Mild Head Trauma Patients Research Articles

Antikoagülan ve/veya Antiplatelet Tedavi Kullanan Hafif Kafa Travmalı Hastalarda Başlangıçta Normal olan Bilgisayarlı Kafa Tomografisini Tekrarlamamız Gerekir mi?

Objective: Patients using anticoagulant and/or antiplatelet (AC/AP) medications are at an increased risk of intracranial hemorrhage (ICH) subsequent to head trauma and current guidelines recommend a head computed tomography (CT) scan for these patients. There is a lack of consensus about management recommendations for mild head trauma patients on AC/AP treatment who had an initially normal head CT. The aim of this study was to determine the rate of delayed ICH after a 24-hour observation in patients with mild head trauma using AC/AP who had an initially normal head CT. Method: Patients aged 18 and older, using AC/AP drugs with mild head trauma were included prospectively. Patients underwent head CT for suspected bleeding. A repeat CT scan was performed after a 24-hours observation period for the patients who had an initially normal head CT for detecting delayed intracranial hemorrhage. Result: A total of 101 patients were included and, 57.4% (n=58) of the patients were female. Delayed ICH was detected in 2.9% (n=3) of the patients after a 24-hour observation. None of the patients with delayed ICH needed surgical treatment or further intervention. Delayed ICH was found in patients who used acetylsalicylic acid (n=1), dabigatran (n=1), and apixaban (n=1). Conclusion: In patients with mild head trauma using AC/AP, delayed intracranial hemorrhage is rare and may be clinically insignificant. A repeat CT scanning after 24-hour observation may not be necessary for patients with mild head trauma using AC/AP therapy who had initially normal head CT.

Findings on Repeat Posttraumatic Brain Computed Tomography Scans in Older Patients With Minimal Head Trauma and the Impact of Existing Antithrombotic Use.

Evaluate the utility of routine rescanning of older, mild head trauma patients with an initial negative brain computed tomography (CT), who is on a preinjury antithrombotic (AT) agent by assessing the rate of delayed intracranial hemorrhage (dICH), need for surgery, and attributable mortality. Participating centers were trained and provided data collection instruments per institutional review board-approved protocols. Data were obtained from manual chart review and electronic medical record download. Adults ≥55 years seen at Level I/II Trauma Centers, between 2017 and 2019 with suspected head trauma, Glasgow Coma Scale 14 to 15, negative initial brain CT, and no other Abbreviated Injury Scale injuries >2 were identified, grouped by preinjury AT therapy (AT- or AT+) and compared on dICH rate, need for operative neurosurgical intervention, and attributable mortality using univariate analysis (α=.05). A total of 2,950 patients from 24 centers were enrolled; 280 (9.5%) had a repeat brain CT. In those rescanned, the dICH rate was 15/126 (11.9%) for AT- and 6/154 (3.9%) in AT+. Assuming nonrescanned patients did not suffer clinically meaningful dICH, the dICH rate would be 15/2001 (0.7%) for AT- and 6/949 (0.6%) for AT+. No surgical operations were done for dICH. All-cause mortality was 9/2950 (0.3%) and attributable mortality was 1/2950 (0.03%). The attributable death was an AT+, dICH patient whose family declined intervention. In older patients with an initial Glasgow Coma Scale of 14 to 15 and a negative initial brain CT scan, the dICH rate is low (<1%) and of minimal clinical consequence, regardless of AT use. In addition, no patient had operative neurosurgical intervention. Therefore, routine rescanning is not supported based on the results of this study.

Nausea control in mild head trauma patients: Effectiveness of metoclopramide and ondansetron in the emergency department in a double-blind study.

Mild head trauma often causes several complications and disabilities including nausea and vomiting in hospitalized people. The aim of the present study was to compare the effectiveness of metoclopramide and ondansetron, and compare it with placebo to control nausea in the patients with mild head trauma admitted to the emergency department. This is a randomized double-blind placebo-controlled clinical trial conducted on the patients with mild head trauma and normal brain CT scans who were admitted to the emergency department within 24 hours after the injury. The subjects were randomly divided into three groups of ondansetron (n= 41), metoclopramide (n= 44), and placebo (n= 39), and the severity of nausea and vomiting was assessed using the visual analogue scale (VAS). A total of 124 patients with mild head trauma were included in the study. The assessment of the VAS scores during the study showed that over time, the patients in all three groups had reduced nausea (p<0.01). On the other hand, the percentage change of the VAS score indicated that metoclopramide and ondansetron had the greatest changes (46.97% and 66.90%, respectively) within 15 and 30 minutes after the injection, respectively. The results of the present study showed that ondansetron and metoclopramide had similar effects on nausea in the patients with mild head trauma. However, metoclopramide was most effective in 15 minutes and ondansetron in 30 minutes after the injection.

