Microincision Cataract Surgery with a Scleral Approach Jean Luc Febbraro MD Marlene Ostendorff MD Damien Gatinel MD Rothschild Foundation Paris France No financial interest

Purpose To evaluate the  safety, the feasibility and the  effectiveness of scleral microincision cataract surgery (S-MICS).    Why S-MICS? To improve the wound integrity and safety of microincision: scleral incisions heal faster than corneal incision. (Ernest and Neuhann) 1,2,3 ASCRS 09 JL Febbraro MD

Materials & Methods 48 eyes 1.8 mm S-MICS on steep axis Topical anesthesia Hydrophilic acrylic IOL Wound assisted injection ASCRS 09 JL Febbraro MD

Materials & Methods S-MICS Location Size Knife 1.5 to 2 mm behind the limbus Conjunctival miniperitomy (>2mm) Two plane square incision Size 1,8 x 1,8 mm Scleral tunnel Knife Trapezoidal 1.6 X 1.8 mm metal blade ASCRS 09 JL Febbraro MD

Results Efficiency Limited intraoperative bleeding (small conjunctival and scleral incisions) Low incidence of chemosis (2 cases) Self sealing in most cases (wound hydration in 4 cases) No postoperative leakage or hyphema Fast visual recovery: 75% > 20/40 by 3 days po. ASCRS 09 JL Febbraro MD

Results Keratometric astigmatism Pre and postoperative keratometry S-MICS n:48 Mean Preop Astig. Mean Postop Astig K2-K1 0.59 +/- 0,35 D 0,65 +/- 0,35 D S-MICS n:48 K1 K2 Preop 43,30 +/- 1,43 D 43,86 +/- 1,48 D Postop (3 months) 43,28 +/- 1,48 D 43,90 +/- 1,50 D ASCRS 09 JL Febbraro MD

Discussion Sub 2-mm microincision cataract surgery has proven to be effective and is gaining popularity worldwide.4,5 Sub 2-mm corneal incisions are not necessarily more stable. Wound architecture errors, intraoperative stretching and ovalisation of clear corneal MICS may compromise wound self sealing and healing properties. ASCRS 09 JL Febbraro MD

Discussion In the 1990s Ernest cadavers and animal eyes studies have shown that 3 key parameters could influence wound construction 1,2,3: Geometry: square incisions provide better stability, regardless of location. Tissue properties: elastin enables tissue to return to original configuration when stretched. Histology: fibroblasts speed wound healing. ASCRS 09 JL Febbraro MD

Discussion Clear corneal MICS is efficient but wound stretching or ovalisation may occur in spite of appropriate incision construction. Scleral MICS has the following advantages: Allows for a 1.8 x 1.8-mm square scleral tunnel, more resistant to intraoperative stretching. Optimum location with ideal tissue and histological properties to optimise self sealing and speed wound healing. More flexible and forgiving in wound construction errors, enlargement or IOL exchange. ASCRS 09 JL Febbraro MD

Conclusion The scleral approach for microincision cataract surgery (S-MICS) is an efficient and safe alternative to clear corneal microincision. It provides satisfactory self sealing and healing properties with very limited cons (bleeding and chemosis). It provides flexibility in case of wound extension, IOL exchange and forgives wound architecture errors. ASCRS 09 JL Febbraro MD

References Ernest P.H., Lavery K.T., Kiessling L.A. Relative Strength of Scleral Corneal Incisions Constructed in Cadavers Eyes. J Cataract Refract Surg. 1994;20:84-88 Ernest P.H., Neuhann T. Posterior Limbal Incision. J Cataract Refract Surg. 1996;22:78-84 Ernest P.H. et al. Is There a Difference in Incision Healing Based on Location? J Cataract Refract Surg. 1998;24:482-486 Alio JL et al. Outcomes of Microincision Cataract Surgery Versus Coaxial Phacoemulsification. Ophthalmology. 2005;112:1997-2003 Alio JL et al. Visual Outcomes of Microincision Cataract with Implantation of Acry Smart Lens. J Cataract Refract Surg. 2005;31:1549-1556 ASCRS 09 JL Febbraro MD