Maximum intensity projection images

Fig. 2.2.15 Desktop MR microscope system overview (top left) yokeless permanent magnet (top right) and maximum intensity projection image of a blue berry (bottom).

CTA is the best noninvasive test and has high accuracy for detecting proximal intracranial artery occlusions. Maximum intensity projection images fadlitate lesion detection... 

Fig. 3.4a-d. Fast 3D FSPGR Tl-weighted protocol, a Small hypervascular lesion is depicted during the arterial phase after paramagnetic contrast media administration arrow), b-d Coronal maximum intensity projection images of arterial (b, c) and venous (d) phase can be useful in the assessment of vascular anatomy... 

The bottom image in Figure 2.2.15 is a maximum intensity projection of a 100 xm cubic-resolution 3D-image dataset of a blue berry acquired with this system. The network structure of the fruit is clearly visualized. If the MRI console and permanent magnet can be made smaller, a true desktop or handy M R microscope will then be constructed. 

Fig. 2. Soft tissue imaging can be accomplished in pre- and postnatal specimens by micro-CT. Top rowdepicts a maximum intensity projection or WIIP view of an El 5 mouse embryo left) and PO mouse pup (right). Bottom rowdepicts a 2D slice view, technically termed a reformat, of the same El 5 (left) and PO (right) from the data set depicted above. The soft tissue features can be seen along with skeletal signal as volumetric or two-dimensional slices of the specimen in all anatomical viewing planes, including oblique angles, if desired.

The basic evaluation includes the visual assessment of whole body images, using a 3D viewer, and the analysis of maximum intensity projection (MIP) images. Furthermore, a quantitative analysis of suspicious lesions and reference areas is recommended. 

Figure 2 The Sertoli cell extends from the base of the seminiferous tubule (bottom right) to the lumen (upper left) and has numerous cytoplasmic projections that surround and support germ cells. In this maximum intensity projection of 13 series confocal images, a single Sertoli cell in an intact seminiferous tubule is visible because of green fluorescent protein expression following adenovirus infection. The Sertoli cell nucleus is visible in the basal cytoplasm surrounded by brightfluorescence. The overall length ofthis Sertoli is approximately 100 /xm.

Noncontrast and contrast MRA can be postprocessed as maximum intensity projection (MIP) images. This technique first creates a three-dimensional model of the vessels from the MRA raw data. A set of parallel rays are then drawn from the model and the highest intensity along each ray is projected to form a two-dimensional MIP image. Multiple projections of the model are created from different vantage points so that... 

The membranous labyrinth is relatively easier to represent in three dimensions than the bone labyrinth since data are directly acquired by MR. The initial method applied to MR for 3D display of the labyrinth was the MIP (maximum intensity projection). The final image that is obtained represents a projectional roadmap of the labyrinthine components. The simplicity of using MIP has made it the most widely used algorithm for 3D imaging even in this case but since MIP results from summed inten-... 

Fig. 15.7. Volume-rendered image and maximum intensity projection of a CTA dataset of a patient with two overlapping thoracic stents in the thoracic aorta. CTA also displays normal abdominal aorta and ectatic iliac arteries...

Fig. 15.8. Volume-rendering technique of peripheral run-off study post-processed in standardized fashion with AP, PA, LAO and RAO views. The arteries are always well-displayed in their superficial course. Maximum intensity projections are well-suited for demonstrating the course of the arteries after segmentation of the hones. However, this technique is time-consuming and does not always deliver consistently high image quality...

Soyer P, Dufresne AC, Somveille E, Scherrer A (1996b) Focal nodular hyperplasia of the liver assessment of hemodynamic and angioarchitectural patterns with gadolinium chelate-enhanced 3D spoiled gradient-recalled MRI and maximum intensity projection reformatted images. JCAT 20 898-904... 

CT and MR source images may be processed to generate 3D reconstructions, which can be obtained with both external and endoluminal points of view of the organ anatomy. The maximum intensity projection (MIP), the minimum intensity projection (MinlP), the shaded surface display (SSD), the perspective volume rendering (VR), and the multiplanar volume reconstruction (MPVR) algorithms pro-... 

Three-dimensional medical images of CT and MR data sets can be generated with a variety of computer algorithms. The three most commonly used techniques are shaded surface display (SSD), maximum intensity projection (MIP) and 3D volume rendering (Calhoun et al. 1999). 

The sliding thin slab maximum intensity projection (STS-MIP) and multiplanar volume reconstruction (MPVR) represent alternatives to MIP in which the volume is restricted to a thin slab that is only few voxel widths in depth (Napel et al. 1993). Pre processing is no longer required and the resulting images have a high contrast resolution. 

Watabe T, Furuse M (1996) Intracranial aneurysms diagnostic accuracy of MR angiography with evaluation of maximum intensity projection and source images. Radiology 199 199-207... 

This approach can be used to extract further clinically relevant information from CT scans acquired at normal dose levels. For example, it is possible to identify iodine in liver or kidney tissue and to display the contrast enhancement either by colorcoding it in the CT image or by subtracting it to obtain virtual unenhanced images. This also works in lung tissue for the evaluation of pulmonary perfusion. Also, bones can be eliminated from angiography datasets by the spectral properties of calcium so that the evaluation of vessels becomes easier and faster in a maximum intensity projection. Applications without contrast material include the differentiation of kidney stones and the depiction of tendons and ligaments. 

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