Tuesday, August 8, 2017

Can we zap eye floaters away?

There it goes again: a big blob or “floater” drifting across my right eye. It’s not dangerous and it doesn’t hurt, but it sure is annoying having cloudy vision for a few seconds until the blob moves on. I have quite a few floaters — so do a lot of middle-agers — and I’ve learned to live with them, since there’s never been much in the way of treatment. But that may be changing.

Understanding floaters

Floaters are usually pieces of debris that come from the vitreous — a thick, jelly-like substance that fills the center of the eye. The vitreous attaches to the retina, which captures light and sends it to the brain via the optic nerve.

As we age, the vitreous starts to break apart and liquefy. Parts of the vitreous that don’t liquefy may wind up floating around, and can block light shining into the retina.

There are different types of floaters — spots, blobs, or strings. Many are small and don’t bother vision much.

A more prominent kind is called a Weiss ring. That’s what I have. It develops when the vitreous separates from the retina. A vitreous detachment doesn’t hurt or require treatment unless it tears the retina in the process. In that case, you may see a sudden shower of floaters, flashing lights, or a curtain coming over your vision, and you should call your doctor immediately. However, these symptoms often occur when the vitreous separates from the retina without a tear.

New evidence

A study published July 20, 2017, in JAMA Ophthalmology suggests that blasting Weiss ring floaters with a laser treatment called YAG vitreolysis may hold promise as a way to get rid of them. The procedure vaporizes floaters by heating them. “You can see the tissue vaporize and turn into gas bubbles,” notes Dr. Chirag Shah, a Boston ophthalmologist and one of the study authors.

Dr. Shah and Dr. Jeffrey Heier, a Harvard Medical School instructor in ophthalmology, randomly assigned 52 people with Weiss ring floaters to receive either YAG vitreolysis or a sham laser treatment. Six months later, 53% of patients in the YAG group reported significantly or completely improved symptoms, compared to zero percent in the sham group. “This was certainly encouraging, but we need more studies,” Dr. Shah says. Neither he nor Dr. Heier recommends YAG vitreolysis at this time.

Not ready for prime time

YAG vitreolysis is controversial, mainly because doctors have been offering it since the early 1990s without solid evidence about its safety and effectiveness. “Some providers charge out-of-pocket for YAG vitreolysis despite the limited proof that it works,” warns Dr. Shah.

The new study is important because it’s the first study of YAG vitreolysis in a randomized controlled trial, the gold standard of testing. The results are also encouraging because using the laser didn’t result in any tears or retinal damage within the study period.

Critics of the study say that the results may be skewed, since the doctors hand-selected only people with Weiss rings, as opposed to other types of floaters. Dr. Shah says they chose people who would best respond to the treatment. “Our results are not applicable to all patients,” he explains. “I encourage the retina community to study YAG vitreolysis in all floater types so we see how each type responds.

What should you do?

Until we have better evidence for YAG vitreolysis — and Dr. Shah says several new clinical trials are underway — there are only two treatment options for floaters.

One is a vitrectomy — surgical removal of the gel and the floaters from the back of the eye. It’s an effective surgery, but it has risks, including cataracts (cloudy lenses) and retinal detachment. It’s usually a last resort.

The other option is ignoring floaters. “In many cases, floaters associated with a posterior vitreous detachment become less noticeable or more tolerable over time, and can even disappear entirely,” says Dr. Heier.

I’m still waiting for my Weiss ring floater to disappear. If it doesn’t, I’ll live with it. But I’ll be curious to see if the next round of YAG vitreolysis studies adds more credibility to vaporizing floaters — an appealing thought when my floater drifts by.

The post Can we zap eye floaters away? appeared first on Harvard Health Blog.



From: Heidi Godman http://www.health.harvard.edu/blog/can-we-zap-eye-floaters-away-2017080812189

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