Presentation
Headache then impaired consciousness in a patient with valve replacement receiving anticoagulants.
Patient Data
A crescentic shaped abnormality - a feature of hematoma - is seen along the right side of cerebral parenchyma.
It is isodense compared to the adjacent cerebral parenchyma. It exerts mass effect in the form of effacement of the related cortical sulci, compression of the right lateral ventricle with slight midline shift.
Right sided subdural hematoma, better characterized on MRI, with mass effect.
Case Discussion
A subdural hematoma is the presence of blood between the dura and arachnoid mater of the meninges, so it is termed extra-axial.
In the subacute stage, a subdural hematoma appears isodense to surrounding brain parenchyma. This makes it hard to be differentiated from brain parenchyma. Note its indirect effect in the form of mass effect described above.
MRI offers more characterization of aging hematoma. It appears bright on T1 and on T2 owing to extracellular methemoglobin of late subacute hematoma.