Senin, 17 Maret 2014

Paralysis of the 6th cranial nerve (abducens nerve)



Many disorders can cause paralysis , such as :

Head Injury
* tumors
* Multiple sclerosis
* Aneurysms
* Infections of the brain , such as meningitis , brain abscess or parasitic infections
* Complications of ear or eye infections
* Blockage of the arteries that supply the nerve , can be caused from diabetes , stroke , transient ischemic attack , or vasculitis .
* Wernickle 's encephalopathy ( commonly caused by chronic alcohol )
* Benign intracranial hypertension ( pseudotumor cerebri )
* Respiratory infections ( in children )

Some disruption is putting pressure on the nerve causes swelling around or increased pressure within the skull . The other relates to the flow of blood to the nerve .

If this paralysis occurs alone ( without other cranial nerve palsy ) , the cause is often never identified .

SYMPTOMS

Affected eye as a whole can not be flipped outwards and could turn into when people look straight ahead . Double vision occurs when people look forward to the side of affected eye . Other symptoms depend on the cause . They include severe headaches , fluid retention ( edema ) in the conjunctiva , numbness of the face and mouth , loss of vision , and inability to move the eyes in other orders .

Diagnosis

Usually , doctors can easily recognize the 6th nerve paralysis , but the cause is less obvious . Ophthalmoscope is used to look inside the eye and check for the presence of tumor , increased pressure , and abnormalities in the blood vessels . CT or , recommended , MRI was done to negate the possibility of tumors and other abnormalities . If the results are not clear , spinal injections ( lumbar puncture ) is done to ascertain whether the pressure inside the skull increases and whether the tumor or swelling caused by an infection or exposure to the nerve . If the symptoms of vasculitis is suspected , blood removed to check for signs of inflammation , such as abnormalities of certain antibodies ( antinuclear antibodies and rheumatoid factor ) and abnormalities in the blood levels of erythrocyte sedimentation ( ESR - how quickly red blood cells fall to the bottom of a test tube containing blood ) . Once all the tests conducted , the cause may remain unknown .

TREATMENT

Treatment depends on the cause . When the cause is treated , the paralysis usually solved . Paralysis with no identifiable cause is usually resolved without treatment within 2 months , as occurred in those caused by blockage of blood vessels .