Ptosis (eyelid)

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Ptosis of the eyelids
1852 ptosis patient.jpg
Ptosis of the left eyelid (unilateral ptosis). A headshot daguerreotype of an unidentified male, by William Bell in 1852.
Pronunciation
Specialty Ophthalmology, optometry, neurology

Ptosis, also known as blepharoptosis, [1] is a drooping or falling of the upper eyelid. This condition is sometimes called "lazy eye", but that term normally refers to the condition amblyopia. If severe enough and left untreated, the drooping eyelid can cause other conditions, such as amblyopia or astigmatism, so it is especially important to treat the disorder in children before it can interfere with vision development.

Contents

The term is from Greek πτῶσις 'fall, falling'.

Signs and symptoms

Early fourteenth-century manuscript initial showing King Edward I of England and his wife Eleanor of Castile. The artist has depicted Edward's blepharoptosis, a trait he inherited from his father, King Henry III. Edward I and Eleanor.jpg
Early fourteenth-century manuscript initial showing King Edward I of England and his wife Eleanor of Castile. The artist has depicted Edward's blepharoptosis, a trait he inherited from his father, King Henry III.

Signs and symptoms typically seen in this condition include: [2]

Some of the risk factors for ptosis include:

Causes

Neurotoxic ptosis caused by botulinum toxin: a 14-year-old botulism patient with bilateral total ophthalmoplegia with ptosis (left image) and dilated, fixed pupils (right image). The teenager was fully conscious Botulism1and2.JPG
Neurotoxic ptosis caused by botulinum toxin: a 14-year-old botulism patient with bilateral total ophthalmoplegia with ptosis (left image) and dilated, fixed pupils (right image). The teenager was fully conscious
Phineas Gage displayed ptosis after surgery to treat wounds inflicted by a large iron rod entering his left cheek, passing behind his left eye, and exiting at the top of his head Phineas Gage GageMillerPhoto2010-02-17 Unretouched Color Cropped.jpg
Phineas Gage displayed ptosis after surgery to treat wounds inflicted by a large iron rod entering his left cheek, passing behind his left eye, and exiting at the top of his head

Ptosis occurs as the result of dysfunction of the muscles that raise the eyelid or their nerve supply (oculomotor nerve for levator palpebrae superioris and sympathetic nerves for superior tarsal muscle). It can affect one eye or both eyes and is more common in the elderly, as muscles in the eyelids may begin to deteriorate. Babies may also exhibit ptosis at birth as the result of abnormal development of the levator muscle while the child is in the mother's womb. Congenital ptosis is hereditary in three main forms. [3]

Causes of congenital ptosis remain unknown. Ptosis may be caused by damage to the muscle that raises the eyelid, damage to the superior cervical sympathetic ganglion or damage to the oculomotor nerve, which controls the muscle. Such damage could be a sign of an underlying disease such as diabetes mellitus, a brain tumor, a pancoast tumor (apex of the lung) and diseases that cause weakness in muscles or nerve damage, such as myasthenia gravis or oculopharyngeal muscular dystrophy. Exposure to the toxins in some snake venoms, such as that of the black mamba, may also cause this effect.

Ptosis can be caused by the aponeurosis of the levator muscle, nerve abnormalities, trauma, inflammation or lesions of the lid or orbit. [4] Dysfunctions of the levators may occur as a result of autoimmune antibodies attacking and eliminating the neurotransmitter. [5]

Ptosis may be attributable to a myogenic, neurogenic, aponeurotic, mechanical or traumatic cause, and it usually occurs in an isolated manner. However, it may be associated with various other conditions, such as immunological, degenerative or hereditary disorders as well as tumors or infections. [6]

Acquired ptosis is most commonly caused by aponeurotic ptosis. This can occur because of senescence, dehiscence or disinsertion of the levator aponeurosis. Moreover, chronic inflammation or intraocular surgery can lead to the same effect. Also, wearing contact lenses for long periods is thought to have a certain impact on the development of the condition.

