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Home , Conjunctivochalasis

6/23/16

Timothy B. Cavanaugh, MD Cavanaugh Eye Center Overland Park, KS

UMKC Annual Update in 2016

• No financial conflicts or disclosures

• Definition: Corneal disorder marked by 15-20 year progression of ectasia, corneal thinning, weakening, distortion, and corneal scarring

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• Stages of Development ─ FLC on topography ─ Form fruste disease & trait: • Stable non-progressive ectatic disease ─ Early Stage (spectacle phase) • Increasing and • Glasses still effective ─ Mid-Stage (contact ) • Increasing myopia and irregular astigmatism • Not correctable in glasses • Requires GPCLs or other MNCLs

• Stages of Development (cont) ─ Advanced Stage (surgery phase) • Severe irregular astigmatism • Inability to wear CLs to obtain adequate vision • Requires surgery ─ Burnout Stage • Disease becomes slowly or non- progressive over age 60

• Disease Diagnosis ─ Clinical findings • changes • Slit lamp findings ─ Topog r a phy • Standard topography ─ Measures anterior curve only ─ Can miss early disease • Orbscan or Pentacam are better ─ Ant and post curvature data ─ Decentered apex – front and back ─ Corresponding thin spot ─ Elevated ratio

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“Normal” Eye

Anterior & Posterior Float

Decentered Apex + Thin Spot

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Elevated Ratio 0.056mm

• Treatment Options ─ Depend on disease severity ─ Move down list as disease progresses 1. Observation 2. Glasses or soft CLs 3. GPCLs or other MNCLs 4. Collagen Crosslinking 5. INTACS 6. CK for keratoconus 7. PRK / PTK 8. Corneal transplantation

• To r i c soft lenses: ─ Mild ectasia ─ Best success with pellucid-type ectasia ─ Rotational stability is key ─ If stability cannot be achieved, move on • Corneal GP lenses: ─ Mild to severe ectasia ─ Central ectasia is best ─ Relative low cost ─ Lens ejection & comfort are biggest issues ─ Front and back surface torics are not stable • Cannot “lock-in” to irregular astigmatism

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• Hybrid lenses: ─ Mild to moderate ectasia ─ Central ectasia is best ─ Newest generation is Synergeyes UltraHealth • SiHy skirt, better corneal touch distribution, better tear exchange ─ If fit correctly, good comfort & stable vision ─ High cost / 6 mo replacement ─ Watch lens binding / graft-host interface touch in post-PK

• Specialty Soft ─ Mild to moderate ectasia ─ High modulus ─ Lens does not drape irregularity like standard SCL ─ Lens manufactures tout comfort – variable • Thick lens profile ─ Newer modality, not yet a “go-to” lens

• Scleral GP lenses ─ All types & locations of ectasia ─ Most customizable ─ Becoming mainstream ─ Technology advancements in materials • High Dk

• Astigmatism ─ MNCLs correct irregular / corneal astigmatism ─ Internal astigmatism is not corrected ─ Watch for high lenticular astigmatism • Crystalline lens • To r ic IOLs ─ Best technology for toric MNCLs exists with sc lerals, howev er still sub-optimal • 50% success rate

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• Irregular ─ Diseases, dystrophies, post-surgic al

• Ocular surface disorders ─ ─ LSCD, SJS, exposure

• High ametropia • Active lifestyles • Unsuccessful fit in another modality

• PROS ─ Vision: similar or enhanced vs. corneal GP lenses ─ Improvement in dry eye signs/symptoms ─ Lens stability ─ No lens ejection ─ Comfortable ─ Protection

• CONS ─ Cost ─ Handling difficulty ─ Extra solutions ─ Longer chair time?? (not really)

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• Pingueculae • Conjunctivochalasis • Excessive Ocular Reflex • Higher Order Aberrations

It’s important to set realistic expectations!

