Post on 12-Apr-2017
A Option for KeratoconusKeratoconus Intacs -1 Day PKP -1 Week
Contact Lens Intolerant Keratoconus Steep K ‘s, 45 to 60 Changing refractions, eyes irritated, frequent
visits/re-fits Lenses not providing functional vision
Outright failure Shortened wearing time Inability to achieve 20/40
“keratoconus personality” exacerbated Apprehensive about transplant
Active, younger or risk averse
Objective - Bridge the gap between frustration and (PKP) “the point of no
return”
Reshape the Cornea for CL Success
Oklahoma optometrist first conceptualized the idea in 1978
One of the early medical champions of contact lenses in the U.S.
Developed CorneaScope in late 1960s - led to today’s topography
Gene Reynolds, O.D.1921 - 1994
INTACS HistoryConcept for Corneal Reshaping
Arc-Shortening Model for Treating Myopia: Preoperative Representation of
the Cornea
How does it work?
Arc-Shortening Model for Treating Myopia: Representation of the Cornea
After Placement of INTACS Inserts
How does it work?
History
Adjustable Ring1984
As conceived by Dr. Reynolds
19781978 – A.E. Reynolds, O.D. conceives of – A.E. Reynolds, O.D. conceives of Intrastromal Corneal Ring (ICR)Intrastromal Corneal Ring (ICR)
19851985 - First pre-clinical studies on Dr. Reynolds' product - First pre-clinical studies on Dr. Reynolds' product
19911991 - First human clinical trials begun - Brazil - First human clinical trials begun - Brazil
1996 1996 -- U.S. myopia clinical trial begun, 150º ICRU.S. myopia clinical trial begun, 150º ICR- CE Mark approval of ICR in Europe,- CE Mark approval of ICR in Europe, -1.00 to -4.50 -1.00 to -4.50
DD
19971997 - Joseph Colin, MD inserts first ICR for Keratoconus - Joseph Colin, MD inserts first ICR for Keratoconus
Milestones
INTACS Design Features Precision manufactured
to ± 0.01mm: •150° arcs PMMA•Unique hexagonal cross-
section design with 7mm wide optical zone
•Positioning holes for manipulation
Inserts placement:•In peripheral cornea•Between stromal layers
Stromal Lamellae
6.9 mm
8.1 mm
Stromal Lamellae
How INTACS Work…
Inserts placed at 75% corneal depth
Inserts separate corneal lamellae
Separation shortens corneal arc length
Central cornea flattens Increased flattening
achieved with thicker segments
1999 - FDA approval for myopia, -1.00 to -3.00 D
2001 - Addition Technology purchased INTACS technology to pursue keratoconus indication
2003 - CE approval granted for keratoconus in Europe
2004 - FDA approval for keratoconus under Humanitarian Device Exemption (HDE)
2005 – Over 5000 INTACS corneal implants procedures for keratoconus performed worldwide
Milestones cont’d
Keratoconus
Non-Inflammatory Ectasia• Stromal Thinning• Disruption of Bowman’s
Membrane
Corneal Ectasia• Myopia• Irregular Astigmatism
Optical Correction• Spectacles– early• Contact Lenses– later
Keratoconus
Demographics•Estimates vary from 50
to 170 per 100,000
Obscure Etiology•Heredity•Allergies, Eye Rubbing
Why Does the Cornea Bulge in Keratoconus?
Corneal tissue is abnormal• Too elastic?• Abnormal cross-linking of
collagen?
Loss of structural integrity of Bowman’s Layer?
Keratocyte apoptosis• Trauma (eye rubbing)
Corneal tissue bulges because it is too thin?
