  Traumatic brain injury (TBI) is caused by a sudden trauma to the head that
may result in hematomas and contusions and can lead to stroke or chronic
disability. An accurate quantification of the lesion volumes and their
locations is essential to understand the pathophysiology of TBI and its
progression. In this paper, we propose a fully convolutional neural network
(CNN) model to segment contusions and lesions from brain magnetic resonance
(MR) images of patients with TBI. The CNN architecture proposed here was based
on a state of the art CNN architecture from Google, called Inception. Using a
3-layer Inception network, lesions are segmented from multi-contrast MR images.
When compared with two recent TBI lesion segmentation methods, one based on CNN
(called DeepMedic) and another based on random forests, the proposed algorithm
showed improved segmentation accuracy on images of 18 patients with mild to
severe TBI. Using a leave-one-out cross validation, the proposed model achieved
a median Dice of 0.75, which was significantly better (p<0.01) than the two
competing methods.
