Northern lights phenomenon
Citation, DOI & article data
The northern lights phenomenon represents an echogenic band slowly descending distal to the ultrasound transducer, and is exclusively seen during high mechanical index (MI) B-mode scanning after the administration of ultrasonic contrast media. It is not to be confused with prolonged heterogeneous liver enhancement.
The phenomenon appears as an echogenic, veil-like band migrating distally. It is caused by microbubbles bursting due to the high MI of the ultrasound beam. The bursting microbubbles are shielding contrast media distally to them, thus the band appears to slowly descend on the image as the wavefront of microbubble burst propagates 1-3.
The northern lights phenomenon was first decribed with earlier CEUS contrast agents, where high MI scanning was routine part of the diagnostic protocol. With novel contrast media, this scanning technique resulting in microbubble burst is generally discouraged during the CEUS exam, but nonetheless can still be encountered if B-mode is used after the completion of the examination 1-3.
- 1. https://wfumb.info/2020/03/10/december-com-2-2/
- 2. Skjoldbye B, Pedersen M, Struckmann J, Burcharth F, Larsen T. Improved Detection and Biopsy of Solid Liver Lesions Using Pulse-Inversion Ultrasound Scanning and Contrast Agent Infusion. Ultrasound in Medicine & Biology. 2002;28(4):439-44. doi:10.1016/s0301-5629(02)00484-2
- 3. Wilson S, Burns P, Muradali D, Wilson J, Lai X. Harmonic Hepatic US with Microbubble Contrast Agent: Initial Experience Showing Improved Characterization of Hemangioma, Hepatocellular Carcinoma, and Metastasis. Radiology. 2000;215(1):153-61. doi:10.1148/radiology.215.1.r00ap08153 - Pubmed