Presentation
Pediatric patient with a known case of tetralogy of Fallot has fever and severe headache.
Patient Data
There is a well-defined, lobulated, rim-enhancing area of low attenuation at the right frontoparietal gray-white matter junction with surrounding edema and slight compression of the body of the right lateral ventricle. A smaller similar-looking lesion is seen in the left frontal gray-white matter junction.
An extraaxial low-attenuating area with enhancing borders is seen at the right parietal convexity with associated focal compression of the adjacent brain parenchyma.
The imaged cerebral vessels appear hyperdense. This may be due to increased viscosity of the blood secondary to possible polycythemia.
An area of increased density is seen in the left cerebellar hemisphere, which on contrast study shows a bunch of small veins draining towards a prominent vein that runs to the left cerebellopontine angle region adjacent to the transverse sinus. This is an incidental finding of developmental venous anomaly.
Case Discussion
Patients with congenital cyanotic heart disease are at risk of developing brain abscess, and tetralogy of Fallot is the most common cardiac anomaly associated with brain abscess.
In patients with left-to-right shunt, venous blood bypasses the pulmonary circulation wherein bacteria in the bloodstream is filtered. Patients with cyanotic heart disease have areas of low perfusion in the brain, commonly at the gray-white matter junction, which are prone to bacterial seeding that may be present in the blood stream.