Everyone has vitreous floaters, to some degree. For most people, floaters are a minor annoyance, occasionally noticeable when looking at a light-colored background, as in a white wall, freshly fallen snow, or the sky. These floaters move as the eye moves and if you try to look at them directly, they move away just as you attempt to fixate on them, always visible but just out of reach.
For some individuals, floaters can be a major nuisance, popping into the central visual field at inopportune times, as in when reading or driving. When driving or during another potentially dangerous activity, such a distraction or visual obscuration at the wrong moment can lead to an accident, or worse.
I will review the issues I think about when evaluating a patient considering vitrectomy surgery for floaters, and address the pertinent issues to discuss with patients to assist them in making an informed decision for or against surgery.
Specifically, these discussion points include how to decide upon the need for surgery, realistic expectations, potential side effects and complications of surgery, and other patient or eye-specific issues.
Pathophysiology of vitreous floaters
Vitreous floaters are typically due to aging of the vitreous gel, a process called syneresis. At birth, the vitreous has a consistency of freshly made and refrigerated gelatin, solid, homogenous, and clear. Vitreous degeneration begins soon after birth, accelerating throughout life. During teenage years, the vitreous gel slowly starts to separate from the midperipheral retina. Many at that age will notice an occasional floater in their vision but only as an interesting phenomenon, not something disabling. In middle age, there is enough vitreous degeneration that floaters may become bothersome.
Myopic patients may have more prominent floaters as a group due to vitreous degeneration and liquification and earlier posterior vitreous detachment (PVD).
It is important to consider other causes of floaters including uveitis and vitreous hemorrhage, which may benefit from nonsurgical treatment. Asteroid hyalosis is thought to be asymptomatic but if sufficiently dense can impair vision just as with prominent floaters, and likewise benefit from surgical removal.
How to decide on surgery
Most new patients I see for a floater vitrectomy, or floaterectomy for short, have already seen at least one other eye care professional who referred them to me. This means that the patient was sufficiently bothered by their floaters to raise the issue with their optometrist or ophthalmologist, and after a conversation, was referred to me as a retinal specialist for surgical consideration. This process alone selects out those with minimal symptoms or else not interested in surgery.
I ask how long the floaters have been present. A recent PVD may cause a shower of floaters but in most eyes, these will settle over time and the patient may adapt to the remaining floaters or Weiss ring. For this reason, I advise patients to wait at least 3 to 4 months before making a decision regarding surgery. If the floaters are improving during this time, I prefer to observe rather than operate, as eventually the symptoms may resolve or at least become tolerable.
Since these patients are referred, by the time they see me, they have been bothered by their floaters for at least 3 to 4 months, perhaps much longer, so additional waiting is no longer necessary.
If the floater is discrete, as in a Weiss ring, laser vitreolysis can be attempted if one has access to an appropriate laser. Shah and Heier performed a prospective, randomized clinical trial comparing YAG laser vitreolysis to sham treatment. The YAG laser group reported greater symptomatic improvement with laser compared to sham at 6 months (54% versus 9%). Functional measures of vision quality also improved in a statistically significant way and adverse events were minimal.
Real-life experience with YAG vitreolysis suggests that multiple treatments may be needed and that adverse events are possible, including damage to the retina or to the lens, whether crystalline or artificial.
Laser is only effective for discrete floaters, as in a Weiss ring, not more generalized vitreous syneresis. These patients complain of a cloud moving in and out of their visual field, resembling a lava lamp effect. These eyes can only be helped by surgically removing the vitreous.
Other ocular conditions are relevant. If a patient is phakic, vitrectomy surgery will accelerate normal age-related cataract development. If they have lattice degeneration or a history of retinal tears, vitrectomy surgery increases their risk of a retinal tear or detachment, both intraoperatively and postoperatively.
Surgery eliminates most but not all floaters, getting rid of the large bothersome ones. There can always be an occasional small floater noticed periodically after successful surgery. A single blood cell in the vitreous cavity will be noticed in certain lighting conditions or against light backgrounds. It is like cleaning your windshield. No matter how well you clean it, if the light hits it a certain way you may notice a streak or smudge, even though for the most part it is crystal clear.
Vitrectomy is performed as outpatient surgery, either in an ambulatory surgery center or hospital, depending on surgeon preference and logistic factors. Anesthesia is either local with sedation or general, again depending on the surgeon’s and patient’s choice. It typically takes about 30 minutes and is covered under major medical insurance.
Postoperative care is similar to other uncomplicated vitrectomy surgery including antibiotic/steroid eye drops for a week or two and return to work and normal activity within a week. Postoperative positioning is not required.
If floaters are present in both eyes, I operate on the worse eye first. That may be enough if the fellow eye floaters are minimal. On the other hand, after removing floaters from one eye, patients frequently notice the dramatic difference between the two eyes and can’t wait to have the fellow eye done. I like to wait about a month between eyes to get beyond the most likely time of surgical complications which may influence the decision regarding the second eye.
It is important to explain that cataract progression is expected, in other words, a side effect, not a complication.
I use an air bubble routinely after small gauge vitrectomy to seal the sclerotomies to prevent post-operative hypotony or endophthalmitis, although the eye can be left fluid-filled when necessary. Air in the eye precludes flying or mountain travel for a week. Omitting the air bubble allows these activities shortly after surgery.
Side effects and complications
All eye surgeries have potential risks, with the major ones being hemorrhage, infection, and retinal detachment. Fortunately, these complications are rare.
Cataract progression, as mentioned above, is an expected side effect, not a complication.
If the eye undergoing floaterectomy is already pseudophakic, I remove the posterior lens capsule at the time of surgery. Nothing is more disconcerting than 6 months after a beautiful result from vitrectomy for floaters, the patient undergoing a YAG capsulotomy with new floaters due to bits of lens capsule floating in the vitreous cavity.
If there is a visually significant cataract and floaters, I recommend removing the cataract first as it is easier for the cataract surgeon to operate on a non-vitrectomized eye. Sometimes the vision improvement after cataract surgery is enough for the patient to no longer need floater surgery. Other times, the vision improves enough that the patient notices and is even more bothered by the floaters and is more eager for surgery.
If the eye has lattice or previous retinal tears, I perform prophylactic peripheral laser to any pathology to reduce the chance of post vitrectomy RD. It’s disconcerting to achieve an excellent result after floaterectomy only to then have to operate again to repair a retinal detachment. It’s the old “ounce of prevention versus a pound of cure” analogy.
I occasionally see younger patients with symptomatic floaters, often myopes, but no posterior vitreous detachment yet, confirmed by OCT testing. For these I perform only a central vitrectomy to remove the floaters, leaving the posterior hyaloid in place. Detaching a firmly attached hyaloid can be difficult in a younger patient and increases the risk of retinal tear or detachment, during or after surgery. I warn the patients that in the future when they naturally develop a PVD, they may have new floaters, perhaps bothersome, perhaps not. But to me, the safest course for these patients is to do only what is necessary and not add risk to the surgical procedure.
These are among my happiest patients. Often when I repair a retinal detachment, the patient is more thankful that I eliminated their floaters than fixing their detachment and restoring their vision.
Despite operating on relatively normal and healthy eyes, similar to what we do in refractive surgery, if we can relatively safely improve our patients’ quality of vision and set realistic expectations, it’s a winner for everyone.