Oculomotor, trochlear and abducens nerve disorders

Introduction to eye movement, pulley and abduction neurological diseases The ocular (III), the trochle (IV) and the abduction (VI) are the motor nerves that dominate the eye muscles. Because they leave the brainstem, they travel a lot before going out. The site, therefore often causes the symptoms of the simultaneous involvement of the three pairs of cranial nerves. basic knowledge The proportion of illness: 0.001% Susceptible people: no specific people Mode of infection: non-infectious Complications:

Eye movement, trochlear and abductive neuropathy

Aneurysm (20%):

The aneurysm of the cerebral arterial ring often causes paralysis of the motor of the eye. The internal carotid artery aneurysm in the cavernous sinus can cause eye movement, stun of the trochlear, abductor nerve and trigeminal nerve branch, called cavernous sinus syndrome, posterior cerebral artery The upper cerebellar artery and the posterior communicating artery aneurysm can cause oculomotor nerve palsy, oculomotor palsy caused by aneurysm, almost all with pupil dilation and fixation, ipsilateral eye pain or headache, and the affected eyelid ptosis More commonly, an aneurysm can be diagnosed by DSA.

Head injury (20%):

Can affect the extraocular muscles and III, IV, VI on the cranial nerve and cause various forms of eye tendon, extraocular muscle contusion, orbital fracture, apical fracture, etc. can cause multiple extraocular tendons, internal carotid artery sponge Sinus can cause pulsating ocular protrusion and extraocular tendon, fractures of the bed and humerus, especially invading the abductor nerve. When the intracranial hematoma causes abdomen, ipsilateral oculomotor paralysis and contralateral hemiplegia occur. Intraocular tendons can sometimes be caused by an injury to the eyeball or ciliary ganglion.

Infection (30%):

1. Cavernous sinus syndrome: caused by cavernous sinus thrombosis or thrombotic cavernous sinusitis, often secondary to head and face carbuncles or sepsis, eyeballs protruding and fixed, pupil dilated, conjunctival and orbital congestion and edema; There may be papilledema, loss of vision or even complete blindness. If the cavernous sinus thrombus obstruction is re-communicated or the collateral circulation is established, the eyeball protrusion can be significantly relieved. One side of the cavernous sinus thrombus can also spread to the contralateral sponge through the sinusoid within a few days. Symptoms on both sides of the sinus, inflammation in the cavernous sinus can also spread to nearby tissues causing meningitis, brain abscess and so on.

2. supracondylar syndrome and apex syndrome: supracondylar syndrome showed III, IV, VI, V1 cranial nerve dysfunction, but no local inflammatory manifestations; such as Tolosa-Hunt with eyelid pain Syndrome, both visually impaired, called apex syndrome, can be caused by local chronic infection.

3. Others: Inflammation of the eye, the trochlear and the abductor nerve can also cause paralysis of these nerves. When otitis media or chronic mastoiditis develops to destroy the tip of the rock into the skull, it causes the V and VI of the affected side to cranial nerve function. Obstruction, known as rock bone tip syndrome or Gradenigo syndrome, various skull base meningitis, encephalitis can occur eye muscle dyskinesia.

Myasthenia gravis (10%):

It is a common cause of eye muscle spasm. Extraocular muscles are easily fatigued. Symptoms can be aggravated by continuous exercise. After rest, the symptoms are lightest. In the morning, the symptoms are the lightest, and the symptoms worsen every afternoon or evening.

Tumor stem tumor (5 % ):

Is a common cause of III, IV, VI cranial nerve palsy, sphenoid ridge meningioma, parasagittal meningioma, etc. can directly oppress the motor nerve of the eye, the abductor nerve is long in the intracranial stroke, intracranial hypertension, very easy It is compressed or pulled to produce abductor nerve paralysis. Nasopharyngeal carcinoma can directly invade into the skull from the holes in the skull base and cause eye muscle spasm.

Other (2 % ):

Cerebral arteriosclerotic vascular disease can often occur due to vascular occlusion, compression or bleeding, eye muscle spasm, diabetes can be caused by diabetic ischemic lesions and eye muscle spasm, a small number of migraine patients in the migraine attack or ipsilateral onset Uneven pupil dilation and extraocular tendon, ocular muscular dystrophy is a rare hereditary disease, and finally all extraocular muscle spasms can occur. Congenital eyelid ptosis and intraocular lens pseudotumor can occur. Eye muscle spasm caused by Wernicke encephalopathy is caused by a lack of vitamin B1. Hyperthyroidism or loss of pituitary function can also cause eye muscle spasm and eyeball protrusion.

