Clin Nucl Med 1998 May;23(5):309-17

The purpose of this atlas is to present a review of the literature showing the advantages of SPECT brain perfusion imaging (BPI) in mild or moderate traumatic brain injury (TBI) over other morphologic imaging modalities such as x-ray CT or MRI. The authors also present the technical recommendations for SPECT brain perfusion currently practiced at their center. For the radiopharmaceutical of choice, a comparison between early and delayed images using Tc-99m HMPAO and Tc-99m ECD showed that Tc-99m HMPAO is more stable in the brain with no washout over time. Therefore, the authors feel that Tc-99m HMPAO is preferable to Tc-99m ECD. Recommendations regarding standardizing intravenous injection, the acquisition, processing parameters, and interpretation of scans using a ten grade color scale, and use of the cerebellum as the reference organ are presented. SPECT images of 228 patients (age range, 11 to 88; mean, 40.8 years) with mild or moderate TBI and no significant medical history that interfered with the results of the SPECT BP were reviewed. The etiology of the trauma was in the following order of frequency: motor vehicle accidents (45%) followed by blow to the head (36%) and a fall (19%). Frequency of the symptoms was headache (60.9%), memory problems (27.6%), dizziness (26.7%), and sleep disorders (8.7%). Comparison between patients imaged early (<3 months) versus those imaged delayed (>3 months) from the time of the accident, showed that early imaging detected more lesions (4.2 abnormal lesions per study compared to 2.7 in those imaged more than 3 months after the accident). Of 41 patients who had mild traumatic injury without loss of consciousness and had normal CT, 28 studies were abnormal. Focal areas of hypoperfusion were seen in 77% (176 patients, 612 lesions) of the group of 228 patients. The sites of abnormalities were in the following order: basal ganglia and thalami, 55.2%, frontal lobes, 23.8%, temporal lobes, 13%, parietal, 3.7%, insular and occipital lobes together, 4.6%.

Nucl Med Commun 1999 Jun;20(6):505-10

We present SPET brain perfusion findings in 32 patients who suffered mild traumatic brain injury without loss of consciousness and normal computed tomography. None of the patients had previous traumatic brain injury, CVA, HIV, psychiatric disorders or a history of alcohol or drug abuse. Their ages ranged from 11 to 61 years (mean = 42). The study was performed in 20 patients (62%) within 3 months of the date of injury and in 12 (38%) patients more than 3 months post-injury. Nineteen patients (60%) were involved in a motor vehicle accident, 10 patients (31%) sustained a fall and three patients (9%) received a blow to the head. The most common complaints were headaches in 26 patients (81%), memory deficits in 15 (47%), dizziness in 13 (41%) and sleep disorders in eight (25%). The studies were acquired approximately 2 h after an intravenous injection of 740 MBq (20.0 mCi) of 99Tcm-HMPAO. All images were acquired on a triple-headed gamma camera. The data were displayed on a 10-grade colour scale, with 2-pixel thickness (7.4 mm), and were reviewed blind to the patient's history of symptoms. The cerebellum was used as the reference site (100% maximum value). Any decrease in cerebral perfusion in the cortex or basal ganglia less than 70%, or less than 50% in the medial temporal lobe, compared to the cerebellar reference was considered abnormal. The results show that 13 (41%) had normal studies and 19 (59%) were abnormal (13 studies performed within 3 months of the date of injury and six studies performed more than 3 months post-injury). Analysis of the abnormal studies revealed that 17 showed 48 focal lesions and two showed diffuse supratentorial hypoperfusion (one from each of the early and delayed imaging groups). The 12 abnormal studies performed early had 37 focal lesions and averaged 3.1 lesions per patient, whereas there was a reduction to--an average of 2.2 lesions per patient in the five studies (total 11 lesions) performed more than 3 months post-injury. In the 17 abnormal studies with focal lesions, the following regions were involved in descending frequency: frontal lobes 58%, basal ganglia and thalami 47%, temporal lobes 26% and parietal lobes 16%. We conclude that: (1) SPET brain perfusion imaging is valuable and sensitive for the evaluation of cerebral perfusion changes following mild traumatic brain injury; (2) these changes can occur without loss of consciousness; (3) SPET brain perfusion imaging is more sensitive than computed tomography in detecting brain lesions; and (4) the changes may explain a neurological component of the patient's symptoms in the absence of morphological abnormalities using other imaging modalities.

J Head Trauma Rehabil 1998 Apr;13(2):45-52

With the growing popularity of soccer both in the United States and worldwide, reports of adverse effects of 'heading' on brain function are a source of concern. This article reviews the related research literature on neurologic and neuropsychological findings. Neurologic and neuropsychological abnormalities have been reported in a significant minority of older former professional players in Norway. Purportedly unrelated to age, the most prominent findings were cerebral atrophy and impairment on intelligence test abilities that are particularly vulnerable to brain damage. Also noteworthy in these retired players were persistent physical, cognitive, and emotional complaints consistent with a postconcussive syndrome. Younger amateur players appear to be free of major abnormalities, although some report persistent difficulties with memory and concentration. The severity of these complaints may be related to a history of soccer-related head injuries and not necessarily specific to heading. Research findings specific to heading are not more than suggestive at best, and clarification of the risks of heading a soccer ball awaits more definitive studies.

Brain Inj 1999 Mar;13(3):173-89

Epidemiology and predictors of post-concussive syndrome after minor head injury in an emergency population.

Bazarian JJ, Wong T, Harris M, Leahey N, Mookerjee S, Dombovy M

OBJECTIVE: To determine if clinical variables or neurobehavioural test (NBT) scores obtained in the ED within 24 hours of minor head injury (MHI) predict the development of postconcussive syndrome (PCS). METHODS: Prospective, observational study of 71 MHI patients and 60 orthopaedic controls. MHI defined as loss of consciousness < 10 minutes or amnesia, GCS 15, no skull fracture or new neurologic focality on PE, and no brain injury on CT (if done). All patients received a seven part NBT battery in the ED. Telephone follow-up was done at 1, 3 and 6 months to determine if patients met the DSM IV definition of PCS. ANALYSIS: Stepwise, multivariate, logistic regression. RESULTS: Predictors of PCS at 1 month were female gender (OR = 7.8; 95% CI = 41.6, 1.98), presence of both retrograde and anterograde amnesia (OR = 0.055; CI = 0.002, 0.47), Digit Span Forward Scores (OR = 0.748; CI = 0.52, 1.03) and Hopkins Verbal Learning A scores (OR = 0.786; CI = 0.65, 0.91); at 3 months, presence of both retrograde and anterograde amnesia (OR = 0.13; CI = 0.0, 0.93), Digit Span Forward Scores (OR = 0.744; CI = 0.58, 0.94). No variables fit the model at 6 months. 92% of males scoring > 25 on Hopkins Verbal Learning A did not have PCS at 1 month, and 89% of females scoring < 9 on Digit Span Forward did have PCS at 1 month. CONCLUSIONS: Gender and two NBTs can help predict PCS after MHI.

