Femto for Fuchs

Cataract surgery is a very safe procedure – unless you have a pre-existing ophthalmic condition like Fuchs dystrophy. In this degenerative disease, cells in the corneal endothelium slowly die off, causing the cornea to swell and become cloudy, distorting the patient’s vision. Unsurprisingly, Fuchs dystrophy patients are susceptible to further complications during surgery (1) and, as a result, many of these patients may be too frightened to go ahead.

But we have another option. In my experience, femtosecond laser-assisted cataract surgery (FLACS) can help Fuchs dystrophy patients achieve very good visual outcomes, as well as quicker overall recovery times. In some cases, FLACS can even prevent the possibility of corneal transplantation at a later date.

So why FLACS? There are two main reasons. Firstly, the laser can perform three crucial steps in cataract surgery – corneal incisions, capsulorhexis and fragmentation of the nucleus – without the need for intraocular manipulation (2). Secondly, FLACS reduces exposure to phacoemulsification – the high-level energy of which poses an increased risk of endothelial damage, which is of the greatest concern when it comes to treating Fuchs Dystrophy patients (2, 3).

In our hospital, we use LENSAR with Streamline IV (Orlando, USA), which automatically categorizes cataract density on a scale from 1 to 5 and applies a pre-programmed fragmentation pattern based on my surgical preferences, resulting in precise laser placement and lenticular fragmentation. Most importantly, it causes less damage to the endothelium. We also use an additional OVD during lens aspiration to protect the endothelium, which can, in turn, prevent the need for a corneal transplant.

Of course, there is no guarantee that a patient will not suffer corneal decompensation, regardless of the technique used. I have treated several patients with different methods in each eye, including a case where corneal decompensation occurred after I had performed manual surgery. In this case, I performed a DMEK. Comparatively, where the endothelial damage was milder (in the patient’s left eye), I was able to use FLACS to perform cataract surgery on its own. Promisingly, there was no decompensation. One thing I have learned with FLACS for Fuchs dystrophy patients is that, if the cell density is reduced, there may be a need to increase the energy for the capsulotomy (I usually increase it by around one third as the cornea can already be reasonably cloudy and dense).

In conclusion, standard surgical procedures – particularly manual techniques – increase the risk of further complications or progress the symptoms of Fuchs dystrophy. They also carry the major disadvantage of increasing the amount of energy delivered to the eye during lens fragmentation, which results in endothelial cell damage. FLACS provides us with a safe, viable alternative that combats some of these issues – and that’s why it is (and will remain) my preferred method of cataract extraction for Fuchs dystrophy patients.