Current Surgical Options - Keratoconus
10% to 20% of Keratoconus Patients Ultimately Require Surgery
Lamellar Keratoplasty• Interface haze limits visual result
Penetrating Keratoplasty• Most frequent procedure – 4,771 cases in 2004 (US)• 80-90% successful• Issues
Graft rejection rate 17.9% Continued astigmatism Endothelial cell loss (limited longevity of graft) Recurrence of Keratoconus
INTACS… a New Surgical Option
Goal is to restore functional vision
•Effective functional refraction with soft, soft-toric, or rigid contact lenses
•Create cornea more receptive to contact lenses
INTACS Normalize Corneal Shape
The INTACS Procedure
Courtesy David Schanzlin, MD Shiley Eye Inst. UCSD
Pre-Op UCVA 20/200 MR: -4.75 + 5.25 X 005 = 20/40 RGP intolerant
Post-Op (Day 1)
UCVA 20/50++ MR: -1.00 + 2.75 X 150 = 20/20 Soft Toric
Courtesy David Schanzlin, MD Shiley Eye Inst. UCSD
Procedure Outcome
“ Fitting CL’s on keratoconus patients who have INTACS is feasible and has a role in augmenting
their vision” Nepomuceno, Boxer Wachler, Weissman, CLAE 2003 175-180
pre-op BCVA post-op BCVA post-op BCLVA Lens
31 F 20/32 20/25 20/16 soft toric
44 M 20/125 20/50 20/25 cust. RGP
34 M 20/63 20/40 20/20 cust. RGP
All were CF UCVA pre-op and 20/200 or better post-op
INTACS Case FilesPre-Op
UCVA CF BCVA: 20/50 MR: -7.00 -6.00 @ 60 Max K: 46.60 @ 175 Custom RGP Intolerant
Case 1
Anterior Posterior
INTACS Case Files
UCVA 20/80 BCVA: 20/30 MR: -2.00 -2.75 @ 60 Max K: 43.40 @ 14 Soft Toric
Case 1Post-Op Anterior Posterior
Architecture Modification
Architecture Modification
Pentacam Images
INTACS Case Files
UCVA CF BCVA: 20/50 MR: -4.75 + 5.00 @ 20 Max K: 55.78 @ 90 Custom RGP Intolerant
Case 2OD Pre-OP
INTACS Case Files
UCVA 20/40 BCVA: 20/25 MR: -2.00 Max K: 51.69 @ 89 RGP Tolerant
Case 2OD Post-OP
INTACS Optics
Maintains prolate cornea
Enhances structural integrity (second limbus)
Additive – Removable - Replaceable
Large, clear central optical zone
INTACS & The Prolate CorneaINTACS LASIKNormal
Cornea
In vivo Hartman-Shack analysis
Peer Reviewed Literature INTACS for Keratoconus
Primary Auth. Title Eyes
Levinger Keratoconus Managed with Intacs, Arch Ophthal, Oct 05 53
Uusitalo Treating Keratoconus with Intacs, JRS May 05 50
Alio One or Two Intacs for correction of Keratoconus, JCRS May 05 26
Colin Current Surgical Options for Keratoconus, JCRS Feb 03 0
Tunc Intacs for Asymetrical Astigmatism of Keratoconus, Journal of French Ophthal. Oct 03 9
Boxer Wachler Intacs for Keratoconus, Ophthalmology May 03 74
Colin Intacs and Refractive IOL to Correct Keratoconus, JCRS Apr 03 1
Siganos Management of Keratoconus With Intacs, AJO Jan 03 33
Colin Intacs for Treating Keratoconus, Ophthalmology Aug 01 10
Colin Utilization of Refractive Technology in Keratoconus and Transplants, Cur Opin Ophthal 2002 0
AlioChanges in Keratoconic Corneas after Intacs Expantation and Reimplantation, Opthalmology Apr
04 5
Lemp Intacs Safety in Keratoconic Eyes, Invest Ophthalmol Vis Sci ARVO 04 164
Colin Correcting Keratoconus with Intracorneal Rings, JCRS Aug 00 10
Guell Are Intacs Usefull in Refractive Surgery, Curr Opinion Ophthal. 2005 222
Weissman Feasibility of Contact Lens Fitting on Keratoconus Patients with Intacs, CLAE 2003 3
Total Eyes Summarized 660
Unique Eyes Summarized 338
INTACS Clinical Overview First case 1997: Joseph Colin, MD
•Decentered Cone
•Segment Placement Superior thin segment : 0.25 mm Inferior thick segment : 0.45 mm
•Very encouraging results Patient scheduled for immediate PKP, Transplant has been deferred 7+ years with acceptable
BSCVA Reduction in myopia and astigmatism Results stable over time
Combined Studies 1997- 2003
Colin (2001) – 10 eyes • Ophthalmology 2001; 108:1409-1414.
