Nd:YAG laser treatment effective for vitreous floaters
Study showed similar success in phakic and pseudophakic eyes.
FORT MYERS, Fla. Nd:YAG laser treatment for symptomatic vitreous floaters was efficacious in a retrospective study done here.
Laser treatment in my hands was efficacious at a rate of about 85%. Phakic and pseudophakic eyes can be treated with equal success, said Scott Geller, MD, in practice here.
Dr. Geller and Lijun Xu, MD, conducted a retrospective study of 112 consecutive eyes in 95 patients between 1995 and 1998. Included were patients with 6-month symptomatic persistence of vitreous floaters and no improvement noted during that time. The study found that increasing the power and number of pulses does not necessarily improve the outcome.
I have done about 1,500 cases similar to this. When compared with normal eyes, comorbid eyes did have less improvement but still had a statistically significant improvement rate, he said.
Researchers developed criteria to judge patients vitreous floaters; +1 floaters were considered mild, +2 floaters were moderate and +3 floaters were considered severe.
We excluded patients with advanced diabetic retinopathy, retinal or vitreous hemorrhage and acute or chronic uveitis. Severe floaters consisted of posterior opacities or dense fibrillar degeneration in the anterior vitreous, Dr. Geller said.
The LASAG Microruptor II was used, with power settings between 1.5 mJ and 19.9 mJ per pulse. The average power was 7.6 mJ, and the researchers reported minimal problems associated with the cases. Patients were treated in five- or six-shot bursts.
The treatment goal was the total breakup of posterior hyaline opacities or the breakup of mid- and anterior-fibrillar clumps and their supporting strands, he said. He showed the audience a video of a large dense degenerative mass in the anterior vitreous, explaining that a case like that takes about 300 to 600 pulses.
Total subjective resolution of central visual obscuration occurred in 37% of patients, significant improvement in 28%, moderate improvement in 18%. That gives us a percentage improvement rate of about 85% total in the patients, he said.
A nonparametric analysis determined if there were statistically significant differences between the result groups and the eye groups.
We divided the patients into pretreatment and post-treatment groups. These groups were then subdivided into phakic eyes and pseudophakic eyes, healthy eyes and comorbid eyes, he said.
Dr. Geller noted that the average number of laser shots used did not differ much among the groups nor did average total power.
More power for more severe cases
There was no statistically significant difference between the different groups, Dr. Geller said.
There was a tendency to use more power with more severe floaters. Between phakic and pseudophakic eyes, there was no statistical difference in the treatment results. There was also no statistically significant different outcome among eyes with various comorbidities, such as those with glaucoma, cataract or macular degeneration.
There was, however, some indication that there was a lesser rate of improvement [in these eyes], he said.
Theoretically, the more severe the floater, the poorer the treatment results.
There was no improvement in 17 cases, and they were in the most severe pretreatment group, he said.
Complications included five cases of transient high IOP that were controlled with medication and returned to normal.
Several eyes had mild pain that was treated with topical steroids.
For Your Information:
- Scott L. Geller, MD, can be reached at the South Florida Eye Clinic, 29 Barkley Circle, Fort Myers, FL 33907; (941) 275-8222; fax: (941) 275-9080; e-mail: firstname.lastname@example.org.