Rates of Intracranial Hemorrhage in Mild Head Trauma Patients Presenting to Emergency Department and Their Management: A Comparison of Direct Oral Anticoagulant Drugs with Vitamin K Antagonists.

Background and objectives: Anticoagulants are thought to increase the risks of traumatic intracranial injury and poor clinical outcomes after blunt head trauma. The safety of using direct oral anticoagulants (DOACs) compared to vitamin K antagonists (VKAs) after intracranial hemorrhage (ICH) is unclear. This study aims to compare the incidence of post-traumatic ICH following mild head injury (MHI) and to assess the need for surgery, mortality rates, emergency department (ED) revisit rates, and the volume of ICH. Materials and Methods: This is a retrospective, single-center observational study on all patients admitted to our emergency department for mild head trauma from 1 January 2016, to 31 December 2018. We enrolled 234 anticoagulated patients, of which 156 were on VKAs and 78 on DOACs. Patients underwent computed tomography (CT) scans on arrival (T0) and after 24 h (T24). The control group consisted of patients not taking anticoagulants, had no clotting disorders, and who reported an MHI in the same period. About 54% in the control group had CTs performed. Results: The anticoagulated groups were comparable in baseline parameters. Patients on VKA developed ICH more frequently than patients on DOACs and the control group at 17%, 5.13%, and 7.5%, respectively. No significant difference between the two groups was noted in terms of surgery, intrahospital mortality rates, ED revisit rates, and the volume of ICH. Conclusions: Patients with mild head trauma on DOAC therapy had a similar prevalence of ICH to that of the control group. Meanwhile, patients on VKA therapy had about twice the ICH prevalence than that on the control group or patients on DOAC, which remained after correcting for age. No significant difference in the need for surgery was determined; however, this result must take into account the very small number of patients needing surgery.

Validity of Serum miRNA 93 and miRNA 191 to Reduce Unnecessary Computed Tomography in Patients With Mild Head Trauma.

BackgroundIndication for the appropriate use of cranial computed tomography (CCT) in patients with mild head trauma (MHT) based on history and physical examination alone remains unclear. Recent studies have been reported that 90% of patients with MHT who undergo CCT under the present clinical decision rules have no clinically important brain injuries. We aimed to investigate whether peripheral blood expression of microRNA 93 (miR93) and microRNA 191 (miR191) in patients with MHT can predict the presence or absence of intracranial injury, reducing the unnecessary use of CCT.MethodsFifty-nine consecutive adult patients with isolated MHT undergoing CCT based on the clinical decision guidelines of the New Orleans criteria and 91 age- and sex-matched controls were enrolled in this prospective observational cohort study. Patients were divided into two groups: those without or with traumatic intracerebral or extracerebral lesions identified by CCT. Patients were further divided into two subgroups based on the presence or absence of traumatic parenchymal lesions defined as traumatic brain injury (TBI).ResultsMean serum miR93 and miR191 levels differed significantly between study groups. Of the 79 patients investigated, 16 exhibited trauma-relevant lesions on CCT scan (CCT+). With a cut-off limit of 0.15, miR191 had an area under the curve value of 0.765 (0.640 - 0.889), with sensitivity of 68.1% and specificity of 68.8% in CCT+ patients. Compared to MHT patients without TBI, mean serum miR191 levels were markedly elevated in patients with TBI. However, miR93 levels did not exhibit significant changes in either group.ConclusionsCirculating miRNA levels increased after MHT and differentiated patients with and without intracranial or extracranial lesions demonstrable on CCT. Adding the measurement of serum miRNAs particularly miR191 to the clinical decision rules for a CCT scan in patients with MHI could allow a reduction in scans.

The increase in copeptin levels in mild head trauma does not predict the severity and the outcome of brain damage.

