Home » Anatomy » Gross Anatomy » Case of Lesion in the Brain Stem

Case of Lesion in the Brain Stem

A 64 year old professor complains of weakness in his right arm and leg[1] and double vision[2]. He also said that he was having weakness in the lower half of his face on the right side[3]. Neurologic examination revealed a dilated pupil which was fixed to light and ptosis on the left side[4]. Babinski sign was present on the right side[6]. There was some weakness but no atrophy of the muscles of the face on the right side. There was evidence of spastic paralysis of the right arm and leg[7]. There was no sensory loss on either side of the head, trunk or limbs. Lesion in the brain stem occurred characteristic of Weber syndrome.[5]


[5] Weber Syndrome:

Produced by occlusion of  a branch of posterior cerebral artery that supplies midbrain, resulting in necrosis of brain tissue, including the oculomotor nerve and the crus cerebri.

[1][3] Weber syndrome is characterized by the presence of ipsilateral opthalmoplegia and contralateral paralysis of the lower part of face, tongue and the arm and leg. Difficulty with contralateral lower facial muscles and hypoglossal functions is indicative of damage to the corticobulbar tract.

[4] The eyeball is deviated laterally because of the paralysis of medial rectus muscle.

Drooping of upper eyelid is also seen and the pupil is dilated and fixed to light and accomodation due to malfunction of the parasympathetic nucleus of the oculomotor nerve.


Diplopia or double vision is caused by problem in any of the following areas:

1) Cornea- infections e.g. herpes zooster

2) Lens- cataracts

3) Eye muscles- myasthenia gravis

4) Nerves- multiple sclerosis, uncontrolled diabetes

5) Brain- stroke, increased pressure, aneurysms, tumors

[6] Babinski Sign

Babinski sign is indicative of upper motor neuron lesion. contralateral hemiparesis and typical upper motor neruron lesion findings are indicative of damage to the corticospinal fibers.

[7] Spastic Paralysis:

Spastic paralysis is indicative of damage to the extrapyramidal system.


Lesion occured on the left side as is indicated by weakness of right arm and leg as well as weakness of lower half of face on right side.  Lesion included the corticospinal and corticobulbar tracts as well as the oculomotor nerve

Check Also

Axillary Artery

Axillay artery, a continuation of the subclavian artery, begins at the lateral border of the …

Leave a Reply

Your email address will not be published. Required fields are marked *