Q 1.22. Brainstem Vascular Syndromes: Medulla Oblongata

1. Lateral Medullary Syndrome (Wallenberg Syndrome):

   • Affected Artery: Posterior Inferior Cerebellar Artery (PICA) or its branches.
   • Clinical Manifestations:
     • Body Representation:
       • Contralateral loss of pain and temperature sensation in the arm and leg (via the spinothalamic tract).
       • Ipsilateral ataxia in the arm and leg (via the spinocerebellar tract).
       • Ipsilateral loss of pain and temperature sensation in the face (sensory nucleus of trigeminal nerve).
     • Other Features:
       • Horner’s syndrome (ipsilateral eye ptosis, anhidrosis, and miosis).
       • Vertigo, nystagmus (vestibular nucleus).
       • Loss of gag reflex (vagus nerve).
       • Dysphagia (nucleus ambiguus and glossopharyngeal nerves).

2. Medial Medullary Syndrome (Dejerine Syndrome):

   • Affected Artery: Anterior Spinal Artery or its branches.
   • Clinical Manifestations:
     • Body Representation:
       • Contralateral weakness in the arm and leg (corticospinal tract).
       • Contralateral loss of vibration and proprioception (medial lemniscus).
     • Other Features:
       • Internuclear ophthalmoplegia (ipsilateral eye deviation during attempted lateral gaze).
       • Deviation of the tongue toward the side of the lesion (hypoglossal nerve).

These syndromes result from vascular occlusion or mass effect within the brainstem.

References:

(1)researchgate.net

(2)pubs.rsna.org

(3)pubmed.ncbi.nlm.nih.gov