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.

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.

Ptosis can be caused by the aponeurosis of the levator muscle, nerve abnormalities, trauma, inflammation or lesions of the lid or orbit.

[5] Ptosis may be attributable to a myogenic, neurogenic, aponeurotic, mechanical or traumatic cause, and it usually occurs in an isolated manner.

Ingestion of high doses of opioid drugs such as morphine, oxycodone, heroin or hydrocodone can cause ptosis.

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.

[9] Another mechanism is the disturbance of the oculomotor nerve causing the levator palpebrae to weaken, resulting in the eyelid drooping.

[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.

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.

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.

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.

[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 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.

Many slings in the market today include monofilament nylon, silicone rods, polyester, silk, collagen, stainless steel, or polypropylene.

[15] The levator function measures the distance the eyelid travels, starting with the downgaze movement to the upgaze without moving the frontalis muscle.

In 2020, the United States Food and Drug Administration approved a 0.1% oxymetazoline hydrochloride ophthalmic solution for acquired blepharoptosis.

Oxymetazoline is believed to work by stimulating the α1 and α2 adrenergic receptors of Müller's muscle, which helps to lift the eyelid and improve vision.

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.

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.

[27] 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."