Congenital neurogenic ptosis is believed to be caused by Horner's syndrome, [4] in which a mild ptosis may be associated with ipsilateral ptosis, iris and areola hypopigmentation and anhidrosis caused by paresis of the superior tarsal muscle. Acquired Horner syndrome may result after trauma, neoplastic insult or even vascular disease.

Ptosis caused by trauma can ensue after an eyelid laceration with transection of the upper eyelid elevators or disruption of the neural input. [4]

Other causes of ptosis include eyelid neoplasms, neurofibromas or cicatrization after inflammation or surgery. Mild ptosis may occur with aging. A drooping eyelid can be one of the first signals of a third-nerve palsy resulting from a cerebral aneurysm that is otherwise asymptomatic, a condition known as oculomotor nerve palsy.

Drugs

Ingestion of high doses of opioid drugs such as morphine, oxycodone, heroin or hydrocodone can cause ptosis. [7] Pregabalin, an anticonvulsant drug, has also been known to cause mild ptosis. [8]

Mechanism

Different trauma can cause and induce many different mechanisms. For example, myogenic ptosis results from a direct injury to the levator muscle and/or Müller's muscle. On the other hand, neurogenic ptosis is caused by closed head injuries or traumatically introduced neurotoxin (wasp/bee/snake venom) or botulinum toxin due to the effect of those factors on the CNIII or the sympathetic pathway. Mechanical ptosis can also occur due to scarring tissue restricting the patient's eyelid excursion or weighing down the patient's lid. [9] Another mechanism is the disturbance of the oculomotor nerve causing the levator palpebrae to weaken, resulting in the eyelid drooping. Ptosis can also occur in a patient with brain tumors due to pressure on the third nerve, also known as the sympathetic nerve, on the brainstem.

Pathology

Myasthenia gravis is a common neurogenic ptosis that could also be classified as neuromuscular ptosis because the site of pathology is at the neuromuscular junction. Studies have shown that up to 70% of myasthenia gravis patients present with ptosis, and 90% of these patients will eventually develop ptosis. [10] In this case, ptosis can be unilateral or bilateral, and its severity tends to be oscillating during the day, because of factors such as fatigue or drug effect. This particular type of ptosis is distinguished from the others with the help of a Tensilon test and blood tests. Also specific to myasthenia gravis is the fact that coldness inhibits the activity of cholinesterase, which makes it possible to differentiate this type of ptosis by applying ice onto the eyelids. Patients with myasthenic ptosis are likely to experience a variation in the drooping of the eyelid at different hours of the day.

Ptosis caused by oculomotor palsy can be unilateral or bilateral, as the subnucleus to the levator muscle is a shared midline structure in the brainstem. In cases where the palsy is caused by the compression of the nerve by a tumor or aneurysm, it is highly likely to result in an abnormal ipsilateral papillary response and a larger pupil. Surgical third nerve palsy is characterized by a sudden onset of unilateral ptosis and an enlarged or sluggish pupil to the light. In this case, imaging tests such as CTs or MRIs should be considered. Medical third nerve palsy, contrary to surgical third nerve palsy, usually does not affect the pupil and tends to improve in several weeks slowly. Surgery to correct ptosis due to medical third nerve palsy is normally considered only if the improvement of ptosis and ocular motility are unsatisfactory after half a year. Patients with third nerve palsy tend to have a diminished or absent function of the levator.

When caused by Horner's syndrome, ptosis is usually accompanied by miosis and anhidrosis. In this case, the ptosis is due to interruption innervations to the sympathetic, autonomic Muller's muscle rather than the somatic levator palpebrae superioris muscle. The lid position and pupil size are typically affected by this condition, and the ptosis is generally mild, no more than 2  mm. The pupil might be smaller on the affected side. While 4% cocaine instilled in the eyes can confirm the diagnosis of Horner's syndrome, Hydroxyamphetamine eye drops can differentiate the location of the lesion. [10]

Chronic progressive external ophthalmoplegia is a systemic condition that usually affects only the lid position and the external eye movement without involving the movement of the pupil. This condition accounts for nearly 45% of myogenic ptosis cases. Most patients develop ptosis due to this disease in their adulthood. A characteristic of ptosis caused by this condition is that the protective uprolling of the eyeball when the eyelids are closed is very poor.

