Neu 9 - Brainstem Lesion

Question 1

What causes and what are the symptoms of Weber syndrome?

Answer 1

Midbrain infarction resulting from occlusion of the paramedian branches of the posterior cerebral artery: Cerebral peduncle lesion results in Contralateral spastic paralysis (AKA Contralateral hemiparesis). Oculomotor nerve (CN III) palsy results in Ipsilateral ptosis, pupillary dilation, and lateral strabismus (eye looks down and out).

Question 2

Which possible causes results in Locked-in syndrome?

Answer 2

Lesion in superior pons, Basilar artery strokes, hyponatremia corrected too quickly, leading to central pontine myelinolysis.

Question 3

Patient whose hyponatremia was corrected too quick and develops quadriplegia, what is the name of this syndrome?

Answer 3

Locked-in syndrome

Question 4

Which are the symptoms of the locked syndrome?

Answer 4

Preserved consciousness and blinking, quadriplegia, loss of voluntary facial, mouth, and tongue movements.

Question 5

What is the cause of medial inferior pontine syndrome?

Answer 5

Caused by occlusion of a paramedian branch of the basilar artery resulting in unilateral infarct of medial aspect of inferior pons.

Question 6

What are the symptoms of medial inferior pontine syndrome?

Answer 6

Contralateral spastic hemiparesis, Contralateral loss of light touch/vibratory/kin esthetic sensation, Paralysis of gaze to side of lesion, Ipsilateral paralysis of lateral rectus muscle, Note that pain and temperature sensation are persevered.

Question 7

Damage to which areas causes medial inferior pontine syndrome symptoms?

Answer 7

1)Contralateral spastic hemiparesis (corticospinal tract damaged). 2)Contralateral loss of light touch/vibratory/skin esthetic sensation (medial Lemniscus damage). 3)Paralysis of gaze to side of lesion (damage to pontine gaze center: PPRF and abductees nucleus). 4)Ipsilateral paralysis of lateral rectus muscle (damage to abducens nerve fiber). Note that pain and temperature sensation are persevered.

Question 8

What are the symptoms of lateral inferior pontine syndrome?

Answer 8

1)Ipsilateral facial nerve paralysis. 2)Ipsilateral loss of taste from anterior 2/3 of tongue. 3)Nystagmus, vertigo, nausea/vomiting. 4)Ipsilateral limb and gait ataxia. 5)Ipsilateral loss of pain and temperature sensation from the face. 6)Ipsilateral Horner syndrome.

Question 9

What is the cause of lateral inferior pontine syndrome?

Answer 9

Caused by occlusion of one of the anterior inferior cerebellar artery (AICA) resulting in unilateral infarct of lateral aspect of inferior pons (AKA anterior inferior cerebellar artery syndrome).