The upper eyelid needs to open sufficiently wide in order to clear the visual axis (i.e. clearing the pupil). Weakness of the muscle opening the eyelid (levator palpebrae superioris, or “levator”) can cause a droopy eyelid (“ptosis”) that covers the pupil. This can affect both eyes (“bilateral”) or just one eye (“unilateral”). When the child needs to raise their chin in order to see from under the eyelid, that is called “ocular torticollis,” which can harm the neck and back muscles and interfere with gross motor development. When the child has unilateral ptosis, the covered eye may be ignored by the brain, resulting in neurologic vision loss, or “amblyopia.”
Correcting ptosis can be done at any age, but the only reason to perform surgery in a very young child is to avoid vision loss or developmental delay. Otherwise, the surgery can wait until the child is at school age.
Surgery to correct ptosis may involve tightening the weak levator muscle, removing congenitally thickened connective tissue from around the muscle, or bypassing the muscle and connecting the eyelid directly to the forehead muscle (“frontalis”) so that the eyelid opens when the brow is elevated. Each of these procedures can be performed via a variety of techniques. Dr. Kahana has experience with all modern techniques.
Whenever possible, he prefers to remove abnormal connective tissue and tighten the levator muscle in order to give it a chance to regain function. Approximately 50% of patients who are predicted to have minimal levator function end up having reasonable function following surgery.
Sometimes, when the levator muscle is particularly weak, Dr. Kahana will also perform a frontalis muscle reanimation technique, in which a vascular flap of frontalis muscle is recruited into the eyelid so that the eyelid moves with brow movement. Some people refer to the technique as “frontalis sling,” although Dr. Kahana usually avoids the use of a formal sling material, preferring the more biological approach of frontalis muscle reanimation. There are many advantages to the reanimation technique, including avoidance of an implant and associated complications, and the reduced need for “redo” surgeries when the implant fails. However, there are situations in which Dr. Kahana will use a traditional frontalis sling, such as when the health of the patient necessitates minimal surgical time.