Eyeworld

EW NEWS & OPINION 20 Two-year follow-up of femtosecond intrastromal presbyopic laser treatments Mike P. Holzer, M.D., F.E.B.O., M. Tomalla, M.D., T.H. Neuhann, M.D., M.C. Knorz, M.D. The femtosecond laser-based in- trastromal correction of presbyopia (INTRACOR, Technolas Perfect Vi- sion, Munich, Germany) is being in- vestigated in a prospective, German multicenter study. Sixty-three pa- tients (mean age 55 years) were en- rolled in four centers. During the fast and painless procedure, five corneal intrastromal ring cuts are created. Most patients are achieving a 4-5 line improvement in near vi- sion, and about 80% are able to read without glasses under good light conditions. Mean logMAR UCNVA improved significantly from 0.72 (20/100) at baseline to 0.20 (20/30) at 24 months. The results were simi- lar for DCNVA. Mean logMAR BCDVA showed no significant change from baseline to 24 months. Refractive analysis revealed a small myopic shift (0.4 D), which is why it is recommended to be performed in slightly hyperopic patients. Collagen crosslinking (CXL) for keratoconus with simultaneous topography-guided photorefrac- tive keratectomy (TG-PRK) Simon P. Holland, M.B., F.R.C.S.C., David T. Lin, M.D., F.R.C.S.C. We evaluated early results of simul- taneous TG-PRK with collagen crosslinking for efficacy and safety. One hundred five eyes of 72 patients with contact lens intolerant kerato- conus (KC) underwent transepithe- lial TG-PRK with a WaveLight Allegretto Laser (Alcon, Fort Worth, Texas) with simultaneous CXL. The limit of refractive correction was es- timated on residual stromal depth of 320 microns. Thirty-two eyes completed 1- year of follow-up with 70% having UCVA of 20/40 or better, with all achieving BSCVA of 20/40 or better. Four eyes lost two lines of BSCVA and six gained two or more lines. Only 5/22 were using refractive cor- rection at 1 year with symptom im- provement in 19/22. Complications included a delay in epithelial heal- ing beyond 1 week in four, and one developed herpetic keratitis, with all five recovering pre-op BSCVA. Conclusions: Simultaneous to- pography-guided PRK with CXL of- fers promising early results for contact lens intolerant KC. Im- proved uncorrected vision was ob- tained in 70%, but the extent of refractive correction is limited by low pachymetry in keratoconus. Matched comparison of three for- mulae for calculating IOL power in eyes with long axial lengths Leonard Yuen, M.D., Wei-Han Chua, F.R.C.S.Ed.(Ophth.) Our prospective, randomized study aimed to compare three readily available IOL power calculation formulae (SRK/T, Hoffer Q, and Holladay II) to achieve intended post-op target refraction in eyes with axial lengths >25 mm undergoing phacoemulsification with an IOL implant. One hundred forty-four eyes were recruited with a mean axial length of 27.35+/–1.92 mm (range 25.01-33.53 mm). The pri- mary outcome measures, post-op mean absolute error (MAE), at post- op month 3 for SRK/T, Hoffer Q, and Holladay II were +0.20+/–0.80 D, +0.54+/–0.81 D, and +0.61+/–0.68 D, respectively (p<0.001). The overall predictability for achieving within 0.25 D, 0.5 D, and 1.0 D of target was highest using SRK/T (36.4%, 65.7%, and 89.3%, respectively). Our study suggests that SRK/T is the most accurate at achieving target re- fraction for axial lengths between 25 and 30 mm. For AL >30 mm, all three formulae frequently produced hyperopic surprises. Evaluation of computer-based visual cortex training after monofocal, multifocal, and accommodating IOL implantation George O. Waring IV, M.D., John D. Hunkeler, M.D., Richard L. Lindstrom, M.D., Jay S. Pepose, M.D., Ph.D. Dr. Waring and colleagues con- ducted a prospective, multicenter, controlled pilot study to evaluate 62 eyes using computer-based primary cortex vision training (RevitalVision, Lawrence, Kan.) after implantation of aspheric monofocal, multifocal, and accommodative IOLs. At baseline, the investigators measured uncorrected distance (UCDA), near visual acuities (UCNA), and the distance and near contrast sensitivity values. Baseline data, obtained 1 month after IOL implantation, were compared with data after 20 sessions of neurocorti- cal training over a 2-month period. Comparison of pre-op and post- op UCDA and UCNA revealed im- provement of more than one line of uncorrected distance vision and just less than one line of uncorrected near acuity, respectively. The dis- tance contrast sensitivity improved 170% and the near contrast sensitiv- ity improved 100%. The differences were statistically significant for com- parisons at all time points. To control for normal neuroad- aptation, investigators compared the results in the study group to a group of patients implanted with IOLs who did not undergo cortical training and found a statistically significant difference in UCDA with a differ- ence approaching statistical signifi- cance in UCNA. EW October 2011 ASCRS Best papers of session

• Cover