Novel Oppositional Defiant Disorder or Conduct Disorder 24 Months After Traumatic Brain Injury in Children and Adolescents.

OBJECTIVE: The authors sought to identify predictive factors of new-onset or novel oppositional defiant disorder or conduct disorder assessed 24 months after traumatic brain injury (TBI). METHODS: Children ages 5 to 14 years who had experienced TBI were recruited from consecutive hospital admissions. Soon after injury, participants were assessed for preinjury characteristics, including psychiatric disorders, socioeconomic status (SES), psychosocial adversity, and family function, and the presence and location of lesions were documented by MRI. Psychiatric outcomes, including novel oppositional defiant disorder or conduct disorder, were assessed 24 months after injury. RESULTS: Of the children without preinjury oppositional defiant disorder, conduct disorder, or disruptive behavior disorder not otherwise specified who were recruited in this study, 165 were included in this sample; 95 of these children returned for the 24-month assessment. Multiple imputation was used to address attrition. The prevalence of novel oppositional defiant disorder or conduct disorder was 23.7 out of 165 (14%). In univariable analyses, novel oppositional defiant disorder or conduct disorder was significantly associated with psychosocial adversity (p=0.049) and frontal white matter lesions (p=0.016) and was marginally but not significantly associated with SES. In the final multipredictor model, frontal white matter lesions were significantly associated with novel oppositional defiant disorder or conduct disorder (p=0.021), and psychosocial adversity score was marginally but not significantly associated with the outcome. The odds ratio of novel oppositional defiant disorder or conduct disorder among the children with versus those without novel depressive disorder was significantly higher for girls than boys (p=0.025), and the odds ratio of novel oppositional defiant disorder or conduct disorder among the children with versus those without novel attention-deficit hyperactivity disorder (ADHD) was significantly higher for boys than girls (p=0.006). CONCLUSION: Approximately 14% of children with TBI developed oppositional defiant disorder or conduct disorder. The risk for novel oppositional defiant disorder or conduct disorder can be understood from a biopsychosocial perspective. Sex differences were evident for comorbid novel depressive disorder and comorbid novel ADHD.

Novel Psychiatric Disorder 6 Months After Traumatic Brain Injury in Children and Adolescents.

OBJECTIVE: To investigate the factors predictive of novel psychiatric disorders in the interval 0-6 months following traumatic brain injury (TBI). METHODS: Children ages 5-14 years consecutively hospitalized for mild to severe TBI at five hospitals were recruited. Participants were evaluated at baseline (soon after injury) for pre-injury characteristics including psychiatric disorders, socioeconomic status (SES), psychosocial adversity, family function, family psychiatric history, and adaptive function. In addition to the psychosocial variables, injury severity and lesion location detected with acquisition of a research MRI were measured to develop a biopsychosocial predictive model for development of novel psychiatric disorders. Psychiatric outcome, including occurrence of a novel psychiatric disorder, was assessed 6 months after the injury. RESULTS: The recruited sample numbered 177 children, and 141 children (80%) returned for the six-month assessment. Of the 141 children, 58 (41%) developed a novel psychiatric disorder. In univariable analyses, novel psychiatric disorder was significantly associated with lower SES, higher psychosocial adversity, and lesions in frontal lobe locations, such as frontal white matter, superior frontal gyrus, inferior frontal gyrus, and orbital gyrus. Multivariable analyses found that novel psychiatric disorder was independently and significantly associated with frontal-lobe white matter, superior frontal gyrus, and orbital gyrus lesions. CONCLUSION: The results demonstrate that occurrence of novel psychiatric disorders following pediatric TBI requiring hospitalization is common and has identifiable psychosocial and specific biological predictors. However, only the lesion predictors were independently related to this adverse psychiatric outcome.

Traumatic Brain Injury in Children and Adolescents: Psychiatric Disorders 24 Years Later.