Ann Biol Clin (Paris) 1999 May;57(3):261-72

S-100 protein is an acidic calcium-binding protein with a molecular weight of 21 kDa consisting of two submits alpha and beta, which are combined to give alphaalpha (S-100a), alphabeta (S-100a) and betabeta (S-100b) dimeric forms. S-100 protein is much more abundant in the brain than in other tissus and is present as a mixture of S-100a and S-100b (named S-100beta). These two isoforms are predominantly synthesized and secreted by glial cells. Structural damage of these cells causes leakage of S-100beta protein into the extracellular compartment and into cerebrospinal fluid, further entering the bloodstream. We provide here an overview of the physicochemical properties of S-100beta protein, of its pathological aspects and of possible interest in measuring this protein in biological fluids during cerebral diseases and brain damage occurring after surgical events.

J Clin Exp Neuropsychol 1986 Aug;8(4):323-46

Seemingly mild head injuries frequently result in persisting postconcussive syndromes. The etiology of these symptoms is often controversial. Neuropsychological, neurophysiological, and neuropathological evidence that brain damage can occur in the absence of gross neurological deficits after mild injuries is reviewed. Direct impact to the head is not required to cause brain injury. Understandably, psychological factors also play a role in post-head-injury disability, but the effect of compensation claims and preinjury psychopathology is often secondary to organic factors. Persons over age 40 or with a history of previous head injury are more vulnerable to protracted symptomatology.

Brain Inj 1995 Jan;9(1):27-33

The present study examined whether patients (n = 11) with post-concussional symptoms (PCS) 12-34 months after mild head injury (MHI) performed less well on selected neuropsychological tests than patients with MHI without PCS (n = 11) and healthy controls (n = 11). Patients with PCS were individually matched with controls for the time elapsed after the injury, age, sex, education and IQ. There were no overall gross differences between the groups in cognitive functioning, except for an isolated deficit on a sustained attention task. Post-hoc analysis of results obtained with two behavioural rating scales showed that patients with higher ratings on a post-concussive/cognitive complaints scale performed less well on a sustained attention task than subjects with lower ratings.

Brain Inj 1994 Nov-Dec;8(8):701-8

There is insufficient information about the long-term sequelae of mild head injury (postconcussional symptoms, PCS). Therefore, a questionnaire-based investigation was carried out in patients 1-5 years after mild head injury (MHI) and in non-concussed subjects in order to study the nature of long-term complaints after MHI. A three-factor model of residual subjective and psychological complaints that contained a dysthymic factor, a vegetative/bodily complaints factor, and a cognitive performance factor were identified in the patient population. Three rating scales were constructed from the relevant items or factors, and were used to compare the MHI patients with non-concussed controls. It was found that the profile of distresses and discomforts mentioned by a population of MHI patients 1-5 years after the trauma was similar to that of a non-concussed control population. These symptoms were indistinguishable from those encountered in ordinary everyday life. These symptoms were significantly more severe in the MHI patients. Stepwise regression analysis in the patient population indicated that a number of parameters were statistically of predictive importance: comorbidity, sex, and neurological complication at the time of the trauma. The results support the hypothesis that MHI may not ever be completely reversible.

Brain Inj 1992 Nov-Dec;6(6):481-7

Post-concussional symptoms, such as headache, dizziness and irritability, are thought to result from the emotional stress associated with decreased cognitive performance after a head injury. A questionnaire-based investigation was carried out in 71 patients with mild head injury (MHI), using a heterogeneous item pool in order to study the interrelationships between traditional post-concussive complaints, cognitive problems, and more emotional and functional complaints. Factor analysis indicated that post-concussive symptoms loaded together with items on problems associated with decreased work performance and fatigability on a first factor, whereas psychovegetative and emotional complaints loaded together on a second factor. Two rating scales were constructed from the relevant items and were used to compare between subgroups of MHI patients and non-concussed controls. Patients with uncomplicated MHI had significantly higher scores than non-concussed subjects on the post-concussive-cognitive scale, but not on the emotional-vegetative scale. Patients with multiple head injuries or pre-existing emotional problems had higher scores on both the post-concussive-cognitive scale and the emotional-vegetative scale than MHI patients without a history of emotional problems. Reliable rating scales may be useful in multidiagnostic studies of MHI patients.

Neurosurgery 1992 May;30(5):692-5; discussion 695-6

There is much debate on the nature and duration of cognitive deficits and postconcussive symptoms (PCS) after mild head injury. Most studies performed so far have compared head-injured patients with subjects who had not suffered a concussion, instead of directly comparing patients with and without persistent PCS. The present study examined whether patients with PCS (n = 9) about 6 months after an uncomplicated mild head injury performed less well on selected neuropsychological tests than patients with mild head injuries who did not have PCS (n = 9) and healthy controls (n = 9). Patients with PCS were individually matched with controls for the time elapsed after the injury, age, sex, and education. We found that patients with PCS performed less well on tests of divided and selective attention than both patients without PCS and healthy controls. It is concluded that cognitive deficits may be present up to 6 months after mild head injury when symptoms persist. The findings indicate that patients with mild head injury and subjective symptoms may manifest demonstrable cognitive deficits.

Int J Neurosci 1992 May-Jun;64(1-4):97-105

Some patients experience persistent postconcussive symptoms (PCS) after a mild head injury (MHI). According to the coping hypothesis, PCS result from the increased stress that head-injured patients experience when they are not able to cope with environmental demands. This study examined the coping ability and cortisol reactivity of MHI patients with and without PCS and in uninjured controls. Patients with PCS 12-34 months after injury were individually matched with MHI patients without PCS (N = 11) and healthy controls (N = 11) for the time elapsed since the injury, age, sex, education, and IQ. First, we found that patients with PCS reported being less able to cope with problems. These patients appeared to be inferior in active problem solving and had a more depressive attitude toward problems than subjects of the two control groups. Second, we found no differences between the three groups in the mean cortisol response during a vigilance task. These results only partly support the coping hypothesis. With respect to cognitive performance, we found that decrements in a vigilance task were related to an increased cortisol response during this task, especially in apparently "recovered" (asymptomatic) MHI patients. The latter finding may point to an increased cognitive vulnerability of apparently recovered MHI patients when exposed to a CNS stressor.

