31-year-old female complains of aphasia for two hours yesterday. Patient is postpartum two weeks. Rule out dissection. CT of brain without infusion.No definitive evidence of any area of edema, mass effect, midline shift, hydrocephalus or hemorrhage is detected. Follow-up with an MRI is recommended.The cortical sulci, ventricular system and all CSF cisterns are essentially normal for patient stated age.The bony density of calvarium, pneumatization of paranasal sinuses and mastoid air cells are also unremarkable.CTA of the cervical region:Right carotid system.The origin of right common carotid artery is normal. The entire course of right common carotid artery, right carotid bifurcation, right internal carotid artery and right external carotid artery remain within normal limits.Left carotid system:The origin of left common carotid artery and entire course of the left common carotid artery remains normal.There is an abrupt sharp reduction in the caliber of the internal carotid artery from its origin distally which is believed to represent a dissection. There is a very narrow string of flow in an interrupted pattern is noted through the cervical region. This extends from the origin of left internal carotid artery to the skull base. The left internal carotid artery across the skull base has a small lumen however remains patent. The small lumen of the left internal carotid artery across the skull base may be due to diminished flow and not dissection.CTA of vertebral basilar system.A dominant normal appearing right vertebral artery in the cervical and across the skull base is noted.A smaller left vertebral artery which appears normal from its origin through the skull base.CTA of intracranial circulation:The supraclinoid portion of both internal carotid arteries are patent. There is also normal visualization of bilateral middle and anterior cerebral arteries. The left internal carotid artery immediately below the left anterior clinoid demonstrates reduction in its caliber.CTA of vertebral basilar system demonstrate patent bilateral vertebral arteries across the skull base with no pathology. There is also normal visualization of basilar artery and all of its branches with no pathology.On source images there is evidence of a patent anterior communicating artery and a small patent left posterior imaging artery.
1.No definitive evidence of pathology on CT examination of brain. Please follow-up with an MRI.2.Dissection of the left internal carotid artery at its origin which appears to extend superiorly to the skull base. A string of lumen of left internal carotid artery is noted in the cervical region which appears to have a interrupted segment immediately below the skull base.3.Unremarkable CTA of the cervical region of other vasculature.4.Essentially unremarkable CTA of intracranial circulation.5.Reduced caliber of left internal carotid artery across the skull base.