OBJECTIVE: The investigators aimed to extend findings regarding predictive factors of psychiatric outcomes among children and adolescents with traumatic brain injury (TBI) from 2 to 24 years postinjury. METHODS: Youths aged 6-14 years who were hospitalized following TBI from 1992 to 1994 were assessed at baseline for TBI severity and for preinjury psychiatric, adaptive, and behavioral functioning; family functioning; family psychiatric history; socioeconomic status; and intelligence within weeks of injury. Predictors of psychiatric outcomes following pediatric TBI at 3, 6, 12, and 24 months postinjury have previously been reported. In this study, repeat psychiatric assessments were completed at 24 years postinjury with the same cohort, now adults aged 29-39 years, with the outcome measure being presence of a psychiatric disorder not present before the TBI ("novel psychiatric disorder"). RESULTS: Fifty participants with pediatric TBI were initially enrolled, and the long-term outcome analyses focused on data from 45 individuals. Novel psychiatric disorder was present in 24 out of 45 (53%) participants. Presence of a current novel psychiatric disorder was independently predicted by the presence of a preinjury lifetime psychiatric disorder and by severity of TBI. CONCLUSIONS: Long-term psychiatric outcome (mean=23.92 years [SD=2.17]) in children and adolescents hospitalized for TBI can be predicted at the point of the initial hospitalization encounter by the presence of a preinjury psychiatric disorder and by greater injury severity.

Novel Oppositional Defiant Disorder 12 Months After Traumatic Brain Injury in Children and Adolescents.

OBJECTIVE: The investigators examined the factors predictive of novel oppositional defiant disorder in the 6-12 months following traumatic brain injury (TBI). METHODS: Children ages 5-14 years old who experienced a TBI were recruited from consecutive admissions to five hospitals. Participants were evaluated soon after injury (baseline) for preinjury characteristics, including psychiatric disorders, adaptive function, family function, psychosocial adversity, family psychiatric history, socioeconomic status, and injury severity, to develop a biopsychosocial predictive model for development of novel oppositional defiant disorder. MRI analyses were conducted to examine potential brain lesions. Psychiatric outcome, including that of novel oppositional defiant disorder, was assessed 12 months after injury. RESULTS: Although 177 children were recruited for the study, 120 children without preinjury oppositional defiant disorder, conduct disorder, or disruptive behavior disorder not otherwise specified (DBD NOS) returned for the 12-month assessment. Of these 120 children, seven (5.8%) exhibited novel oppositional defiant disorder, and none developed conduct disorder or DBD NOS in the 6-12 months postinjury. Novel oppositional defiant disorder was significantly associated with lower socioeconomic status, higher psychosocial adversity, and lower preinjury adaptive functioning. CONCLUSIONS: These results demonstrate that novel oppositional defiant disorder following TBI selectively and negatively affects an identifiable group of children. Both proximal (preinjury adaptive function) and distal (socioeconomic status and psychosocial adversity) psychosocial variables significantly increase risk for this outcome.

Novel Oppositional Defiant Disorder 6 Months After Traumatic Brain Injury in Children and Adolescents.

OBJECTIVE: The investigators aimed to assess predictive factors of novel oppositional defiant disorder (ODD) among children and adolescents in the first 6 months following traumatic brain injury (TBI). METHODS: Children ages 5-14 years who experienced a TBI were recruited from consecutive admissions to five hospitals. Testing of a biopsychosocial model that may elucidate the development of novel ODD included assessment soon after injury (baseline) of preinjury characteristics, including psychiatric disorders, adaptive function, family function, psychosocial adversity, family psychiatric history, socioeconomic status, injury severity, and postinjury processing speed (which may be a proxy for brain injury). MRI analyses were also conducted to examine potential brain lesions. Psychiatric outcome, including that of novel ODD, was assessed 6 months after the injury. RESULTS: A total of 177 children and adolescents were recruited for the study, and 134 who were without preinjury ODD, conduct disorder, or disruptive behavior disorder not otherwise specified (DBD NOS) returned for the 6-month assessment. Of those who returned 6 months postinjury, 11 (8.2%) developed novel ODD, and none developed novel conduct disorder or DBD NOS. Novel ODD was significantly associated with socioeconomic status, preinjury family functioning, psychosocial adversity, and processing speed. CONCLUSIONS: These findings show that an important minority of children with TBI developed ODD. Psychosocial and injury-related variables, including socioeconomic status, lower family function, psychosocial adversity, and processing speed, significantly increase risk for this outcome.