Diagnosis

A doctor will first perform a physical exam with questions about the patient's medical history to distinguish whether the condition may be hereditary. A slit lamp exam is performed with a high-intensity light that allows a close look at the patient's eyes. The doctor can also perform a test in which edrophonium is injected into a vein, and the eyelids are monitored for resulting signs of improvement.

A visual field test may be performed, which assesses the degree to which the ptosis affects the superior vision. Because nerve damage is among the possible causes of ptosis, the ophthalmologist will check the patient's pupil for abnormalities. The doctor will also check muscle function.

The ophthalmologist may also measure the degree of the eyelid droop by measuring the marginal reflex distance, which is the distance between the center of the pupil and the edge of the upper lid, as well as the strength and function of the patient's levator muscle. This test entails holding the frontalis muscle to measure how far the eyelid travels when the patient is gazing downward.

Through these tests, the ophthalmologist may properly diagnose ptosis and identify its classification, and a determination may be made regarding the course of treatment, which may involve surgery. [11]

Classification

Mild right eyelid ptosis Congenitalptosis.JPG
Mild right eyelid ptosis

Depending upon the cause, ptosis may be classified into:

Hollywood actor Forest Whitaker has a left eye ptosis Forest Whitaker Cannes 2013 3.jpg
Hollywood actor Forest Whitaker has a left eye ptosis

Treatment

Aponeurotic and congenital ptosis may require surgical correction if severe enough to interfere with the vision or if appearance is a concern. Treatment depends on the type of ptosis and is usually performed by an ophthalmic plastic surgeon or a reconstructive surgeon specializing in diseases and eyelid problems.

If the condition occurs in a child, the doctor will delay the surgery until the patient is 4 or 5 years old. If the patient is under the recommended age for surgery, the doctor will test if occlusion therapy can compensate for the patient's impeded vision. The reason for delaying the surgery until the patient is at least 4–5 years of age is the necessity of delay for the frontonasal and upper face to complete their complex growth. After this complex growth is complete, the doctors can obtain a more accurate measurement of the conditions. However, surgery will be needed sooner if the patient's vision impediment worsens or proves unresponsive to the occlusion therapy. [15]

Surgical procedures include:

The frontalis sling surgery can only be done if the patient's ptosis condition is due to diseased or stretched-out muscles. The stretching-out of muscle is due to age. The frontalis sling surgery is done to either tighten or shorten the affected muscles, thereby allowing the process to raise the patient's lid's resting position. The procedure is done with the doctor using the sling to loop the material, then threading it underneath the patient's eyebrows and above the lashes. [16] Once the sling has been tightened, this allows the patient's forehead's muscle to aid in lifting the lid. The sling can be looped in a pentagon or triangle (singular or double) shape. Many slings in the market today include monofilament nylon, silicone rods, polyester, silk, collagen, stainless steel, or polypropylene. [15]

Frontalis sling surgery is considered the most effective surgical treatment for moderate to severe congenital ptosis. [17] Many different materials can be used for the surgery, though it is currently unclear which material has the highest success rate.

The levator resection and advancement surgery should only be considered for patients who are experiencing a levator function less than or equal to 5 mm. [15] The levator function measures the distance the eyelid travels, starting with the downgaze movement to the upgaze without moving the frontalis muscle. [18] Although this procedure can be completed through two different approaches, the internal and the external, the external approach allows the surgeons to obtain a better view of the surgical site during the procedure. The surgeon will begin with an incision on the eyelid. Once the levator has been exposed, the surgeon either folds it or cuts it off before suturing it to the tarsal plate. During this procedure, it is up to the surgeon to decide the height and the contour of the patient's eyelid, with input from the patient.

