image data in a movie or cinematographic (cine) mode, whereby a rotating
3-D image is seen on the monitor screen. This type of presentation identi-
fies the location of a lesion in an organ in relation to other organs in the
body.
In cardiac, brain, and respiratory studies, a popular technique called the
bull’s eye, or polar map, method is employed in which the activities in each
transverse slice are displayed on a circumferential profile. The circumfer-
ential profile of each slice is projected on a bull’s-eye format where the
intensity of a point in the slice represents the magnitude of the activity, and
the location of the point represents the radial location of the slice (Fig.
11.3). In polar images, the activity distribution in an object is essentially
unfolded from inside out, and three-dimensional data are presented in a
two-dimensional format. The major advantage of this technique is that one
can identify the location of the defect in relation to adjacent areas on a
single image.
Software and DICOM
As already mentioned, software is a collection of instructions for the com-
puter to perform in carrying out a particular imaging study. Different
vendors develop software programs, which are proprietary to them to
operate their own equipment, and it is difficult to use one vendor’s soft-
ware for another’s equipment. Also, there are third-party companies who
develop software specific for equipment of a particular vendor. To partially
circumvent such situations, one may stick to one vendor all the time using
the same software. However, the American College of Radiology and the
National Engineering Manufacturing Association (NEMA) jointly spon-
sored a standard format for the software, called Digital Imaging and Com-
Application of Computers in Nuclear Medicine 149Fig. 11.3. A typical illustration of a bull’s eye or polar map image.