Table 1 Imaging findings associated with CSH

CT-scan

Well-demarcated hyperdense lesion. May be occasionally dumbbell-shaped with sellar extension and/or dural tail

T1-weighted MRI

Low or isointense pre-contrast signal

T1 contrast enhanced MRI

Lobulated structure and homogeneous or progressive filling-in enhancement of the lesion from the periphery to center. Homogeneous filling-in may more likely be seen with subtype A

T2-weighted, fluid-attenuated inversion recovery (FLAIR) and proton-density MRI

Extra-axial hyperintense lesion. T2-weighted signal intensity similar to CSF signal

Apparent diffusion coefficient (ADC) map and diffusion-weighted MRI (DWI)

No restriction of diffusion normally seen in ADC map. Isointense to adjacent brain tissue in DWI

Magnetic resonance spectroscopy (MRS)

Small choline and N-acetyl-aspartate peaks without frank alanine peak. A large lipid peak could be seen at 0.9–1.3 ppm

Digital subtraction angiography (DSA)

Delayed tumoral blush irrigated by dural branches of the carotid siphon and middle meningeal artery. One-third of CSHs may be angiographically silent