1. Non Contrast Head CT Patterns in Moderate to Severe Traumatic Brain Injury Results: Out of 712 patients with moderate to severe TBI: 89.6% (n=638) had Intracranial Hemorrhage, 9.5% (n=68) had No Intracranial Hemorrhage in their Head CT reports, and 0.8% (n=6) had missing reports (Figure 1). No visible intracranial compression in 54.5% (n=388), Midline shift of 0-5mm in 26.5% (n=189), Midline shift of greater than 5mm in 17.9 % (n=128) was noted in head CT reports (Figure 2). The patients with Intracranial Hemorrhage had TBI due to the following causes: 54.9% Vehicular Accidents (n=350), 17.2% Falls (n=110), 10% Pedestrians (n=64), 7% Assault (n=45), 5.8% Gunshot Wound (n=37), 3.1% Sports (n=20), and 1.8% Other (n=12) (Figure 3). Of the 638 patients with Intracranial Hemorrhage: 67.9% Subarachnoid Hemorrhage (n=433), 45.6% Subdural Hemorrhage (n=291), 23.6% Non-Cortical Hemorrhage (n=151), 25.9% Intraventricular Hemorrhage (n=165), 19.9% Punctuate Hemorrhage (n=127), and 14.2% Epidural Hemorrhage (n=91) (Figure 4). The percentage of frontal hemorrhage is highest when compared to other types of hemorrhage regardless of the cause of injury (61.8% fall, 53.7% vehicle, 60% assault), except pedestrians where temporal hemorrhage (48.4%) is slightly higher than frontal (46.8%) (Figure 5, Table 1). Conclusions: Based on these findings, frontal and temporal lobes are the most frequently involved areas for focal cortical parenchymal contusion or hemorrhage for all TBI etiologies which may help plan intervention targeting temporal (memory) and frontal (executive function) deficits. Further research is suggested to investigate additional outcome measures such as length of post- traumatic amnesia, Extended Glasgow Outcome Scale, Disability Rating Scale, Functional Independence Measure, and Supervision Rating Scale to understand the impact of different intracranial hemorrhages on patient outcomes. Objectives: To describe the patterns between causes of injury and intracranial hemorrhages in non-contrast head CT reports of patients with moderate to severe traumatic brain injury (TBI). Methodology: Non-contrast head CT reports taken within the first seven days of TBI were studied in a total of 712 patients (Mean Age = 32 years, SD 17.5) admitted in Santa Clara Valley Medical Center between 1989 and 2014 included in the Traumatic Brain Injury Model System (TBIMS) database. The original radiology report was reviewed and coded for intracranial compression; intracranial hemorrhage and/or contusions; the presence or absence of punctate/petechial hemorrhages, subarachnoid hemorrhage, intraventricular hemorrhage; the presence of focal cortical parenchymal contusions or hemorrhage in cerebral cortex, focal non-cortical parenchymal contusions (non-hemorrhagic or hemorrhagic) or hemorrhage; presence of any extra-axial collection and entered into the TBIMS database. Saranya P. Balakrishnan M.D., Reza Ehsanian M.D. PhD., Laura Jamison CBIS, Samantha Sechrist B.S., Nhung Quach M.D., James D. Crew M.D. & Linda Isaac PhD. Santa Clara Valley Medical Center, Rehabilitation Research Center Epidural Hemorrhage Fronto-Termporal Hemorrhage Frontal Hemorrhage with Occipito-Parietal Hemorrhage CT Images of Intracranial Compression, Hemorrhage and / or Contusion Results: Patient Count (n) FrontalTemporalParietalOccipital N o of Cases Reported % of Patients N o of Cases Reported % Of Patients N o of Cases Reported % of Patients N o of Cases Reported % of Patients Vehicular35018853.7113438.299126195.43 Fall1106861.825348.182926.36109.09 Pedestrian643046.883148.441421.88914.06 Assault4527602044.441431.1136.67 Gun372156.761437.841848.6525.41 Patterns of Focal Cortical Parenchymal Contusion or Hemorrhage in various causes of TBI Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Table 1