Risks of Laser Treatment
There are two decades of experience with the laser vitreolysis procedure. It has proven itself to be a low risk procedure and an attractive alternative to 1.) Doing nothing, or 2) Surgical Vitrectomy. As with anything medical and interventional, the laser procedure is not without risk, but the likelihood of vision threatening complications is very, very low.
The only way to have no risk is to do nothing. We believe that for most patients, the potential benefits WELL outweigh the potential risks of the laser procedure – IF the floaters affect the quality of vision and the quality of life.
Here is a listing and explanation of the major real and theoretical risks and challenges of using the laser for eye floaters:
Not so much a risk, but still an important consideration. The optics of the treating laser are designed more for use toward the front of the eye and in the central visual axis rather than the periphery of the eye. The further back the floaters are, the treatment increases in difficulty and inefficiency (delivering less energy than desired). The laser energy can be blocked by small pupils, small lens implants, and made more difficult in very nearsighted eyes. Floaters in the periphery of the eye are very difficult to treat and even though we may see them quite clearly, the laser energy may be so diminished that very little happens when the laser is activated. Some of this challenge can be compensated for by a skilled and experienced laser specialist, but not always.
INABILITY TO TREAT SOME FLOATERS
The treatment of eye floaters is highly individualized and dynamic. It impossible to predict exactly how the floaters will behave. That unpredictability is more so in younger patients. There exists the distinct possibility that despite our best, most dedicated and meticulous effort, there may be some residual material that simply cannot be safely treated, or remains inaccessible.
Some floater material may be located too close to the lens or retina to safely treat. They may be so microscopically small, that we may not even be able to located them on examination. This is more typical for the younger patients.
RECURRENCE OF FLOATERS
Ideally, the floater material that is directly hit by the laser should be permanently vaporized. Unfortunately, the laser is not entirely efficient, especially for the larger, cloudier (syneresis) type floaters. These have a tendency to reform somewhat, sometimes as soon as the next day.
These “reformed” floaters are usually quite treatable with subsequent, follow up laser treatments. Because of this tendency, it is rare to be able to treat someone in just one treatment session. Most people will need a second and 3rd (and sometimes more) treatments to achieve a satisfactory outcome.
The re-formation, re-aggregation, and clumping of remaining collagen protein fragments may occur despite an adequate and aggressive first treatment. The aggregated floater most often appears as a ‘fuzzy’ linear strand. Although there is much less material involved, these floaters can still be quite bothersome.
This may continue with the ‘3-4 steps forward and 1-2 steps back. Continued re-formation of smaller fuzzy linear strand may continue until there is less material, or the remaining material is not bothersome, or no more material reforms. There is no way to predict how many treatments it takes to get to these ‘endpoints’ as it varies from eye to eye.
This is quite rare and mostly avoidable by recognizing the risk factors in advance and either not treating at all, or limiting the amount of treatment. We estimate the incidence to be 3-5 episodes per 1000 treatments based on cumulative reported and anecdotal conversations with other providers. There does not appear to be a direct correlation between the amount of treatment (number of shots or total energy used) and the elevation in pressure for the typical patient. There may be some predictive risk factors such as the following:
pre-existing elevated eye pressures (suggests poor fluid drainage)
previous cataract surgery (changes the anatomy of the front of the eye)
large, dense floaters in the front one-third of the eye (there must be enough mass of material available and located closer to the natural drainage pathways)
aggressive treatment (release more microscopic protein debris)
Significant elevations of eye pressure may require treatment with eye drops or oral medications until the pressure problems resolves, usually weeks or a few months later.
A cataract is a change in the clarity of the crystalline lens in the eye. There always exists the potential for the creation of a (traumatic) cataract by the laser, but it would essentially take a direct hit (or one of very close proximity) to the lens to do so. There are very few reports of cataract being caused by the laser procedure. If the laser breaks the outer lens capsule, the cataract that develops could be a rapid-onset traumatic cataract and may develop quickly as in days or weeks. A cataract may require surgical treatment. This risk is almost 100% avoidable by staying an adequate distance away from the lens when treating. We are aware of a few cases of cataracts being caused by the YAG laser. In each of these, it was the doctors first or early attempt in treating floaters or they were very new to the procedure. A good argument for seeing someone who is very experienced and qualified to treat eye floaters.
Some floaters located near the lens can sometimes be momentarily moved away from the lens where the laser can be safely fired. This is an advanced technique and not recommended for doctors new to the procedure.
This also should be a VERY avoidable risk with experience and good judgment. Good judgment may also include not treating particular floaters or not treating the patient at all. We have never had a patient lose visual acuity, lose peripheral vision, incur a retinal detachment, or other devastating injury to the retina since 2007 when we started treating floaters.
SUMMARY OF RISKS OF THE USE OF THE YAG LASER IN THE TREATMENT OF VITREOUS EYE FLOATERS
No medical intervention or activity is without risk. This is true of even very common procedures such as cataract surgery or LASIK. Even something simple like removing a simple skin tag or mole has the potential for adverse reactions to medications, infection, etc. When discussing risks is not enough just to state the risk, but it is also imperative to describe the relative risk, that is the question “What is the likelihood of that risk happening to me?”. Fortunately, in this practice with a combination of experience in the decision-making, we have had a very low incidence of risk to patients undergoing treatment. There’s been no loss of visual acuity or devastating complications.
Dr. Johnson could not and would not dedicate his entire professional career to this procedure if it had not shown itself to be acceptably low in risk and high in success for most of the patients undergoing treatment.
The in-person and personalized discussion of risks for any medical procedure is part of the informed consent process and occurs with Dr. Johnson prior to any treatment. We try to present a fair representation of the risks and potential risks of this procedure. Fortunately, virtually all risks listed above can be avoided by the experienced physician being aware of the focus of the laser at all times. Doctor Johnson is one of the most experienced ophthalmologists in this particular procedure with over 14 million laser bursts aimed at these sometimes elusive eye floaters. He has enjoyed a very high success rate because of the careful, conscientious, diligent, and unhurried approach to each treatment.
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