Cerebrospinal fluid pulsatile segmentation - a review

Cerebrospinal fluid (CSF) plays an important role to protect the brain from minor external damages as well as preserving the nutrients for the central nervous system (CNS) and stabilizing the chemical regulation in the system. In most cases, many neurodegenerative disorders such as hydrocephalus and Alzheimer´s diseases may affect the normal volume and pressure of the CSF flow within brain and CNS. Thus, analyses on these complex behaviors have become substantially important. Recent studies showed that the use of cine phase contrast magnetic resonance imaging (PC-MRI) has facilitated further understanding of the CSF flow movements due to its capability to analyze the pulsatile motions over a specific range of time. However, the main drawback of the technique is the presence of partial volume effect, which cause blurring boundary between the CSF and the soft tissue regions. In this paper, we review the current progress on developing effective image segmentation methods that may assist to overcome the partial volume effect of the images. Firstly, the basic of the CSF and its pulsatile motion within brain are introduced. Then, the current image segmentation methods are discussed and this leads to the recent trend and direction of the CSF pulsatile segmentation.