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Removing floaters with Laser

Removing floaters with Laser

Large series finds floater removal usually effective with very few complications

Many vitreo-retinal surgeons avoid “floater” surgery because the risks of vitrectomy (extraction of the vitreous by surgery) often seem to outweigh the benefit of removing what are usually thought of as minor visual disturbances. “Floaters” or “Mouches Volantes” are small dark spots, patches or thread-like structures in the field of view, which shift in a characteristically scurrying manner along with the line of sight, performing slow-swinging movements around a basic position.

Even LASER VITREOLYSIS is suspect, regarding Paul Singh MD in the ASCRS 2017. Many surgeons express concern that laser vitreolysis may not be effective, and could produce inflammation or retinal detachment based on few published cases.

 

The question from patients is always the same: “is it safe?”. In Dr. Singh´s experience, with more than 1200 cases, the answer is unequivocally “YES!”. Nd: YAG laser vitreolysis using pulse power double or more those typical for posterior capsulotomy not only is safe, but it is effective in relieving patients´ of visually debilitating symptoms due to floaters.

Floaters often interfere with reading, driving, watching TV and other daily activities, and can be visually disabling. On average, patients would risk more to avoid them, including possible blindness or reduced lifespan, than they would to rid themselves of diabetes or HIV, according to one large study (Am J Ophthalmol. 2011; 152(1): 60-65). While this finding may or may not hold in real life, average ophthalmologysts tend to underestimate the impact of floaters on patients´lives.

1272 Cases, 10 Complications

Dr. Singh heads Eye Centres of Racine and Kenosha, Wisconsin, USA. He presented results from 1272 consecutive laser vitreolysis cases in 680 patients treated with an ULTRA Q Reflex Nd:YAG laser (Ellex), using a Sing Mid-Vitreous lens (Volk) with an adjustable depth of focus extending from posterior lens surface to the retina. All patients were seen at 1 month, 3 months and 1 year after the procedure, and 146 were followed for at least 4 years. Optical Coherence Tomography (OCT) from the macula was performed after the procedure.

An average 562 laser pulses were fired per treatment session, and a mean of 2,4 sessions were required per case. Laser pulse energy ranged from 2,5 mJ for treatment close to the phakic lens of retina, up to 12 mJ in the mid-vitreous, though most work was done in the 4,0-6,0 mJ range.

The laser pulse vaporizes target tissue and creates an acoustic shock wave travelling back toward the source, but wave depth does not increase linearly with power. A 1,0 mJ pulse creates a 110 micron shock wave, while a 10,0 mJ increases it to only 220 microns, making 4,0 to 6,0 mJ a good compromise of power and precision with a shock wave of about 150 microns. The energy beam is also truncated, which allows for less energy needed to cause a plasma spark. The pulse is also very short, about four nanoseconds, which means energy is dispersed before the next shot is fired and does not build up.

Results are generally better when the floaters were isolated Weiss rings, which required fewer pulses and visits, or large amorphous clouds in the mid vitreous. Small floaters are more difficult to visualize and treat, and patients were generally less satisfied with the results.

Complications registered in Dr. Singh´s series included seven intraocular pressure spikes, two phakic lens hits, and one retinal haemorrhage, for a total adverse event rato of 0,8%. Six IOP spike patients were resolved with temporal topical drug treatment, one with permanent drop treatment.One phakic lens hit required cataract surgery, and the other is still under observation. The retinal haemorrhage resolved in 3 months with no long term negative effects.

The procedure is safe, painless, effective and minimally invasive. There are no post-laser activity restrictions, and patients are highly satisfied. The use of the proper technique and technology is the key for the successful outcome of this amazing laser procedure to relieve the feeling of annoying floaters.

Yours Dr. med. Diego Richards

Ophthalmologist