Eyelid Ptosis

Drooping of the upper eyelid (eyelid ptosis) is a very common reason for consultation. It can occur at any age throughout life. In general, the consultation is usually for cosmetic reasons, but on some occasions, it can cause loss of vision due to partial or total obstruction of the field of vision. It can also cause tiredness or pain in the forehead, due to the attempt to compensate for the drooping of the eyelids by raising the eyebrows.

The first thing to rule out is that the eyelid is not really drooping, and that what the patient notices is the excess skin that occurs with ageing, which is corrected with a blepharoplasty. On other occasions, what happens is a drooping of the eyebrow, which also produces an asymmetry in the gaze, which the patient usually notices as if “the eyelid is drooping”.

CAUSES

The causes of eyelid drooping are multiple. In adults, the most common causes is due to the detachment of the muscle that lifts the eyelid (levator palpebrae superioris muscle) from its normal insertion point (tendon desinsertion). In children, the most common cause is that the muscle responsible for lifting the eyelid does not form properly during pregnancy (embryonic development) and lacks its normal strength. The degree of strength loss varies, from absent to nearly normal. In adults, other possible causes include muscle diseases that result in weakness in the levator palpebrae superioris muscle (muscular dystrophies) or nerve abnormalities affecting the signals that instruct this muscle to open the eyes. Clinical evaluation before surgery is crucial, as although surgery is the treatment for almost all ptosis cases it may vary depending on the degree of residual levator muscle strenght, and less commonly, some causes of ptosis may require specific alternative treatments.

All eyelid ptosis can be improved with surgery, and in most cases, symmetry between the two eyes can be achieved. The surgery will depend on the cause of the ptosis.

APONEUROTIC PTOSIS

In aponeurotic ptosis (because the muscle has come loose from its place) the muscle is put back in place (reinsertion of the upper eyelid levator aponeurosis).

MYOGENIC PTOSIS

In myogenic ptosis cases (due to muscle dysfunction), both in children and adults, the approach involves shortening and tightening the muscle to make it stronger (levator palpebrae superioris muscle resection). In cases where the muscle is completely non-functional, another muscle must be used to open the eye, and the only alternative is the muscle that raises the eyebrows (frontalis muscle, located above the eyebrows). This muscle can assist in opening the eyes under normal conditions but does so with very weak force. With surgery (frontalis suspension), the goal is to strengthen this mechanism significantly so that it becomes effective on its own in opening the eyes. This is typically achieved by connecting the eyelid to the frontalis muscle using strips of fascia harvested from the patient’s own leg (autologous fascia lata graft, which is very resilient, flexible, and does not face rejection as it comes from the patient themselves). Other possible option is to use a frontalis flap to create a stronger union between the lid and the frontalis muscle.

All eyelid ptosis surgeries are generally performed under local anaesthesia and intravenous sedation in order to be calmer and more comfortable during surgery, except in children, where general anaesthesia must be used because they do not cooperate. Local anaesthesia allows for intraoperative (during surgery) adjustment of the eyelid height. The success rate of the surgery is very high, although in a small percentage of cases (between 5-10%) some touch-up may be necessary, either because the height, shape or symmetry are not as desired.

ARE MY EYES GOING TO LOOK WIDER?

Hypercorrections are very rare in eyelid ptosis surgery. In the most frequent ptosis, due to disinsertion of the muscle, they are exceptional, so that, although there may be a slight difficulty during the first few days in closing the eyes, this does not cause any problems. In ptosis in which the muscle does not work well, there is a small risk of hypercorrection (eyelids more open) and greater difficulty in closing. Preoperative assessment of the entire ocular surface and close postoperative follow-up are therefore very important. Following these guidelines, both aesthetic and ocular complications are exceptional.