Inferior rectus displacement in heavy eye syndrome and sagging eye syndrome.

PURPOSE: To evaluate if there is a nasal displacement of the vertical rectus muscles in heavy eye syndrome (HES) and/or sagging eye syndrome (SES) compared with age-matched controls. METHODS: We reviewed the charts of all patients with the diagnosis of HES or SES who were seen at the University of California San Diego (UCSD) between the years 2008-2016 who underwent magnetic resonance imaging (MRI) of the brain and orbits. The control group included patients who had brain and orbital MRIs at UCSD in the absence of known pathology in the orbits or globes. Measurements were taken by 3 separate examiners for all groups. RESULTS: Twenty-four patients (16 with SES and 8 with HES) and 24 age-matched controls were retrospectively reviewed. The superior rectus (SR) of patients with HES and SES was more nasally displaced from the midline compared with that of age-matched controls (p = 0.04, p = 0.03, respectively). The inferior rectus (IR) of patients with HES but not with SES was more nasally displaced from the midline compared with that of age-matched controls (p = 0.04, p = 0.62, respectively). In all groups, the IR nasal displacement from the midline was approximately double compared with the SR. CONCLUSIONS: There is a significant nasal displacement of the SR in HES and SES and IR in HES. The observed IR nasal displacement in HES is a new finding and may explain the residual hypotropia and/or esotropia following surgical interventions for HES not involving the IR.

Cervical spinal canal narrowing in idiopathic syringomyelia.

INTRODUCTION: The cervical spine in Chiari I patient with syringomyelia has significantly different anteroposterior diameters than it does in Chiari I patients without syringomyelia. We tested the hypothesis that patients with idiopathic syringomyelia (IS) also have abnormal cervical spinal canal diameters. The finding in both groups may relate to the pathogenesis of syringomyelia. METHODS: Local institutional review boards approved this retrospective study. Patients with IS were compared to age-matched controls with normal sagittal spine MR. All subjects had T1-weighted spin-echo (500/20) and T2-weighted fast spin-echo (2000/90) sagittal cervical spine images at 1.5 T. Readers blinded to demographic data and study hypothesis measured anteroposterior diameters at each cervical level. The spinal canal diameters were compared with a Mann-Whitney U test. The overall difference was assessed with a Friedman test. Seventeen subjects were read by two reviewers to assess inter-rater reliability. RESULTS: Fifty IS patients with 50 age-matched controls were studied. IS subjects had one or more syrinxes varying from 1 to 19 spinal segments. Spinal canal diameters narrowed from C1 to C3 and then enlarged from C5 to C7 in both groups. Diameters from C2 to C4 were narrower in the IS group (p < 0.005) than in controls. The ratio of the C3 to the C7 diameters was also smaller (p = 0.004) in IS than controls. Collectively, the spinal canal diameters in the IS were significantly different from controls (Friedman test p < 0.0001). CONCLUSION: Patients with IS have abnormally narrow upper and mid cervical spinal canal diameters and greater positive tapering between C3 and C7.

Head computed tomography in the emergency department: a collection of easily missed findings that are life-threatening or life-changing.

BACKGROUND: The use of noncontrast head computed tomography (CT) has become commonplace in the emergency department (ED) as a means of screening for a wide variety of pathologies. Approximately 1 in 14 ED patients receives a head CT scan, and analyzing and interpreting this high volume of images in a timely manner is a daily challenge. OBJECTIVES: Minimizing interpretation error is of paramount importance in the context of life-threatening and time-sensitive diagnoses. Therefore, it is prudent for the physician to recognize particular pitfalls in head CT interpretation and establish search patterns and practices that minimize such errors. In this article, we discuss a collection of common ED cases with easily missed findings, and identify time-effective practices and patterns to minimize interpretation error. DISCUSSION: There are numerous reasons for false-negative interpretations, including, but not limited to, incomplete or misleading clinical history, failure to review prior studies, suboptimal windowing and leveling, and failure to utilize multiple anatomic views via multi-planar reconstructions and scout views. We illustrate this in four specific clinical scenarios: stroke, trauma, headache, and altered mental status. CONCLUSION: Accurate and timely interpretation in the emergent setting is a daily challenge for emergency physicians. Knowledge of easily overlooked yet critical findings is a first step in minimizing interpretation error.

