Some beauty seekers asked on the internet, I went to a certain institution for consultation to have my eyelids cut and they said: I have ptosis, and I went to a public hospital and the doctor said: I don’t have ptosis, so, am I ptosis or not? But in the future, beauty seekers won’t have this doubt anymore.
Not long ago, after a total of seven rounds of discussions and revisions organized by the Oculoplastic Specialty Committee of the Aesthetic and Plastic Physicians Branch of the Chinese Medical Association, the standards and criteria for the diagnosis and treatment of ptosis were finally developed.
Ptosis is a disease and must be treated!
Ptosis is a common clinical condition that not only affects the patient’s appearance, but can also have a negative impact on visual function. Since the first report of ptosis correction with simple skin excision, there have been dozens of surgical methods, including ptosis-related surgery, frontalis-related surgery, and Müller muscle-related surgery. Since the first reports of ptosis correction with simple skin excision, dozens of methods have been reported by scholars both nationally and internationally to correct ptosis.
With so many surgical options available, clinicians are often caught in a dilemma of choice and are not sure of the indications for surgery, resulting in unsatisfactory results and high complication rates. The Chinese cosmetic surgery market has developed rapidly in recent years, and many new treatments have emerged, but there are also many problems such as irregularities in treatment. To address these issues, this consensus was developed by the Oculoplastic Surgery Committee of the Aesthetic and Plastic Surgeons Branch of the Chinese Medical Association.
This consensus covers the diagnosis and classification of ptosis, the classification, preoperative evaluation, timing of surgery, intraoperative correction assessment, surgical style selection, postoperative care, and management of complications, in order to provide physicians with a basis for the diagnosis and treatment of ptosis from the most clinically relevant perspective and to guide them in the standardized treatment of ptosis for the benefit of patients.
Diagnosis and Classification of Ptosis
Under normal conditions, the upper eyelid margin covers the superior corneal edge ≤2 mm when the eyes are open and flat; if the frontalis muscle is excluded, the diagnosis of ptosis can be made by covering >2 mm.
In unilateral ptosis, the amount of ptosis can be estimated by comparing it to the normal side: the difference in height between the two sides of the lid fissure when the eyes are level is the amount of ptosis. In bilateral ptosis, the degree to which the upper lid margin obscures the cornea is observed and is classified according to the degree of coverage as.
(1) Mild: ≤4 mm of coverage, when the amount of ptosis is ≤2 mm;
(2) Moderate: masking >4 to ≤6 mm, with ptosis >2 to ≤4 mm;
(3) Severe: >6 mm of coverage, with coverage reaching the center of the pupil, when the amount of ptosis is >4 mm.
C. Classification of ptosis
According to the etiology, ptosis is divided into the following 5 categories.
1. Myogenic
Myogenic ptosis can be either congenital or acquired. In congenital cases, the ptosis is usually due to hypoplasia of the levator muscle, but it can also be due to disorders of the central and peripheral nerves that innervate the levator muscle; the pathology is characterized by the loss of the transverse striations of the levator muscle fibers, which are reduced in number and disorganized and replaced by fibrous and fatty tissue. Clinically, these patients show not only reduced contraction of the levator muscle, but also decreased diastolic function, i.e., ptosis retardation. In acquired cases, this is mainly due to local or diffuse muscle diseases, such as myotonic syndrome, progressive myotonic dystrophy, and myasthenia gravis.
2. Tendinous
This is caused by a fracture or rupture of the levator aponeurosis from a variety of causes, mostly spontaneous or degenerative such as age-related ptosis, but also due to trauma, internal eye surgery or rigid corneal contact lenses. In this case, the muscle strength of the levator muscle is good, with a muscle strength assessment of >8 mm and normal function of the superior rectus muscle.
3. Neurogenic
It can be caused by paralysis of the oculogyric nerve or oculogyric nerve branches and can be associated with dysfunction of one or more of the extraocular muscles innervated by the oculogyric nerve.
Sympathetic neuropathy of the neck and brainstem leads to contractile dysfunction of the Müller muscle and a smaller lid fissure. It is most commonly seen in Horner’s syndrome.
