What changes with ptosis surgery? How eyelid-lifting works and what surgery alone cannot fix

Ptosis surgery works by tightening or advancing the muscle that lifts the eyelid and the membrane at its end (levator aponeurosis), restoring a drooping eyelid to its normal height[1][2]. Beyond appearance, studies report that the procedure widens the visual field and improves quality of life[3][4]. On the other hand, asymmetry between the eyes or height discrepancies may remain, and depending on the cause, surgery alone may not resolve the issue[3][5].

Why does the eyelid droop?

Adult ptosis is most commonly caused by thinning of the membrane that lifts the eyelid or by separation of that membrane from its attachment point[1]Contact lens use has been identified as a risk factor, and it can also occur after cataract or glaucoma surgery.[3].

Other causes include congenital conditions, neurological or muscular disorders, and injury.[4]Normally, the eyelid margin sits approximately 2–3 mm below the upper edge of the pupil; when it drops further, it affects vision and appearance.[6].

What is done during surgery?

The four basic surgical approaches are: suspension using the forehead muscle, shortening the levator muscle that raises the eyelid, repositioning the fascia, and resecting the Müller muscle (muscle on the inner eyelid).[2]If the levator muscle retains 5 mm or more of function, the technique of advancing the muscle or fascia forward is used regardless of the cause.[7].

In cases of congenital severe weakness of the levator muscle, the forehead suspension technique is chosen.[8]The skin-incision approach removes excess skin at the same time, while the non-incision approach is suited for those who want to minimize downtime (the period until swelling subsides).[5].

What is the difference between the skin approach and the internal approach?

For mild to moderate sagging, the improvement in visual field is nearly the same with either approach. According to U.S. guidelines, the improvement in eyelid height from the skin side averaged 1.8 mm and from the internal side averaged 1.7 mm, with no difference.[1].

For severe sagging, the skin-side approach is reported to yield greater improvement in visual field over the long term.[1]On the other hand, there are reports that the internal approach resulted in less eyelid contour distortion and fewer revision surgeries, though the data remain limited.[1].

How much does the eyelid rise after surgery?

In one study, 50 patients who underwent surgery from the internal side showed the distance from the center of the pupil to the eyelid margin expanding on average from 1.65 mm to 3.2 mm.[4]On average, even after about 2 years, patients continued to report improved quality of life.[4].

What are the risks?

The main risks are asymmetry, overcorrection or undercorrection, bleeding, difficulty closing the eye, and infection.[3]Dry eye or distortion of the eyelid curve contour can also occur.[9].

Surgery from the skin side depends more heavily on physician experience, and careful attention must be paid to asymmetry, recurrence, and shape changes.[6]When drooping persists even after swelling subsides and the wound heals, it is possible that the muscle or fascia was stretched or detached during surgery.[10].

What if surgery alone does not resolve the problem?

If the cause is myasthenia gravis (a disease that causes muscle fatigue), medication treatment should come first. In one study, only patients who did not improve after more than 2 years of medication treatment were considered surgical candidates.[5].

In children with congenital sagging of one eye, even if the eyelid rises after surgery, amblyopia (a condition in which vision does not develop fully) may persist.[11]People planning cataract or vision correction surgery are advised to consider eyelid surgery first, as the corneal shape will change.[1].

How does the physician decide which method is right for you during examination?

Eyelid surgery method varies depending on the cause of sagging and the strength of the muscle that raises the eyelid. During a physician's examination, make sure to have the degree of sagging, muscle strength, skin laxity, asymmetry, and dry eye evaluated.[7][1].

If you have underlying conditions or planned eye surgery, discuss these as well, as this will make it easier to determine the order and method of surgery.