The Whitnall sling procedure is done with an incision from the levator to the Whitnall ligament. Then the surgeon will suture the Whitnall's ligament connecting it to the superior tarsal edge. This procedure most likely is done if the patients are concerned about cosmetic appearance. The Whitnall sling procedure is able to provide a better cosmetic result because the procedure is able to keep the Whitnall's ligament intact. This allows the support of the lacrimal gland and temporal eyelid to be maintained. [19]

Despite the gains the patient can obtain from the surgeries, there are risk factors. After the surgery, the patient may experience asymmetrical (uneven) eyelids. If the surgery is not done carefully, the patient may experience dry eyes because the eye is no longer closing fully. The patient may also experience bleeding after the surgery and infections if the surgical site is not taken care of properly. [20] On rare occasions, the patient will experience a loss in eyelid movement. [21]

Non-surgical modalities like the use of "crutch" glasses or ptosis crutches or special scleral contact lenses to support the eyelid may also be used.

Ptosis that is caused by a disease may improve if the disease is treated successfully, although some related diseases, such as oculopharyngeal muscular dystrophy, currently have no cures.

Prognosis

If the ptosis is left untreated, patients may experience amblyopia, also known as lazy eye, which can permanently damage the patient's vision. [20] After careful observation and planning from specialists, ptosis can be successfully treated. Treatment like surgery will allow the patient to begin experiencing improvement in vision as well as cosmetic results. In a study of patients who were previously treated for ptosis, half required additional surgery within 8 to 10 years of the first surgery. If the ptosis is not related to major health issues (such as cancerous tumors or traumatic injuries), the condition will not shorten the patient's life expectancy. [22]

Complications

Ptosis can lead to various complications, including refractive errors. When ptosis obstructs the upper field of vision, affected individuals may compensate by tilting their head back or raising their eyebrows, which can result in astigmatism or other refractive errors due to the altered positioning of the eye. Additionally, ptosis can lead to eye strain and fatigue, potentially exacerbating existing refractive errors such as myopia or hyperopia. Early detection and management of ptosis, often through surgical correction, are essential to minimize these complications and ensure optimal visual health. [23]    

Epidemiology

According to ophthalmology studies done on ptosis patients, occurrence rates are as follows. The average age for females experiencing aponeurotic ptosis is 67.83 years, and the corresponding male average age is 68.19. The average age for congenital ptosis is 12.27 years for females and 8.57 years for males. The average age for mechanical ptosis is 49.41 years in females and 43.30 years in males. The average age for myogenic ptosis is 53.45 for females and 43.30 for males. The average age for neurogenic ptosis is 43.6 years in females and 32.62 years in males. Lastly, the average age for traumatic ptosis is 35.12 years in females and 33.4 years in males. [24] Ptosis was not found to have any overall gender or racial preference. [25]

Research directions

Current studies have indicated that previous methods, such as occlusion therapy and surgery, are considered the most appropriate for treating this condition. Further studies are encouraged to be able to determine the optimal surgical indications. Any discoveries on approaches with dry eye will help further the oculoplastic surgeries. [26]

Etymology

Ptosis is derived from the Greek word πτῶσις (ptōsis, "fall"), and is defined as the "abnormal lowering or prolapse of an organ or body part."

See also

Related Research Articles

<span class="mw-page-title-main">Oculomotor nerve</span> Cranial nerve III, for eye movements

The oculomotor nerve, also known as the third cranial nerve, cranial nerve III, or simply CN III, is a cranial nerve that enters the orbit through the superior orbital fissure and innervates extraocular muscles that enable most movements of the eye and that raise the eyelid. The nerve also contains fibers that innervate the intrinsic eye muscles that enable pupillary constriction and accommodation. The oculomotor nerve is derived from the basal plate of the embryonic midbrain. Cranial nerves IV and VI also participate in control of eye movement.

