Segmentation is a new concept that has significantly made it possible to use EPI on most of the conventional imaging systems where constraints related to signal to noise would have otherwise prevented EPI. Segmenting EPI is increasingly becoming more important to a number of its properties that ensure improved image quality as compared to the conventional single shot EPI. For example, one of the potential benefits of segmentation is that it allows EPI to be able to effectively run on the conventional systems where single short EPI can not be used. This is because segmentation ensures less stress is placed on the gradients as opposed to single short EPI and is therefore critically important in situations where by the available SNR and hardware makes it difficult to acquire all the necessary k-space data before the elimination of the MR signal by the traverse relaxation (McRobbie et al., 2003, p.Another important advantage of segmented EPI is that it helps reduce the magnetic susceptibility of various artefacts. This is because phase errors often have less time to build up when segmented EPI as compared to single shot EPI. The shortening of echo train length also allows segmented EPI to be less prone to the effects of artefact variations. Segmentation can also be used to help reduce imaging distortion and enable higher image resolution as compared to single shot EPI.The other key benefit of segmentation of EPI is the fact that it can be used to increase resolution. This is particularly attributed to the fact that segmented EPI have relatively short echo train length, thereby leading to increased spatial resolution. On the other hand, normal single shot EPI usually have lower spatial resolution, and this makes segmentation more preferable. The shortening of echo train length also allows segmented EPI to be less susceptible to a number of variations as well as allow for the introduction of T1 weighing. Consequently, segmentation has made it easier to use EPI on most imaging systems where constraints are related to signal to noise, which was not previously possible with the single shot EPI.Although segmented EPIs offer numerous benefits, using more segments, however, comes with a number of disadvantages that can potentially affect the image quality. Some of the limitations of segmentation include the fact that performing segmented EPI usually takes longer scanning time as compared to single shot EPI.
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