It typically affects the base of skull, the vertebral bodies, and the sacrococcygeal bone, but may be rarely seen in the extraaxial
skeleton, such as intervertebral discs and presacral soft tissue.
The CT scan finding shows that 50% cases had intraaxial lesions and 40% had extraaxial
lesions, while 10% had both (Figure 1).
Arachnoid cysts are extraaxial
and displace the brain cortex from the adjacent skull .
These frequently arise in an intradural extraaxial
location anterior to the cervical-thoracic spinal cord while intracranial cysts have a tendency to be infratentorial.
Axial and sagittal T1WI (A and B) and axial and coronal T2WI (C and D) show a large extraaxial
lobulated smooth marginated high signal intensity pattern cystic lesion in the suprasellar region with its regional extension.
Brain abscess complications include local mass effect with intracranial herniation, hydrocephalus, meningitis, extra-axial fluid collection, sinus thrombosis, infarct, cranial nerve involvement, ventriculitis, and extraaxial
fluid collections (empyema and hygroma).
Imaging features of extraaxial
Intraaxial lesions enhance when blood-brain barrier breaks down, and extraaxial
lesions usually enhance due to high vascularity (8).
Foi realizada tomografia computadorizada que evidenciou a presenca de massa extraaxial
em cortex frontal direito de aproximadamente dois centimetros de diametro, com areas de calcificacao, efeito de massa, desvio da fissura longitudinal a direita, com realce apos aplicacao do meio de contraste (Figura 1).