J Neurol Neurosurg Psychiatry 1992 Mar;55(3):222-4

Patients with head injuries frequently complain of a decreased ability to endure intense light and sound stimuli. The few psychophysical studies that have objectively studied this type of hyperaesthesia have not assessed to what extent patients recover from this hyperaesthesia after mild head injury (MHI). A computerised rating technique was used to assess tolerance to intense sound (95 dB) and light (1500 lux) stimuli in patients with an uncomplicated MHI. Patients were tested 10 days and five weeks after the injury. Although most patients substantially recovered from both visual and acoustic hyperaesthesia, 25% of the patients were still not able to endure intense stimuli by five weeks. Analysis of data obtained with two behavioural rating scales (one with post-concussive/cognitive complaints and a second with emotional/vegetative complaints) indicated that visual hyperaesthesia was specifically related to the post-concussive/cognitive complaints scale.

Acta Neurol Scand 1992 Feb;85(2):116-21

There is much controversy about whether the persistence of postconcussive symptoms (PCS) in mild head injured patients (MHI) is related to the presence of cognitive deficits. Most studies performed so far have relied on normal non-concussed control subjects rather than directly comparing patients with and without PCS following MHI. In addition, subtle cognitive deficits may be present in MHI patients that are demonstrable only with more demanding cognitive tasks. In the present study the Stroop Color Word Interference Test together with a more demanding modified interference subtask was administered to two groups of patients with uncomplicated MHI 10 days, 5 weeks and 3 months after the injury. Ten patients with persistent symptoms at 3 months were selected and individually matched with MHI patients who had initially reported symptoms but who had recovered by 3 months. The scores of the two retrospectively defined groups were compared at the different time points. Between-subjects analysis revealed overall differences for both the original and modified color word interference subtask. Within-subject analysis indicated that only the recovery rate in the modified interference subtask was significantly different between the two groups. The observation that there was a parallel trend between recovery and persistence of PCS and performance on the cognitive interference measures supports the notion that there is a functional relationship between these two phenomena.

J Neurol 1991 Dec;238(8):443-6

Patients with post-concussional symptoms (PCS) about 6 months after a mild head injury (MHI) were examined for tolerance of light and sound in comparison with concussed patients without PCS and non-concussed healthy controls. MHI patients with PCS were individually matched with subjects from the two control groups for the time elapsed from the injury, and for age and sex. Using a computerized rating technique, we assessed both the maximal and submaximal levels of lowered tolerance for light and sound over a wide range of stimuli. We found that the MHI patients with PCS 6 months after the trauma (n = 11) tolerated significantly less well stimuli of intensities of 71 dB and 500 lx than MHI patients without PCS (n = 11) and non-concussed controls (n = 11). There were no significant differences in tolerance for light and sound between MHI patients without PCS and the non-injured controls. Decreased tolerance for light and sound may contribute to the persistence of symptoms up to 6 months after a mild head injury. The psychophysical method provides an objective measure for the evaluation of the late persistent post-concussional syndrome.

Emerg Med Clin North Am 1997 Aug;15(3):563-79

Patients with mild traumatic brain injury constitute the overwhelming majority of head-injured patients seen in the emergency department. The indications for radiologic imaging in these patients are still undergoing study and revision. The Glasgow Coma Scale is a widely used triage score for head injury, but is less useful at identifying which patients with mild head injuries have intracranial pathology. There have been several retrospective studies and a few prospective studies examining the indications for imaging in mild to moderate head trauma. They all show that it is not easy to predict which patients will have CT abnormalities, and that some of these patients do go on to require neurosurgery. No set of clinical predictors have yet been put together that is capable of identifying all patients who are safe to be discharged without a CT scan. Pharmacologic therapy to help reduce axonal damage after head trauma and thus minimize the postconcussive sequelae of mild traumatic brain injury remains a challenge for physicians and neurobiologists into the next century.

J Trauma 1996 Dec;41(6):976-80

BACKGROUND: Moderate or severe traumatic brain injury (TBI) resulting from cranial trauma is usually easily recognizable. Mild TBI (MTBI), however, may escape detection at presentation because of delayed symptoms and the absence of radiographic abnormalities. Despite its subtle or delayed presentation, the spectrum of symptoms often experienced after MTBI, collectively referred to as "postconcussive syndrome," may cause serious psychosocial dysfunction. METHODS/RESULTS: To assess the sensitivity of emergency department screening for MTBI, a prospective follow-up study was conducted on a group of patients (N = 129) who had been evaluated at a regional trauma center after blunt trauma. None had symptoms or signs of TBI at presentation, nor any history of direct cranial trauma. All were discharged to home from the emergency department without a diagnosis of TBI. At 1 month after injury, 41 of 129 (32%) patients described an increase in symptoms consistent with MTBI. The most common symptoms were insomnia (62%), headaches (58%), irritability (56%) and fatigue (56%). At 2 months, most symptoms had decreased significantly, and none had increased in severity. Despite improvement in their symptoms over that time period, 11% of those with persistent symptoms remained unable to resume their premorbid daily activities. CONCLUSIONS: These data, obtained from a population of patients considered to be at extremely low risk for TBI, indicate that MTBI occurs more often among blunt trauma patients than is commonly appreciated, even in busy trauma centers. Because early recognition of MTBI may expedite referral of these patients for appropriate outpatient follow-up care, thereby avoiding potentially serious social and financial repercussions, emergency department personnel should have a high index of suspicion for MTBI in any patient sustaining blunt systemic trauma. Current measures that screen for MTBI appear to be inadequate; follow-up protocols may prove to be more sensitive screening tools.

Clin J Pain 1989;5(1):77-87

Headache is a common symptom following head trauma and not related to the degree of trauma. The term post-head-trauma syndrome is used to denote a group of symptoms following head trauma. Dizziness, vertigo, perceptual changes, memory loss, paresthesias, and tinnitus have been reported as well as psychological disturbances. Pathophysiology of headache and other symptoms in the syndrome are believed to relate to vascular and neuronal disturbances. Imaging techniques may provide objective evidence of changes in the brain. Often diagnostic studies do not reveal an abnormality. Treatment consists of diagnosing the type of headache and targeting appropriate therapy. Long-term prognosis is good, the majority of patients recovering after 1 year.

