1. So-Hyang Chung, MD, PhD, Choun-Ki Joo, MD, PhD Department of Ophthalmology and Visual Science, College of Medicine, The Catholic University of Korea, Seoul, Korea * Authors have no financial interests.

2. 1.Reduction of incision size 2.Decreased energy and increased efficiency 3.Less endothelial cell loss * Advancement of Cataract surgery technique 1.Reduce the amount of phacoemulsification energy 2.Increase efficiency 3.Allow cataract surgery through micro coaxial incision. * OZiL torsional handpiece > traditional handpiece

3. 2.2mm micro coaxial incision (32 eyes) 0.9mm mini-flared 45- degree bevel Kelman ABS tip 2.8mm Standard clear corneal incision (28 eyes) 0.9mm micro 45 degree bevel Kelman ABS tip Versus Our study was designed to compare torsional ultrasound systems with same degree tips between standard 2.8 mm standard clear corneal incisions and 2.2 mm micro coaxial incisions.

4. Retrospective study Duration : April 2008 ~ September 2008 Patients : 60 eyes patients 1.Operated by one surgeon 2.Cataracts of similar density (LOCS III classification –grade III, IV) Exclusion criteria 1. Underlying systemic disease or ocular disease (DM, Corneal surface irregularity, high myopia, RD, glaucoma) 2. Age > 80yrs

5.  Parameters  Intra-operative parameters ▪ Mean cumulative dissipated energy (CDE) ▪ Total balanced salt solutions (BSS)  Post-operative parameters ▪ Central corneal thickness (CCT) at postoperative 1 day ▪ Endothelial cell loss (ECL) at postoperative 6 months All cases were uncomplicated. 5 In the bag IOL implantation 6 Sutureless technique 2 3 Temporal clear corneal incision About 6.0mm CCC diameter 1 patients selection 4 Phacoemuls -ification

6. Parameter Mean + SD 2.2mm incision2.8mm incisionP-value Intra-operative CDE6.18±3.5410.38±4.610.038 BSS used72.06±24.195.23±35.50.307 Paired T-test P<0.05 Parameter Mean + SD 2.2mm incision2.8mm incisionP-value Post -operative Central corneal thickness(μm) Pre-operative554.17±35.8534.86±31.70.091 POD #1622.05±71.7604.72±57.20.479 Change67.88±75.0669.86±55.870.985 Endothelial cell count (cells/mm 2 ) Pre-operative2494±3592683±3250.402 POD#6mon2185±4412188±4520.346 Change-309±423-495±4860.048 Intra-operative and post-operative characters.

7. 2.2 mm micro coaxial incision2.8 mm standard incision CDE showed positive correlation with BSS use (P<0.001, R 2 =0.302).

8. 2.2mm group2.8mm group CDE showed positive correlation with ECL and CCT change (P=0.006, R 2 =0.345, P=0.22, R 2 =0.346).

9. 2.2 mm micro coaxial incision2.8 mm standard incision BSS use showed positive correlation with ECL (P=0.012, R 2 =0.283).

10.  CDE and endothelial cell loss were lower in the micro coaxial incision group (P<0.05).  Better cutting efficiency with a mini-flared 45-degree tip may reflect its better holding force factor of a mini-flared 45-degree tip in micro coaxial incision.  Postoperative endothelial cells loss correlated with intra-operative CDE and BSS use.

11.  Phacoemulsification (using the OZil torsional handpiece) through 2.2 mm micro coaxial incisions showed less total energy use and less endothelial cell loss than 2.8 mm standard incisions.  Torsional ultrasound systems through 2.2 mm micro coaxial incisions were safe and effective in phacoemulsification!