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What do the recent technological advancements for femto cataract surgery mean? by Robert Cionni, MD Innovations in femtosecond technology Surgical outcomes of laser cataract surgery have improved significantly with the latest technology and development of modified techniques. I have been using the LenSx Laser (Alcon, Fort Worth, Texas) since February 2011. In a study of 3,355 consecutive cataract/refractive lens exchange procedures performed with the LenSx Laser between April 2012 and October 2014, a break in the capsule rim was identified in 7 (0.21%) eyes. 1 This occurred during phacoemul- sification in 6 eyes and during irrigation/aspiration in 1 eye. The tear extended to the posterior capsule in 2 eyes, and 1 of these eyes required anterior vitrectomy. Sulcus IOL implanta- tion was safely performed in both cases. In 2 cases, the tear ex- tended to the equator without posterior capsule involvement or vitreous loss, and in-the-bag IOL implantation was success- fully performed with the haptics aligned away from the laser. All tears were observed after phacoemulsification or cortical removal in cases with no predisposing conditions recorded. In my practice, for routine cases, capsular tear rates are less than 1% in femtosecond cases compared with 2% to 3% for manual cases. With a femtosecond-made capsulotomy, I know the anterior capsular opening will be centered and about 5.2 mm every time. With a manual technique, I may think I'm tearing a 5.5-mm capsulotomy, but by the time I'm done, the capsulotomy may actually be a little larger or a little smaller and not perfectly centered. I think we get tears in manual cases because we nick an edge with the phaco tip or with a second instrument as we are a little less certain of the size of the opening and exactly where those edges are. In the manual cases, I use an optical zone marker to make an indentation on the corneal epithelium before I do my man- ual capsulotomy. Due to the effect of corneal magnification, if I stay inside that ring, I usually end up with about a 5.25- mm capsulotomy, but it can still vary depending on chamber depth and corneal curvature. It can also vary because I have to do it manually. I've performed a lot of cataract surgery, and I typically achieve a fairly round, nicely sized capsulotomy. However, it's not every time. With the laser, it's every time. The Variable Beam Profile is unique to the LenSx Laser. Most lasers were designed either for cornea work or for capsule work, meaning that the laser beams are oriented or focused in such a way as to work deeper in the eye or, alternatively, more anteriorly on the surface of the eye. The innovation in the LenSx Laser is that it has a variable beam, such that when it's working at the corneal surface, it focuses differently, from different angles, than when it's focusing deeper. So it behaves both like a laser that was made to work on the lens and like a laser that was made to work on the cornea. The LenSx Laser creates beautiful capsulotomy incisions, beautiful lens chop incisions, and beautiful corneal incisions. A recent study has found that this procedure is efficient and less damaging than manual procedures. 2 The study includ- ed 60 eyes of 60 patients who underwent clear corneal incision cataract surgery; in 30 eyes, the incision was performed with the LenSx Laser, and in 30 eyes, the incision was performed manually. In the eyes in the LenSx Laser group, there was less central endothelial cell loss, less increase in corneal thickness at the incision site, and better tunnel morphology than in eyes in the manual group. Combined with the Variable Beam Profile, the SoftFit Patient Interface helps the precision of the platform by providing fixation with very minimal corneal distortion. The SoftFit Patient Interface incorporates a soft hydrogel lens in the interface so that the interface conforms to the cornea, thereby markedly minimizing the risk of corneal folds and reducing the scattering of that energy. The result is a smooth and complete capsulotomy nearly all of the time with a much lower risk of having tags or rough edges. It also holds the eye with an appropriate amount of vacuum to prevent eye move- ments that can lead to misguided energy delivery as can be seen more frequently in other laser platforms that don't fixate the eye. 2 Using proprietary hydrogel technology, the SoftFit Patient Interface conforms to the patient's natural corneal curvature for precise docking. For important product information, please see page 8.

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