Schweiz Rundsch Med Prax 1999 Dec 2;88(49):2021-4

After cervical sprain not only pain and neuropsychological disturbances may occur, but also the following sequelae: cervical dystonia, and torticollis, dizziness, hearing loss for low frequencies, dysphonia and globus. Except for dystonia the symptoms often respond to manipulation of a blocked articulation between occiput and atlas or axis and the third cervical vertebra.

Schweiz Rundsch Med Prax 1989 Sep 5;78(36):967-9

A couple who had experienced a whiplash-injury of the neck in the same accident, underwent neurological and neuropsychological examination two years after the trauma. The subjective complaints were very similar: head- and neck pain, vertigo, adynamia, sleep disturbances and severe disturbances of attention, concentration and memory. The neuropsychological examination of the husband demonstrated distinct deficits of attention, concentration and memory. The wife, however, showed positive signs of a neurotic-conversion behaviour. These case reports illustrate both sides of the controversy on the organic versus psychogenic etiology of the cerebral symptoms following whiplash-injury of the neck.

Pediatr Neurol 1998 Nov;19(5):382-4

A 16-year-old female was involved in a jet ski (water craft) accident resulting in bilateral lower extremity fractures but no loss of consciousness or any other evidence of head trauma. Thirty hours later she became comatose. Magnetic resonance imaging was consistent with diffuse axonal injury. She recovered after several weeks without any clinical sequelae. This patient demonstrates an unusual example of diffuse axonal injury without direct head trauma and with delayed onset of symptoms. The authors recommend that patients involved in high-velocity accidents, even without immediate evidence of head injury, be observed for signs of diffuse axonal injury.

Med Clin North Am 1991 May;75(3):641-51

Posttraumatic headache and the postconcussion syndrome.

Goldstein J

Although headache is the most common sequelae of head injury, the posttraumatic headache is associated frequently with dizziness, irritability, lack of concentration, and intolerance to alcohol ingestion as a part of a symptom complex known as the postconcussion syndrome. This article clarifies the definitions of acute traumatic headache, posttraumatic headache, and the postconcussion syndrome and improves diagnostic ability, making the assessment and treatment of patients with these three conditions more accurate and effective.

J Neurotrauma 1997 Oct;14(10):729-38

We studied the acute response of glial fibrillary acidic protein (GFAP) and S100beta gene expression in the cerebral cortex and hippocampus to mild unilateral cortical contusion. Our goal was to evaluate and compare the expression patterns of each gene in the early stages of the astrocytic response to brain injury. RNA was extracted from the cerebral cortex and hippocampus of male rats at 0, 3, 12, 24, or 96 h after lesion or sham-operation, then quantified using an RNase protection assay. Contusion produced a robust elevation in GFAP mRNA by 12 h in both brain regions on the ipsilateral side to the contusion. In the cortex, but not the hippocampus, this elevation was sustained at 96 h. S100beta mRNA levels were elevated bilaterally in lesioned animals at 24 h in both brain regions. However, these data are difficult to interpret because sham mRNA levels decreased with time, making it unclear whether contusion stimulates S100beta gene expression or whether it mitigates the inhibitory effect of sham. We further analyzed the effect of contusion on GFAP and S100beta immunoreactive astrocyte density at 96 h postlesion or postsham by double-label immunocytochemistry. All detectable astrocytes under all conditions were S100beta immunoreactive in both brain regions. Furthermore, all S100beta immunoreactive astrocytes in the lesioned ipsilateral cortex were also GFAP immunoreactive, whereas only about 11% of S100beta positive cells were also GFAP labeled in the contralateral lesioned or the ipsilateral sham cortex. In the hippocampus, all S100beta immunoreactive cells were also GFAP immunoreactive under all conditions. These data correlate with the gene expression data at 96 h, and suggest that, at least in the cortex, resident S100beta-expressing astrocytes produce GFAP at levels that are undetectable by immunocytochemistry until they are activated in response to injury.

Neurosurgery 1999 Sep;45(3):468-75; discussion 475-6

OBJECTIVE: The present study was conducted to validate S-100 protein as a marker of brain damage after minor head injury. METHODS: We studied 50 patients with minor head injuries and Glasgow Coma Scale scores of 13 to 15 in whom computed tomographic scans of the brain revealed no abnormalities. Serum levels of S-100 protein were measured at admittance and hourly thereafter until 12 hours after injury. Magnetic resonance imaging and baseline neuropsychological examinations were performed within 48 hours, and neuropsychological follow-up was conducted at 3 months postinjury. RESULTS: Fourteen patients (28%) had detectable serum levels of S-100 protein (mean peak value, 0.4 microg/L [standard deviation, +/- 0.3]). The S-100 protein levels were highest immediately after the trauma, and they declined each hour thereafter. At 6 hours postinjury, the serum level was below the detection limit (0.2 microg/L) in five (36%) of the patients with initially detectable levels. Magnetic resonance imaging revealed brain contusions in five patients, four of whom demonstrated detectable levels of S-100 protein in serum. The proportion of patients with detectable serum levels was significantly higher when magnetic resonance imaging revealed a brain contusion. In patients with detectable serum levels, we observed a trend toward impaired neuropsychological functioning on measures of attention, memory, and information processing speed. CONCLUSION: Determination of S-100 protein levels in serum provides a valid measure of the presence and severity of traumatic brain damage if performed within the first hours after minor head injury.

J Neurol 1998 Sep;245(9):609-12

Quantification of post-concussion symptoms 3 months after minor head injury in 100 consecutive patients.

Ingebrigtsen T, Waterloo K, Marup-Jensen S, Attner E, Romner B

Post-concussion symptoms (PCS) (such as headaches, irritability, anxiety, dizziness, fatigue and impaired concentration) are frequently experienced by patients who have sustained a minor head injury (MHI). The post-concussion syndrome has been defined as a clinical state where 3 or more symptoms persist for more than 3 months. This report focuses on the quantification of PCS according to the Rivermead Postconcussion Symptoms Questionnaire (RPQ). We studied 100 consecutive patients with MHI and normal computed tomography of the brain. At 3 months after injury, 62% reported the presence of one or more symptoms, and 40% fulfilled the diagnostic criteria for post-concussion syndrome. Patients with post-concussion syndrome had significantly (P < 0.001) higher RPQ scores (mean 19.1, SD 11.9) than those without (mean 1.2, SD 1.8). Patients on sick leave owing to the injury reported significantly (P = 0.05) higher RPQ scores (mean 10.3, SD 13.2) than those not on sick leave (mean 5.5, SD 8.6). We observed no association between age, gender, cause of injury, severity of injury, duration of amnesia and RPQ score. RPQ score provides useful information about the severity of PCS regardless of whether the diagnostic criteria for the post-concussion syndrome are met or not.