To investigate the copeptin prognostic role in mild head trauma. We enrolled 105 adult patients who entered the emergency room because of recent mild head trauma; we evaluated: clinical picture, imaging and laboratory data (including copeptin). Copeptin resulted higher in mild head trauma patients compared with controls: 29.89pmol/l versus 7.05pmol/l (p=0.0008). Copeptin failed in identifying patients with or without brain lesions detected by CT scan, and patients with or without adverse events during the 30days follow-up. We confirmed that mild head trauma patients have a significantly higher copeptin plasma levels compared with controls. Nevertheless, we did not observe a significant role for copeptin in traumatic brain injury patients regarding brain damage and outcome.

Effect of clinical decision rules, patient cost and malpractice information on clinician brain CT image ordering: a randomized controlled trial

BackgroundThe frequency of head computed tomography (CT) imaging for mild head trauma patients has raised safety and cost concerns. Validated clinical decision rules exist in the published literature and on-line sources to guide medical image ordering but are often not used by emergency department (ED) clinicians. Using simulation, we explored whether the presentation of a clinical decision rule (i.e. Canadian CT Head Rule - CCHR), findings from malpractice cases related to clinicians not ordering CT imaging in mild head trauma cases, and estimated patient out-of-pocket cost might influence clinician brain CT ordering. Understanding what type and how information may influence clinical decision making in the ordering advanced medical imaging is important in shaping the optimal design and implementation of related clinical decision support systems.MethodsMulti-center, double-blinded simulation-based randomized controlled trial. Following standardized clinical vignette presentation, clinicians made an initial imaging decision for the patient. This was followed by additional information on decision support rules, malpractice outcome review, and patient cost; each with opportunity to modify their initial order. The malpractice and cost information differed by assigned group to test the any temporal relationship. The simulation closed with a second vignette and an imaging decision.ResultsOne hundred sixteen of the 167 participants (66.9%) initially ordered a brain CT scan. After CCHR presentation, the number of clinicians ordering a CT dropped to 76 (45.8%), representing a 21.1% reduction in CT ordering (P = 0.002). This reduction in CT ordering was maintained, in comparison to initial imaging orders, when presented with malpractice review information (p = 0.002) and patient cost information (p = 0.002). About 57% of clinicians changed their order during study, while 43% never modified their imaging order.ConclusionThis study suggests that ED clinician brain CT imaging decisions may be influenced by clinical decision support rules, patient out-of-pocket cost information and findings from malpractice case review.Trial registrationNCT03449862, February 27, 2018, Retrospectively registered.

Scandinavian guidelines for initial management of minor and moderate head trauma in children.

BackgroundThe management of minor and moderate head trauma in children differs widely between countries. Presently, there are no existing guidelines for management of these children in Scandinavia. The purpose of this study was to produce new evidence-based guidelines for the initial management of head trauma in the paediatric population in Scandinavia. The primary aim was to detect all children in need of neurosurgical intervention. Detection of any traumatic intracranial injury on CT scan was an important secondary aim.MethodsGeneral methodology according to the Appraisal of Guidelines for Research and Evaluation (AGREE) II and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used. Systematic evidence-based review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology and based upon relevant clinical questions with respect to patient-important outcomes. Quality ratings of the included studies were performed using Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 and Centre of Evidence Based Medicine (CEBM)-2 tools. Based upon the results, GRADE recommendations, a guideline, discharge instructions and in-hospital observation instructions were drafted. For elements with low evidence, a modified Delphi process was used for consensus, which included relevant clinical stakeholders.ResultsThe guidelines include criteria for selecting children for CT scans, in-hospital observation or early discharge, and suggestions for monitoring routines and discharge advice for children and guardians. The guidelines separate mild head trauma patients into high-, medium- and low-risk categories, favouring observation for mild, low-risk patients as an attempt to reduce CT scans in children.ConclusionsWe present new evidence and consensus based Scandinavian Neurotrauma Committee guidelines for initial management of minor and moderate head trauma in children. These guidelines should be validated before extensive clinical use and updated within four years due to rapid development of new diagnostic tools within paediatric neurotrauma.Electronic supplementary materialThe online version of this article (doi:10.1186/s12916-016-0574-x) contains supplementary material, which is available to authorized users.

