![]() ![]() 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. For example, myogenic ptosis results from a direct injury to the levator muscle and/or Müller's muscle. Mechanism ĭifferent trauma can cause and induce many different mechanisms. Pregabalin, an anticonvulsant drug, has also been known to cause mild ptosis. Ingestion of high doses of opioid drugs such as morphine, oxycodone, heroin or hydrocodone can cause ptosis. 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. Other causes of ptosis include eyelid neoplasms, neurofibromas or cicatrization after inflammation or surgery. ![]() Ptosis caused by trauma can ensue after an eyelid laceration with transection of the upper eyelid elevators or disruption of the neural input. Acquired Horner syndrome may result after trauma, neoplastic insult or even vascular disease. Also, wearing contact lenses for long periods is thought to have a certain impact on the development of the condition.Ĭongenital neurogenic ptosis is believed to be caused by Horner's syndrome, 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. Moreover, chronic inflammation or intraocular surgery can lead to the same effect. This can occur because of senescence, dehiscence or disinsertion of the levator aponeurosis. ![]() Īcquired ptosis is most commonly caused by aponeurotic ptosis. However, it may be associated with various other conditions, such as immunological, degenerative or hereditary disorders as well as tumors or infections. ![]() Ptosis may be attributable to a myogenic, neurogenic, aponeurotic, mechanical or traumatic cause, and it usually occurs in an isolated manner. Dysfunctions of the levators may occur as a result of autoimmune antibodies attacking and eliminating the neurotransmitter. Ptosis can be caused by the aponeurosis of the levator muscle, nerve abnormalities, trauma, inflammation or lesions of the lid or orbit. Exposure to the toxins in some snake venoms, such as that of the black mamba, may also cause this effect. 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. 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. Ĭauses of congenital ptosis remain unknown. Congenital ptosis is hereditary in three main forms. Babies may also exhibit ptosis at birth as the result of abnormal development of the while the child is in the mother's womb. It can affect one eye or both eyes and is more common in the elderly, as muscles in the eyelids may begin to deteriorate. 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). Phineas Gage displayed ptosis after a large iron rod entered his left cheek, passed behind his left eye, and exited at the top of his head ![]()
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