What Is Ptosis?

Ptosis is an uncommon condition that mainly affects the upper eyelid and the eyelid muscle. The severity of the condition varies from a slight droop of the eyelid skin to excess eyelid skin completely covering the pupil and obstructing vision.

Ptosis is a medical condition where the upper eyelid of one, or sometimes both eyes, droops or sags. This condition can be either congenital and apparent at birth or within the first year of life, or acquired later in life due to the aging process, trauma, or other medical conditions. If ptosis develops in one eye it is called unilateral ptosis, if both eyes are affected it is bilateral ptosis.

Read on to learn about the different types of ptosis and the many causes, discover the signs and symptoms, how ptosis is diagnosed and managed and the treatment options available. Risk factors will also be discussed later in the article. Can ptosis be fixed with ptosis repair surgery? Can eye surgery, such as cataract surgery even be a risk factor for developing this eye muscle disease? Normal vision is something we often take for granted and any eye condition, particularly one that causes vision problems can be extremely distressing.

Overview

The term ‘ptosis’ comes from the Greek meaning ‘falling’ or ‘dropped’ and is often associated with other conditions that affect the muscular and nervous systems.¹ Often, ptosis is associated with eye muscle disease. It can be congenital and present at birth or can be caused by trauma, or be associated with the general aging process.²

Causes of ptosis

There are two broad categories of ptosis, ‘true ptosis’ and ‘pseudoptosis’.²

True ptosis can be a congenital condition, meaning it is present at birth or presents within the first year of life, or can be an acquired condition that develops later on in life.^1,2

Congenital ptosis occurs during the development of the eye muscle, levator palpebrae superioris, (the muscle which raises the upper eyelid and maintains its position) is somehow impaired.¹
Causes of congenital ptosis

Underlying causes for congenital ptosis include:¹

• Simple congenital ptosis: idiopathic or unknown cause
• Congenital ptosis along with superior rectus muscle weakness: this is known as double-elevator palsy
• Marcus Gunn Jaw-winking ptosis: also known as congenital synkinetic ptosis
• Blepharophimosis Syndrome
• Third cranial nerve palsy
• Horner Syndrome
• Birth trauma
• Periorbital tumors: abnormal growths around the eyeball
• Pseudotumor of the orbit: an inflammatory process within the bony cavity containing the eyeball³

Causes of acquired ptosis

There are five types of acquired ptosis as discussed below.

• Aponeurotic ptosis – One of the most common causes of mild to moderate ptosis in the elderly. This is related to age-related degeneration, chronic inflammation, surgery trauma, or hard contact lens wear
• Myogenic ptosis – This muscle dysfunction is caused by the following rare diseases including Myasthenia gravis, myotonic dystrophy, facioscapulohumeral muscular dystrophy, oculopharyngeal muscular dystrophy, congenital myopathies, chronic progressive external ophthalmoplegia, and mitochondriopathy⁴
• Neurogenic ptosis – This is caused by damage to the oculomotor (third cranial nerve) or sympathetic nerves, or to the central nervous system. More indirect causes of neurogenic ptosis are diabetes, tumors, carotid cavernous aneurysms, and multiple sclerosis
• Mechanical ptosis – This is when the eyelid has become too heavy for the muscles to be able to function and keep it elevated
• Traumatic ptosis – as a result of traumatic injury

Pseudoptosis

This is when the eyelid appears to be drooping but is unrelated to any neurological or musculoskeletal eyelid defects.⁵ Pseudoptosis may be caused by an abnormal-sized eye or other factors that do not relate to the eyelid mechanisms.

Signs and symptoms of ptosis

• Drooping of the eyelid is the main sign and this can vary between individuals
• Head tilting to see under the eyelid
• Repeatedly raising the eyebrow to lift the eyelid
• The affected eye appears smaller
• Other symptoms relating to the underlying conditions
• Impaired vision 
• Dry eyes

Management and treatment for ptosis

Management and treatment of ptosis will depend on the cause of the condition, the severity of the effects, and the functioning of the muscle involved. Ptosis treatment may not be necessary if the ptosis is slight and not interfering with vision.

• Stimulation of the muscle by exercising the muscle using electrical or mechanical stimulation⁶
• Administration of medicated eye drops⁶
• Taping up of the brow or eyelid to improve vision or a ptosis crutch⁶
• Surgery is appropriate for congenital ptosis and where non-surgical treatments are not appropriate^1,2

Diagnosis of ptosis

The following measurements are used to assess ptosis.⁷

• Levator muscle function
• Margin-reflex distance: distance between the upper lid margin and the corneal light reflection (when shining a torchlight to the eyes by your doctor or the examiner)
• Palpebral fissure height: distance between the upper lid margin and the lower lid margin
• Margin crease distance: distance between the skinfold of the upper eyelid and the upper eyelid margin

Risk factors

Being middle-aged or elderly is the main risk factor for developing ptosis. The following can also increase the chances of developing this condition.

• Injury or stretching of eyelid muscles or ligaments
• Damage to the nerve controlling the eyelid muscles
• Complications of eye surgery
• Genetic factors
• Accidental stretching or tearing of the levator muscle
• Contact lenses
• Eye rubbing
• Other underlying health conditions

FAQs

Can ptosis be prevented?

It is important to be aware of the risk factors and underlying health conditions that are associated with ptosis, but in most cases, this condition cannot be prevented.

How common is ptosis?

Congenital ptosis is the most common form of this condition, and the most common type of acquired ptosis is aponeurotic. There isn’t enough data on the incidence of ptosis to offer statistical figures, but it isn't a very common condition.

When should I see a doctor?

Make an appointment with your doctor if you notice any drooping of your eyelid, however severe. Any problems with vision or discomfort in the eye should be investigated by a medical professional. It is also important to monitor other underlying health conditions that may be risk factors in the development of ptosis. If you are a parent of a newborn or a young baby, then any unusual appearance of the eye should be investigated by a doctor.

Summary

Ptosis is not a very common condition, and some of the causes of ptosis are very rare. The main characteristic of ptosis is the drooping of the upper eyelid, and treatment will depend on the severity of the drooping and the impact on vision and appearance. An eye specialist will be able to diagnose and manage the condition.