FEMTOSECOND LASER ASSISTED SURGERY

Femtosecond laser-assisted cataract surgery helps provide more predictable outcomes and reduces the amount of manual steps the surgeon has to carry out, Lucio Buratto MD told the Joint Irish and UKISCRS Refractive Surgery Meeting in Dublin. Dr Buratto, Milan, Italy, spoke to the meeting about his experiences with this relatively new form of surgery. Looking back to 1978, Dr Buratto said the question at the time was: 'Is phacoemulsification the future of cataract surgery?' Or was it simply a more complex surgery from the technological, organisational and cost points of view? “Over the last 30 years, more than 50 million eyes have been subjected to phaco surgery so the answer was yes,†he said. Ophthalmic surgeons are now faced with a similar question in 2012 about whether femtosecond laser is the future of cataract surgery, or is it simply the installation of a more sophisticated, expensive instrument in the operating room? “I don’t know the answer for sure but in my opinion the answer is yes, laser is the future for cataract surgery, for certain stages,†he told the meeting. Explaining the role of the femtosecond laser in cataract surgery he stressed that the femtosecond laser does not aim to replace phacoemulsification or remove the cataract with a laser phaco. Instead, femtosecond laser aims to replace some of the manual procedures that are dependent on the surgeon’s skill with some procedures that are controlled by a computer, he elaborated. Today the femtosecond laser can perform a capsulotomy, fragmentation of the nucleus, corneal incisions and, if needed, relaxing incisions.

Looking at the technology itself, he said there are currently four companies providing femtosecond laser technology, three American and one European. Dr Buratto gave a positive report on the LenSx Alcon machine having now treated over 400 eyes with the device. Looking at the benefits of femtosecond laser in performing a capsulotomy, Dr Buratto said it is very precise in terms of diameter, position and centring. It also gives a perfectly circular shape. Overall, he said there are many key benefits of using the femtosecond laser in cataract surgery. These include less intraocular manipulation, lower stress on the incision, fewer instruments enter the eye and less intraocular ‘work’. There is also lower use of intraocular liquids and a reduction in surgical time (but perhaps an extension of overall time, especially during the learning curve). “The main incision can be programmed very precisely in width, shape position and depth. A good incision means better standardisation of the refractive result, a better ratio between the phaco tip and the incision, and better closure of the incision at the end of surgery,†Dr Buratto reported.

Optimum refractive results

The optimal results in the correction of refractive defects on the cornea with laser surgery (femto and excimer) depend on reduced surgeon involvement, said Dr Buratto. He said the surgeon controls the femtosecond laser and the lamellar cut for LASIK is completely automated. The surgeon follows with the excimer laser and the refractive treatment is completely automated. “Yesterday LASIK was a surgical procedure performed by the surgeon, while today LASIK is a surgical procedure performed predominantly by the laser machine! Likewise, yesterday phaco was a surgical procedure performed by the surgeon while today we have a partial reduction of the surgeon’s involvement and a new surgical assistant appears: the laser technician. However, phacoemulsification is still required,†he said.

Briefly discussing the indications for femtosecond laser-assisted cataract surgery, he said a fully dilated pupil is needed (≥ 6.0mm) as is a relatively clear cornea. This form of surgery is not without difficulties, Dr Buratto said. Docking may be uncomfortable in small eyes and conjunctival redness may occur. Capsulotomy diameter can only be set to the extent the pupil dilates. When the laser is delivered too close to the iris it can stimulate miosis. One must also exercise caution when learning the laser technique and may need to make slight adjustments to phaco technique intraoperatively. Overall however, Dr Buratto maintained the advantages far outweigh the negatives.