This case demonstrates a traumatic septum pellucidum hemorrhage in the setting of a motor vehicle accident. The patient was a restrained driver in a vehicle that was t-boned. They were able to self-extricate and ambulate independently following the accident. She denied any loss of consciousness. The patient was not on any anti-coagulation medication. No prior imaging was available for comparison.

Initial imaging demonstrated the small hyperdensity in the posterior septum pellucidum. Repeat imaging was performed 24 hours following initial presentation which confirmed initial suspicions of a septum pellucidum hemorrhage with interval increase in the size of the hyperdensity. The patient was observed and apart from a headache, demonstrated no other neurological symptoms. MRI brain performed two days after initial presentation also demonstrated small-volume interventricular extension, however the patient remained asymptomatic. The patient was discharged home and remained asymptomatic with short-interval outpatient follow-up.

A potential pitfall considering the hyperdensity a thrombosis of the inferior sagittal sinus, which runs along the inferior (free) edge of the falx cerebri from anterior to posterior. In this case, it is easily distinguishable as hemorrhage by using the coronal and sagittal views.