Siganos (2003) – 33 eyes • American Journal of Ophthalmology 2003; 135:1:64-70.
Boxer-Wachler (2003) – 74 Eyes• Ophthalmology. 2003; 110:1031-1040.
European Clinical (2003) – 34 eyes • Accepted for Publication Ophthalmology
Combined Studies 1997- 2003
Change UCVA
0%
20%
40%
60%
80%
100%
Gain 2 or More Lines
No Change +/- 1 Line
Loss 2 orMore Lines
European Study Siganos Boxer Wachler
78%
22%
0%
67% 72%
33%
19%
9%0%
Combined Studies 1997 - 2003 Change BSCVA
0%
20%
40%
60%
80%
100%
Gain 2 or More Lines
No Change +/- 1 Line
Loss 2 orMore Lines
European Study Siganos Boxer Wachler
62%
32%
6%
45%45%52%
51%
4%3%
CL Intolerant - Pre-Op BCVA Achieved to Complete Exam
Combined Studies 1997 - 2003 Follow-up shows stable and lasting effect
Very Few Surgical Complications Observed
Postoperative Complications• Superficial placement • Segment migration• Visual symptoms• Lack of effect
Manageable with INTACS Removal• 14/174 eyes (8%)• Majority of patients returned to preoperative refraction upon
removal• Several have gone on to have successful corneal transplantation
European Keratoconus Study Results Summary
Dr. Joseph Colin (France) pioneered the use of INTACS in Keratoconus
First case in 1997
7 years follow up with stable results
Very few INTACS patients have required corneal transplants in 7 years
In the few cases where PKP was performed, no problems were reported
European Keratoconus Study
Change in MRSE• Mean - 3.1 Diopters Corrected• Range -1.6 to 8.7 Diopters
Change in Cylinder• Mean - 2.9 Diopters Corrected• Range - 0 to 7.5 Diopters
Stability of refraction achieved at 3 to 6 months
• 75% within ± 1 Diopter• 50% within ± 0.5 Diopter
European Keratoconus Study2 year data - Joseph Colin, MD*
96 of 100 eyes, initially referred for PKP, successfully implanted with INTACS and remain stable after 24 months
100% became contact lens tolerant, some patients became correctable with spectacles and a subset required no correction
80% have improved UCVA and 68% improved BCVA at year 2
Manifest refraction, cylinder, MRSE and pachymetry continued to improve at year 2 over year 1 and preoperative exams
* Accepted for Publication JCRS
INTACS – PKP Comparison
+8.00 (.)-2.00 X 180°-0.75TransplantIntacs
INTACS - PKP ComparisonPKP
Irreversible Procedure Time: 1 Hour Rehab Time: Immed-
18 MonthsIntraocular Procedure Complications
• Cataract• Glaucoma• Endophthalmitis• Rejection• Expulsive hemorrhage• Neovascularization• Induced astigmatism• Disease recurrence• Risk of viral transference
INTACS Reversible Out-Patient
Procedure Time: 20-30 Minutes Rehab Time: 1-2 Weeks
(Visual Function Immediate) Corneal Lamellar Procedure Periodic Follow-up Complications
• Unsatisfactory ring placement• Segment extrusion(All easily managed with segment removal))
INTACS - PKP ComparisonPKP
Significant loss of endothelial cells
Permanently weakened cornea with risk of additional trauma
Outcomes: unpredictable, often unstable
INTACS
Endothelial cell loss, not clinically significant1
Provides structural integrity, PKP still an option without complication
Outcomes: predictable, case dependent
1Two-Year Endothelial Cell Assessment following INTACS implantation, Azar et al, J Refract Surg. 2001 Sept-Oct
