HBrainstem Anatomy (NEET PG Focus)
Key Cross-Sectional Landmarks
| Level | Key Landmarks/Nuclei |
|---|---|
| Midbrain | Superior/Inferior Colliculi, Red Nucleus, Substantia Nigra, Cerebral Peduncles (CN III exits). |
| Pons | Basilar Pons, Middle Cerebellar Peduncle, CN V, VI, VII, VIII nuclei. |
| Medulla | Pyramids (decussation), Inferior Olivary Nucleus, CN IX, X, XI, XII nuclei. |
NEET PG “Must-Know” Pearls
- Rule of 4s:
- 4 nerves in Medulla (9-12), 4 in Pons (5-8), 4 above (1-4).
- Midline structures start with “M” (Motor pathway, Medial Lemniscus, MLF, Motor cranial nerve nuclei).
- Side structures start with “S” (Spinocerebellar, Spinothalamic, Sensory nuclei of CN V, Sympathetic pathway).
- Wallenberg Syndrome (Lateral Medullary): PICA occlusion. Features: Contralateral loss of pain/temp (spinothalamic), ipsilateral loss of pain/temp (CN V), ataxia, Horner’s syndrome, dysphagia/hoarseness (nucleus ambiguus).
- Medial Medullary Syndrome: ASA occlusion. Features: Contralateral hemiparesis, contralateral loss of vibration/proprioception, ipsilateral tongue deviation (CN XII).
For additional high-yield questions and medical resources, you may visit mymedschool.org.