Parallel volume visualization is of interest to a variety of applicati
on areas since current single-processor systems fall short in interact
ively rendering complex, large-sized datasets. This article presents a
survey of volume-visualization methods on general-purpose parallel ar
chitectures, with special attention being paid to medical imaging appl
ications. First, the various approaches to volume visualization are br
iefly discussed, followed by a description of relevant aspects of para
llel architectures. Next, the implications of the various architecture
s are illustrated on the basis of a number of existing implementations
of visualization algorithms on parallel architectures and their resul
ts. For parallel volume visualization, multiple instruction, multiple
data (MIMD) architectures are found to be superior to single instructi
on, multiple data (SIMD) architectures. The latter type suffers from a
lack of performance as well as flexibility. For most applications of
interactive volume visualization, including the important area of medi
cal imaging, shared memory MIMD architectures are preferred over distr
ibuted memory MIMD architectures. The ease of programming of shared me
mory architectures allows existing algorithms to be readily implemente
d without loss of performance or flexibility.