Intracranial causes of ophthalmoplegia: the visual reflex pathways.

The gathering of visual information is a complex process that relies on concerted movements of the eyes, and cranial nerves II-VIII are at least partially involved in the visual system. The cranial nerves do not function in isolation, however, and there are multiple higher-order cortical centers that have input into the cranial nerves to coordinate eye movement. Among the functions of the cortical reflex pathways are (a) controlling vertical and horizontal gaze in response to vestibular input to keep the eyes focused on an object as the head moves through space, and (b) controlling rapid, coordinated eye movement to a new visual target (saccades). There are also reflex pathways connecting the cranial nerves involved in vision that produce consensual blinking of the eyes in response to corneal stimulation of one eye and consensual pupillary constriction in response to light input on one pupil. A variety of intracranial pathologic conditions, including benign and malignant neoplasms, infection, trauma, autoimmune diseases, vascular anomalies, degenerative diseases, and inherited-congenital disorders, can disrupt the cranial nerves and visual reflex pathways. This disruption can manifest in myriad ways-for example, as extraocular muscle paresis, afferent pupillary defect, oculosympathetic paresis (Horner syndrome), internuclear ophthalmoplegia, dorsal midbrain (Parinaud) syndrome, or loss of the corneal reflex. Knowledge of the function and anatomy of the cranial nerves and visual reflex pathways, coupled with selection of the proper magnetic resonance pulse sequence, will allow the radiologist to order appropriate imaging of the involved cranial nerve or visual reflex pathway based on the patient's symptoms and thereby play an essential role in establishing the diagnosis and planning appropriate therapy.

Assessing Pediatric Mild Traumatic Brain Injury and Its Recovery Using Resting-State Magnetoencephalography Source Magnitude Imaging and Machine Learning.

The objectives of this machine-learning (ML) resting-state magnetoencephalography (rs-MEG) study involving children with mild traumatic brain injury (mTBI) and orthopedic injury (OI) controls were to define a neural injury signature of mTBI and to delineate the pattern(s) of neural injury that determine behavioral recovery. Children ages 8-15 years with mTBI (n = 59) and OI (n = 39) from consecutive admissions to an emergency department were studied prospectively for parent-rated post-concussion symptoms (PCS) at: 1) baseline (average of 3 weeks post-injury) to measure pre-injury symptoms and also concurrent symptoms; and 2) at 3-months post-injury. rs-MEG was conducted at the baseline assessment. The ML algorithm predicted cases of mTBI versus OI with sensitivity of 95.5 ± 1.6% and specificity of 90.2 ± 2.7% at 3-weeks post-injury for the combined delta-gamma frequencies. The sensitivity and specificity were significantly better (p < 0.0001) for the combined delta-gamma frequencies compared with the delta-only and gamma-only frequencies. There were also spatial differences in rs-MEG activity between mTBI and OI groups in both delta and gamma bands in frontal and temporal lobe, as well as more widespread differences in the brain. The ML algorithm accounted for 84.5% of the variance in predicting recovery measured by PCS changes between 3 weeks and 3 months post-injury in the mTBI group, and this was significantly lower (p < 10-4) in the OI group (65.6%). Frontal lobe pole (higher) gamma activity was significantly (p < 0.001) associated with (worse) PCS recovery exclusively in the mTBI group. These findings demonstrate a neural injury signature of pediatric mTBI and patterns of mTBI-induced neural injury related to behavioral recovery.

Long-Term Psychiatric Outcomes in Adults with History of Pediatric Traumatic Brain Injury.

