Macular Pucker
The macula is the central part of the retina, directly in the back of the eye. Light from images are focused on the area, and because of its unique structure, a sharp image is relayed to the brain. Any damage to the macula will result in decreased vision, and one of these conditions is a macular pucker.
A macular pucker occurs when scar tissue forms over the macular distorting the surface and therefore, creating symptoms of distorted and/or a blurred image, difficulty is doing close work, cloudiness, or even a blind spot. It is similar to projecting an image onto a movie screen which is not perfectly flat.
How Does a Macular Pucker Occur?
Scar tissue can grow over the macular due to any inflammatory condition resulting from an infection, trauma, eye surgery, and a vascular occlusion, however, the most common cause is aging. In any event scar tissue cells proliferate on the surface of the macular, and once mature they contract. This contraction pulls on the retina creating wrinkles on the surface of the macula, and in more severe cases can cause the small vessels in the retina to leak, resulting in the accumulation of fluid within the macula (cystoid macula edema). This swelling can cause even greater loss of vision. Often the decrease in vision is not severe enough to warrant any treatment, but when it does, surgical intervention is necessary.
The diagnosis of a macular pucker is made on the clinical exam, and with a special study called an OCT (ocular coherent tomography) and/or a FA (fluorescein angiography), details of the severity and extent of the macular pucker can be gathered. This information is important to know pre-operatively so the treatment can be planned accordingly and any difficulties anticipated.
When Do You Know Surgery Is Necessary?
The decision to perform surgery on a macular pucker is made once there is documentation of a significant loss of vision, usually below the level of 20/50, and the patient is symptomatic, i.e., complaining that the decrease in vision is affecting their normal life style. Additional considerations are the progression of the patient’s loss of vision and the presence or absences of edema. These factors would influence the decision as to how quickly the surgery should be done, otherwise the surgery could be scheduled at the patient’s convenience.
What Is The Surgical Success?
Surgical success is very high in the 95% plus range. The visual success rate varies according to the preoperative vision and the presence of cystoid macular edema, the length of time the pucker has been present, and the severity of the pucker itself. Generally, it is considered a visual success if there is a 50% improvement in vision, but often a much better percent improvement is achieved.
What Are The Surgical Risks?
As in any major intraocular eye surgery, there is the risk of a complication. The possible complications include a hemorrhage, infection, retinal detachment, scar tissue formation, and increased intraocular pressure. They constitute a less than 5% risk and can be well managed when addressed promptly. In patients who have not had cataract extraction the risk of acceleration of the cataract can be as high as 70%, therefore,in the more elderly patients who already have moderate cataracts, the cataract is removed prior to removing the macular pucker.
How Is a Macular Pucker Managed?
Normally if there is only a mild loss of vision, and there is also some cystoid macular edema, topical eye meds may be used to see if a better level of vision can be obtained with resolution of the edema, without surgery. If this does not improve vision, surgery is considered.
Surgery for a macular pucker involves a vitrectomy (removing the vitreous) from within the eye. The vitreous is removed through the use of several small instruments, introduced into the eye through the white part of the eye, a few millimeters away from the colored part. Without removing the vitreous, the surface of the retina cannot be safely approached. Once the vitrectomy is performed, the membrane on the surface of the macula can be addressed. Since the membrane is transparent it is often necessary to first stain it with a dye, then engage the membrane with a small instrument to create an edge. The edge of the membrane is then elevated and grasped with forceps and dissected off the surface of the macula. Occasionally, the membrane is so well organized, that staining is unnecessary and the membrane can be dissected off the macula by injecting a viscous fluid under it. This can simplify the dissection, which can elevate the entire membrane at once. Normally the membrane comes off in sections, requiring multiple approaches at the retinal surface, increasing the risk of retinal/macula trauma.
What Is The Recuperative Period?
Surgical recovery is relatively rapid, lasting approximately 3-6 weeks. Visual recovery may also be rapid,but may also take up to 6 months. As a rule-of-thumb, the best corrected vision at 6 months is the final and optimal vision. During the recovery period, activity is somewhat limited to no running, jumping, stooping or lifting anything over 10 pounds. Topical eye meds are administered for 3 to 4 weeks post surgery, and are tapered off by the fourth week. Return to work depends upon the type of work the patient performs. Those who do a significant amount of strenuous work, will have a longer recuperative course then those who do not, but it rarely extends longer than 6 weeks, assuming there are no complications, even though the full recovery period for follow-up is 3 months.