<span class="mw-page-title-main">Eyelid</span> Thin fold of skin that covers and protects the eye

An eyelid is a thin fold of skin that covers and protects an eye. The levator palpebrae superioris muscle retracts the eyelid, exposing the cornea to the outside, giving vision. This can be either voluntarily or involuntarily. "Palpebral" means relating to the eyelids. Its key function is to regularly spread the tears and other secretions on the eye surface to keep it moist, since the cornea must be continuously moist. They keep the eyes from drying out when asleep. Moreover, the blink reflex protects the eye from foreign bodies. A set of specialized hairs known as lashes grow from the upper and lower eyelid margins to further protect the eye from dust and debris.

<span class="mw-page-title-main">Horner's syndrome</span> Facial disorder due to damage of the sympathetic nerves

Horner's syndrome, also known as oculosympathetic paresis, is a combination of symptoms that arises when a group of nerves known as the sympathetic trunk is damaged. The signs and symptoms occur on the same side (ipsilateral) as it is a lesion of the sympathetic trunk. It is characterized by miosis, partial ptosis, apparent anhidrosis, with apparent enophthalmos.

<span class="mw-page-title-main">Duane syndrome</span> Rare congenital disease characterized by external gaze palsy

Duane syndrome is a congenital rare type of strabismus most commonly characterized by the inability of the eye to move outward. The syndrome was first described by ophthalmologists Jakob Stilling (1887) and Siegmund Türk (1896), and subsequently named after Alexander Duane, who discussed the disorder in more detail in 1905.

<span class="mw-page-title-main">Levator palpebrae superioris muscle</span> Muscle in orbit that elevates upper eyelid

The levator palpebrae superioris is the muscle in the orbit that elevates the upper eyelid.

<span class="mw-page-title-main">Extraocular muscles</span> Seven extrinsic muscles of the human eye

The extraocular muscles, or extrinsic ocular muscles, are the seven extrinsic muscles of the human eye. Six of the extraocular muscles, the four recti muscles, and the superior and inferior oblique muscles, control movement of the eye and the other muscle, the levator palpebrae superioris, controls eyelid elevation. The actions of the six muscles responsible for eye movement depend on the position of the eye at the time of muscle contraction.

<span class="mw-page-title-main">Anisocoria</span> Unequal size of the eyes pupils

Anisocoria is a condition characterized by an unequal size of the eyes' pupils. Affecting up to 20% of the population, anisocoria is often entirely harmless, but can be a sign of more serious medical problems.

Ocular myasthenia gravis (MG) is a disease of the neuromuscular junction resulting in hallmark variability in muscle weakness and fatigability. MG is an autoimmune disease where anomalous antibodies are produced against the naturally occurring acetylcholine receptors in voluntary muscles. MG may be limited to the muscles of the eye, leading to abrupt onset of weakness/fatigability of the eyelids or eye movement. MG may also involve other muscle groups.

<span class="mw-page-title-main">Congenital fourth nerve palsy</span> Medical condition

Congenital fourth nerve palsy is a condition present at birth characterized by a vertical misalignment of the eyes due to a weakness or paralysis of the superior oblique muscle.

<span class="mw-page-title-main">Superior tarsal muscle</span>

The superior tarsal muscle is a smooth muscle adjoining the levator palpebrae superioris muscle that helps to raise the upper eyelid.

<span class="mw-page-title-main">Hypertropia</span> Condition of misalignment of the eyes

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Blepharochalasis is an inflammation of the eyelid that is characterized by exacerbations and remissions of eyelid edema, which results in a stretching and subsequent atrophy of the eyelid tissue, leading to the formation of redundant folds over the lid margins. It typically affects only the upper eyelids, and may be unilateral as well as bilateral.

