Prospective Study Comparing Outcomes of Torsional versus Traditional Phacoemulsification Systems on Dense Cataracts Bonnie An Henderson MD, Kelly J Grimes MS Ophthalmic Consultants of Boston Harvard Medical School Financial Disclosure Henderson: Alcon labs- grant support, speaker’s bureau ISTA pharmaceuticals- grant support Grimes: None

Purpose To compare the post-operative surgical outcomes of torsional (Alcon Infiniti™ Ozil) and traditional (Bausch and Lomb Millennium™) phacoemulsification systems on different grades of cataracts

Methods Preoperatively: Patients’ standard preoperative examination and measurements were recorded. Additionally, preoperative central corneal pachymetry was recorded. All cataracts were graded by the LOCS classification by one examiner (BAH) Only cataracts that were NO4NC4 or higher were considered “dense” and included in the subgroup

Methods Patients were randomized to receive cataract surgery using either the Alcon Infiniti™ OZil machine or the B&L Millennium™ machine. Surgical technique, instruments, type of viscoelastic, and type of IOL were held constant for all surgeries in the study

Methods Intraoperatively: total surgical time, phaco time, ultrasound time and energy, total BSS, phaco BSS were recorded Patients with previous corneal disease were excluded from the study Patients with an IOP > 26 on postoperative day 1 were excluded from analysis (due to effect of high IOP and causal relationship to corneal edema)

Methods Patients were followed up at one day, one week, and one month post-operatively. Recorded at each visit: vision, intraocular pressure corneal thickness anterior chamber inflammation corneal edema All patients received the same type and quantity of postoperative drops Data was analyzed in two groups: 1) all lens densities 2) a sub-group of dense lens cataract patients (NO4, NC4 or denser).

Results 127 patients (69 B & L, 58 Alcon) 36 dense lens patients (21 B & L, 15 Alcon) 6 patients excluded due to IOP > 26 on postoperative day 1

Results – All Cases Alcon (58) B&L (69) P-value Pachymetry (post-op Δ in µ) POD 1 20.62 55.59 0.0014 POW 1 8.14 14.37 0.301 POM 1 -7.57 -1.13 0.182 K Edema* 1.71 2.74 0.0021 0.09 0.46 0.017 0.00 0.04 N/A AC Cells* 4.95 4.90 0.69 1.21 2.13 0.0009 0.13 0.68 * numerical values represent physician's quantitative estimation of corneal edema/anterior chamber inflammation respectively as follows: NL = 0, rare/trace = 1, occasional = 2, 0.5 = 3, 1+ = 4, 2+ = 5, 3+ = 6, 4+ =7

Results – Dense Lens Cases Alcon (15) B&L (21) P-value Pachymetry (post-op Δ in µ) POD 1 25.56 92.76 0.016 POW 1 12.92 21.30 0.455 POM 1 -7.25 6.38 0.22 K Edema* 2.63 3.47 0.2302 0.63 0.06 0.1064 0.00 0.05 N/A AC Cells* 5.19 5.06 1.56 2.50 0.21 0.048 0.24 * numerical values represent physician's quantitative estimation of corneal edema/anterior chamber inflammation respectively as follows: NL = 0, rare/trace = 1, occasional = 2, 0.5 = 3, 1+ = 4, 2+ = 5, 3+ = 6, 4+ =7

Results – Dense Lens Cases Alcon B&L P-value All Cases Total Time (min) 9.24 9.98 0.1 Total BSS (cc) 190.5 222.3 0.0001 Phaco BSS (cc) 103.7 102.1 0.8449 Dense Lenses 10.06 10.95 0.45 228.8 225.0 0.78 96.4 104.7 0.38 * numerical values represent physician's quantitative estimation of corneal edema/anterior chamber inflammation respectively as follows: NL = 0, rare/trace = 1, occasional = 2, 0.5 = 3, 1+ = 4, 2+ = 5, 3+ = 6, 4+ =7

Conclusions Phacoemulsification cataract extraction on all lens types by torsional energy (Alcon Infiniti™ Ozil) resulted in significantly less corneal edema and thickness on post op day one compared to surgery by traditional ultrasound energy. There was significantly less corneal edema and anterior chamber inflammation at one week postoperatively with the torsional energy system.