• Vault the entire + limbus ─ Literature: • Low = 50-100 microns (mc) • Moderate = 100-250 mc • High = 250-400 mc • Oxygen transmissibility! ─ 40mc tear lens visible with NaFl ─ Manufacturers: • Design dependent

• Solutions to Clean Lenses ─ Need for less abrasive cleaners • Clear Care • Boston Simplus • Optimum by Lobob • Clear Care • Solutions to FillLenses ─ Purilens Plus • PF, buffered ─ Sodium Chloride Inhalation Solution 0.9% 5mL (100 dose pack vials) • PF, not buffered ─ PF ATs (not cost effective)

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• Preservative-free artificial ─ For use inside or outside of lenses • Remove lenses prior to instillation of medicinal drops • No sleeping in lenses unless indicated ─ Minimal research to date

Keratoconus

• Definition: minimally invasive procedure that strengthens the cornea to halt keratoconus progression to preserve vision and potentially eliminate the need for corneal transplantation.

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• Mechanism of Action: ─ Riboflavin (vitamin B-12) drops + UV light ─ UV light shifts riboflavin, releases free radicals ─ Radicals cause collagen lamellae to bond to one another

• Patient selection and indications: ─ Keratoconus & post-LASIK ectasia patients ─ Anyone showing progression of ectatic disease • Minimum corneal thickness of 400 microns ─ Young and old are both candidates ─ No HSV or corneal scarring ─ Combination procedures • INTACS, CK, and/or PRK

• Background & current status ─ Developed in Switzerland decades ago ─ Landmark study: “Induction of Cross-links in Corneal Tissue”; Spoerl, Huhle, Seiler. Exp Eye Res. 1998 ─ Faster treatment times approved in most countries except USA (14 minutes or less) ─ USA approved utilizing Dresden protocol (60 minutes)

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• Product update: ─ Avedro: FDA approval announced 04/2016 ─ CXLusa: ongoing clinical trials, future approval?? ─ Peschke: • Previous US study rejected by FDA • Riboflavin not meeting FDA standards ─ 62 current CXL studies registered with the FDA ─ Insurance coverage?

• Avedro:

─ KXL System w/ PHOTREXAâ ─ Indication: progressive keratoconus ─ Contraindications: few ─ Warnings / Precautions: ulcerative keratitis (epi defect)

Avedro (cont) • Adverse Reactions (most common): ─ (haze) ─ Punctate keratitis ─ Corneal striae ─ Corneal epithelium defect ─ Eye pain ─ Reduced visual acuity ─ Blurred vision

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Avedro (cont) • Dosage & Administration ─ PHOTREXA VISCOUS: yellow, sterile, buffered viscous riboflavin solution, 301-339 mOsm/kg ─ PHOTREXA: yellow, sterile, buffered riboflavin solution, 157-177 mOsm/kg ─ PHOTREXA VISCOUS is used initially ─ PHOTREXA is used if adequate corneal thickness is not obtained

Avedro (cont) • Results: ─ Three studies used for approval ─ All studies:

• Increasing improvement in Kmax throughout the year of follow-up • Avedro offering • Average Kmax @ 12 mohad been reduced by 1.4-1.7D accelerated forms of CXL outside of the US • Non treated eyes Kmax had progressed 0.5-0.6D

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• CXL USA ─ Group of surgeons formed CXL USA to assist patients with access to CXL treatments and studies ─ 6 total FDA studies collaborated by CXL USA • Are they seeking approval? ─ Keratoconus, Ectasia, Degeneration, Form Fruste Keratoconus, Infectious Keratitis ─ Outcomes: biomechanical stability of cornea, change in BCSVA / manifest refraction / wavefront refraction and abberrations

• Peschke ─ CCL-Vario ─ Appears not be a player in the US ─ 3 total FDA studies collaborated by Peschke • All 3 studies – no recent activity ─ Keratoconus, progressive kerato co nu s ─ Outcomes: change in keratometry, topography, endothelial cell count, visual acuity, manifest refraction

• Postoperative care ─ Post-op medications: • To p i c a l s t e r o i d 4-3-2-1 (weekly) taper • Fluoroquinolone antibiotic + bro mfen ac X 1 week ─ Leave BCL 3-5 days or until re-epithelialization ─ Early effect seen in 1 week ─ Full effect may take months to years ─ Expect: • Reduction/halting of ectasia progression • Flattening of cornea with reduction of cylinder • Improvement in best corrected vision ─ Potential complications: sterile or infectious corneal infiltrates, poor healing epithelium, corneal haze

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• Stabilize corneal fluctuations in post-RK patients • Sterilize / treat corneal infectious ulcers • Treat autoimmune corneal melts • Secure possible instability of vision after LASIK • Halt progression of post-LASIK ectasia • Prevent post-LASIK ectasia proactively? • “Lock-in” corneal stability in non-complicated LASIK (ex: LASIK Xtra – Avedro)

