DX: Acute pontine-mesencephalic infarct

Patient needed to be examined thoroughly by a neurologist because a lesion in this region could have multiple clinical manifestations. First of all, MR gave us a big hint on the nature of the disease: acute infarct. Now where exactly is the lesion? is it pontine or mesencephalic?.. the importance of this is because the origin of some cranial nerves.

Here is the depictive MR:

Maybe it is a borderline lesion between pontine and mesencephalic altough with more extension to cephalic portion of pons.

Good neurological examination could have given us a hint.

Cranio-facial autonomic symptoms such as ipsilateral lachrymation, rhinorrhoea, conjuctival congestion, ptosis, or eyelid oedema are the sine qua non of trigeminal autonomic cephalalgia. It is thought that activation of the trigeminal afferent system generates pain, and co-activation of the VIIth nerve efferent parasympathetic pathway produces the autonomic manifestations such as ipsilateral lachrymation and rhinorrhoea.

Ischaemia in the ponto-mesencephalic junction could involve the trigeminal main sensory and mesencephalic nuclei, resulting in facial dysaesthesia comparable to ischaemic nerve pain. In contrast to the “boring” intense pain often encountered with trigeminal autonomic cephalalgias, the burning dysaesthesias are more consistent with ischaemia. Ischaemia could also trigger trigemino-facial synapses in the superior salivatory nucleus and switch on the facial efferent parasympathetic pathway, resulting in ipsilateral lachrymation and rhinorrhoea.

In this case hemiparesia and hemiplegia were the main symptoms so Millard-Gubler and Raymond-Foville are to consider although the location is usually in medulla or base of the pons.

Named Brainstem Syndromes

Eponym	Site	Cranial Nerves	Tracts	Signs	Usual Cause
Weber	Base of Midbrain	III	Corticospinal	Oculomotor palsy with crossed hemiplegia	Vascular, tumor
Claude	Midbrain tegmentum	III	Red nucleus and Brachium Conjunctivum	Oculomotor palsy with contralateral cerebellar ataxia and tremor	Vascular, tumor
Benedict	Midbrain tegmentum	III	Red nucleus, corticospinal tract, brachium conjunctivum	Oculomotor palsy, contralateral cerebellar ataxia, corticospinal signs	Vascular, tuberculoma, tumor
Nothnagel	Midbrain tectum	Unilateral or bilateral III	Superior cerebellar peduncles	Ocular palsies, paralysis of gaze, cerebellar ataxia	Tumor
Parinaud	Dorsal Midbrain			Paralysis of upward gaze and accommodation, fixed pupils, retraction nystagmus	Pinealoma, hydrocephalus
Millard-Gubler and Raymond-Foville	Base of Pons	VII and sometimes VI	Corticospinal tract	Facial and 6th palsy, contralateral hemiplegia, sometimes gaze palsy	Vascular,tumor
Avellis	Medulla tegmentum	X	Spinothalamic, sometimes pupillary fibers	Paralysis of soft palate and vocal cord and contralateral hemianesthesia	Infarct or Tumor
Jackson	Medulla Tegmentum	X,XII	Corticospinal	Avellis plus ipsilateral tongue	Infarct or Tumor
Wallenberg	Medulla, lateral tegmentum	Spinal V,IV,X,XI	Lateral STT,Descending Pupil fibers, Spinocerebellar and olivocerebellar tracts	Ipsi V, IV, X, XI palsy, Horner's, cerebellar ataxia. Contra pain and temp	Vascular - Pica or vertebral

 http://www.dizziness-and-balance.com/disorders/central/strokes/brainstem%20strokes.htm


 Check out this articles also:

http://jnnp.bmj.com/content/76/7/1041.1.full
http://en.wikipedia.org/wiki/Lateral_pontine_syndrome
http://www.strokecenter.org/professionals/stroke-diagnosis/stroke-syndromes/inferior-medial-pontine-syndrome-foville-syndrome/
http://www.strokecenter.org/professionals/stroke-diagnosis/stroke-syndromes/ventral-pontine-syndrome-millard-gubler-syndrome/
http://stroke.ahajournals.org/content/28/3/649.full


Hope it was helpful, until next time!