Jugular bulb venous thrombosis caused by mild head injury: a case report

We present here the first report of a jugular bulb venous thrombosis after mild head injury, which lacked either a skull fracture or abnormal findings on CT scan.

An 8-year-old boy was hit on the back of the head and experienced headache and vomiting beginning the next morning. A CT scan and cranial x-ray examination failed to reveal any abnormal findings. The patient was treated conservatively; however, his headache and vomiting persisted. At 13 days after the injury, he began to show double vision due to left VIth nerve palsy and bilateral papilloedemas, suggesting an increased ICP. Although repeated CT scan failed to detect abnormal findings in both the supra- and infra-tentorial regions, MRI clearly visualized a thrombus which was situated within the right jugular bulb. Furthermore, MRV demonstrated disruption of venous flow at the jugular bulb. The patient was administered heparin continuously. His symptoms improved and the CSF pressure on lumbar puncture returned to a normal level at 20 days after admission. Magnetic resonance imaging showed resolution of the clot, and MRV appeared to demonstrate partial recanalization simultaneously. The patient was discharged without any neurologic deficits. The clot in the jugular bulb disappeared completely after 4 months, and he could be followed up for 1 year.

This case underscores the fact that MRI may represent the exclusive screening examination in cases of sinus thrombosis when it occurs within the jugular bulb, as CT scan fails to reveal any findings suggestive of venous thrombosis.