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Difficulty: HardNeurosurgery

Brain herniation syndromes occur when elevated intracranial pressure forces brain parenchyma across rigid intracranial structures. Based on the clinical features provided, match each clinical presentation to its corresponding specific brain herniation syndrome.

  • New-onset contralateral lower extremity weakness and abulia in a patient with a rapidly expanding frontal lobe mass, with preserved pupillary reflexes.Subfalcine (cingulate) herniation
  • Ipsilateral fixed and dilated pupil with subsequent contralateral hemiparesis in a patient with a rapidly expanding temporal epidural hematoma.Uncal (transtentorial) herniation
  • Sudden-onset respiratory arrest, severe bradycardia, and flaccid quadriplegia in a patient with a massive cerebellar hemorrhage.Tonsillar (foramen magnum) herniation
  • Progressive, symmetric rostrocaudal neurological deterioration with Cheyne-Stokes respirations and bilateral small but reactive pupils in a patient with diffuse cerebral edema.Central (downward transtentorial) herniation
  • Rapidly worsening obstructive hydrocephalus and impaired upward conjugate gaze (Parinaud syndrome) in a patient with an enlarging posterior fossa tumor.Upward cerebellar herniation

Answer

The correct matches are: 1 (Contralateral leg weakness) with Subfalcine herniation; 2 (Fixed pupil and hemiparesis) with Uncal herniation; 3 (Respiratory arrest) with Tonsillar herniation; 4 (Symmetric rostrocaudal deterioration) with Central herniation; and 5 (Parinaud syndrome) with Upward cerebellar herniation.
Each herniation syndrome compresses specific, predictable neurovascular structures. Subfalcine herniation traps the anterior cerebral artery, causing contralateral leg weakness. Uncal herniation compresses CN III and the midbrain, leading to an ipsilateral blown pupil and contralateral hemiparesis. Tonsillar herniation compresses the medulla, causing respiratory arrest. Central herniation causes symmetric diencephalic compression (Cheyne-Stokes breathing). Upward cerebellar herniation compresses the dorsal midbrain, causing vertical gaze palsy (Parinaud syndrome).

Step-by-Step Solution

1
Analyze the first clinical presentation: contralateral leg weakness with intact pupils.
Identified as anterior cerebral artery (ACA) compression.
Subfalcine herniation shifts the cingulate gyrus beneath the falx cerebri, trapping the ACA without directly compressing the brainstem.
2
Analyze the second presentation: ipsilateral dilated pupil and contralateral hemiparesis.
Identified as Cranial Nerve III and cerebral peduncle compression.
Uncal herniation pushes the medial temporal lobe over the tentorial edge, compressing adjacent midbrain structures.
3
Analyze the third presentation: sudden respiratory arrest and flaccid quadriplegia.
Identified as profound medullary compression.
Tonsillar herniation forces the cerebellar tonsils through the foramen magnum, compromising the vital cardiorespiratory centers in the medulla.
4
Analyze the fourth presentation: symmetric rostrocaudal decline with Cheyne-Stokes respirations.
Identified as generalized downward pressure on the diencephalon.
Central herniation involves the symmetric downward displacement of deep central brain structures through the tentorial incisura.
5
Analyze the fifth presentation: Parinaud syndrome (upward gaze palsy) and obstructive hydrocephalus.
Identified as tectal plate compression from below.
Upward cerebellar herniation occurs when a posterior fossa mass forces the cerebellum upward through the tentorial notch, compressing the dorsal midbrain.

Key Concept

Clinical localization and neurovascular consequences of distinct brain herniation syndromes
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Topics

Neurosurgery

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