Brain Inj 1996 Mar;10(3):159-86

Traumatic brain injury (TBI) refers to a broad range of neurological, cognitive and emotional factors that result from the application of a mechanical force to the head. Mechanical force can be applied on a continuum from none to very severe, and the extent of brain injury is related to the severity of this force. A review of the literature reveals that, while considerable research has been done on minor head injury, there remain several major sources of confusion. First, one of the most noticeable problems relates to the fact that the mild head injury has lower limits which are vaguely defined. This leads to individuals being categorized as having sustained a mild TBI despite minimal or no neurological damage being present. A second source of confusion in the literature is related to the failure to differentiate between cognitive consequences of TBI and post-concussion symptoms (PCS). Since PCS can occur in the absence of head injury, and are often present beyond the period of cognitive recovery from mild TBI, the two clearly result from different factors. Researchers have often failed to separate these two factors when studying recovery of function, and this has led to varying findings on outcome. Finally, many pre-injury factors (age, education, emotional adjustment) and post-injury factors (pain, family support, stress) interact with cognitive functioning and significantly affect recovery from TBI. These problems are reviewed and discussed.

J Clin Exp Neuropsychol 1996 Apr;18(2):265-75

Martin RC, Hayes JS, Gouvier WD

The present study examined the ability of analog malingerers to feign postconcussion symptoms and neuropsychological performance patterns seen in mild head-injured patients. Experimental subjects were randomly assigned to either a control condition, asked to feign deficits consistent with mild head injury without task specific instruction, or feign deficits while given task-specific instruction. A separate group of mild head-injured patients served as a clinical comparison group. Analog malingering groups accurately simulated levels of postconcussive symptoms seen in the mild head-injured patients. However, poorer performance was displayed by the analog malingerers on the objective malingering tests. Coaching did not facilitate realistic patterns of performance for analog malingerers. The results of this study indicate that analog malingerers accurately replicated self-reported postconcussive symptoms, but were less able to simulate objective clinical malingering test performance. These results suggest that self-report measures of postconcussive symptoms and clinical tests are differentially vulnerable to simulation attempts.

Injury 1998 Apr;29(3):199-206

Landy PJ

The objective was to determine why some people who are involved in minor motor vehicle accidents, without loss of consciousness, have persisting headaches and neckache, and to suggest management of these symptoms. Between 1954 and 1994, over 4400 cases were referred for medico-legal opinions. A group has been selected for discussion. During the period 1954-1966, 414 cases following closed head injuries were seen with varying periods of post traumatic amnesia (PTA) from nil to greater than 72 h. The average time between the accident and the examination was 21 months. The shortest period was 3 months and the longest 7 years. The age at the time of the accident varied from 2.5 to 72 years. The largest group fell between the ages of 20 and 40 years. The main complaints were headache, giddiness, loss of concentration and poor memory. 380 were reviewed by questionnaire after settlement of the case. 112 cases of extension/flexion injuries of the neck were seen between 1985 and 1989 and their symptoms and resolution were compared with 50 cases seen over the same period following significant head or neck injury. The results showed that the more severe the head or neck injury, the less likely were the cases to suffer symptoms of post-traumatic headaches or persisting neck symptoms. In conclusion, while 70% of minor head and neck injuries settle within a few weeks of a motor vehicle accident, about 30% continue to complain of headaches and/or neck pain. The prolonged management, extensive physiotherapy and slow court settlement lead to excessive introspection and prolongation of symptoms.

Headache 1996 Jan;36(1):44-7

Repeat CT or MRI of the brain should be considered in posttraumatic headache. We describe two patients with posttraumatic headache who had negative CT scans on initial presentation. One patient later had bilateral subdural hematomas on CT, and the other had temporal lobe hemorrhage on MRI. We recommend considering repeat CT or MRI for persisting posttraumatic headache and mental status change

Semin Clin Neuropsychiatry 1997 Jul;2(3):207-215

This article reviews literature on the prevalence, course, risk factors, and functional impact associated with depression following mild and moderate traumatic brain injury (TBI). Research conducted by the authors on depression in both young and elderly TBI patients is presented, supporting previous findings on the high frequency of affective disturbance and its adverse effects on activities of daily living. Treatment approaches emphasizing early patient education and counseling are discussed as potential strategies to mitigate the development of posttraumatic depression.

Curr Opin Neurol 1993 Dec;6(6):841-6

Progress in research includes studies concerning the pathophysiology and outcome of pediatric head injury, the pathology of the hippocampus in fatal injury, and the use of multivariate statistics to predict outcome in survivors. Recent research has confirmed and extended findings regarding the differential effects of closed head injury, depending on the age of the individual. These studies indicate that the consequences of head injury are more severe in older adults and in children younger than 2 years. Neuroimaging findings include evidence for delayed brain injury as a major cause of mortality and disability. Functional brain imaging provides evidence for cerebral dysfunction that is not appreciated by structural brain imaging techniques and may have a stronger relationship to neurobehavioral sequelae. The neurobehavioral sequelae frequently implicate frontal dysfunction, even in the absence of structural findings on computed tomography or magnetic resonance imaging. Studies of mild head injury have expanded our knowledge concerning the pathogenesis of postconcussional symptoms, including a preinjury vulnerability based on recent life events. Persistent postconcussional symptoms after mild head injury are frequently associated with emotional disturbance of clinical proportions.

J Neurol Neurosurg Psychiatry 1992 Apr;55(4):255-62

Fifty patients who sustained mild to moderate closed head injury (CHI) underwent a CT scan, MRI, and neurobehavioural testing. At baseline 40 patients had intracranial hyperintensities detected by MRI which predominated in the frontal and temporal regions, whereas 10 patients had lesions detected by CT. Neurobehavioural data obtained during the first admission to hospital disclosed no distinctive pattern in subgroups of patients characterised by lesions confined to the frontal, temporal, or frontotemporal regions, whereas all three groups exhibited pervasive deficits in relation to normal control subjects. The size of extraparenchymal lesion was significantly related to the initial Glasgow Coma Scale score, whereas this relation was not present in parenchymal lesions. One and three month follow up MRI findings showed substantial resolution of lesion while neuropsychological data reflected impressive recovery. The follow up data disclosed a trend from pervasive deficits to more specific impairments which were inconsistently related to the site of brain lesion. These results corroborate and extend previous findings, indicating that intracranial lesions detected by MRI are present in most patients hospitalised after mild to moderate CHI. Individual differences in the relation between site of lesion and the pattern of neuropsychological findings, which persist over one to three months after mild to moderate CHI, remain unexplained.

