGP corneal – mobile and tearing
Case Study 5 (AG)
Clinical details (AG)
Refraction
-0.25 / -9.50 x 30 VA 6/12 (20/40)
Case Study 5 (AG)
Clinical details (AG)
Refraction
-0.25 / -9.50 x 30 VA 6/12 (20/40)
Fitting sequence with Reflex Kera (supplied by No7, UK)
Lens Specification Movement
Stability
Other characteristics
Impression / Action
7.60 : 14.20
0.5mm
Stable temporal
rotation 10 degrees
VA better immediately
post blink
Steep fit - flatten BOZR
7.90 : 14.20
1mm
Stable
Stable VA
Good fit
Case Study 5 (AG)
Case Study 5 (AG)
Clinical details (AG)
Refraction
-0.25 / -9.50 x 30 VA 6/12 (20/40)
Fitting sequence with Reflex Kera (supplied by No7, UK)
Lens Specification Movement
Stability
Other characteristics
Impression / Action
7.60 : 14.20
0.5mm
Stable temporal
rotation 10 degrees
VA better immediately
post blink
Steep fit - flatten BOZR
7.90 : 14.20
1mm
Stable
Stable VA
Good fit
Final lens ordered: 7.90 : 14.20 : -1.00 / -6.00 x 35
VA 6/6 (20/20)
Summary
• Soft lenses:
– can be successfully applied in fitting mild, moderate
and advanced irregular corneas
• Indications:
•
•
•
•
•
•
new fits
uniocular fits
dusty /challenging environmental / occupational conditions
poor tolerance of corneal lenses
other lens types are unsatisfactory
collagen cross linking
Summary
• Clinical pearls:
– Movement
– Rotation
– Visual acuity
– Comfort
Thank you
[email protected]