The objective of the study was to compare psychiatric outcomes in adults with and without history of pediatric traumatic brain injury (TBI). Youth ages 6 to 14 years hospitalized for TBI from 1992 to 1994 were assessed at baseline and at 3, 6, 12, and 24 months post-injury. In the current study, psychiatric assessments were repeated at 24 years post-injury with the same cohort, now adults ages 29 to 39 years. A control group of healthy adults also was recruited for one-time cross-sectional assessments. Outcome measures included: 1) presence of a psychiatric disorder since the 24-month assessment not present before the TBI ("novel psychiatric disorder," NPD), or in the control group, the presence of a psychiatric disorder that developed after the mean age of injury of the TBI group plus 2 years; and 2) Time-to-Event for onset of an NPD during the same time periods. In the TBI group, NPDs were significantly more common, and presence of a current NPD was significantly predicted by presence of a pre-injury lifetime psychiatric disorder and by abnormal day-of-injury computed tomography (CT) scan. Compared with controls, the TBI group also had significantly shorter Time-to-Event for onset of any NPD. These findings demonstrate that long-term psychiatric outcomes in adults previously hospitalized for pediatric TBI are significantly worse when compared with adult controls without history of pediatric TBI, both in terms of prevalence and earlier onset of NPD. Further, in the TBI group, long-term NPD outcome is predicted independently by presence of pre-injury psychiatric disorder and abnormal day-of-injury CT scan.

Resting-State Magnetoencephalography Source Imaging Pilot Study in Children with Mild Traumatic Brain Injury.

Mild traumatic brain injury (mTBI) accounts for the vast majority of all pediatric TBI. An important minority of children who have suffered an mTBI have enduring cognitive and emotional symptoms. However, the mechanisms of chronic symptoms in children with pediatric mTBI are not fully understood. This is in part due to the limited sensitivity of conventional neuroimaging technologies. The present study examined resting-state magnetoencephalography (rs-MEG) source images in 12 children who had mTBI and 12 age-matched control children. The rs-MEG exams were performed in children with mTBI 6 months after injury when they reported no clinically significant post-injury psychiatric changes and few if any somatic sensorimotor symptoms but did report cognitive symptoms. MEG source magnitude images were obtained for different frequency bands in alpha (8-12 Hz), beta (15-30 Hz), gamma (30-90 Hz), and low-frequency (1-7 Hz) bands. In contrast to the control participants, rs-MEG source imaging in the children with mTBI showed: 1) hyperactivity from the bilateral insular cortices in alpha, beta, and low-frequency bands, from the left amygdala in alpha band, and from the left precuneus in beta band; 2) hypoactivity from the bilateral dorsolateral prefrontal cortices (dlPFC) in alpha and beta bands, from the ventromedial prefrontal cortex (vmPFC) in beta band, from the ventrolateral prefrontal cortex (vlPFC) in gamma band, from the anterior cingulate cortex (ACC) in alpha band, and from the right precuneus in alpha band. The present study showed that MEG source imaging technique revealed abnormalities in the resting-state electromagnetic signals from the children with mTBI.

Two-year prospective study of major depressive disorder in HIV-infected men.

OBJECTIVE: The risks and factors contributing to major depressive episodes in HIV infection remain unclear. This 2-year prospective study compared cumulative rates and predictors of a major depressive episode in HIV-infected (HIV+) men (N=297) and uninfected (HIV-) risk-group controls (N=90). METHODS: By design participants at entry were without current major depression, substance dependence or major anxiety disorder. Standardized neuromedical, neuropsychological, neuroimaging, life events, and psychiatric assessments (Structured Clinical Interview for DSM III-R) were conducted semi-annually for those with AIDS, and annually for all others. RESULTS: Lifetime prevalence of major depression or other psychiatric disorder did not differ at baseline between HIV+ men and controls. On a two-year follow-up those with symptomatic HIV disease were significantly more likely to experience a major depressive episode than were asymptomatic HIV+ individuals and HIV-controls (p<0.05). Episodes were as likely to be first onset as recurrent depression. After baseline disease stage and medical variables associated with HIV infection were controlled, a lifetime history of major depression, or of lifetime psychiatric comorbidity (two or more psychiatric disorders), predicted subsequent major depressive episode (p<0.05). Neither HIV disease progression during follow-up, nor the baseline presence of neurocognitive impairment, clinical brain imaging abnormality, or marked life adversity predicted a later major depressive episode. LIMITATIONS: Research cohort of men examined before era of widespread use of advanced anti-HIV therapies. CONCLUSIONS: Symptomatic HIV disease, but not HIV infection itself, increases intermediate-term risk of major depression. Prior psychiatric history most strongly predicted future vulnerability.