AJNR Am J Neuroradiol 1999 May;20(5):857-66

BACKGROUND AND PURPOSE: Patients with mild traumatic brain injury (TBI) often show significant neuropsychological dysfunction despite the absence of abnormalities on traditional neuroradiologic examinations or EEG. Our objective was to determine if magnetic source imaging (MSI), using a combination of MR imaging and magnetoencephalography (MEG), is more sensitive than EEG and MR imaging in providing objective evidence of minor brain injury. METHODS: Four subject groups were evaluated with MR, MSI, and EEG. Group A consisted of 20 neurologically normal control subjects without histories of head trauma. Group B consisted of 10 subjects with histories of mild head trauma but complete recovery. Group C consisted of 20 subjects with histories of mild head injury and persistent postconcussive symptoms. The 15 subjects included in group D underwent repeat examinations at an interval of 2 to 4 months. RESULTS: No MR abnormalities were seen in the normal control group or the asymptomatic group, but five (20%) of the patients with persistent postconcussive symptoms had abnormal MR findings. EEG was abnormal for one subject (5%) from the normal control group, one (10%) from the asymptomatic group, and five (20%) from the group with persistent postconcussive symptoms. MSI was abnormal for one subject (5%) from the normal control group, one (10%) from the asymptomatic group, and 13 (65%) from the group with persistent postconcussive symptoms. There was a direct correlation between symptom resolution and MSI findings for the symptomatic head trauma group. CONCLUSION: MSI indicated brain dysfunction in significantly more patients with postconcussive symptoms than either EEG or MR imaging (P < .01). The presence of excessive abnormal low-frequency magnetic activity provides objective evidence of brain injury in patients with postconcussive syndromes and correlates well with the degree of symptomatic recovery.

Arch Phys Med Rehabil 1997 Dec;78(12):1316-20

OBJECTIVE: To assess which social activities were still impaired 5 years after a traumatic brain injury (TBI) in adults, and which neuropsychological impairments were associated with this loss of social autonomy. DESIGN: Cross-sectional study of 79 patients selected from the follow-up cohort of an epidemiologic survey of 2,116 TBI patients. SETTING: The present study was of ambulatory patients seen at hospital or at their homes. The inception cohort was from the trauma center of a university hospital and from a general hospital that is representative of level II trauma centers in Aquitaine, France. PATIENTS: Seventy-nine patients selected from a representative sample of 407 patients who were included in the 5-year follow-up study of the initial cohort (convenience sample). MAIN OUTCOME MEASURES: Glasgow Outcome Scale (GOS) and loss of social autonomy as assessed by the European Brain Injury Society's European Head Injury Evaluation Chart; assessment of neurobehavioral impairments by means of the Neurobehavioral Rating Scale-Revised. RESULTS: Up to 16 patients suffered disability for at least one social skill because of cognitive/behavioral reasons. Seven needed full-time supervision. Performing administrative tasks and financial management, writing letters and calculating, driving, planning the week, and using public transport were the most impaired social abilities. Loss of social autonomy was mainly observed in severely injured patients. Univariate analysis showed that mental fatigability, motor slowing, memory difficulties, and disorders of executive function were associated with low scores on the GOS, unemployment, and difficulties in shopping, using public transport, and performing financial management and administrative tasks. CONCLUSION: Persistent impairments of executive functions and speed of psychomotor processing are major factors associated with loss of social autonomy and inability to return to work long after TBI in adults. Improving these impairments in concrete social situations represents a major challenge for cognitive rehabilitation.

Neurol India 1999 Mar;47(1):32-9

Remediation of attention deficits in head injury.

Nag S, Rao SL

Head injury is associated with psychological sequelae which impair the patient's psychosocial functioning. Information processing, attention and memory deficits are seen in head injuries of all severity. We attempted to improve deficits of focused, sustained and divided attention. The principle of overlapping sources of attention resource pools was utilised in devising the remediation programme. Tasks used simple inexpensive materials. Four head injured young adult males with post concussion syndrome underwent the retraining program for one month. The patients had deficits of focused, sustained and divided attention parallel processing, serial processing, visual scanning, verbal learning and memory and working memory. After the retraining programme the deficits of attention improved in the four patients. Serial processing improved in two patients. Parallel processing and neuropsychological deficits did not improve in any patient. The symptom intensity reduced markedly and behavioural functioning improved in three of the four patients. The results supported an association between improving attention and reduction of symptom intensity. Attention remediation shows promise as a cost effective, time efficient and simple technique to improve the psychological and psychosocial functioning of the head injured patient.

J Neurol Neurosurg Psychiatry 1997 Sep;63(3):368-72

Whiplash associated disorders are a medicolegally controversial condition becoming increasingly worrisome in the western world. This study was designed to evaluate perfusion and glucose metabolism in whiplash brain. Using Tc-99m-bicisate (ECD) single photon emission computed tomography (SPECT) and F-18-fluorodeoxyglucose (FDG) PET, six clinically and neuropsychologically controlled patients (patient group) with whiplash syndrome and 12 normal controls (control group) were investigated. Standardised elliptical regions of interest (ROIs) were determined in three adjacent transaxial slices in the frontal, parietal, temporal, and parieto-occipital cortex, cerebellum, brain stem, basal ganglia, and thalamus. For PET, the glucose metabolic index (GMI; =ROI uptake/global uptake at the level of the basal ganglia) and, for SPECT, the perfusion index (PI; =ROI/global) were calculated. In the patient group there was significant hypometabolism and hypoperfusion in the parieto-occipital regions (on the right (R) and left (L) side) compared with the control group: PET data: GMI parieto-occipital R: control 1.066 (0.081) (mean (SD)), patient 0.946 (0.065); P=0.0092, Mann Whitney. GMI parieto-occipital L: control 1.034 (0.051), patient 0.922 (0.073); p=0.0067. SPECT data: PI parieto-occipital R: control 1.262 (0.066), patient 1.102 (0.063); P=0.0039. PI parieto-occipital L: control 1.226 (0.095), patient 1.098 (0.075); P=0.0273. In some patients there was hypometabolism (>2 SD of control) in regions other than the parieto-occipital region. It is hypothesised that parieto-occipital hypometabolism may be caused by activation of nociceptive afferent nerves from the upper cervical spine.

