Learning objectives
- Learning
- Understand
- Integrate
- Reflect
|
Note that anatomical pictures of the pons are upside down compared with the CT/MRI except below
Introduction
- Usually lacunar type infarcts
- Age, hypertension, diabetes, atherosclerosis
Aetiology
- Pontine strokes are usually unilateral and reflect small vessel occlusion of penetrating vessels.
- Occasionally a basilar artery occlusion blocking the ostia can result in bilateral infarction
- Small vessel strokes share same risk factors as small vessel disease elsewhere with hypertension, diabetes and age as significant risk factors.
- Large vessel basilar infarcts also share the same risk as other large vessel strokes including localised atherosclerosis and embolism.
- The fact that the fourth ventricle lies behind the pons means that any swelling here can result in obstructive hydrocephalus which may require shunting.
Clinical
- Contralateral weakness and sensory symptoms
- No cortical signs or hemianopia
- Ipsilateral Facial palsy
- Diplopia, Lateral gaze palsy if VIth nerve affected
- Comatose, locked in syndrome with preservation of upward gaze, Pinpoint pupils
- Pyrexias and autonomic dysfunction
- LMN or UMN VIIth which is ipsilateral.
- Variants of Quadriparesis due to corticospinal involvement
- There may be waxing and waning of symptoms initially like a capsular warning syndrome
- Sensory symptoms
- Dysarthria - Clumsy hand type Lacunar syndromes
- Vertigo, Dizziness due to involvement of cerebellar peduncles
Infarcts almost always respect the midline and can extend to cerebellum
Investigations
- FBC, U&E, LFTs, Glucose, lipids
- CT/CTA as needed
- MRI may show the infarct
- Consider MRA to look for vascular stenosis
Management
- Reperfusion therapies where indicated - reperfusion of an MCA may increase flow to the lenticulostriate artery.
- Admission to stroke unit
- Aspirin 300 mg +/- Clopidogrel
- Optimise BP control if hypertension and glucose control if diabetic
- Statin to lower Cholesterol