What is ptosis? What are its symptoms?
“Ptosis” refers to a drooping eyelid, and means that an upper eyelid falls to a position that is lower than normal. Because the involved eyelid may sag to the extent that it covers the pupil of the eye, it may interfere with normal vision by obscuring the upper aspect of the field of vision. In addition to the visual consequences, some patients find that a drooping eyelid has an undesirable effect on their appearance, and elect to have their eyelids raised to address the cosmetic issues associated with this problem. Ptosis may affect one or both eyes.
What are the types of ptosis? How are these causes treated?
In cases of levator dehiscence ptosis, the tendon of the muscle that lifts the eyelid (the levator palpebrae) may loosen or detach from its point of insertion. As a result, the muscle’s natural effect is weakened. The risk of this type of ptosis increases with age, although cases of trauma, prior eye surgery, and contact lens use may result in levator dehiscence. When this problem occurs, surgery can be performed to re-attach this tendon or to shorten this muscle to increase its strength. This surgery is generally performed under local anesthetic, except in children, and carries an excellent success rate.
Congenital ptosis is usually due to a developmental problem with the levator muscle. This problem is generally present from birth, although it may be diagnosed slightly later in life. Congenital ptosis may also be treated by shortening the levator muscle, although certain patients require suspension of the eyelid from the eyebrow.
Weaknesses of the muscles of the eyelid or malfunction of the nerves that control these muscles may result in ptosis. A careful examination by an ophthalmologist is critical to assess these situations and to look for specific underlying causes. Consequently, these patients generally require medical treatment and may not need surgery.
Other cases of ptosis are due to masses that increase the weight of the eyelid, such as a cyst, tumor, or swelling. In these cases, the muscles of the eyelid function normally, but they are required to lift a heavier weight and the eyelid subsequently droops. These cases are best dealt with on a case-by-case basis, as the treatment for these disorders varies considerably.
While excess skin around the eyelids (dermatochalasis) and drooping of the eyebrows (brow ptosis) are not truly causes of ptosis, they may create situations by which it appears that the patient’s eyelids are lower than normal. Excess skin can generally be addressed by removal (blepharoplasty). Eyebrows can be elevated surgically (brow lift).
Regardless of the age of the patient or the degree of ptosis, each patient requires a careful examination. With proper evaluation and intervention, the prognosis is excellent for this problem.