Eye movement, trochlear and abduction neurological disease prevention

There are no special and effective preventive measures for this disease. Early detection and early treatment are the key to the prevention and treatment of this disease.

Eye movement, trochlear and abduction neurological complications Complications

Eye movement, trochlear and abductor nerve combined with complete paralysis, complete ocular muscle spasm, eyeball fixed in the median position, no movement in all directions, pupil dilated, light and regulation response disappeared.

Paralysis of the two eyes in the same vertical vertical motion (Parinaud syndrome) is caused by lesions in the midbrain of the midbrain, often with pupil dilation and disappearance of photoreaction, and a small number of patients are paralyzed in the same vertical motion.

Eye movement, trochlear and abduction neurological symptoms common symptoms supraorbital fissure syndrome paralysis eye muscle spasm palsy cranial nerve damage to light reaction disappearing ptosis

All age groups can be affected, the onset of disease is directly related to the cause of the disease, most of the aneurysms or vascular or inflammatory causes are rapid, the onset of cancer is slow and gradually develop, the disease can be divided into peripheral types, There are three types of karyotype and nuclear type.

(1) Peripheral eye movement nerve paralysis: cavernous sinus syndrome, supracondylar fissure syndrome and sacral apex syndrome have these three pairs of cranial nerve damage, the common feature is that the eye movements are limited or unable to move, the pupil dilated, At the same time, there is a cavernous sinus or supracondylar fissure syndrome in the affected area of the V-to-I-distribution area. The visual acuity is accompanied by the sacral cusp syndrome, and the passive movement or compression of the eye can be painful.

When the oculomotor nerve is completely paralyzed, the sacral ptosis occurs, the eyeball is slanted outward, the pupil is enlarged, the light response and the regulation reaction disappear, and the affected eye cannot move upward, downward or inward, but can still move slightly downward and downward, Due to the regulation of the lens due to the ciliary muscle spasm, the myopia is blurred, and the abducens nerve paralysis is mainly characterized by sudden or slow eyeball abduction movement limited or impossible.

(B) karyotypic karyotypic ocular tendon is characterized by: 1 oculomotor and trochlear nucleus paralysis are mostly bilateral, but often asymmetrical, more than 2 combined with adjacent tissue damage, such as oculomotor nucleus Most of the damage is combined with the damage of the medial longitudinal bundle, and there are intraocular and external tendon and the dyskinesia of both eyes. When the abductor nucleus is damaged, the affected side is often combined with the trigeminal nerve palsy, two eyes. The co-directional dyskinesia, 3 selectively damages only part of the function of the eye muscles, resulting in so-called isolated eye muscle spasm, 4 can appear bilateral pupils to disappear the photoreaction, while the regulatory response still exists, 5 often combined with long bundles (cones) Body bundles, feeling bundles) signs of damage.

(3) When the supra-nuclear lesions of the supra-nuclear eye muscles produce two-eye joint movement disorder, the eyes cannot cooperate with each other, and turn downwards or to one side, which is called gaze paralysis. The most common ones have two eyes with the same level of gaze. There are two types of paralysis in the same direction as the two eyes.

Eye movement, trochlear and abduction nerve disease examination

Eye movement, trochlear and abduction nerve disease examination items: ophthalmologic examination, nervous system examination, brain CT examination, brain MRI examination. Mainly for eye examination, brain CT excludes intracranial organic lesions.

Diagnostic identification of oculomotor, trochlear and abducens neuropathy

Oculomotor nerves, trochlear nerves, abductor nerve injuries and individual oculomotor nerve palsy and abductor nerves caused by various causes, as well as the identification of trochlear nerve palsy.

First, oculomotor nerve paralysis

(1) Nuclear and bundled paralysis

Because the oculomotor nucleus occupies a large range in the midbrain, nuclear damage often causes incomplete paralysis, and mostly bilateral, visible neurosyphilis, sausage poisoning and diphtheria. Bundle lesions cause paralysis of one side of the oculomotor nerve, which manifests as ipsilateral pupil dilation, loss of regulation and sag, and the eyeball is pulled outward by the lateral rectus muscle and superior oblique muscle and slightly downward.

