MRI BRAIN WITH AND WITHOUT CONTRAST:
CLINICAL HISTORY: 52-year-old man with history of neuroendocrine tumor, on anticoagulation, evaluate for hemorrhage or intracranial metastasis. Also history of anoxic brain injury after suicide attempt by hanging 20 years ago.
FINDINGS:
Parenchyma: There are innumerable, small, rounded
ring-enhancing lesions scattered throughout the supratentorial and infratentorial brain, greater than 20, involving all lobes, as well as the
midbrain,
left ventral thalamus,
right middle cerebellar peduncle, and
bilateral cerebellar hemispheres. Lesions demonstrate
central restricted diffusion. There is mild associated surrounding
vasogenic edema without mass effect. Imaging appearance is most consistent with multiple cerebral abscesses given diffusion pattern, with likely lung source especially given pulmonary vein thrombosis. Largest lesion is in the right cerebellar hemisphere measuring up to 13 mm, remainder are subcentimeter. Several
subependymal lesions are seen along the left lateral ventricle, no definite ependymal or ventricular enhancement. There is also irregular enhancement in the
left optic chiasm, likely representing an additional lesion. Global parenchymal volume loss, likely related to history of anoxic brain injury. There is a
left frontal developmental venous anomaly incidentally noted. No evidence of acute hemorrhage. No mass effect or midline shift.
Ventricles and extra-axial spaces: Ventricular prominence commensurate with global volume loss.
Orbits: Normal.
Visualized paranasal sinuses: Mild mucosal thickening in the ethmoid air cells and right frontal sinus.
Mastoid air cells: Clear.
Bones: Diffusely heterogeneous bone marrow without focal lesion.
Additional comment: None.
IMPRESSION:
1. Multiple (greater than 20), ring-enhancing lesions in the supratentorial and infratentorial brain, with central restricted diffusion, favored to represent abscesses given diffusion pattern and extensive lung infection with pulmonary vein thrombosis as likely source. Correlation with CSF analysis would be useful. Also consider atypical organisms (e.g. fungal). Follow-up recommended as smaller lesions without central cavitation would be impossible to distinguish from superimposed metastases. No evidence of hemorrhage or mass effect.