X-ray computed tomography#Multiplanar reconstruction
The multiplanar reformatting (also multi- planar reformat (MPR ) or multiplanar reconstruction called ) is a method of two-dimensional image reconstruction, which is used, inter alia, in computer tomography (CT ), nuclear medicine, but also in magnetic resonance imaging (MRI).
In the CT as well as in the SPECT image reconstruction algorithm from the raw data is always generated first transverse cuts. In the first generations of equipment this was the only possible form of image representation.
In the MPR are frontal from these transverse sections, sagittal, calculated and presented in order to help the viewer with the anatomical orientation oblique or curved cuts. Slant ( oblique ) sections, for example, in cardiac imaging helpful ( four-chamber view, short- axis slices ), curvilinear reconstructions along itself repeatedly bent extending structures for the visualization of vessels (such as the coronary arteries) or the ureters.
In order to obtain high-quality MPR reconstructions, the image data in the CT should be overlapping recorded in low layer thickness. In addition, a small layer thickness should be chosen to avoid step artifacts in image reconstruction. Summation of multiple layers of the image noise can be reduced. The availability of isotropic voxel brought a diagnostic gain for many questions. Isotropic voxels have in all three spatial directions the same spatial resolution, so that an oblique MPR reconstruction no distortion evident. Isotropic voxel is calculated by a CT scanner with selection of a suitable recording and reconstruction protocol; is taken with a high pitch, oblique reconstructions in the Z direction will be blurred.
In the magnetic resonance imaging not isotropic voxels are often available; in layers carried out recordings, the resolution in the image plane is much higher than perpendicular to it and instead of MPRs additional shots for each image to be displayed activity will be complemented. In contrast to CT, PET and SPECT, the original data thus are often already in the form of sagittal or Coronalschnitten, so that these representations do not have to be calculated.
For several years, special 3D imaging sequences are used in MRI, which can generate high-resolution isotropic image voxels and thus allow an artifact-free MPR representation.
- Björn Loewenhardt: Diagnostic Imaging - Scientific Self- Verlag, 3rd revised edition 2006, ISBN 3-00-017189-4 - Chapter 11.8.5: New applications in MSCT
- H. von Tengg - Kobligk, T. F. Weber, F. Rengier, D. Boeckler, H. Schumacher, H.-U. Kauczor. Current image postprocessing of aortic CTA and MRA. In: The radiologist. Vol 47, No. 11, 2007, pp. 1003-1011. PMID 17943264; doi: 10.1007/s00117-007-1583-8.
- Template: Internet resource / maintenance / access date not in ISO format Philip Gabriel: experimental study to compare the image quality of multiplanar reformations and axial cross-sectional images of computed tomography based on vertebral specimens. In: Inaugural- Dissertation for Doctor of Medicine degree. Faculty of Medicine, Albert -Ludwigs -Universität Freiburg im Breisgau, 2004, accessed on April 24, 2009 (PDF, 9.5 MB, German ).
- Imaging method (medicine)
- Medicine computer science