Cerebral abscess

Case contribution: Dr Radhiana Hassan

Clinical:

  • A 42 years old man with underlying retroviral infection
  • Presented with headache and transient altered consciousness
  • Clinical examination was unremarkable
  • Blood investigations are normal
Non-contrast CT scan of the brain in axial plane

CT scan findings:

  • A small lesion is seen at the left basal ganglia (white arrow)
  • Itis asosciated with marked perilesional oedema
  • Minimal mass effect to the ipsilateral lateral ventricle
  • No midline shift. No hydrocephalus.
MRI brain in T1, T2, FLAIR and T1+gadolinium
MRI brain in axial DWI, ADC and Hemo sequences. Coronal T1 and Sagittal T1 images at lower row
MR spectroscopy shows lactate and lipid peaks

MRI findings:

  • There is a lesion at left basal ganglia which is hypointense on T1, hyperintense on T2 and shows ring enhancement on post contrast
  • It also shows restricted diffusion on DWI/ADC.
  • Marked perilesional oedema is seen.
  • Lactate and lipid peak are also seen on MRS

Diagnosis: Cerebral abscess.

Discussion:

  • Intracranial abscesses are uncommon, serious and  life-threatening infections.
  • Intracranial abscesses can originate from infection of contiguous structures, secondary to hematogenous spread from a remote site, after skull trauma or surgery, and, rarely, following meningitis. In at least 15% of cases, no source can be identified.
  • Imaging depends on the various stages of the disease.
  • MRI is more sensitive than CT scan in the assessment of cerebral abscess.
  • Differential diagnosis include metastasis, high grade glioma, subacute infarction or hemorrhage and radiation necrosis.
Author: radhianahassan