Evaluation the frequency of computerized tomography (CT) scan indication in children under two years old with mild trauma

Objective: Head traumas are prevalent in children with mild severity and without commitment of delayed brain injuries. The aim of present study was to detect the mild head trauma (MHT) children with high risk of brain injuries for avoidance of unnecessary interventions. Methods: This cross-sectional study considered 100 children under 2 years old with MHT in Kashani and Alzahra Hospitals between March 2011 and August 2011, Isfahan, Iran. Data was gathered by these project executives including the radiologist reports and the patients past medical history. The patients were divided into normal and abnormal CT scan and reduction of consciousness level, vomiting and the other variables were considered. Results: The results were obtained from evaluation of 100 files from the patients with mean age 18±7.1 month. CT scan findings showed that 55 percent of the patients were abnormal and had burn injuries including skull fracture, epidural hemorrhage, skull contusion, and arachnoids hemorrhage. The incidence of repeated vomiting and reduction of consciousness level in patients with non-normal CT scan was more than normal group while this difference was not significantly different. Also according to CT scan findings there was no statistically significant difference between patients with repeated vomiting or reduced consciousness level (P&gt;0.05). Conclusions: This study results showed that there is not significantly difference between vomiting incidence, deceased level of consciousness and CT scan results. These criteria were not considered separately as only factors for burn trauma of performing CT scan in MHT patients. DOI: http://dx.doi.org/10.3329/bjms.v13i2.15053 Bangladesh Journal of Medical Science Vol.13(2) 2014 p.140-144

A strategy to optimize CT use in children with mild blunt head trauma utilizing clinical risk stratification; Could we improve CT use in children with mild head injury?

AimThe purpose of our study was to investigate the impact of clinical risk classification on optimization of the rationale of CT scanning in children with mild blunt head trauma. Exposed effective radiation dose values of CT scanning were also evaluated. MethodsChildren with isolated pediatric mild head trauma admitted in a single center over a 5-year period (n=3102, >2 years and <16 years of age) were retrospectively reviewed. The study group comprised 806 patients with a mean age of 7.4±2.1 years (range, 2–15 years). The patients were categorized into low and high risk groups with regard to presence of predefined signs and symptoms. Effective radiation dose values were calculated. ResultsIncidences of the pathologic CT findings related to trauma were significantly different between low (n=10) 1.9% and high (n=90) 29.8% risk groups. Certain predefined signs and symptoms (e.g., vomiting, suspected skull fracture and loss of consciousness) were related significantly with pathologic CT findings attributed to trauma. Estimated mean effective dose values were 3.91±0.38mSv for 2-6 year old (n=557), and 3.33±0.12mSv for 7-16 year old patients (n=349). ConclusionThe pediatric victims of mild head trauma patients within high risk group and those with vomiting, suspected skull fracture and loss of consciousness should undergo head CT scanning. The manufacturer settings on the CT scanners for children should be revised to alleviate untoward radiation exposure.

The mean platelet volume is decreased in patients with mild head trauma and brain injury

We planned a prospective study to assess platelet number and size in patients with or without brain injury after mild head trauma (MHT). Platelet count and mean platelet volume (MPV) were assessed in consecutive patients admitted to the emergency department with isolate MHT, as well as in healthy blood donors who served as controls. The study population consisted in 54 patients with MHT, 13 of whom (24%) with intracranial lesions suggestive for brain injury, and 339 healthy blood donors. The value of platelet count was significantly lower in patients with MHT and positive computerized tomography than in healthy controls (P = 0.014). The vales of MPV progressively decreased from healthy controls (11.1 fl) to patients with MHT and negative computerized tomography (9.8 fl; P < 0.001), and further to patients with MHT and positive computerized tomography (8.6 fl; P < 0.001). The MPV was significantly lower in patients with MHT and positive computerized tomography than in those with negative computerized tomography (P = 0.002). As compared with healthy controls, the frequency of decreased MPV values was 10-fold and 17-fold higher in MTH patients with negative and positive computerized tomography, respectively. The MPV exhibited an area under the curve of 0.74 (95% CI, 0.58 to 0.89; P < 0.001) for differentiating MHT patients with positive computerized tomography from those with negative computerized tomography. MHT patients display a larger prevalence of small and hyporeactive platelets. This observation provides a reliable basis for planning further studies to establish whether MPV may be useful for diagnostic evaluation of MHT in the emergency department.

