Quantitative 3-dimensional imaging of murine neointimal and atherosclerotic lesions by optical projection tomography

Traditional methods for the analysis of vascular lesion formation are labour intensive to perform - restricting study to 'snapshots' within each vessel. This study was undertaken to determine the suitability of optical projection tomographic (OPT) imaging for the 3-dimensional representation and quantification of intimal lesions in mouse arteries.

Vascular injury was induced by wire-insertion or ligation of the mouse femoral artery or administration of an atherogenic diet to apoE-deficient mice. Lesion formation was examined by OPT imaging of autofluorescent emission. Lesions could be clearly identified and distinguished from the underlying vascular wall. Planimetric measurements of lesion area correlated well with those made from histological sections subsequently produced from the same vessels (wire-injury: R²  =  0.92; ligation-injury: R²  =  0.89; atherosclerosis: R²  =  0.85), confirming both the accuracy of this methodology and its non-destructive nature. It was also possible to record volumetric measurements of lesion and lumen and these were highly reproducible between scans (coefficient of variation  =  5.36%, 11.39% and 4.79% for wire- and ligation-injury and atherosclerosis, respectively).

These data demonstrate the eminent suitability of OPT for imaging of atherosclerotic and neointimal lesion formation, providing a much needed means for the routine 3-dimensional analysis of vascular morphology in studies of this type.