Schweiz Rundsch Med Prax 1996 Sep 3;85(36):1087-90

In any grade of distortion of the cervical spine as a result of acceleration forces in addition to cervical symptoms cerebral symptoms like headache, vertigo, auditory disturbances, tinnitus, disturbances in concentration and memory, difficulties in swallowing, impaired vision and temporo-mandibular dysfunctions may appear. These symptoms can persist and become invalidating. Cerebral single-photon emission tomography (SPECT) and positron emission tomography (PET) enable new diagnostic horizons for neurotraumatology. In this article we summarize the actual findings of these nuclear medical methods in neuropsychologically deficient patients with distortion of the cervical spine as a result of acceleration forces. Especially the latest results of the group of Basle (University Hospital Basle, Clinic of Rehabilitation Rheinfelden, Switzerland) are illustrated. This group found parieto-occipital hypoperfusion by relative quantitation using SPECT and bicisate (Neurolite, ECD). A first pilot study using PET and F-18-fluoro-deoxyglucose (FDG) could verify the above observation. The group's working hypothesis is that parieto-occipital hypoperfusion may be caused by activation of nociceptive afferences from the upper cervical spine. A critical approach to interpreting new functional methods and, on the other hand, openness in new scientific findings may contribute to answering the lasting controversial medico-legal discussion with more objectivity.

J Neuropsychiatry Clin Neurosci 1994 Summer;6(3):229-36

Posttraumatic headache.

Packard RC, Ham LP

The authors review posttraumatic headache (PTH). The most common symptom following head injury, PTH is paradoxically most severe after mild head injury. Although most cases resolve within 6 to 12 months, many patients have protracted or even permanent headache. Because PTH generally has no objective findings, it is often controversial whether the symptom is "real," "psychogenic," or "fabricated." Despite persisting beliefs by physicians, attorneys, and insurers that PTH resolves upon legal settlement, recent studies have shown that "permanent" PTH is usually still present several years after a legal settlement. Often PTH affects family life, recreation, and employment. Patients require education and support as well as appropriate evaluation and treatment.

J Trauma 1998 Oct;45(4):765-7

BACKGROUND: S-100, a protein of astroglial cells, is described as a marker for central nervous system damage. The aim of this study was to evaluate whether the marker could give information about the severity and possibility of functional recovery after minor and severe head injury. METHODS: Thirty patients after severe head injury (Glasgow Coma Scale score < 9) and 11 patients after minor head injury (Glasgow Coma Scale score > 12) were included. In each case, blood samples were drawn within 6 hours after injury. Outcome was estimated at hospital discharge using the Glasgow Outcome Scale. RESULTS: All patients who sustained minor head injury had reached a favorable outcome by the time they were discharged from the hospital. Their mean S-100 serum level was 0.35 microg/L. Patients who sustained severe head injury and were classified as having an unfavorable outcome (31%) showed a mean serum concentration of 4.9 microg/L, whereas patients classified as having a favorable outcome (69%) had a mean S-100 level of 1.2 microg/L. All groups differed significantly (p < 0.05). CONCLUSION: S-100 appears to be a promising marker for the severity of head injury and neuronal damage.

J Clin Exp Neuropsychol 1999 Oct;21(5):620-8

Persistent Post-Concussive Syndrome: A proposed methodology and literature review to determine the effects, if any, of mild head and other bodily injury.

Satz PS, Alfano MS, Light RF, Morgenstern HF, Zaucha KF, Asarnow RF, Newton S

Following mild head injury, a subgroup of individuals exhibit a constellation of chronic symptoms, a condition Alexander (1995) labeled Persistent Post-Concussive Syndrome (PPCS). He implicated neurological factors in the initial phase of the syndrome but psychological factors in the maintenance of symptoms. However, it is unclear as to whether an initial mild head injury is necessary or sufficient to cause the symptoms of PPCS. We first outline a study design comparing a mild closed-head injury group to both a normal and an other injury control group to answer this question. Next, we review the literature since 1960 to determine the findings of any studies using this design. The results of the literature review indicate that few such studies exist. To date, those that have been done suggest that there is no strong evidence for a specific effect for mild head injury on cognitive functioning. We discuss directions for future research given these findings.

Brain Inj 1998 Jul;12(7):537-53

The present study investigated the prevalence and magnitude of depressive symptomatology in a sample of patients who had sustained traumatic brain injury (TBI) six months earlier. Depression was examined as a function of recovery outcome status, and its association with neuropsychological functioning, personal competency, and employability was also explored. Subjects were 100 patients who had previously sustained moderate-to-severe TBI who were enrolled as research subjects in the UCLA Brain Injury Research Center, and 30 matched control subjects who had sustained traumatic injuries other than to the head six months prior to evaluation. The results showed a significant association between depression and recovery status as measured by the Glasgow Outcome Scale (GOS). A significant majority of depressed subjects were found in the poorer GOS outcome groups (severe and moderate disability), compared to TBI subjects who had good GOS outcomes, and control subjects. This association was also reflected in the magnitude of the mean depression scores on two self-report measures of depression. However, no association was found between depression status and performance on the neuropsychological measures. Effects of depression were found only on an examiner-rated Patient Competency scale, and a metacognition measure based on self-report. These results are discussed in terms of brain injury severity, recovery status, and metacognition issues in TBI and other disorders.

Brain Inj 1999 Sep;13(9):705-14

Panic disorder in a patient with traumatic brain injury: a case report and discussion.

Scheutzow MH, Wiercisiewski DR

Individuals that may be especially susceptible to panic attacks in the rehabilitation setting are patients who have suffered traumatic brain injuries, post-concussion syndrome, lesions, or encephalopathy. An individual is described who suffered a traumatic brain injury and was determined to have suffered a panic attack during his rehabilitation stay. The manifestations of panic attacks are described, using the case report as an example. The psychological aetiology of panic disorders is also reviewed, and treatment options using four major classes of neuropharmacologic agents: benzodiazepines, tricyclic antidepressants, monoamide oxidase inhibitors, and serotonin reuptake inhibitors, are discussed. Given the increasing incidence and survival of patients with traumatic brain injuries, the complications of panic attacks and disorders will become more important; they are a serious condition that can affect an individual's lifestyle, employment, and relationships, and increase the risk of suicide. Rehabilitation specialists should be aware of the manifestations and management of panic attacks and come to appreciate that recognition of this treatable condition is important during all stages of rehabilitation.