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<span class="mw-page-title-main">Oculomotor nerve palsy</span> Medical condition

Oculomotor nerve palsy or oculomotor neuropathy is an eye condition resulting from damage to the third cranial nerve or a branch thereof. As the name suggests, the oculomotor nerve supplies the majority of the muscles controlling eye movements. Damage to this nerve will result in an inability to move the eye normally. The nerve also supplies the upper eyelid muscle and is accompanied by parasympathetic fibers innervating the muscles responsible for pupil constriction. The limitations of eye movement resulting from the condition are generally so severe that patients are often unable to maintain normal eye alignment when gazing straight ahead, leading to strabismus and, as a consequence, double vision (diplopia).

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Chronic progressive external ophthalmoplegia (CPEO) is a type of eye disorder characterized by slowly progressive inability to move the eyes and eyebrows. It is often the only feature of mitochondrial disease, in which case the term CPEO may be given as the diagnosis. In other people suffering from mitochondrial disease, CPEO occurs as part of a syndrome involving more than one part of the body, such as Kearns–Sayre syndrome. Occasionally CPEO may be caused by conditions other than mitochondrial diseases.

<span class="mw-page-title-main">Cranial nerve disease</span> Impaired functioning of one of the twelve cranial nerves

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<span class="mw-page-title-main">Roots of the ciliary ganglion</span>

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Exposure keratopathy is medical condition affecting the cornea of eyes. It can lead to corneal ulceration and permanent loss of vision due to corneal opacity.

References

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  2. ↑ "Ptosis Of The Eyelid: Symptoms, Causes, Treatments". www.eyeinstitute.co.nz. Archived from the original on 2021-04-30. Retrieved 2019-12-09.
  3. ↑ "Congenital Ptosis". MEDgle. Archived from the original on 2016-01-05. Retrieved 2008-10-20.
  4. 1 2 3 Adult Ptosis at eMedicine
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  15. 1 2 3 City, Janice Liao, MD, New York. "Ptosis: Diagnostic Tips & Surgical Options". www.reviewofophthalmology.com. Archived from the original on 2021-04-30. Retrieved 2019-12-09.{{cite web}}: CS1 maint: multiple names: authors list (link)
  16. ↑ "What is Frontalis Sling? What are the advantages and disadvantages?". American Academy of Ophthalmology. 2012-04-12. Archived from the original on 2021-04-30. Retrieved 2019-12-09.
  17. ↑ Rosenberg JB, Andersen J, Barmettler A (2019). "Types of materials for frontalis sling surgery for congenital ptosis". Cochrane Database Syst Rev. 2019 (4): CD012725. doi:10.1002/14651858.CD012725.pub2. PMC   6478334 . PMID   31013353.{{cite journal}}: CS1 maint: multiple names: authors list (link)
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  20. 1 2 "Ptosis Information and Symptoms -". 2020aec.com. Archived from the original on 2021-05-06. Retrieved 2019-12-09.
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  23. ↑ Owji, Naser; Khalili, Mohammad Reza; Bazrafkan, Hamid; Heydari, Mojtaba (3 October 2022). "Long-term outcome of refractive errors in patients with congenital blepharoptosis who have undergone ptosis surgery". Clinical and Experimental Optometry. 105 (7): 715–720. doi:10.1080/08164622.2021.1973344. PMID   34538220. S2CID   237573319.
  24. ↑ Gonzalez-Esnaurrizar, G. (2008-05-14). "The Epidemiology and Etiology of Ptosis in an Ophthalmic Center". Investigative Ophthalmology & Visual Science. 49 (13): 640. ISSN   1552-5783. Archived from the original on 2021-04-29. Retrieved 2019-12-14.
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  26. ↑ Aakalu, Vinay (2011). "Current Ptosis Management: A National Survey of ASOPRS Member" (PDF). Original Investigation. Archived (PDF) from the original on 2021-08-31. Retrieved 2019-12-14.

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