Keratoconus

• Definition: minimally invasive procedure that flattens the cornea to improve the corneal profile and re-establish success in contact lens wear. Can improve vision, stabilize the cornea to slow progression of ectasia, and delay the need for corneal transplantation

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• Mechanism of Action: ─ Implantation of various thickness plastic half circle segments into intra-stromal channels ─ Elevates mid-peripheral cornea ─ Flattens center

• Background and current status ─ Developed in 1980s for treatment of low levels of myopia – Keravision, Inc ─ Myopic indication fell off once LASIK approved and became more successful ─ Company sold to Addition Technology and indic ation c hanged to treatment of keratoconus ─ IRB involvement needed for FDA approval for use in keratoconus ─ Channels can be created manually with stromal dissec tor or with Femtosec ond laser ─ Recently asymmetric segment packaging available • Often use 2 different thickness segments depending on topography

• Patient selection ─ Keratoconus & post-LASIK ectasia patients ─ Anyone showing progression of ectatic disease whose corneal thickness is at least 400 microns over incision site ─ Primarily for patients who are failing CLs and are heading towards corneal transplantation ─ Can be combined with CXL, CK, PRK

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• Patient selection (cont) ─ Patient expectations are key • Return patient to CL success • Delay PK • Not to eliminate CLs and return good vision in glasses ─ Young and old are both candidates ─ No HSV or corneal scarring

• Procedure specifics ─ Topical or PBB anesthesia ─ Mark corneal center and location of channel incisions with inked template marker ─ Pachymetry measure thickness over intended incision site as determined by steep axis on Orbscan ─ Make incision @ 70% of measured corneal depth with diamond blade

• Procedure specifics (cont) ─ Start channel dissection with manual dissectors ─ Apply suction to firm eye similar to making LASIK flap ─ Thread semi-circular channel dissectors in each direction in deep stroma ─ Insert INTACS ring segments ─ Close incision with single 10-0 nylon suture

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• Postoperative care ─ Post-op meds • Topic a l st e r oid + fluoroquinolone antibiotic X 1 week ─ Early effect seen in one week but full improvements in corneal topography take months ─ Expect flattening of cornea with reduction of myopia and astigmatism, improvement in CL fit / comfort and improvement in best corrected vision ─ Potential complications: channel deposits, sterile or infectious corneal infiltrates, corneal perforation, erosion of segments, worsening of irregular astigmatism

Keratoconus

• Definition: minimally invasive procedure that uses radio frequency energy to steepen the corneal curvature

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• Mechanism of Action: application of intra stromal radio frequency energy with a probe to tighten the helix and shrink corneal collagen thus steepening the corneal curvature.

• Background ─ Outgrowth of older procedures • Thermal keratoplasty • Holmium laser thermokeratoplasty ─ Developed in 1990s for treatment of low levels of hyperopia and ─ Initially owned by Refractec, bought by Precision Lens ─ Still used for treatment of presbyopia and hyperopia in some cases. 8-16 circular spots applied symmetrically to steepen central cornea uniformly. These indications fell off once LASIK approved and become more successful

• Use in Keratoconus treatment ─ Apply 2-3 spots in flat axis of astigmatism to improve the corneal profile and re-establish success in contact lens wear. ─ Use with intraoperative keratometry ─ Combine with CXL, INTACS, PRK ─ Ten d s t o r egr es s – less so after CXL ─ Can improve best corrected vision.

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• Patient selection ─ For both keratoconus and post-LASIK ectasia patients ─ Recommended for keratoconus patients with severe asymmetric irregular astigmatism that is affecting best corrected vision and contact lens success ─ Primarily for patients who are failing CLs ─ Patient expectations realistic ie to return patient to CL success and delay PK. Not to eliminate CLs and return good vision in glasses ─ Young and old are both candidates ─ No HSV or corneal scarring

• CK procedure specifics ─ To p i c a l a n e s t h e s i a ─ Mark corneal center and location of topographical corneal flattening with inked template marker ─ Use intra operative keratometer to assess corneal shape in real time ─ Apply 1-2 CK spots by inserting wire probe into corneal stroma at optical zone of 6- 8mm ─ Apply CK spots until keratometer profile improves and slightly over corrects to allow for expected regression

