How strabismus surgery works

The goal of strabismus surgery is aligning the eyes, improving aesthetics and, in some cases, improving patient comfort by eliminating double sight.

In strabismus surgery, the surgeon weakens or strengthens ocular muscles, causing changes to the position of the eyes.


Access to ocular muscles:

The muscles are inserted in the sclera (white of the eyes) and are covered by a fine layer of transparent tissue, the conjunctiva. The palpebra are kept open by a small instrument called blepharostat. The surgeon makes a cut, or incision, in the conjunctiva to reach the ocular muscles and uses a delicate hook to isolate the muscle to be operated. There are no incisions on the skin. There is no need to remove the eye during the procedure.

Muscle recession or retreat

A recession or retreat is the procedure to weaken the ocular muscle. After being removed from the sclera, the muscle is moved further back, changing the location where it normally inserts into the eyeball. The surgeon uses stitches, or sutures, to attach the muscle to the sclera and those stitches do not need to be removed after the surgery.


Muscle resection
Resection is the procedure to strengthen the ocular muscle, by removing a small portion of it and reinserting it on the same spot with a suture. Thus, the muscle becomes shorter and therefore stronger.



After the procedure, the membrane that covers the ocular muscles is sutured, leaving no scar.

The type of anesthesia depends on patients age and health status, as well as preference. Children are operated under general anesthesia, as they must remain motionless during the procedure. Adult surgery may be performed under general anesthesia or under sedation and local anesthesia, depending on surgeon preference. It is generally an ambulatorial surgery, which means patients are admitted and released on the same day.



It is generally quick and patients can soon resume their activities. In the period immediately following the surgery, eyes become red at the incision location and a sandy feeling occurs. It lasts for a few days, until the stitches are absorbed. It is not necessary to remove the stitches. The redness improves gradually and, in general, the eyes become white again one month after surgery. Patients must avoid extenuating activities and swimming in seawater or pools for 3 weeks.


What are the risks related to strabismus surgery?

Every surgical procedure involves risk, both related to the procedure itself and to the anesthesia. But, in general, the risks of complications in strabismus surgery are minimal, with the most common being the need for a new surgery to correct any remaining deviation. We know that one in five patients need more than one surgery to align the eyes.