S.I.TRA.C. Meeting 21-23 February 2013
PERCORSO FORMATIVO 1 ADVANCED INTERNATIONAL CXL COURSE
ICRS combined with Accelerated CXL
Dr. Lovisolo has no proprietary or financial interest in any device or product mentioned in this presentation
Carlo F. Lovisolo, MD Quattroelle Custom Eye Centers Milan Italy
Since 2006: Topo-guided Ablation (CIPTA) combined with CXL to improve coma & irregular astigmatism
The Athen’s Protocol: Excimer laser (Allegretto) topo-linked ablation Kanellopoulos AJ Clin Ophthalmol 2012;6:87-90
LIGI CIPTA topo-guided transepithelial ablation Stojanovic J Refract Surg 2010;26:145-52
Simultaneous topo-guided PRK + CXL for KC Kymionis GD et al: Am J Ophthalmol 2011;152:748-55
Issues • Hyperopic shift (Dresden protocol) → Gaussian shape: “hot center & cool edges • Overall lack of predictability → Epithelium compensation → Cut rate of KC tissue (achieved vs. expected ablations) • Lack of information on posterior corneal surface → Inaccurate astigmatism correction → Overoblate asphericity • Aberropia (diplopia) from tilt compensation • Safety Limit of 400 µm? • Soaking time after Bowmann removal?
Epithelium compensation revealed with VHF Echography (Artemis 2)
• • • •
Thins over cone apex Thickens at cone base Thins on segments’ top Thickens at segments’ edge
Cornea with ring segments Normal cornea
Keratoconus
OCT Corneal Epithelial Thickness Map First impression Less accurate than Artemis (pixel size around 3 microns) Useful for looking at gross changes
Posterior Corneal Astigmatism & Asphericity
e t a l o Pr
44D
e t a l Ob
42D
43.5 43D
42.5
43D
The new PRECISIO software release includes a “total surface analysis” about astigmatism & asphericity
It shows why when we correct the anterior Q value we achieve an overall postop overoblate shape
Now we can plan adequate astigmatism and asphericity corrections
Tissue sacrifice: Moderate ectasia, nipple cones excellent indications Minimised Ablation (Max depth <50 Îźm, volume 0.5 mm3)
Safety limits: topo-guided ablations not feasible in the vast majority of cases Downward displacement of corneal apex To correct tilt: Max Ablation Depth: 274 Îźm Minimal residual pachymetry: 179 Îźm
Since 1999: ICRSâ&#x20AC;&#x2122;s reproducible flattening & recentering effect The thickest the segment, the largest the flattening effect
,
SI6 mm
The shorter the segment, the bigger the astigmatic correction
SI5 mm
Significant reduction of Coma after ICRS Corneal apex recentered PreOp
Coma: 1.97
PostOp
Coma: 0.52
Triple procedure: 1) ICR 2) after 3-6 months CXL + topoguided ablation
PreOp Required max ablation:118 ablation:11 μm
Post-Ferrara Ring
Post-CXL + Topo-link Max ablation: 39 μm
PreOp
Max depth for simulated topo-link: 97 μm Residual min pachymetry: 366 μm
Post-CXL + Topo-link
Post-ICR
Max depth for simulated topo-link: 31 μm Residual min pachymetry: 432 μm
PreOp
Post-ICR
Post-CXL + Topo-Link Max ablation: 36 Îźm
Best case must become average outcome!
PostOp UCVA 20/25++; BSCVA: 20/20 with -0.50 cyl
24 yo PreOp UCVA 20/200 BSCVA: 20/30 with -5.0 sph -3.0 cyl
Custom Phakic IOL’s Preop BSCVA 20/80 -13.0 -12.0 x 115° Kera Ring + CXL + Topo-link + T-ICL. Postop UCVA: 20/20
Drawbacks of Dresden Protocol • Pain • Long, tedious downtime • Transient (?) loss of BCVA • Unpredictable hyperopic shift (centre vs. periphery effect) • Healing changes of stroma – – – –
Sterile infiltrates Long lasting Haze Scar (Burn?) Keratocyte apoptosis
• Risk of endothelial cell damage (safety pachymetry of 400 µm established) • Some failure to stop progression • Time-consuming, boring procedure → complications • New data available → controversial basic science
Preliminary results after a 15-month experience with Accelerated CXL 3 mW/cm2 typical UVA light in current use
30 mW/cm2 KXL System
9 mm Aperture
Bowmanâ&#x20AC;&#x2122;s
Center to edge beam uniformity insures consistent results
Cool edges provide no cross-linking Endothelium
Advantages of Accelerated CXL • Less Pain • Shorter downtime • Faster more controlled procedure → less complications • Reduced loss of BSCVA • Faster stabilization → Earlier intraocular compensation (custom phakic IOL’s) • More predictable refractive outcomes • Similar healing changes of stroma • Risk of endothelial cell damage: to be established • Failure to stop progression: to be established • New Scientific Evidence → new horizons • Thin corneas • Topo-guided CXL • LASIK Xtra
•
Greater patient / surgeon satisfaction
S.I.TRA.C Meeting 21-23 February 2013
PERCORSO FORMATIVO 1 ADVANCED INTERNATIONAL CXL COURSE
Thank you for attention
Dr. Lovisolo has no proprietary or financial interest in any device or product mentioned in this presentation
Carlo F. Lovisolo, MD Quattroelle Custom Eye Centers Milan Italy