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Difficulty: HardNeurosurgery

Match each clinical presentation and underlying pathophysiological mechanism to the correct brain herniation syndrome.

  • A patient with a hemispheric mass develops contralateral leg-predominant weakness and abulia due to compression of the anterior cerebral artery.Subfalcine (cingulate) herniation
  • A trauma patient develops an ipsilateral fixed, dilated pupil and contralateral hemiparesis due to compression of the oculomotor nerve and cerebral peduncle.Uncal (transtentorial) herniation
  • A patient with a posterior fossa lesion suddenly develops flaccid quadriplegia and respiratory arrest secondary to medullary compression.Tonsillar (foramen magnum) herniation
  • A patient with diffuse cerebral edema exhibits progressive rostrocaudal decline, beginning with Cheyne-Stokes respirations and small reactive pupils due to diencephalic displacement.Central (transtentorial) herniation

Answer

1 matches with Subfalcine herniation, 2 matches with Uncal herniation, 3 matches with Tonsillar herniation, and 4 matches with Central herniation.
Each clinical scenario precisely maps to the anatomical structures compressed during specific brain herniation syndromes. Subfalcine herniation compresses the anterior cerebral artery. Uncal herniation compresses the oculomotor nerve and midbrain. Tonsillar herniation compresses the lower medulla. Central herniation symmetrically displaces the diencephalon and brainstem.

Step-by-Step Solution

1
Analyze the vascular and structural compression described in the first presentation.
Compression of the anterior cerebral artery causing leg-predominant weakness is the hallmark of subfalcine (cingulate) herniation.
The cingulate gyrus herniates under the rigid falx cerebri, trapping the pericallosal arteries.
2
Evaluate the cranial nerve and motor tract findings in the second presentation.
An ipsilateral fixed pupil and contralateral hemiparesis indicate uncal herniation.
The uncus of the temporal lobe herniates across the tentorial incisura, compressing the third cranial nerve and the cerebral peduncle.
3
Identify the brainstem level compromised in the third presentation.
Medullary compression causing respiratory arrest and flaccid quadriplegia is characteristic of tonsillar herniation.
The cerebellar tonsils herniate through the foramen magnum, directly impinging on the respiratory centers in the medulla oblongata.
4
Assess the pattern of neurological decline in the fourth presentation.
Progressive rostrocaudal decline points to central herniation.
Diffuse edema causes downward axial displacement of the diencephalon and midbrain through the tentorial notch.

Key Concept

Clinical correlation of brain herniation syndromes
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Topics

Neurosurgery

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