Jauss Score for Cerebellar Infarction
The Jauss score is a 10-point radiological scale that quantifies mass effect in the posterior cranial fossa after cerebellar infarction, with scores ≥3-4 points predicting malignant cerebellar edema requiring surgical intervention.
What the Jauss Score Measures
The Jauss scale assesses the degree of mass effect in the posterior fossa by evaluating specific radiological features on CT imaging 1. A threshold value of 3 points or more indicates significant risk for developing malignant cerebellar infarction 2. The scale reaches up to 10 points, with scores ≥4 consistently defined as malignant in the literature 3.
Key Radiological Components Assessed
The score incorporates the following critical imaging findings 1:
- Hypodensity involving >2/3 of the cerebellar hemisphere - the most important predictor of space-occupying edema
- Compression or displacement of the 4th ventricle - indicates brainstem compression
- Obstructive hydrocephalus - from fourth ventricle obstruction
- Displacement of the brainstem - direct mass effect
- Compression of the basal cisternae - sign of critical herniation risk
- Hemorrhagic transformation - worsens mass effect
Clinical Application and Risk Stratification
Patients with cerebellar infarct volume >20 cm³ AND Jauss score ≥3 points develop malignant course in 67% of cases 2. This combination provides the most reliable early prediction for surgical need.
When to Apply the Score
- Obtain baseline CT immediately in all patients with cerebellar infarction 1
- Calculate Jauss score on initial imaging to stratify risk 2
- Any patient with ≥1 risk factor for space-occupying edema requires immediate stroke unit evaluation by both neurologist and neurosurgeon 1
Critical Timing Considerations
Peak swelling typically occurs 3-5 days after onset, but 39.4% of malignant cases develop after 72 hours 4, 5. Therefore:
- Monitor all territorial cerebellar infarcts for up to 5 days, even if initially stable 1, 4
- Serial imaging is essential - initial CT can be normal in 25% of cases 4
- Infarct volume >38 cm³ carries >50% swelling risk 5
Integration with Clinical Predictors
The Jauss score should be interpreted alongside clinical warning signs 1, 4:
Most reliable clinical predictor:
- Progressive impairment of consciousness - the single most important clinical indicator of tissue swelling 1, 4, 6
Late signs of impending herniation (act immediately):
- Hypertension with bradycardia 1, 4
- Irregular breathing patterns 4
- Pupillary changes (anisocoria or pinpoint pupils) 4
- Loss of oculocephalic responses 4
Surgical Decision-Making
Surgical decompression (suboccipital craniectomy with dural expansion) is indicated when Jauss score ≥3-4 points with clinical deterioration 2, 3. The combination of decompressive craniectomy and external ventricular drainage is most effective, reducing mortality from occlusion/dislocation syndrome by 35.8% 2.
Additional Surgical Predictors Beyond Jauss Score
Recent evidence identifies early infarct-edema growth rate as the strongest independent predictor of surgical need (OR 2.55), even after adjusting for baseline volume 7. However, the Jauss score remains the established clinical tool for initial risk stratification 2.
Common Pitfalls to Avoid
- Do not rely on initial CT alone - 25% may appear normal initially 4
- Do not wait for late herniation signs (bradycardia, irregular breathing) - these appear immediately before respiratory arrest 1
- Do not perform ventriculostomy alone for hydrocephalus - must accompany with suboccipital decompression to avoid upward cerebellar herniation 1
- Do not discharge patients with Jauss score ≥3 before 5-day monitoring period 4, 5
Prognostic Factors After Surgery
When surgery becomes necessary, outcomes depend on 8:
- Higher premorbid mRS (OR 2.715) - worse outcome
- Higher admission NIHSS (OR 1.088 per point) - worse outcome
- Presence of brainstem infarction (OR 7.035) - significantly worse outcome
Despite these risks, 41.4% of surgically treated patients achieve good functional outcome (mRS 0-3) at 90 days, with 27.6% mortality 8.