Marcus-Gunn syndrome is also known as mandibular-transient syndrome. The typical symptoms are unilateral eyelid elevation, transient eye movements, and enlarged lid fissures when opening the mouth or moving the jaw to the opposite side or chewing. The pathogenesis may be due to abnormalities in the central or subnuclear nerve fiber connections in the innervation of the external pterygoid and levator muscles, or abnormal connections between the trigeminal and oculomotor nerves in peripheral movements.
There is a lack of ideal treatment for mandibular-transient syndrome. Treatment requires testing of preoperative lid fissure size, transient values, and full communication with the patient to understand the patient’s wishes for treatment and to fully explain postoperative issues. If the preoperative transient value is <2 mm, the patient can be treated as ptosis; if the transient value is larger, the transient should be resolved before treatment.
4. Mechanical
Due to various factors causing scar-like thickening of the eyelid. It can be seen for reasons such as trauma, tumor invasion, or surgery.
5. Pseudophakic
These patients are not due to dysfunction of the affected upper eyelid lift muscle. For example, poor upper lid support due to various causes of entropion, which manifests as a smaller lid fissure; difficulty opening the upper lid due to long-term eyelid spasm; contralateral eyelid regression such as thyroid-related eye disease, which manifests as ptosis in the healthy eye; and severe lid skin laxity or redundant skin obscuring the lid margin, which manifests as ptosis. The differential diagnosis is very important for pseudophakic ptosis.
4. Preoperative evaluation of ptosis
The preoperative evaluation includes: lid margin reflectance distance (MRD), lid fissure size, levator muscle strength, upper lid lift volume, frontalis muscle strength, and Bell’s sign. Ophthalmologically relevant visual function tests, refractive status measurements, eye position and eye movement tests are also required.
1.MRD
The MRD value is an internationally accepted measure of the degree of ptosis and includes the upper lid margin corneal reflectance distance (MRD1) and the lower lid margin corneal reflectance distance (MRD2) [33]. This index quantifies ptosis and provides a more objective basis for later follow-up analysis. The MRD value is usually required to evaluate the treatment of ptosis at the time of international exchange. The MRD is the distance from the central corneal reflection to the upper eyelid margin when the patient has poor muscle strength and is unable to expose the central corneal reflection when opening the eye. The value is measured from the lower lid margin to the central corneal reflection.
2. Lid size
This can be used as an additional indicator to evaluate the degree of ptosis. The patient’s frontalis muscle is pressed with the thumb along the long axis of the eyebrows and the patient is asked to open the eyes and look at them horizontally, at which point the distance between the upper and lower lids is measured at the center of the pupil, which is the size of the lid fissure. The size of the lid fissure should also be checked when the patient is looking up and down.
3. Upper Lid Lift Muscle Strength
This test is used to evaluate the patient’s upper lid elevator muscle strength and is mainly used to select the appropriate surgical treatment plan based on the muscle strength [34]. The test is performed by pressing the frontalis muscle with the thumb along the long axis of the eyebrow and then asking the patient to look downward and then upward, at which point the distance the upper lid moves is the upper lid lift muscle strength. Usually, an upper lid lift of <4 mm is considered poor, 4 to <7 mm is moderate, 7 to <10 mm is good, and ≥10 mm is normal.
4. Upper lid lift volume
This index is the basis for the calculation of the intraoperative lid closure insufficiency value (rabbit eye value) during general anesthesia surgery. The method of detection: the examiner presses the frontalis muscle with the thumb in the direction of the long axis of the eyebrow, and then asks the patient to close the eyes and then asks the patient to look horizontally, at which point the distance the upper lid moves is the upper lid lift.
5. Bell’s sign
Bell’s sign refers to the function of the upward rotation of the eyeball when the eye is closed [3]. If the Bell sign is negative or suspicious, the intraoperative correction should be small to protect the eye. The test method: The examiner asks the patient to close the eyes easily and gently lift the upper lid in this state to observe the position of the eye.
