Double oblique multiplanar reconstruction
Double oblique is a type of multiplanar reconstruction used in cardiac cross-sectional imaging. It is useful for an accurate assessment of the ascending aorta and aortic annulus, and is particularly useful for pre- and post-procedure evaluation of a transcatheter aortic valve replacement (TAVR).
To form a double oblique plane, the PACS must be capable of free manipulation of planes. All three standard planes (axial, coronal, and sagittal) should be visible to form the double oblique. The reference lines should be fixed at 90 degrees.
- start in the standard axial plane at the approximate level of the aortic valve
- use the coronal plane to tilt the axial plane parallel to the aortic annulus
- move the new obliqued axial plane to the level of the first cusp insertion point
- center the crosshairs exactly on to this first cusp insertion point
- then move the oblique axial plane up and down to find the second cusp insertion point
- turn the reference line of the standard sagittal plane to exactly cross the second cusp insertion point (now an obliqued sagittal plane)
- now adjust the obliqued axial plane so it crosses both cusps in the obliqued sagittal plane
- finally turn the remaining free dimension into a plane that contains the third coronary cusp
After following these steps, the doubly-obliqued axial plane is now in a plane that is parallel to the aortic valve. This plane can then be used for accurate measurement of the aortic annulus.
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- 2. Achenbach S, Delgado V, Hausleiter J et-al. SCCT expert consensus document on computed tomography imaging before transcatheter aortic valve implantation (TAVI)/transcatheter aortic valve replacement (TAVR). J Cardiovasc Comput Tomogr. 2012;6 (6): 366-80. doi:10.1016/j.jcct.2012.11.002 - Pubmed citation