Treatment for Retinopathy of Prematurity
Treatment for ROP depends on the stage and degree of retinal findings. Generally, Stages I and II resolve on their own and only require periodic evaluation.
Treatment is initiated when threshold ROP, stage III with certain qualifying signs, is seen. This means that the condition of the eye has degenerated to a point beyond spontaneous resolution and where vision is seriously threatened. The goal of treatment is to help reduce the risk of retinal detachment and dragging of the macula, which can severely impact vision.
Laser photocoagulation is the most common treatment modality. A laser is directed to a designated spot to destroy abnormal vessels and seal leaks.
The procedure usually is performed under general anesthesia because these infants are typically extremely premature and have multiple medical problems. Laser photocoagulation is the preferred method of treatment by surgeons, because there is little postoperative pain and swelling.
Cryotherapy can be used to treat threshold ROP but is not the preferred method. Cryotherapy involves destroying abnormal tissue by freezing and is often used to treat Grade III ROP. A probe chilled with nitrous oxide is placed on the surface of the eye. Because the tissue of the sclera is thin, the freezing temperature is easily transmitted to the retina.
Cryotherapy reduces the risk for retinal detachment from 43 to 21 percent. It is an effective therapy for preserving vision in many infants with ROP, but it does have drawbacks. Narcotic analgesia may be required after the procedure to relieve pain. Cryotherapy also causes significant swelling of the eye and eyelid, which makes postoperative assessment difficult.
Scleral buckle may be used in Stages VI and V ROP to prevent retinal detachment. This procedure is used when laser or cryotherapy fails to prevent disease progression. A band made from silicone or other flexible material is placed around the back of the eyeball to "buckle" (indent) the sclera. This brings the eye wall closer to the retina, helps to reattach it, and relieves the traction that was pulling on it to cause detachment. Infants often have the band cut at a later date to accommodate the growing eye.
Vitrectomy is performed on Stage V patients, when scleral buckling is no longer effective. This is a complex procedure, which involves the use of microscopic instruments to remove the vitreous from the eye and replace it with a saline (salt) solution. When the vitreous is removed, traction on the retina is relieved.
Scar tissue on the retina is cut or peeled away once the vitreous is removed, allowing the retina to reattach. Unfortunately, the lens frequently has to be removed as well to allow all scar tissue to be removed. Vitrectomy techniques that preserve the lens are becoming more common.
Retinopathy of Prematurity Prognosis
Success rates for reattachment of the retina range from 25 to 50 percent. However, reattachment does not guarantee that the infant will have functional vision. Only about one-quarter of infants whose retinas reattach are able to see well enough to recognize patterns or to grab for a toy.
Premature infants with ROP have a high risk for strabismus and amblyopia. Infants with regressed ROP are at risk for eye problems as they grow. These are called late complications of ROP.
In addition to strabismus and amblyopia, they are also at risk for myopia, glaucoma, and retinal detachment. ROP complicated by retinal detachment is the leading cause of blindness in children in the United States. Approximately 500 cases of ROP-related blindness are reported every year.
Infants with Stages IV and V ROP may have severe amblyopia, which makes therapy and visual rehabilitation difficult. Those with Stage V also have a 30 percent risk for developing angle closure glaucoma.
Retinopathy of Prematurity Prevention
The best way to prevent ROP is to avoid premature birth. Prenatal care and counseling can help prevent premature births and inform a mother about factors that influence her baby's health in utero.
Other preventative interventions include closely monitoring oxygen needs in premature babies. Regular eye exams should be discussed with the baby's physician, regardless of the stage of ROP.