6.Frontal muscle strength measurement
This index can provide reference value when frontal muscle related surgery is performed. Inspection method: ask the patient to look down, make a mark at the central part of the lower edge of the brow arch, then ask the patient to look up, and measure the active distance of the marker point is the frontal muscle strength.
7.Eye position detection
This is used for intraoperative and postoperative comparison to avoid changes in eye position due to ptosis surgery. This is done by asking the patient to look at a target 33 cm in front of him and observing whether the patient’s eye position is centered and symmetrical. The examiner then covers the patient’s eye and observes whether the uncovered eye rotates; then removes the cover and observes whether the uncovered eye rotates to check for strabismus.
8.Ocular movement
Preoperative testing for intraoperative and postoperative comparison. Focus on checking the function of the superior rectus muscle. If the lower edge of the cornea is lower than the level of the inner and outer canthus line when the eye is turned upward, it suggests that the function of the superior rectus muscle is weakened and the amount of surgical correction should be conservative. The examiner holds a light source about 33 cm in front of the patient and guides the patient’s eyes to six diagnostic eye positions, observing the rotation of both eyes and recording the distance between the corneal edge and the lid margin or the inner and outer canthus. Note that the subject’s head should not follow the rotation of the target during the examination.
V. Timing of ptosis surgery
The timing of surgery should vary according to the cause and severity of the condition.
1. Congenital ptosis
(1) In mild to moderate ptosis, because the pupil can be partially or fully exposed, form-deprivation amblyopia is less likely to occur, so surgery can be performed when the patient is older and can be corrected with local anesthesia, or, if psychosocial factors are taken into account, surgery can be performed at preschool age, i.e., 3 to 5 years old.
(2) Severe ptosis in one eye, where the pupil is completely obscured and the head is tilted to see, can be operated on at about 1 year of age to prevent form-deprivation amblyopia and spinal development problems.
(3) Microphthalmos syndrome, which is a severe ptosis, can be operated on at around 2 years of age. The surgery can be performed in two phases, with the inner and outer canthus shape first and the second phase of ptosis correction surgery after 6 to 12 months.
(4) Ptosis with different bilateral muscle strength is manifested by increased ptosis on the contralateral eyelid after correction of the ptosis is completed due to the Hering’s reflex. Therefore, in cases of bilateral ptosis with different muscle strengths, it is recommended to correct the more severe side first and then correct the contralateral ptosis after the eyelid shape has stabilized for about six months.
2. Acquired ptosis
(1) In traumatic ptosis, upper eyelid lift repair is feasible in the emergency phase. If the injury is old. Surgery can be considered at least 6 to 12 months after the traumatic wound has healed and the local scar tissue has softened.
(2) Tendinous ptosis can be operated on as soon as the diagnosis is made.
(3) In actinic nerve palsy, myasthenia gravis and other acquired ptosis, surgery can be considered after first treating the primary disease and waiting for the primary disease to stabilize for more than six months.
VI. Intraoperative correction volume judgment
In patients operated under local anesthesia in the sitting position, the correction should be 1 mm above the healthy side at the end of surgery, and in patients with bilateral ptosis, the upper lid should be 1 mm below the corneal margin at the end of surgery.
For patients undergoing surgery under general anesthesia, the intraoperative correction of lid closure insufficiency (rabbit eye) should be predicted preoperatively. For unilateral patients, the intraoperative “rabbit eye” value should be the amount of upper lid lift on the healthy side minus the amount of upper lid lift on the affected side when the frontalis muscle is compressed. For bilateral patients, the intraoperative “rabbit eye” value should be 9 mm minus the upper lid lift on the affected side. It is important to note that in Bell’s sign negative patients, the rabbit’s eye value should be reduced, usually to 5-7 mm, and for frontalis-related surgery, the correction should be 1 mm below the corneal limbus.
VII. Upper lid ptosis surgical options
1. Upper lid lift-related surgery using the levator muscle
Ptosis correction using the levator muscle is one of the most physiologically correct surgical procedures and often includes three types of surgery: anterior migration of the levator muscle, folding of the levator muscle, and shortening of the levator muscle. However, for severe ptosis, where the function of the levator muscle is extremely poor or absent, the choice of upper lid lift surgery can be undercorrected.
