High-signal venous sinuses on MR angiography: discrimination between reversal of venous flow and arteriovenous shunting using arterial spin labeling

• Published in: Neuroradiology Vol. 63; no. 6; pp. 889 - 896
• Main Authors: Iwamura, Masatoshi, Midorikawa, Hiroshi, Shibutani, Koichi, Kakuta, Akihisa, Maruyama, Sho, Yotsuya, Chihiro, Tatsuo, Soichiro, Fujita, Hiromasa, Kakehata, Shinya, Tsushima, Fumiyasu, Nozaki, Atsushi, Sugimoto, Koichiro, Kakeda, Shingo
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-06-2021; Springer Nature B.V
• Subjects: Angiography; Diagnostic Neuroradiology; Imaging; Jugular vein; Labeling; Magnetic resonance imaging; Medical imaging; Medicine; Medicine & Public Health; Neurology; Neuroradiology; Neurosciences; Neurosurgery; Radiology; Reversed flow; Sinuses; Spin labeling; Digital subtraction angiography; Dural arteriovenous fistulas; Venous reverse flow; Magnetic resonance angiography; Arterial spin labeling; Cavernous sinuses
• ISSN: 0028-3940; 1432-1920
• DOI: 10.1007/s00234-020-02588-5

Purpose
It is sometimes difficult to differentiate between high signals originating from a reverse flow on magnetic resonance angiography (MRA) and occult arteriovenous shunting. We attempted to determine whether arterial spin labeling (ASL) can be used to discriminate reversal of venous flow from arteriovenous shunting for high-signal venous sinuses on MR angiography.
Methods
Two radiologists evaluated the signals of the venous sinus on MRA and ASL obtained from 364 cases without arteriovenous shunting. In addition, the findings on MRA were compared with those on ASL in an additional 13 patients who had dural arteriovenous fistula (DAVF).
Results
In the 364 cases (728 sides) without arteriovenous shunting, a high signal due to reverse flow in the cavernous sinuses (CS) was observed on 99 sides (13.6%) on MRA and none on ASL. Of these cases, a high signal in the sigmoid sinus, transverse sinus, and internal jugular vein was seen on 3, 3, and 8 sides, respectively. All of these venous sinuses showed a high signal from the reverse flow on MRA images.
Conclusion
ASL is a simple and useful MR imaging sequence for differentiating between reversal of venous flow and CS DAVF. In the sigmoid and transverse sinus, ASL showed false-positives due to the reverse flow from the jugular vein, which may be a limitation of which radiologists should be aware.