Contributed by
Boston Children's Hospital
Vishesh Jain.
History
4-month-old male infant with clinical concern for increased intracranial pressure.
Images (Click any image to enlarge)
Axial T2-weighed MRI through the brain.
Coronal MRA MIP of the brain.
Question
Which is the most likely diagnosis?
Your answer
Please log in to see your results.
Correct answer
Pial arteriovenous fistula
Discussion
MRI and MRA demonstrate an enlarged vascular structure at the left sylvian fissure which appears to be supplied by the left MCA and drains into cortical veins coursing toward the superior sagittal sinus. There is no visible intervening mass or tangle of vessels. These findings are consistent with a pial AVF.
Most pial AVF are supratentorial. There may be a single or multiple arteriovenous connections.
Differential diagnosis
- Aneurysm - would account for a dilated vascular structure supplied by the MCA, but would not explain the prominent cortical veins
- AVM - may be similar to these findings, but would expect a nidus
- Dural AVF - would be supplied by a dural artery, such as the middle meningeal artery
- Vein of Galen malformation - would be located posteriorly and near midline, in the region of the median promesencephalic vein
References
- S.W. Hetts, K. Keenan, H.J. Fullerton, et al. "Pediatric Intracranial Nongalenic Pial Arteriovenous Fistulas: Clinical Features, Angioarchitecture, and Outcomes." American Journal of Neuroradiology Oct 2012, 33 (9) 1710-1719; DOI: 10.3174/ajnr.A3194