What is ptosis, droopy eyelid?
Also known as the drooping eyelid, ptosis or blepharoptosis is a condition in which the border of the upper eyelid of one or both eyes falls to a lower position than normal. When droopy eyelid affects only one eye, it is called unilateral ptosis while in bilateral blepharoptosis both eyes get affected by drooping eyelids.
Pathological drooping of the eyelids may occur due to age, trauma, or several medical disorders. Ptosis might be temporary or permanent, and it can be present at birth or can develop later in life. Based on this, blepharoptosis is classified as below:
Droopy eyelid: types and ptosis causes
Congenital droopy eyelid is associated with congenital maldevelopment of the levator palpebrae superioris (LPS) muscle. It is of four types: simple congenital ptosis, congenital ptosis with associated weakness of superior rectus muscle, blepharophimosis syndrome, and congenital synkinetic ptosis.
A simple congenital drooping eyelid is not associated with any other anomaly. But, blepharophimosis syndrome is comprised of congenital ptosis, blepharophimosis, telecanthus, and epicanthus inversus.
Similarly, congenital synkinetic ptosis is also known as Mascus Gunn jaw winking ptosis and there occurs retraction of the ptotic lid jaw with jaw movements.
Acquired ptosis develops later in life. It is classified as neurogenic, myogenic, aponeurotic, and mechanical ptosis.
Neurogenic ptosis occurs with the problem of nerve supply to the LPS muscle. It can be either due to third cranial nerve palsy, Horner’s syndrome, or multiple sclerosis.
Myogenic ptosis occurs due to the problem in the LPS muscle itself or in the myoneural junction as in the case of myasthenia gravis, myotonic dystrophy, or trauma to the LPS muscle.
Aponeurotic ptosis happens due to the problem in the connection of LPS to the tarsal plate. It is the most common type of ptosis seen in adults, especially in old age. Clinically the eyelid crease is absent in severe ptosis and often elevated in mild ptosis.
It is the type of acquired ptosis which occurs due to excessive weight on the upper eyelid such as tumor, edema, dermatochalasis, or anterior orbital lesions.
If there is the appearance of ptosis without levator abnormality, it is called pseudoptosis. The common causes of pseudoptosis are anophthalmos, microphthalmos, enophthalmos, phthisis bulbi, blepharospasm, double elevator palsy, contralateral proptosis, dermatochalasis, and Duane’s syndrome.
Signs and symptoms of ptosis
The main symptom of ptosis is the droopy or falling of one or both upper eyelids. It is a painless condition. So, it may go unnoticed in many cases of mild ptosis. The more severe the ptosis gets more it impacts the appearance of the face. Hence, it may cause a psychological impact as well.
You won’t notice any other symptoms if you have mild, uncomplicated ptosis. However, if the ptosis is caused by a serious medical illness, you may find other symptoms related to the underlying cause.
For example, if you have double vision, difficulty speaking, swallowing or breathing, and weakness in the limbs along with droopy eyelid, you may be suffering from myasthenia gravis. Likewise, infants with congenital ptosis might have crossed eyes, lazy eye, and/or nystagmus.
If ptosis covers part of your pupil and limits the visibility, you might try raising your eyelids unconsciously. As a result, tension-type headache, and chin up are common in patients with severe ptosis.
Evaluation of Ptosis
Proper ptosis evaluation is essential to measure the amount of ptosis and can help to successful management of the droopy eyelid. Clinical evaluation of ptosis involves history taking and accurate measurement of margin to reflex distance (MRD), levator function, palpebral fissure height, and superior lid crease.
In history taking, there are five main things to focus on. The onset of ptosis, the family history, history of trauma, history of eye surgery, and variability in the degree of ptosis.
In the clinical evaluation of ptosis, it is necessary to exclude the pseudoptosis and observe if there is a unilateral or bilateral occurrence. Similarly, the function of orbicularis oculi muscle should be observed carefully as its function is to close the eyelid. The important landmark to notice is the presence or absence of eyelid crease.
It is also necessary to check the jaw-winking phenomenon: the winking motion of the affected eyelid on the movement of the jaw. Another two important things to consider are the associated weakness of any extraocular muscle and the Bell’s phenomenon (an upward and outward movement of the eye while attempting to close the eye).
Now, it’s time to measure the amount of ptosis. The distance between upper eyelid margin and pupillary light reflex (i.e. marginal reflex distance) is measured using a millimeter scale. It measures how much corneal area is covered by the upper lid. Based on this reading, the severity of ptosis is determined.
- Normal (MRD): less than 2 mm
- Mild ptosis: 2 mm of eyelid droop
- Moderate ptosis: 3-4 mm of droop
Severe ptosis: more than 4 mm of droop (at this stage, the eyelid starts covering the pupil, hence affect vision)
Similarly, the function of LPS should be assessed after the MRD measurement. The examiner holds the patient’s eyebrow with the left hand to prevent the frontalis muscle action. The patient is asked to look down and then to look up. Now, the distance between the lower and upper gaze is measured to determine the ability of LPS to lift the eyelid. The ideal distance should be 12 mm.
- More than 8 mm: good LPS function
- 4-8 mm: moderate function
- Less than 4 mm: very poor LPS function
Droopy eyelid, ptosis treatment
Surgical correction is the mainstay of treatment in congenital ptosis. Surgery should be performed as earlier as possible in severe ptosis to prevent stimulus deprivation amblyopia.
However, surgery can be delayed until the age of 3-5 years in mild to moderate droopy eyelids. The surgical procedures common in ptosis surgery are conjunctive-muller resection, levator resection, and brow suspension.
Plastic surgery is the available surgical option to raise the eyelids in age-related ptosis. This procedure is done under local anesthesia. The surgery is desirable mainly for cosmetic purposes and sometimes to fix visual impairments.
If a person doesn’t want to undergo surgery, special types of glasses are available to correct the droopy eyelid to some extent. The eyeglasses are made with a crutch (ptosis crutch) attachment that can hold up the eyelid.
The ptosis caused by muscle disease, the neurological problems of local eye problems, your doctor will treat the underlying cause which subsequently reduces the effect of a droopy eyelid.
The prognosis of the ptosis surgery is good. In some cases, the eyes may remain open slightly during sleep after surgery. So, it is advised to put nighttime lubricating eye drops or gel to prevent drying of eyes.