Abstract:
In present study, a reference based technique has been proposed to segment midbrain structures in 3D Magnetic Resonance (MR) images using multi-resolution non-rigid registration.
The proposed scheme segmented the mid-brain structures in two stages. During first stage, a target
image was registered to an already segmented reference image while in second stage, segmentation
information was mapped from reference to target medical image. Using this scheme, the aim was to
segment nine mid-brain structures including left ventricle, right ventricle, third ventricle, anterior
commissure, posterior commissure, left putamen, right putamen, left caudate nucleus and right caudate
nucleus. Results of automatic segmentation achieved through reference based non-rigid registration
were validated by comparing with the manual segmentation, considered as ground truth. Three metrics
namely Dice Coefficient, Sensitivity and Positive Predictive Values were used for assessing the
segmentation results. The proposed algorithm showed the satisfactory segmentation of mid-brain
structures by achieving a mean sensitivity of 89. 85 % for five target MR images. The results indicated
that the proposed scheme performed accurate segmentation of mid-brain structures.
