oculomotor nerve palsy

Fourth cranial nerve palsy or trochlear nerve palsy is a condition affecting cranial nerve 4 IV the trochlear nerve which is one of the cranial nervesIt causes weakness or paralysis of the superior oblique muscle that it innervates. As a result trochlear.

Neuro Cranial Nerve 3 Palsy Cranial Nerves Nerve Palsy Cranial Nerve 3

If there is any oculomotor nerve impairment there will be a pupillary dilation ptosis drooping eyelid and outward deviation of the eye termed abduction.

. Because the causes of sixth nerve palsy are legion and the evaluation of such patients is extensive and expensive the examiner should first rule out causes of pseudo-sixth nerve palsy Conditions that also produce abduction failure include Duanes syndrome spasm of the near reflex myasthenia gravis and thyroid. In most cases third nerve palsy resolves over weeks to months. It is caused by a lower motor neuron lesion in the medulla oblongata or from lesions to these nerves outside the brainstem. Oculomotor nerve palsy can also cause ptosis due to a loss of innervation to levator palpebrae superioris as well as mydriasis due to the loss of parasympathetic fibres responsible for innervating to the sphincter pupillae muscle.

This condition often causes vertical or near vertical double vision as the weakened muscle prevents the eyes from moving in the same direction together. Trochlear nerve palsy CN IV The only muscle the trochlear nerve innervates is the superior oblique muscle. When a patient has diplopia double vision it is often due to a unilateral lesion on this cranial nerve. Bulbar palsy refers to a range of different signs and symptoms linked to impairment of function of the glossopharyngeal nerve CN IX the vagus nerve CN X the accessory nerve CN XI and the hypoglossal nerve CN XII.