1. Custom Topographic Neutralizing Technique (TNT) with Topographically-Guided (TG) laser to correct complications David T.C Lin Simon Holland ASCRS 2010 Boston, MA *no financial interests

2. Aim  Evaluate custom Topographic Neutralizing Technique (TNT) using the Allegretto Wavelight laser  Aberrated eyes including enlargement of small optical zones (OZ) and decentered ablation

3. Methods  Retrospective consecutive case series  53 eyes: decentered ablations  62 eyes: symptomatic small optical zones, previously treated laser refractive surgery underwent topography-guided retreatment with Wavelight laser  Follow-up: 1, 3, and 6 months  Patient evaluation: symptom score, safety

4. Results  Results at six months and one year: UCVA, BSCVA, topography, and predictability of centration from pupil center (0.92-0.30mm)  24% of eyes ≥1 lines; 71% no change  53 eyes with small optical zones: increase central monodioptric optical zone, 3.9- 5.6mm  All eyes improved astigmatism, range 1.25- 6.75D  Symptoms improved or resolved in 82% (n=47, DA and OZ), 18% no change

5. TG LASIK Retreatment for OZ Enlargement  6 years post LASIK (-4 D)  Pre-op : +1.006mths post-op  BSCVA : 20/20UCVA : 20/30  TGL Tx: +0.76Rx :+0.50-0.50x90 20/20

6. TG LASIK Retreatment for OZ Enlargement  9 years post LASIK (-5.25-2.25x2)  Pre-op : -0.50-0.50x756 month pos-top  BSCVA : 20/25UCVA : 20/25-  TGL Tx: -0.87Rx :-0.25-0.25x60 20/20

7. TG LASIK Retreatment for OZ Enlargement  5.5 years post LASIK (-5.25-1.00x10)  Pre-op : -0.75-0.25x56 months post-op  BSCVA : 20/20UCVA : 20/20  TGL Tx: -0.99-0.24x180Rx : -0.25 20/20

8. TG LASIK Retreatment for Decentration  5 years post LASIK (-9.50-1.25x75)  Pre-op : -1.25-0.75x703 months post-op  BSCVA : 20/20UCVA : 20/20  TGL Tx: -1.71-0.48x88Rx : -0.25 20/20

9. TG LASIK Retreatment for Decentration  3 years post LASIK (-9.00-0.50x180)  Pre-op : -1.7522 months post-op  BSCVA : 20/20UCVA : 20/20  TGL Tx: -2.19-0.24x170Rx : +0.25 20/20

10. TG LASIK Retreatment for Decentration  11 years post LASIK (-3.75)  Pre-op : +1.501 month pos-top  BSCVA : 20/250UCVA : 20/25  TGL Tx: +1.53Rx : -0.50-0.25x45 20/20

11. Discussion: Challenges in Treating Irregular Astigmatism  Treatment planning difficult  Induced refractive error - Topographic Neutralization method (TNT) can usually avoid need for 2 stage treatment  Patients need to have realistic expectations  Presently may be best surgical option for symptomatic patients with DA and small OZ (e.g. when poor wavefront capture )

12. Conclusions  Topographic-guided ablation using the Allegretto Wavelight laser is safe and effective in the management of highly aberrated corneas after laser refractive surgery  Treatment planning is challenging (predictability, Q factor correction), but can be improved by the Topographic Neutralization Technique