• Postoperative care ─ Postop meds • To p i c a l s t e r o i d a n d fluoroquinolone antibiotic for one week ─ Early effect seen in one week but full improvements in corneal topography take months ─ Expect segmental steepening of the cornea with improvement in symmetry of astigmatism, improvement in CL fit / comfort and improvement in best corrected vision ─ Potential complications: regression of effect, sterile or infectious corneal infiltrates, poor epithelial healing over spots, worsening of irregular astigmatism

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• Current role ─ Thinning of cornea with laser can lead to accelerated progression of ectasia ─ Limited use for patients who have not been crosslinked • Use only in patients who are close to needing PK • Patients with elevated “nipple” apical scars preventing successful CL wear and decent vision • Flatten and lighten scar to re-establish success in CL wear • Inform patient about potential for progression of disease

• Future role ─ more viable treatment option after cornea has been stabilized by crosslinking ─ Less risk of causing acceleration of ectasia ─ Use in combination with CXL, INTACS, CK to reshape cornea and reduce high myopia and astigmatism ─ Use MitomycinC to prevent scarring

• Use to reduce high myopia in keratoconus patient • Does not weaken the cornea • Very accurate – IOL power based on refraction • Best after cornea stabilized with crosslinking • Optimize corneal profile / keratometry first with INTACS, CK etc first

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Keratoconus

• Definition: full or partial thickness transplantation of the central cornea to remove ectasia and scarring in order to improve corneal shape and clarity and allow for vision improvement

• Mechanism of Action: ─ Full thickness (penetrating keratoplasty): surgical replacement of full thickness cornea in central 8-9mm with donor tissue ─ Partial thickness (deep anterior lamellar keratoplasty LK): surgical replacement of 90% of anterior stroma with preservation of descemets membrane and endothelium

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• Background and current status: ─ Longstanding end stage treatment for advanced keratoconus ─ Proven success with reasonably low complication rates ─ Results greatly improved with newer technology instrumentation and surgical techniques ─ Most surgeons do PK for kerato co nu s

• DALK: ─ LK “big bubble” technique uses air injected deep in corneal layers ─ Separates deep lamellae from Descemets membrane ─ Can replace entire cornea except DM and endothelium ─ This reduces risk and eliminates endo rejection ─ Technique is very difficult –higher complication rates at this time

• Patient selection ─ For both keratoconus and post-LASIK ectasia patients ─ Recommend for anyone showing progression of ectatic disease who are failing CLs and other aforementioned surgical techniques ─ Apical scar and post-hydrops patients ─ Patient expectations realistic ie slow recovery best of vision. Will not necessarily eliminate CLs and return good vision in glasses ─ Young and old are both candidates

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• PK procedure specifics ─ PBB anesthesia ─ Obtain donor tissue via eyebank ─ Cut donor with trephine blade to desired diameter ─ Mark patients corneal center and location sutures with inked template marker ─ Remove patients central cornea with same size trephine blade ─ Suture donor in place with 10-0 nylon suture – usually combination of 12 interrupted sutures and a 12 bite running suture ─ Use intra operative keratometry to adjust suture tension and minimize astigmatism on the table ─ Re-inflate eye and ensure it is water tight

• Postop meds ─ Durezol on a tapering dose until gone then switch Lotemax. Will use Lotemax forever once a day for rejection prevention ─ Fluoroquinolone antibiotic for one week or until epith healed ─ Neopolydex ointment at bedtime until tube gone

• 3 healing phases: ─ Epithelial healing ─ Clearing of donor stroma ─ Reduction of post PK astigmatism • Potential complications: primary graft failure, graft rejection, poor epith healing, sterile or infectious corneal infiltrates, suture abscesses, broken sutures, irregular astigmatism, graft rupture

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• Strengthen ─ Collagen crosslinking to stabilize • Smooth and Round ─ CK to steepen local area of topographical flattening ─ INTACS to flatten ectatic area • Focus ─ PRK for mild residual myopia and/or astigmatism ─ Staar Visian ICL for high residual myopia • Delay / prevent PK ─ Happier patient!!

• Keratoconus treatment options are advancing and evolving • Combining techniques can be synergistic • Team work for best visual outcomes • Work with a comprehensive anterior segment surgeon so that your patient has all the options

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