Presentation
Fall from bike.
Patient Data
The left frontal subdural hematoma measures 10 mm in depth and mildly effaces the subjacent left frontal lobe sulci. Small volume adjacent subarachnoid blood. There is 4 mm of midline shift towards the right at the level of the septum pellucidum. Subdural hematoma also noted at the posterior falx cerebri and extending onto the left tentorium cerebelli, measuring 3 mm.
A small hyperdense focus in the left occipital lobe is compatible with a small hemorrhagic contusion. No hydrocephalus. No intracranial mass. No skull fractures are noted, although a bone algorithm reconstruction has not been performed on this study.
Using subdural windows (e.g. width: 250-400; level: 40) makes the acute blood easily distinguishable from the adjacent bone.
Case Discussion
Reviewing all CT brains on "brain window", "bone window" and "subdural window" is an important habit and will allow you to see lesions which are otherwise subtle or invisible on single "brain window" setting.