Peripheral blood picture following mild head trauma in children

The aim of the present study was to investigate changes in peripheral white blood cell, and differential counts following mild head trauma in a pediatric population. Fifty-one patients (mean age, 79 +/- 62 months) with mild head trauma (Glasgow Coma Scale [GCS] score 15) who were admitted to the emergency department, were studied. Two blood specimens were collected from each patient, one on arrival and one after 24 h at the emergency department. Complete blood count was performed using a hemocytometer and the absolute cell counts for each sample were calculated after examination of peripheral smear. No patient developed any complication during the hospital stay or after discharge. Significant differences were found for white blood cell, neutrophil, and immature cell counts just after and 24 h after trauma (P = 0.047, 0.039 and 0.009, respectively). Mild head trauma may cause an increase in white blood cell, neutrophil and band counts in children just after trauma. In a child with a mild head trauma, who is asymptomatic, with GCS score of 15 and absence of risk factors, and without clinical deterioration, complete blood cell count may be omitted from laboratory workup. But a prospective randomized study comparing mild head trauma patients with good and bad clinical outcome is needed to draw a definite conclusion.

Quality of life and neuropsychological changes in mild head trauma: Late analysis and correlation with S100B protein and cranial CT scan performed at hospital admission

mild head trauma (MHT) is defined as a transient neurological deficit after trauma with a history of impairment or loss of consciousness lasting less than 15 min and/or posttraumatic amnesia, and a Glasgow Coma Scale between 13 and 15 on hospital admission. We evaluated 50 MHT patients 18 months after the trauma, addressing signs and symptoms of post-concussion syndrome, quality of life and the presence of anxiety and depression. We correlate those findings with the S100B protein levels and cranial CT scan performed at hospital admission after the trauma. patients were asked to fill out questionnaires to assess quality of life (SF36), anxiety and depression (HADS), and signs and symptoms of post-concussion syndrome. For the control group, we asked the patient's household members, who had no history of head trauma of any type, to answer the same questionnaires for comparison. total quality of life index for patients with MHT was 58.16 (+/-5), lower than the 73.47 (+/-4) presented by the control group. Twenty patients (55.2%) and four (11.1%) controls were depressed. Seventeen patients (47.2%) presented anxiety, whereas only eight (22.2%) controls were considered anxious. Victims of MHT complained more frequently of loss of balance, dry mouth, pain in the arms, loss of memory and dizziness than their respective controls (p<0.05). We found no correlation between the presence of these signs and symptoms, quality of life, presence of anxiety and depression with S100B protein levels or with presence of injury in the cranial CT performed at hospital admission. MHT is associated with a higher incidence of post-concussion syndrome symptoms, lower quality of life and anxiety than their respective controls even 18 months after the trauma.

Skull radiographs and computed tomography scans in children and adolescents with mild head trauma

To identify which pediatric patients with mild head trauma are candidates for skull radiographs or cranial computed tomography (CCT) scans. Patients with mild head trauma aged from 0 to 19 years presenting to the Emergency Department of a trauma centre from Salvador City, Brazil, between May 2007 and May 2008. A total of 1888 mild head trauma patients were admitted; mean age was 7.4 (+/-5.5) years. A total of 1956 skull radiographs and 734 CCT scans were performed. About 44.4% patients with Glasgow coma score (GCS) 13 and 55.4% with GCS 14 had abnormal CCT scans. In patients with multiple traumas, 16% had abnormal findings on CCT scans. We strongly recommend routine CCT studies to patients with GCS of 13 and 14 or to multiple trauma victims, independently of score. Routine screening skull radiographs were not useful in the evaluation of mild head trauma patients in this study.

The use of brain CT Scan in craniocerebral trauma with Glasgow coma scale scores of 13 – 15 in Dr. Cipto Mangunkusumo Hospital 1999-2001

There is still a controversy among the neurologists whether brain CT scan must be performed on the mild head trauma patients. This study was executed to find out the correlation between the brain CT scan image findings and its clinical impairment among the mild head trauma patients with Glasgow coma scale (GCS) score of 13 to 15. The study was a retrospective study by analyzing the uniform medical records of the head trauma patients hospitalized at the Neurology ward of Dr. Cipto Mangunkusumo Hospital within the period of 1999 to 2001. During that period 1,663 patients were hospitalized due to head trauma, and 1,166 of them (70.1 %) were suffered from mild head trauma patients with GCS score of 13-15. Among those with brain CT scan examinations (N: 271), the neurological abnormalities were found on 144 (53.1%) of patients, consisted of cerebral edema (11,4%), intracerebral hemorrhage (5.5%), epidural hemorrhage (16.2%), subdural hemorrhage (18.1%), subarachnoid hemorrhage (5.5%), and combination (13.8%). The further analysis showed that cranial nerves disturbance, amnesia, loss of conciousness for more than 10 minutes, and vomiting are significantly correlated to the brain CT scan abnormality. Combination of the above four clinical signs and symptoms have sensitivity of 90 % in predicting brain insults. This findings may be used as a simple set of clinical criteria for identifying mild head trauma patients who need undergo CT scan examination. (Med J Indones 2004; 13: 156-60) Keywords: mild head injury, brain CT scan

