Presentation
fever, tremor
Patient Data
Diffuse leptomeningeal enhancement is seen on post-contrast FLAIR images (obtained after a 10-minute delay).
No clear sign of restricted diffusion.
No clear intra-axial T2 hyperintensity.
Leptomeningeal enhancement has resolved.
The signal of an enhancing cortical vein around the left parietal lobe hasn't been attenuated, appearing as a T2 hyperintensity on post-contrast FLAIR images (artifact).
Case Discussion
After CSF analysis, clinicians favored the diagnosis of viral meningitis and the patient received empirical antiviral therapy. Two weeks followup was negative for leptomeningeal enhancement.
The sensitivity of contrast enhanced FLAIR sequences is remarkably higher in comparison to contrast enhanced T1-weighted sequences for the imaging diagnosis of meningitis. The main reason is the better distinction between enhancing meninges and enhancing cortical veins. The signal of contrast enhanced cortical veins is attenuated only on FLAIR images. 1