Caption: Figure 1: Contrast-enhanced cranial CT demonstrating a hemorrhagic focus in the right parietal and occipital lobes with possible secondary bilateral infarction due to compression of posterior circulation vessels, subfalcine herniation, beginning uncal herniation
, and cerebral edema.
Emergent computed tomography (CT) of the head revealed a ventricular colloid cyst with hydrocephalus and uncal herniation
as shown in Figures 1 and 2.
Brain computed tomography revealed the left frontotemporoparietal acute SDH with uncal herniation
In our cohort, patients with uncal herniation
were four times more likely to have poor outcome and poor outcome was 2.5 times more likely if there was subfalcine herniation [septum pellucidum deviation more than 1cm] (Table 2).
Patients presenting with low GCS and anisocoria and computed tomography (CT) image showing significant lesions with evidence of uncal herniation
[Figure 1] were immediately taken up for surgical evacuation [Figure 2].
Because of features of uncal herniation
, an emergency craniotomy was performed immediately.
An autopsy revealed cerebral edema with uncal herniation
, pulmonary edema, bronchopneumonia of the right lung, and hepatic congestion.
. Displacement of the temporal lobe or hippocampus causes compression of the third cranial nerve, causing sluggish and then fixed dilated pupils (initially on the same side as the herniation--'blown pupil').
A unilateral dilated pupil suggests the presence of a structural lesion with uncal herniation
. Pontine lesions result in pinpoint pupils, while midbrain lesions are associated with midposition fixed pupils.
Massive brain swelling is far more common in patients with the lowest pre-operative GCS scores and those with unilateral or bilateral dilated pupils, suggesting a relationship to prior hypoperfusion.33 Most are associated with early death due to increased ICP and subsequent uncal herniation
.32 Our patients with herniation both had a lower survival rate and unfavourable outcome.
However, the patient exhibited no other signs of increased intracranial pressure or uncal herniation
and had no decline in mental status.
Examination of the brain showed obstructive hydrocephalus, bilateral uncal herniation
, flattening of the cerebral gyri, and an intact cysticercus compressing the inferior 4th ventricle (Figure 1).
Possibilities included uncal herniation
and seizure due to infiltration of the cerebral cortex by the tumor.
In spite of normal ICP values, imaging may reveal a contralateral hemorrhage with mass effect and even uncal herniation