09 Brainstem

Overview

Sections

• top: midbrain

• right: pons

• lower: medulla

Midbrain

• MLF: medial longitudinal fascicules: lesion causes lateral gaze (internuclear ophthalmoplegia)

• red nucleus: fine tuning fine movements

• coordinate upward gaze

Pons

• vestibular: nausea, vomiting, vertigo, nyastagmus

• V: pain and sensation in face

• PPRF, MLF, CN 6 all needed for lateral gaze

Medial Pontine Syndrome

Lateral Pontine Syndrome

Medulla

• hypothalamospinal: sympathetic nerves

Medial Medullary Syndrome

Lateral Medullary Syndrome

Rule of 4's

• 4 CN's in medulla, 4 in pons, 4 above pons

• big cranial nerve, stretches from pons to medulla

• CN 8: only use hearing loss to localize to pons, not vestibular signs

Cases