What is the treatment for upward herniation?

Treatment of Upward Herniation

Upward transtentorial herniation requires immediate emergency ventriculostomy (external ventricular drain) as first-line treatment, followed by decompressive suboccipital craniectomy if CSF drainage fails to improve neurological function. 1

Immediate Surgical Management Algorithm

First-Line: Emergency Ventriculostomy

• Emergency external ventricular drain (EVD) placement is the initial surgical intervention for upward herniation with obstructive hydrocephalus 1
• Ventriculostomy effectively relieves symptoms in many cases by draining cerebrospinal fluid and reducing intracranial pressure 1
• Critical caveat: Risk of upward herniation can paradoxically worsen with ventriculostomy alone if excessive supratentorial CSF is drained too rapidly 1, 2
• Use conservative CSF drainage to minimize this risk—drain slowly and monitor neurological status continuously 1

Second-Line: Decompressive Suboccipital Craniectomy

• If ventriculostomy fails to improve neurological function, proceed immediately to decompressive suboccipital craniectomy 1
• This involves suboccipital craniectomy with durotomy and duraplasty to reduce brainstem compression and restore CSF drainage 1
• Indicated when cerebellar infarction or posterior fossa mass causes neurological deterioration despite maximal medical therapy 1
• 85% of patients progressing to coma die without surgical intervention, but half of those treated with decompression achieve good outcomes 1

Combined Approach When Indicated

• When safe and appropriate, treat obstructive hydrocephalus concurrently with ventriculostomy during decompressive surgery 1
• This combined approach addresses both the mass effect and CSF drainage simultaneously 1

Medical Management (Temporizing Only)

While awaiting definitive surgical treatment:

• Elevate head of bed, administer osmotic diuretics (mannitol), and consider hyperventilation 1
• These measures provide only transient benefit and should not delay surgical intervention 1
• Aggressive medical reversal using hyperventilation, mannitol, and hypertonic saline can temporarily reverse transtentorial herniation and preserve neurological function if applied early 3

Critical Clinical Recognition

Signs of Upward Herniation

• Coma with reactive miotic pupils, asymmetrical or absent caloric responses, and decerebrate posture indicate brainstem compression 4
• Development of unequal, then midposition fixed pupils signals midbrain failure from upward herniation 4
• Vertebral angiography shows upward displacement of superior cerebellar arteries 4

Common Precipitating Causes

• Cerebellar hemorrhage or tumor 4
• Hemorrhagic cerebellar infarction 4, 5
• Excessive supratentorial CSF drainage (iatrogenic cause during ventriculostomy or other procedures) 2
• Large posterior fossa mass lesions 4

Transfer and Monitoring

• Rapidly transfer patients to a center with neurosurgical expertise if condition is deemed survivable 1
• Perform serial physical examinations and neuroimaging to identify worsening brain swelling 1
• Immediately intubate if neurological deterioration with respiratory insufficiency develops 1
• Patients require at least 48 hours of close neurological monitoring to stabilize intracranial pressure 1

Prognostic Counseling

• Although mortality after transtentorial herniation is high (60% in-hospital mortality), meaningful recovery is possible with aggressive intervention 3
• When considering decompressive suboccipital craniectomy, inform families that good outcomes are achievable after the procedure 1
• Second episode of herniation and midbrain involvement during herniation are associated with higher in-hospital mortality 3
• Among survivors of aggressive treatment, 64% achieved functional independence (Rankin score <3) at long-term follow-up 3

Alternative Approaches in Specialized Centers

• In centers with neuro-endoscopic expertise, endoscopic third ventriculostomy (ETV) is preferred for certain cases of obstructive hydrocephalus 1
• Hyperbaric oxygen treatment (HBOT) has been reported as adjuvant therapy in isolated cases of acute brain herniation, though this remains experimental 6