1. Tumors of the brain stem: The clinical manifestation of the feature is the occurrence of cross palsy, ie, the ipsilateral nucleus and subnuclear cranial nerve lesions of the diseased segment and the contralateral pyramidal tract sign below the segment. Cranial nerve symptoms vary depending on the level and extent of the lesion. For example, the midbrain lesions are mostly manifested as lateral oculomotor nerve palsy, and the pons brain lesions can be manifested as lesion side abduction and facial nerve paralysis, the same lateral sensory disturbance and hearing impairment. The medullary lesions may have paraplegic lingual paralysis, paralysis of the throat, and loss of 1/3 of the taste of the tongue. Brain stem evoked potential, CT, MRI can be clearly diagnosed.

2. Injury of the brain stem: There is a clear history of trauma, long-term coma after injury, and eye movement disorders, etc., diagnosis is not difficult.

3. fracture of the base of the skull: after the traumatic brain injury can damage the internal carotid artery, resulting in internal carotid artery - cavernous sinus, eye movement limitation and vision loss, while having a head or ankle Continuous murmur, pulsatile eyeballs.

(2) Peripheral paralysis

1. Aneurysm of the base of the skull: When the oculomotor palsy appears alone, it is common in skull base aneurysms and rare in other tumors. The disease is more common in young adults, and has a history of chronic headache and subarachnoid hemorrhage. It can also occur as a separate oculomotor nerve palsy. Cerebral angiography can more clearly diagnose.

2. intracranial space occupying lesions: increased intracranial pressure in the brain injury and late brain tumors, generally indicating that cerebellar incision has occurred. The manifestation is that the pupil of the diseased side expands and the photoreaction disappears, and the contralateral limb can be paralyzed, followed by the expansion of the contralateral pupil, accompanied by disturbance of consciousness. According to the medical history and CT scan of the head, it is possible to confirm the diagnosis.

3. Cavernous sinus thrombosis and sinus aneurysm (carernous sinas thoomlosis and inter cavernous sinas aneurysm): can be expressed as cavernous sinus syndrome, in addition to oculomotor nerve spasm, there is the first damage of the trigeminal nerve, soft tissue inside the sputum, Upper and lower eyelids, bulbar conjunctiva, frontal scalp and nasal root congestion and edema, eyeball protrusion or papilledema, inflammation caused by systemic infection symptoms, combined with sacral X-ray film and lumbar puncture and blood routine examination can confirm the diagnosis.

4. Sacral fissure and apex syndrome: The former has oculomotor, trochlear, abductor nerve and the first dysfunction of the trigeminal nerve. The latter, in addition to the 3 pairs of cranial nerve damage, often accompanied by visual impairment, combined with ankle X-ray film of the optic nerve hole, blood test, CT of the ankle can be clearly diagnosed.

5. cephalitis meningitis: The oculomotor damage caused by meningitis is mostly bilateral, and is often involved in both the trochle and the abductor nerve. Cerebrospinal fluid examination showed an increase in the number of cells and protein.

Second, the trochlear nerve paralysis pulley nerve paralysis rarely appears alone, and more than the other two pairs of cranial nerves are involved at the same time. When the pulley nerve is paralyzed, it is not easy to identify if it is not double-checked. For differential diagnosis, see oculomotor paralysis.

Third, abduction nerve paralysis

(1) pontine haemonhage and tumour (pontine haemonhage and tumour): due to the close relationship with the facial nerve in the pons, the two nerves of the nuclear or vaginal paralysis often exist simultaneously, manifested as disease side abduction and facial nerve paralysis And contralateral hemiplegia, known as the Millard-Gubler's syndrome. The onset is often sudden and rapid coma, and the double pupils change like a needle. According to the clinical manifestations combined with CT, MRI examination is not difficult to establish.

(2) Radenigo's syndrome: localized inflammation of the apex of the otoderm of acute otitis media and meningioma of the vertebral bone can cause abductor nerve paralysis, accompanied by hearing loss and pain in the area of the trigeminal nerve. Gradenigo's sign group; X-ray film can be found here bone destruction or inflammatory changes. A diagnosis can be established by combining medical history with CT examination.

(3) Nasopharyngeal carcinoma: The reason why abductor nerve is invaded in the front of the skull base is most common in nasopharyngeal carcinoma, followed by cavernous sinus aneurysm and supraorbital fissure tumor. When a middle-aged patient presents with a single abductor nerve palsy or other manifestations of the cavernous sinus group, the presence of nasopharyngeal carcinoma should be considered first. Often accompanied by nasal discharge, nasal congestion, cervical lymphadenopathy, nasopharyngeal examination, biopsy, skull base X-ray examination can be diagnosed.

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