Identification of Malingered Head Injury on the Wechsler Adult Intelligence Scale – 3rd Edition

Head injured patients show an IQ subtest pattern that can be discriminated from the profile produced by individuals who attempt to malinger intellectual decline due to head trauma. The current paper demonstrates that previously replicated methods for making this discrimination on the WAIS – R generalize to the WAIS – 3. The discriminant function equation accurately classified 83% of nonlitigating head-trauma patients with documented injuries and 72% of persons simulating intellectual impairment due to head trauma. A total of 45% of litigating mild head-trauma patients with purported intellectual decline but no documented loss of consciousness, hospitalization, or CT abnormality were classified as malingering by the discriminant function. A Vocabulary-Digit Span difference score provided 71% overall diagnostic accuracy, and may be informative when screening profiles by visual inspection or when complete WAIS – 3 results are unavailable.

A review of mild head trauma. part II: Clinical implications

In Binder et al. (1997) a meta-analytic review revealed a small effect size attributable to a history of mild head trauma (MHT). The results suggested a weak association between MHT and persistent neuropsychological deficits. In this paper, additional outcome data are summarized and the results are discussed. On a chronic basis, 7–8% of MHT patients remain symptomatic and 14% are disabled from work. Magnetic resonance studies of acutely injured persons may show lesions that are not detected in usual clinical practice. It is likely that the effects of these lesions dissipate with time, consistent with the neuropsychological data. The association between MHT and cognitive deficits, symptoms, and disability may not be causal; data suggest that MHT patients have more psychosocial problems prior to injury than do non-injured persons. The examiner of the MHT patient with chronic complaints must consider alternative medical and psychiatric explanations and perform a differential diagnosis. The possibility of a neurological basis for sustained neuropsychological problems cannot be completely dismissed. Presently, however, there is little evidence for neurological causation of most persisting complaints.

The Rey AVLT recognition memory task measures motivational impairment after mild head trauma

The effect of financial incentives on Rey AVLT recognition memory performance was assessed. Clinically referred mild head trauma (MHT) patients with financial incentives were compared to patients with neurologically documented brain dysfunction who did not have financial incentives. The MHT group was subdivided into a group with strong performance on a measure of motivation, the Portland Digit Recognition Test (PDRT), and a group with weak performance on the PDRT. The resulting three groups were equated on Rey AVLT acquisition, age, and education. The MHT subgroup with poor PDRT scores also was significantly impaired on recognition memory. In the total sample the prevalence of recognition scores of less than 6 correct was 27% in the MHT group and 5% in the brain dysfunction group. We conclude that severe Rey AVLT recognition memory impairment likely reflects motivation to exaggerate deficits, at least in MHT patients with no neurological evidence of brain injury.

EEG discriminant analyses of mild head trauma

Measures of EEG power spectral analyses were obtained from a total of 608 mild head trauma patients and 108 age-matched normal subjects. A training-set discriminant function was first developed from 264 mild head-injured patients and 83 age-matched controls yielding an overall discriminant classification accuracy of 94.8%. The first independent cross-validation of the discriminant function using 130 mild head trauma patients and 21 age-matched normals yielded a discriminant classification accuracy of 96.2% for the trauma patients and 90.5% for the normals. A second independent cross-validation of the discriminant function using 51 patients and measures of test-retest reliability from 93 patients yielded classification accuracies ranging between 77.8% and 92.3%. A third independent cross-validation of 70 mild head-injured patients tested at a different location with a different EEG computer system yielded a discriminant accuracy of 92.8%. The discriminating EEG power spectral analyses indicated 3 classes of neurophysiological variables which are attributable to mechanical head injury: (1) increased coherence and decreased phase in frontal and frontal-temporal regions; (2) decreased power differences between anterior and posterior cortical regions; and (3) reduced alpha power in posterior cortical regions.