Retinal Tears and Detachment
A vitreous detachment occurs suddenly without any warning. It is more common as people get older. By age 60, 90% of all people will have a vitreous detachment in at least one eye. It is so common we consider it to be a normal part of getting older. Patients that are very nearsighted have a higher chance of a vitreous detachment at a younger age, as do people who are hit in the eye or in the head.
In some patients, the collapse of the vitreous occurs in stages rather than all at once. For that reason, Dr. Kirsch or Dr. Hairston will examine the patient when the symptoms first occur and then again 6 to 8 weeks later. If the floaters and flashes suddenly get worse at any time or if a grayish curtain appears in your peripheral vision, you should call the office immediately. This advice holds true if these symptoms occur in your other eye. Often, the vitreous in both eyes will detach within a year of each other.
In the vast majority of patients, a vitreous detachment is annoying but not dangerous. However, in some people the vitreous gel tugs so much on the retina it causes a tear or hole to form in the retina. In many of these patients, the saltwater that is now free inside the eye can go through the hole and cause a retinal detachment. Therefore, it is imperative that all patients who experience flashes and floaters have a detailed examination of the vitreous and retina by a retina specialist who is an expert in this area. If a hole or tear is found in the retina, it can be easily treated using a laser. The laser seals the tear by making “spot welds” in the retina and prevents fluid from going under the retina and creating a retinal detachment. If a retinal detachment has already occurred, an operation performed by a retina specialist is usually required. Patients, who are at a higher risk of getting a retinal detachment, include people who are very nearsighted, those who have had a retinal hole or detachment in the other eye, or who have a family history of retinal detachment.
The main symptom of a retinal detachment is the sensation of a “curtain” coming across the field of vision from the side toward the center. The curtain gets progressively larger over several hours or days. As the detachment reaches the center of the retina (the macula), the vision becomes very blurry, often preventing the patient from seeing anything other than fingers in front of their faces. The curtain can come from any direction (left, right, top or bottom) and is related to which part of the retina detaches first. There is often a sensation of waviness, as the retina undulates because of the fluid underneath it. The flashing lights and floaters will persist during this time. A retinal detachment is a true emergency and needs to be treated as soon as possible; ideally, before it reaches the macula. Once the macula detaches and depending upon how long it is detached, the likelihood of regaining normal vision in the eye is significantly diminished.
Treatment of Retinal Tear and Detachment
Treatment of a retinal detachment depends upon several factors. There are three main procedures used to treat retinal detachments. A pneumatic retinopexy is a procedure performed in the office in which the retinal tear causing the detachment is treated with cryotherapy (a freezing probe). A gas bubble, usually perfluoropropane, is injected into the eye under sterile conditions. You will be given drops and perhaps some oral medications to take after the procedure. The most important part of a pneumatic retinopexy is the positioning the patient must maintain after the procedure. The position you will be asked to maintain depends on the location of the tear causing the detachment. For example, if you have a tear on the right side of the retina in the right eye, you will be asked to lie on your left side. The reason for this is so that the gas bubble can float to the side of the tear and seal it off, allowing the fluid under the retina to be reabsorbed over 2 to 4 days. You would then have an appointment to see the doctor and, if the retina is reattached, he will perform laser treatment to tack the retina down in the area in which it was detached. The gas bubble will reabsorb in 4 to 6 weeks. Only certain retinal detachments are eligible for a pneumatic retinopexy, usually depending on the location of the tear in the retina and the patient’s ability and willingness to maintain the positioning after the procedure. Pneumatic retinopexy has a 95% success rate.
If there is more than one tear in the retina, the tear is located at the bottom of the retina, there is too much blood in the vitreous cavity, or a significant amount of scar tissue has formed on the retina, then a pneumatic retinopexy is not a viable treatment option. In those patients, a vitrectomy is performed in the operating room. In a vitrectomy, the vitreous gel and any blood or scar tissue are removed and the retina is reattached during the procedure by aspirating the fluid from underneath the retina while simultaneously infusing air into the eye. Freezing treatment and/or laser treatment is performed to seal the tears in the retina. The air is then replaced with gas or silicone oil. The gas will reabsorb and disappear in 4 to 6 weeks. The silicone oil will be left inside the eye for 4 to 6 months, and then will be removed if the situation permits. Silicone oil is usually reserved for eyes with more severe detachments or eyes in which the retina has detached more than once or twice. Whether gas or silicone oil is used, the surgeon may ask you to lie in a certain position for several days after the surgery. Vitrectomy surgery for a primary (first) detachment has a 95% success rate, though recovery of vision may not occur for 6 to 12 months.
Scleral buckling is a procedure performed in the operating room in which a plastic band is placed around the outside of the eye, under the four rectus muscles. It is sewn to the wall of the eye and tightened to indent (buckle) the wall of the eye. You can think of it like a belt that goes around your waist to hold up your pants. The buckle remains in place permanently. The operation requires an incision all around the skin of the eye and can result in a moderate amount of pain postoperatively. A scleral buckle may be performed as a procedure all by itself or it may be combined with a vitrectomy. Your eye surgeon will discuss these options with you and recommend the one he feels gives you the best chance of reattaching the retina.
The main reason for the failure of retinal detachment surgery is the formation of scar tissue, usually about 6 weeks after the procedure. This complication is called proliferative vitreoretinopathy and occurs in 3 to 5% of all eyes. There is no known way to prevent this problem. If enough scar tissue forms, it can pull the retina off the wall of the eye or cause additional holes to form in the retina. Eyes with proliferative vitreoretinopathy usually require more advanced surgery to correct the problem, usually involving a scleral buckle and silicone oil.
In summary, flashes and floaters are very common problems. Although a vitreous detachment is usually not dangerous by itself, it can have serious consequences. Therefore, call Dr. Kirsch or Dr. Hairston immediately if you experience these symptoms. Your eyesight may depend on it.