Scott Med J 1997 Apr;42(2):40-3

Results are reported from a study to identify patients residing in Fife with mild traumatic brain injury in the 16-65 year old age group, who attended an accident and emergency department following their brain injury. Over a two month period 161 such patients attended with minor head trauma, of which 33 entered our study. The major cause of mild traumatic brain injury was assault. We found that over two-thirds of patients in the study had persisting post-concussive symptoms six months post injury. Neuropsychological testing showed problems of concentration and memory, but not at a level that was significantly different from that expected in an average population. Other studies have shown that symptom rates are higher when patients get no explanation of their symptoms and we feel that better co-ordination of services for brain injured patients in Fife is required, to provide the necessary information, education and support.

Neurosurgery 1985 Jul;17(1):41-7

This study demonstrates residual mental deficits in patients who have apparently recovered after closed head injury. Twenty closed head injury patients were compared to 20 normal control subjects matched for age, sex, handedness, education, language, and IQ. All received a series of neuropsychological tests. Discriminant function analysis significantly differentiated the two groups. Correct classification of individuals as having suffered a head injury or not was 85%. The head injury patients did have primary impairment on tests of divided attention. Litigation was not a factor. We propose that this impairment of information processing reflects residual brain damage secondary to the closed head injury.

Am J Sports Med 1989 Jul-Aug;17(4):573-8

Sixty-nine football players from six Norwegian First Division League Clubs underwent a neurologic and EEG examination to investigate the incidence of head injuries. A significantly increased incidence of EEG disturbances were found in the football players compared to matched controls. The disturbances were most pronounced among the youngest players. The higher incidence of EEG disturbances found in the football players is most likely due to neuronal damage caused by repeated minor head traumas.

Acta Neurol Scand 1989 Aug;80(2):151-6

Thirty-seven former football players of the Norwegian national team underwent a neurological and electroencephalographic (EEG) examination to investigate the incidence of head injuries due to heading the ball. Sixteen players complained of protracted and permanent symptoms commonly attributed to the post-concussional syndrome: headache, irritability, dizziness, lack of concentration and impaired memory. A significantly increased incidence of EEG abnormalities was found in players compared with matched controls. The high incidence of EEG changes is probably the result of a cumulative effect due to repeated head traumas.

Sports Med 1992 Sep;14(3):200-13

Head injuries have been shown to account for between 4 and 22% of soccer injuries. Clinical and neuropsychological investigations of patients with minor head trauma have revealed organic brain damage. 69 active football (soccer) players and 37 former players of the Norwegian national team were included in a neurological and electroencephalographic (EEG) study to investigate the incidence of head injuries mainly caused by heading the ball. 3% of the active and 30% of the former players complained of permanent problems such as headache, dizziness, irritability, impaired memory and neck pain. 35% of the active and 32% of former players had from slightly abnormal to abnormal EEG compared with 13 and 11% of matched controls, respectively. There were fewer definitely abnormal EEG changes among typical 'headers' (10%) than among 'nonheaders' (27%). The former players were also subjected to cerebral computed tomography (CT), a neuropsychological examination and a radiological examination of the cervical spine. One-third of the players were found to have central cerebral atrophy and 81% to have from mild to severe (mostly mild to moderate) neuropsychological impairment. The radiological examination of the cervical spine revealed a significantly higher incidence and degree of degenerative changes than in a matched control group.

Acta Neurochir (Wien) 1997;139(1):26-31; discussion 31-2

Protein S-100 is a calcium binding protein, synthetized in astroglial cells in all parts of the central nervous system (CNS). We have previously reported high serum levels of protein S-100 in patients after minor head injury (MHI). A battery of conventional and computerized neuropsychological measures was administered to two groups of MHI patients. Neuropsychological outcome at 12 months postinjury was examined in a group of 7 patients with increased serum levels of protein S-100 after MHI and 7 age- and sex-matched controls without detectable S-100 in serum after MHI. Our results demonstrate no overall cognitive dysfunction in either of the two groups. Our findings indicate specific dysfunction on measures of reaction time, attention and speed of information processing for the S-100 group. Posttraumatic depression does not explain the neuropsychological differences between the groups. These findings support that increased serum levels of protein S-100 may be of predictive and prognostic value for longlasting neurocognitive abnormalities after minor head injury. Presence of S-100 in serum may indicate the presence of diffuse brain damage. Our results suggest that information processing measures in computerized neuropsychological assessment are more sensitive for detecting small signs of neurocognitive abnormalities after MHI than conventional test batteries.

J Head Trauma Rehabil 1999 Aug;14(4):337-50

OBJECTIVE: To examine the incidence and neuropsychological, behavioral, and neuroimaging correlates of postconcussive symptoms (PCS) in children with mild closed head injuries (CHI). DESIGN: 26 Children with mild CHI and 8 of their uninjured siblings, from 8 to 15 years old, were recruited prospectively and assessed at baseline (ie, within 7 days of injury) and at 3 months postinjury. Parents rated PCS, motivation and affective lability, and behavioral adjustment. Baseline ratings assessed premorbid functioning retrospectively, and follow-up ratings assessed postinjury status. On both occasions, children completed neuropsychological testing, and those with mild CHI also underwent magnetic resonance imaging (MRI). RESULTS: Children with mild CHI did not differ from siblings in baseline ratings of premorbid PCS but displayed higher ratings on several PCS at 3 months postinjury. Thirty-five percent of children with mild CHI showed increases in PCS, compared with baseline premorbid ratings, but none of the siblings did so. Children with mild CHI whose PCS increased from premorbid levels showed poorer neuropsychological functioning at baseline than did children whose PCS did not increase, although the differences had partially resolved by 3 months. They also displayed decreased motivation over time. Their behavioral adjustment was poorer and they had smaller white matter volumes on MRI, but the latter differences were present at baseline and did not change over time, suggesting that they existed prior to the injury. CONCLUSION: Postinjury increases in PCS occur in a sizable minority of children with mild CHI and more often than among uninjured siblings. Increases in PCS following mild CHI are associated with premorbid neurological and psychosocial vulnerability, but also with postinjury decrements in neuropsychological and neurobehavioral functioning