Investigation of Diffuse Axonal Injury in Rats Induced by the Combined Linear and Rotational Accelerations Using Diffusion Tensor Imaging

Abstract

<div class="section abstract"><div class="htmlview paragraph">Diffuse Axonal Injury (DAI) is the most common type of traumatic brain injury, and it is associated with the linear and rotational accelerations resulting from head impacts, which often occurs in traffic related and sports accidents. To investigate the degree of influence of linear and rotational acceleration on DAI, a two-factor, two-level rat head impact experimental protocol involving linear and rotational acceleration was established using the L<sub>4</sub>(2<sup>3</sup>) orthogonal table in this paper. Following the protocol, rats head was injured and diffusion tensor imaging (DTI) was performed at 24h post-injury to obtain the whole brain DAI injury, and the fractional anisotropy (FA) value of the corpus callosum was selected as the evaluation indicator. Using analysis of variance, the sum of squared deviations for the evaluation indicators was calculated to determine the degree of influence of linear acceleration and rotational acceleration on DAI. The results show that, 1. For the corpus callosum, the degree of influence of linear and rotational acceleration on DAI was 39.6% and 56.0%, respectively. 2. The degree of influence of linear and rotational acceleration to the corpus callosum's genu, body, and splenium are as follows: genu - linear: 38.6%, rotational: 50.9%; body - linear: 53.5%, rotational: 29.4%; splenium - linear: 29.2%, rotational: 60.5%.3. At 0.7 MPa impact strength, the highest mortality rate (42.9%) was observed in rats with restrained head rotational movements. This study provides a method for quantifying the degree of influence of linear and rotational acceleration on DAI, and the results can be helpful for the development of head protection equipment.</div></div>