Image: Monitoring arteriogenesis at the cerebral arteriolo-arteriolar anastomoses (AAAs) in mouse brain during middle cerebral artery occlusion using OCT-based microangiography (OMAG) (left) and Doppler OMAG (right).
Optical coherence tomography based microangiography provides an ability to longitudinally image arteriogenesis in vivo. Yuandong Li, Woo June Choi, Wan Qin, Utku Baran, Lauren M. Habenicht, Ruikang K. Wang. Journal of Neuroscience Methods. Volume 274, 1 December 2016, Pages 164-172.
Arteriogenesis describes the active growth of the pre-existing collateral arterioles, which is a crucial tissue-saving process in occlusive vascular diseases.
We propose to use optical coherence tomography (OCT)-based microangiography (OMAG) to monitor arteriogenesis following artery transection in mouse ear and focal stroke in mouse brain.
Our longitudinal mouse ear study shows that the growth phase of arteriogenesis, indicated by changes in collateral vessel diameter and velocity, occurs between 12 and 24 h after vessel transection. Additionally, the magnitude of local inflammation is consistent with the time course of arteriogenesis, judging by the tissue thickness measurement and lymphatic vessel signals in OCT. In the mouse brain study, collateral vessel morphology, blood flow velocity and directionality are identified, and an activation of the collateral flow at the arteriolo-arteriolar anastomoses (AAA) is observed during stroke.
Comparison with existing methods
In comparison with histology and fluorescence imaging, OCT/OMAG is completely non-invasive and capable of producing consistent results of longitudinal changes in collateral vessel morphology and vasodynamics.
OCT/OMAG is a promising imaging tool for longitudinal study of collateral vessel remodeling in small animals. This technique can be applied in guiding the in vivo experiments of arteriogenesis stimulation to treat occlusive vascular diseases, including stroke.