FEMTOSECOND LASER CATARACT SURGERY TECHNOLOGY

Experience to date suggests that the LensAR femtosecond laser system can provide greater precision in surgery than conventional phaco, which can translate into better visual outcomes for patients, Frank A Bucci Jr MD, Wilkes-Barre Pennsylvania, Us told the XXX Congress of the ESCRS.

“I think that the LensAR system, with its ergonomic design and imaging system, has made a significant contribution to femtosecond laser cataract surgery technology,†Dr Bucci said.

Dr Bucci noted that he and his associates have performed more than 6,000 free cataract surgeries over the last four years at the Eye institute of the sacred heart, a charity eye centre in Lima, Peru. hundreds of cases were performed with the LensAR laser in Lima during 2012.

One of the most frequently cited advantages of femtosecond laser cataract surgery is the precision it affords in the creation of the capsulorhexis, he noted. The rate at which he and his associates achieve free-floating capsulorhexis with the LensAR system has been greater than 98 per cent. Their results are similar to those achieved in the Asian Eye institute in Makati city, Philippines, where the surgeons achieved free-floating caps with the LensAR system in over 90 per cent of cases. The manifest refraction spherical equivalent at six months' follow-up was -0.21 D in 249 eyes that underwent capsulotomies with the femtosecond laser compared to +0.55 D in 123 eyes that underwent manual capsulotomies (P< 0.001).

The Philippines team also reported that procedures using femtosecond lasers involved less cumulative dissipated energy than those performed with conventional phacoemulsification, and that held true for all grades of cataract, Dr Bucci said. The same group also reported lower corneal endothelial cell loss after the femtosecond laser procedure than after conventional phaco, although it did not reach statistical significance (p > 0.09). Dr Bucci noted that the LensAR system is relatively small and compact and has a very ergonomic design. its retractable laser head can rotate 90 degrees, allowing the surgeon the choice of performing the procedure from the temporal or superior position. The LensAR docking system is a threepiece no-touch fluid-filled device that does not distort the cornea. its non-OCT 3-D biometry imaging system includes a highresolution scheimpflug infrared camera on a rotating platform.

Visualising surgery

Other features of the LensAR system include a scanning illumination beam that is confocal with the treatment laser, a down-the-pipe camera, which allows the surgeon to visualise the surgery as if through a surgical microscope, and calibration software which links all of the elements together into a single threedimensional system. The imaging system can detect and compensate for lens tilt when performing capsulorhexes. The laser also has several nucleus fragmentation patterns, including cubes, spheres and pies. however, removing the cortex takes practise, because the remnants do not present the usual leaflets that are easily accessed, but instead is thin with sticky properties and is often concealed behind the iris and capsular edge.