Conclusions: INTACS Intervention is a good
alternative to Transplant Goal of INTACS is to restore functional vision
• Effective functional refraction with soft, soft-toric, or rigid contact lenses is likely
• Creates cornea more receptive to contact lenses
INTACS implantation reduces corneal coning• Central cone is flattened• Asymmetrical cones are repositioned centrally
Post-surgical recovery• Visual improvement can be immediate • Vision stabilizes in months rather than a year or longer
High potential to defer transplant
INTACS Case Files
UCVA CF BCVA: 20/45 MR: -6.25 -4.75 @ 175 Max K: 54.43 @ 79 Custom RGP Intolerant
Case 3OS Pre-Op
INTACS Case Files
UCVA 20/80 BCVA: 20/30 MR: -.50 -3.00 @ 135 Max K: 51.69 @ 89 RGP Tolerant
Case 3OS Post-Op
INTACS Removal & Replacement Summary
Easy to remove
In FDA study, no complications post-removal
Preliminary data indicates that the patients return to their preoperative refractive error in most cases
Patients are able to return to their original mode of correction or to pursue an alternative refractive procedure
Keratoconus Treatment Flow The Old Paradigm
Disease Identification &
ManagementSpectacles, Contacts,
Custom Lenses
Optometric Physician
Identification of Surgical Need
Contact Lens Intolerance or
Central Scarring
Optometric Physician
Work-Up, PKP Surgery, Post-Op1 to 3 Months Patient
Recovery
Surgeon
PKP Post-OpCare
12 to 24 Months
Optometric Physician
Post PKP Fitting Specialty Custom Lenses
Optometric Physician
Long-Term Follow-Up
Specialty CL Fitting, Regular Monitoring (Re-Graft 17.9%)
Optometric Physician
Keratoconus Treatment Flow The New Paradigm
Disease Identification &
ManagementSpectacles, Contacts,
Custom Lenses
Optometric Physician
Identification of Surgical Need
Contact Lens Intolerance or Risk
of Scarring
Optometric Physician
Work-Up, INTACS Surgery, 1-Day & 3-Month Post-Op
1-2 Days Patient Recovery
Surgeon
Ongoing Follow-Up
Include Initial CL Fit
Optometric Physician
Post-Op Management &
Outcome AnalysisRe-Referral if
Complications or Atypical Outcomes
Optometric Physician
Long-Term Follow-Up
Include CL Fitting, Periodic Monitoring
(Defer PKP)
Optometric Physician
Contact lens intolerant keratoconus
Improve contact lens success, UCVA, BCVA
Defer PKP and associated risks
Keep on the conservative side of leading edge patient care technology
Retain patient loyalty and follow-up care
Why recommend INTACS ?
Contact Lens Intolerant Keratoconus
K readings 45 to 60
Contact lenses not providing functional vision Outright failure Shortened wearing time Inability to achieve 20/40 Desire to forestall central scarring
Apprehensive about transplant
Or, if Surgical Intervention is Medically Necessary
Ideal INTACS Patients
Those who strongly desire refractive surgery, but work-up exhibits concerning signs
Posterior anomaly Forme fruste keratoconus or pellucid-like
topography
Those who desire refractive surgery, but fear “no-return” of laser ablation
Wish to retain options for future conditions or technologies
Advanced, Additive, Removable Up to -3.00D sphere and 1.00D astigmatism
INTACS a refractive option for …