Medical Student Research Fellowship for Summer 2011
Mentors: Ramon Diaz-Arrastia, MD, PhD, Anne Hudak, MD
Department: Neurology, Department of Physical Medicine and Rehabilitation
Room number: F2.318
Mail Code: 9036
Phone number: 214-648-6409
E-mail: Ramon.Diaz-Arrastia@UTSouthwestern.edu, Anne.Hudak@UTSouthwestern.edu
Project title: Evaluation of Diffuse Axonal Injury in patients with Traumatic Brain Injury Using Diffusion Tensor Imaging;
Human subjects IRB approved project numbers (where applicable): IRB # 012005-073; 012004-003; and 0399-123
Animal subjects IRB approved project number (where applicable): Not applicable
Project Type: Patient-oriented research
Brief Description of Projects:
Traumatic brain injury (TBI) is a major cause of mortality and morbidity, particularly among persons below the age of 45. In the US, approximately 55,000 deaths each year are attributed to TBI, and an additional 50,000 individuals each year suffer long-term physical and psychological problems that limit their independence and ability to work. TBI is a heterogeneous disease, and multiple pathophysiologic mechanisms may be operating to produce neural injury. The TBI Research Center at UT Southwestern has several projects suitable for participation during the summer by medical students.
Diffuse Axonal Injury (DAI) results from high velocity deceleration and shear strain, and is believed to be the predominant mechanism of injury in 40 - 50% of TBIs requiring hospital admission in the US. CT scanning is usually unrevealing in DAI, and while structural MRI scanning may add some sensitivity, currently used neuroimaging methods are not associated with injury severity of predictive of outcome. The anatomy and integrity of white matter fiber tracts can be determined noninvasively with DTI, providing new information about brain networks and connectivity.
The fellow will primarily work with Anne Hudak (Physical Medicine and Rehabilitation) and Carlos Marquez de la Plata (Clinical Psychology) to determine connectivity between TBI patients and mood. There has only been one previously published paper on mechanisms of brain networks in depression (Sheline Y et.al. (2010) Resting-state functional MRI in depression unmasks increased connectivity between networks via the dorsal nexus. PNAS, 107:11020-11025). The study showed that the dorsal nexus demonstrated increased fMRI connectivity with established brain networks in patients with depression. The project will use similar fMRI evaluation techniques to evaluate if there is a connection between patients who have experienced TBIs and mood.
The fellow will be primarily involved in identifying eligible patients, prospectively collecting clinical information relating to the severity of the initial traumatic injury, following the patients daily during their acute hospitalization, as well as obtaining outcome data at 6 months post-injury. These tasks will be accomplished by having the fellow attend daily morning rounds with the neurosurgical service at Parkland Memorial Hospital, identifying patients who meet eligibility criteria for the study, obtaining informed consent from patients or family members, and collecting intake information. Afternoons will be spent obtaining outcome information via telephone interviews and analyzing MRI data using MRICro and DTI Studio.
Previous Research Activities or Publications with Medical Students:
Fifteen medical students have done summer research in Dr. Diaz-Arrastia's laboratory over the past 11 years. This has led to 20 abstracts presented at national meetings and 10 publications.