Multiplanar reconstruction

Fig. 17.2a,b. PAVM diagnosed using CT with multiplanar reconstructions. CT obtained in axial view (a) and coronal maximum intensity projection view (b) shows a single PAVM of the left lower lobe. The feeding artery, aneurysmal sac and draining vein are easily identified... 

For anticipated multiplanar reconstructions or 3D rendering, use thinnest detector width (e.g. 0.625 mm) with 16-slice at all ages. 

The anterior column corresponds to the ili-opectineal line on an AP radiograph and the posterior column the ilioischial line. Judet views allow more detailed examination of the acetabular columns, although these have largely been super-ceded by CT examination. The internal (obturator) oblique view is taken with the pelvis rotated anteriorly by 45° and shows the iliopectineal line and posterior wall of the acetabulum, but again CT is more useful and allows multiplanar reconstructions. 

At present two different multiplanar reconstruction techniques have been developed section display and texture mapping. 

Fig. l.la-c. Surface rendering for fetal imaging, showing a 30-week-old fetus (a), volume-rendering methods for liver imaging (b) and multiplanar reconstruction of a focal nodular hyperplasia in the liver (c) (courtesy of ESAOTE)... 

The near isotropic imaging obtained by spiral CT allows not only the accurate evaluation of anatomic details on native images, but even the reconstruction of oblique planes (MPR, multiplanar reconstructions) (Ali et al. 1993 Hermans et al. 1995). MPRs are well known since the introduction of CT in the clinical practice. Initial applications of MPR to the study of the middle ear were carried out with conventional CT (Haas and Kahle 1988 Grevers et al. 1989), and such experiences addressed to MPR an effective integrative role in CT imaging of the middle ear. With the advent of spiral CT, MPRs have been made available for most users, and the frequency of their application in the clinical routine has increased. 

Watanabe Y, Sugai Y, Hosoya T, Yamaguchi K, Aoyagi M (2000) High-resolution computed tomography using multiplanar reconstruction for the facial nerve canal. Acta Otolaryngol 542 44-48... 

Fig. 18.15. Interactive application for evaluation of virtual dissection using the 3D local flattening approach. Seven different windows are shown on the computer screen left upper corner virtual dissection of the colon using the 3D local flattening approach (constant angle sampling). The red vertical line depicts the position of the virtual camera, which is used for anatomic cross-referencing on the ohter views. Upper right corner magnified view from the left. Middle row, center view from above. Middle row, right virtual endoscopic view. Lower row axial CT slice and multiplanar reconstructions (coronal, sagittal) at the position of the virtual camera. Whenever the position of the virtual camera is moved upwards or downwards with the cursor keys, all windows are updated automatically...

Achenbach S, Moshage W, Ropers D, Bachmann K (1998) Curved multiplanar reconstructions for the evaluation of contrast enhanced electron beam CT the coronary arteries. Am J Roentgenol 170 895-899... 

Brugel M, Link TM, Rummeny EJ et al (2004) Assessment of vascular invasion in pancreatic head cancers with multislice CT value of multiplanar reconstructions. Eur Radiol 14 1188-1195... 

Fractures analysis is frequently based on the axial sections as well as on multiplanar reconstructions (MPRs) and 3D surface shaded rendering. However, although MPR allows precise quantification of the displacement of the fragments, it does not display a global... 

The CT should demonstrate the entire central airway system, i.e., a spiral data set should be obtained from the mouth to the segmental bronchi. In order to show potential postobstructive complications, the CT should be extended to the diaphragm. To allow appropriate postprocessing of the spiral data set obtained in transversal orientation, collimation should be 2-3 mm, the pitch factor should be 1.5-2, overlap index in reconstruction should be 30%-50%, and a low spatial algorithm should be used. Images should be displayed both at mediastinal and pulmonary window settings. Multiplanar reconstructions and three-dimensional reconstructions as well as virtual endoscopy can be obtained with the... 

Ropers D, Baum U, Pohle K, et al. (2003) Detection of coronary artery stenoses with thin-slice multi-detector row spiral computed tomography and multiplanar reconstruction. Circulation 107 664-666... 

Table 14.1. Traimia protocol Scan und reconstruction parameters for MSCT of midface and paranasal sinuses (mAs above 100 for the diagnosis of malignant disease). Additional convolution kernels are necessary for tumor evaluation and i.v. contrast administration. Sagittal and coronal multiplanar reconstructions are mandatory...

Table 14.2. Tumor protocol Scan und reconstruction parameters for MSCT of nasopharynx, oropharynx (including oral cavity), and hypopharynx. Blood parameters about renal (creatinin) and thyroid (TSH) function should be obtained before Lv. contrast application. The scan range should be chosen from the skull base till the aortic arch to evaluate intracranial tumor spread or suspect lymphoid node stations. Sagittal and coronal multiplanar reconstructions (MPRs) are mandatory. Delay can be varied for more highly vascularized tumors to achieve good contrast ...

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