Skip to main content
. Author manuscript; available in PMC: 2012 Jul 18.
Published in final edited form as: Sci Transl Med. 2012 Jan 18;4(117):117ra8. doi: 10.1126/scitranslmed.3002670

Figure 2. Flow analysis indicates that AVM narrowing is the primary event in AVM regression.

Figure 2

(A&B) Two-photon timelapse imaging of cortical brain vessels through cranial window in Notch4* mutant mice. Vessel topology was visualized by plasma labeling by intravenous FITC-dextran. Centerline velocity in the regressing AV shunt, feeding artery (FA) and adjacent artery (AA) was obtained by direct measurement of the velocity of individual red blood cells. Repression of Notch4* decreased blood flow velocity by 48hrs in shunt and feeding artery, but increased velocity in adjacent artery. (C) Summary of % Δ in calculated flow in vessels either 48hrs after Notch4* suppression or after 48hrs with no Notch4* suppression. (D) Illustration of empirical data and hypothetical scenarios of regression. The primary event can be either the acute narrowing of the AV shunt or a reduction in flow, caused by either steal from an adjacent artery or a systemic reduction in flow. The acute AV shunt narrowing model, predicting the increase in adjacent artery flow and reduction in feeding artery flow, best fits the empirical observations. We do not observe increased feeding artery flow, as predicted by the adjacent artery “steal” model, or a decrease in adjacent artery flow, as predicted by systemic flow reduction model. Scale bars = 50μm.