No visible differences appeared when viewing the results in FSLview.  T tests were performed using the previously mentioned contrast images as statistical maps, overlaid across the brain template.  Based on the t tests performed, there was no evidence to support differences in cortical thickness between TBI and OI groups in either direction (p = 0.05).  
Discussion
    The results failed to support the hypothesis, and cortices of TBI participants were not, in fact, significantly thinner than those of OI control participants.  These findings stand in contrast to conclusions drawn from previous studies.  Several confounding variables may exist, however, and could have reasonably made contributions to the null effect observed here.  For example, injury severity has been identified as a key factor in some brain structure outcomes.  One study found that the severity of injury strongly predicted not only short term structural damage, but also long term recovery of white matter among pediatric participants (Genc et al, 2017).  Perhaps a similar phenomenon could occur in recovery of cortical thickness, and thus a lack of injury severity may be hindering the ability to differentiate between OI and TBI patients.  In future studies, a wider spectrum of injury severities should be examined.    
    Elapsed time since the incidence of injury also seems to be a critical factor in pediatric cortical thickness.  In one study comparing pediatric TBI and OI patients, for example, TBI patients exhibited cortical thinning at 3 months post injury in superior frontal, dorsolateral frontal, orbital frontal, and anterior cingulate regions of the cortex.  At an 18 month follow up, additional regions of cortical thinning emerged.  However, some regions originally identified as exhibiting cortical thickness now no longer were statistically different from controls (Wilde, 2012).  It is possible that images in the present study were merely obtained at a time where cortical thickness had rebounded to some degree in TBI patients, and naturally thinned among OI patients.  The respective thickness of both participant groups is subject to fluctuate however, and may feasibly cross over at some points.  This could contribute to the null effect currently observed, which may be obscuring a significant effect that can only be tracked longitudinally.  The acute nature of this study, therefore, may be a serious limitation. 
    While no effect was observed in this study, the literature remains inconclusive.  Extensions of this study, including more severely injured patients followed longitudinally, may prove useful in establishing the true relationship between TBI and cortical thickness.   
References
Dennis, E. L., Hua, X., Villalon-Reina, J., Moran, L. M., Kernan, C., Babikian, T., & ... Asarnow, R. F. (2016). Tensor-based morphometry reveals volumetric deficits in     moderate=severe pediatric traumatic brain injury. Journal Of Neurotrauma33(9), 840-852. doi:10.1089/neu.2015.4012
Dennis, E. L., Rashid, F., Ellis, M. U., Babikian, T., Vlasova, R. M., Villalon-Reina, J. E., & ... Asarnow, R. F. (2017). Diverging white matter trajectories in children after traumatic     brain injury: The RAPBI study. Neurology88(15), 1392-1399. doi:10.1212/WNL.0000000000003808
Genc, S., Anderson, V., Ryan, N. P., Malpas, C. B., Catroppa, C., Beauchamp, M. H., & Silk, T. J. (2017). Recovery of white matter following pediatric traumatic brain injury     depends on injury severity. Journal Of Neurotrauma34(4), 798-806. doi:10.1089/neu.2016.4584
Hayes, J. P., Logue, M. W., Sadeh, N., Spielberg, J. M., Verfaellie, M., Hayes, S. M., & ... Miller, M. W. (2017). Mild traumatic brain injury is associated with reduced cortical     thickness in those at risk for Alzheimer’s disease. Brain: A Journal Of Neurology140(3), 813-825.
Merkley, T. L., Bigler, E. D., Wilde, E. A., McCauley, S. R., Hunter, J. V., & Levin, H. S. (2008). Diffuse changes in cortical thickness in pediatric moderate-to-severe traumatic     brain injury. Journal Of Neurotrauma25(11), 1343-1345. doi:10.1089/neu.2008.0615
Michael, A. P., Stout, J., Roskos, P. T., Bolzenius, J., Gfeller, J., Mogul, D., & Bucholz, R. (2015). Evaluation of cortical thickness after traumatic brain injury in military     veterans. Journal Of Neurotrauma32(22), 1751-1758. doi:10.1089/neu.2015.3918
Urban, K. J., Riggs, L., Wells, G. D., Keightley, M., Chen, J., Ptito, A., & ... Sinopoli, K. J. (2017). Cortical thickness changes and their relationship to dual-task performance     following mild traumatic brain injury in youth. Journal Of Neurotrauma34(4), 816-823. doi:10.1089/neu.2016.4502
Wang, X., Xie, H., Cotton, A. S., Tamburrino, M. B., Brickman, K. R., Lewis, T. J., & ... Liberzon, I. (2015). Early cortical thickness change after mild traumatic brain injury     following motor vehicle collision. Journal Of Neurotrauma32(7), 455-463. doi:10.1089/neu.2014.3492
Wilde, E. A., Merkley, T. L., Bigler, E. D., Max, J. E., Schmidt, A. T., Ayoub, K. W., & ... Levin, H. S. (2012). Longitudinal changes in cortical thickness in children after traumatic     brain injury and their relation to behavioral regulation and emotional control. International Journal Of Developmental Neuroscience30(3), 267-276.     doi:10.1016/j.ijdevneu.2012.01.003