April 2011

After last night’s “A Current Affair” story about laser cataract surgery I expect to be fielding a lot of questions next week. 

The program, which was heavily promoted using a “sixty second surgery” sound bite,  reported the use of Alcon’s LenSx femtosecond laser for cataract surgery in Sydney. 

The ACA website promo says:

Cataract eye surgery is one of the most successful procedures in medicine, but imagine if the same procedure took a painless 60 seconds. A revolutionary new machine has just arrived in Australia to restore vision, which offers a non-invasive procedure and remarkable results with no pain.

Well, you need to keep using your imagination.

The story was misleading for a number of reasons. There has been no change in pain control, which remains excellent, and cataract surgery does not now take 60 seconds. In fact, using the new laser actually  takes longer because patients having femto cataract surgery are essentially having two procedures. First, they have the laser procedure in the laser room, which replaces the initial difficult but relatively brief part of the current standard operation. Then, because the laser doesn’t actually remove the cataract, they are moved to the operating theatre, where the cataract is removed and the lens implant inserted.  This second part remains essentially unchanged. The surgeon that was featured used a machine that has been around for 7 years to remove the cataract, and as you could see it still works very well.  

Does the new laser make the procedure safer, as the ACA surgeon said? Well, it might. And that’s as far as you can go at present. There is simply no evidence yet that femto surgery is safer.  There have been about a thousand cataract operations using the femtosecond laser worldwide, and as the infection rate using the current standard technique is less than 1/1000 we are nowhere near seeing the numbers required to compare one technique to another.  The marketers tell us that the wounds created are more precise than those made with a knife, and that this will lead to reduced wound leakage. Since wound leakage is a risk factor for infection, they suggest that the infection risk will be lower. Is there any evidence to support this? Not yet. It is speculation.

As I said in my previous blog the new technology is certainly very exciting.  So far it looks like the main benefit will be more accurate lens position, and this may mean less patients needing distance glasses after surgery. It may have the power to make a wonderful, miraculous operation even better. But we need to be very careful of crafty spin.

The American Society of Cataract and Refractive Surgery (ASCRS) conference was in San Diego last week, and most of the hype and excitement was centred around Femtosecond Laser-Assisted Cataract Surgery. Although only one machine is in commercial use in the USA (the LenSx), the marketing drive is in full swing and this is set to continue, as three other companies are readying to launch their machines over the next 12 months (OptiMedica’s Catalys, Lensar, and Technolas Customlens from Germany). Alcon recently bought LenSx for more than $360 million, so it’s unsurprising that they’re trying to push home the advantage of being first on the market.

I went to an event in San Diego presented by Alcon in which a packed theatre was wowed with a laser light show before being shown videos of the femto in action, with commentary from five prominent American surgeons. Although only two of the five surgeons have the laser in their operating theatres and fewer than 1000 patients worldwide have had the surgery, the consensus was that this is the biggest advance in the safety and efficacy of cataract surgery to come around in 2 decades. Strong stuff. Are they right?

Well, it’s simply way too early to judge. Certainly, the technology in the femto systems is amazing. They can cut extremely precise wounds, and cut perfect repeatable circular openings in the 20-micron anterior lens capsule (capsulotomy) every time. This precision, greater than can be performed by any surgeon’s hands, may ultimately prove to improve visual outcomes, but so far there is no direct evidence that this is the case. Likewise, the implications for safety are all indirect and speculative, and unproven.

Femtosecond lasers were introduced into refractive surgery around 10 years ago. After a decade, they still haven’t supplanted steel blades for all patients or all surgeons, despite their stated benefits. It’s now recognized that in some settings they are safer and reduce complications, but that they also introduce different complications. Femto technology is not cheap to purchase (around $500 000 up front for the machine) or to use (companies charge a fee-per-use, known as a “click fee”), and they take significantly longer. All of this means that femto-assisted cataract surgery will be substantially more expensive than current state-of-the-art cataract surgery. 

Will it be safer? In the hands of an experienced surgeon modern cataract surgery is amongst the safest medical interventions ever devised. It will take some time and a lot of data before anyone can say that the supposed advantages of femtosecond laser cataract surgery are real, rather than imagined. There is no femto cataract laser in Queensland yet. I’m looking forward to seeing more data on safety and efficacy, and to trialling the femto when it becomes available in Brisbane.