2. Surgery related to the use of the frontalis muscle
is an effective treatment supplement for patients with poor upper lid lift function. It is usually indicated when the upper lid lift muscle strength is poor or when the structure of the upper lid lift is destroyed due to trauma or surgery. Common surgical approaches include frontalis flaps, frontalis fascial flaps, and frontalis power source correction methods using autologous or allogeneic material suspensions.
3.Surgery using the Müller muscle
Theoretically, the Müller muscle is shortened by conjunctival-Müller muscle resection to increase the strength of the Müller muscle and elevate the upper lid. However, the Müller muscle is an expressive muscle, is sympathetically innervated, and is usually indicated for mild ptosis.
4. Blepharoplasty
The lid plate can be removed to elevate the upper eyelid, but it is important to keep the width of the lid plate at least 5 mm, and it can be used for mild ptosis alone, or in combination with levator shortening for moderate to severe ptosis. However, in addition to the lid’s role in eyelid support, the lid glands secrete lipids that are an important component of the normal function of the tear film, and tear stability and compensatory function after blepharoplasty need to be further explored.
5. Surgery using the combined fascial sheath of the levator palpebrae and superior rectus muscle (CFS)
The CFS is the fascial tissue between the superior rectus and superior levator muscles, and in patients with severe ptosis, this structure can be sutured to the lid to enhance suspension. However, because this fascia is associated with the superior rectus and superior rectus muscles, suture fixation is prone to superior rectus dysfunction and close intraoperative observation is required to avoid this. Complications of diplopia and inferior strabismus need to be closely observed in the postoperative period.
For the selection of the above procedure, the choice is based primarily on the muscle strength of the levator muscle.
(1) When the amount of muscle strength assessed is ≥7 mm and the patient presents with only mild ptosis, correction is mostly performed by anterior migration of the levator muscle and shortening of the levator muscle, and correction using simple lid resection or conjunctival-Müller muscle resection has also been reported.
(2) When the amount of muscle strength assessed is 4 to <7 mm and the patient presents with moderate ptosis, most often a better correction can be achieved with upper lid levator shortening.
(3) When the muscle strength assessment is <4 mm and the patient presents with severe ptosis, correction may be attempted with an upper lid lift shortening procedure, and if this is inadequate, correction may be combined with lid removal, and if still inadequate, surgical correction may be continued with a combined fascial sheath procedure. If a better correction is not obtained at this time, or if the preoperative muscle strength of the levator muscle is extremely poor, with an assessment of <1 mm, then correction can be performed with frontalis-related surgery.
Alternatively, the intraoperative correction can be evaluated preoperatively and used as a basis for deciding on the surgical approach. Intraoperatively, the anterior migration of the levator muscle is performed first, and if the amount of correction does not reach the preoperative assessment, then the levator shortening is continued, and if the amount of correction does not reach the assessment, then the combined levator shortening with CFS suspension is continued. The final combined procedure can cover most patients with ptosis including severe ptosis.
VIII. Postoperative care for ptosis
Immediately after surgery, incomplete lid closure >2 mm and a negative or suspicious positive Bell’s sign suggest a Frost suture in the lower lid to close the upper and lower lids.
Eye ointment is applied to the affected eye to protect it and the lower lid margin suture is pulled up to close the upper and lower lids and iced with an eye protection ice pack, which is maintained until the second postoperative day. After removal of the dressing on postoperative day 3, the patient was instructed to moisten the eye with eye drops 4 times/d during the day and to apply eye ointment at night to protect the eye, with the lower lid margin suture assisting in closing the lid. This care process continues until the patient’s cornea is not exposed during nighttime sleep.
If there are symptoms of exposure keratitis due to improper care, additional restorative eye drops that promote corneal cell growth are required.
IX. Ptosis complications and management
Ptosis surgery is a complex procedure with a high incidence of complications and often requires multiple surgeries to obtain good surgical results, requiring adequate communication and understanding with the patient prior to surgery. Common surgical complications, their clinical manifestations, causes and management principles are listed in the table below.