Cortical thickness in pediatric mild traumatic brain injury including sports-related concussion.

This investigation explored whether differences in cortical thickness could be detected in children who sustained a mild traumatic brain injury (mTBI) compared to those with orthopedic injury (OI) and whether cortical thickness related parental reporting of symptoms. To achieve this objective, FreeSurfer®-based cortical thickness measures were obtained in 330 children, 8 to 15 years of age, with either a history of mTBI or OI. Imaging was performed in all participants with the same 3 Tesla MRI scanner at six-months post-injury, where a parent-rated Post-Concussion Symptom Inventory (PCSI) was also obtained. Robust age-mediated reductions in cortical thickness were observed, but no consistent group-based differences between the mTBI and OI groups were observed. Also, the relation between mechanism of injury (i.e., sports-related, recreational, fall, motor vehicle accident or other) and cortical thickness was examined. Injuries associated with any type of abuse were excluded and children with OI could not have experienced a MVA. Mechanism of injury did not differentially relate to cortical thickness, although in the fall group, parental rating using the PCSI showed increased symptom reporting to be associated with reduced cortical thickness in the left interior frontal, temporal pole and lateral temporal lobe as well as in the right temporal pole. Results from these preliminary findings are discussed in terms of injury variables and developmental factors associated with mTBI in childhood.

Effects of HIV Infection, methamphetamine dependence and age on cortical thickness, area and volume.

OBJECTIVE: This study examined the effects of HIV infection, methamphetamine dependence and their interaction on cortical thickness, area and volume, as well as the potential interactive effects on cortical morphometry of HIV and methamphetamine with age. METHOD: T1-weighted structural images were obtained on a 3.0T General Electric MR750 scanner. Freesurfer v5.3.0 was used to derive cortical thickness, area and volume measures in thirty-four regions based on Desikan-Killiany atlas labels. RESULTS: Following correction for multiple statistical tests, HIV diagnosis was not significantly related to cortical thickness or area in any ROI, although smaller global cortical area and volume were seen in those with lower nadir CD4 count. HIV diagnosis, nevertheless, was associated with smaller mean cortical volumes in rostral middle frontal gyrus and in the inferior and superior parietal lobes. Methamphetamine dependence was significantly associated with thinner cortex especially in posterior cingulate gyrus, but was not associated with cortical area or volume following correction for multiple statistical tests. We found little evidence that methamphetamine dependence moderated differences in cortical area, volume or thickness for any ROI in the HIV seropositive group. Interactions with age revealed that HIV diagnosis attenuated the degree of age-related cortical thinning seen in non-infected individuals; intercepts indicated that young HIV seropositive individuals had thinner cortex than non-infected peers. CONCLUSIONS: Methamphetamine dependence does not appear to potentiate a reduction of cortical area, volume or thickness in HIV seropositive individuals. The finding of thinner cortex in young HIV seropositive individuals and the association between CD4 nadir and global cortical area and volume argue for prioritizing early antiretroviral treatment.

Abnormal diffusivity of normal appearing brain tissue in multiple sclerosis: a diffusion-weighted MR imaging study.

OBJECTIVE: To assess whether water diffusivity in normal appearing brain tissue including white and gray matter of multiple sclerosis (MS) patients shown by diffusion-weighted imaging (DWI) differs from normal individuals. MATERIAL AND METHOD: Conventional MRI and DWI were performed in 37 multiple sclerosis patients and 31 control subjects, matched for age and sex. Quantitative diffusivity values were obtained from variable locations of normal appearing white and gray matter from both hemispheres by using a standardized region of interest template. +/- 2. 9 x 10(-5) mm2/s and 85.90 x 10(-5) +/- 2.45 x 10(-5) mm2/s) than normal control subjects (NAWM: 73.46 x 10(-5) +/- 1.77 x 10(-5) mm2/s and NAGM: 82.90 x 10(-5) +/- 0.91 x 10(-5) mm2/s) with p-value < 0.0001. CONCLUSION: Water diffusivity was higher in all NAWM regions, deep gray matter regions, and some cortical gray matter region of MS patients than normal controls. DWI can quantify the presence and extent of MRI-undetectable pathology in the normal appearing brain tissue that were the disease burden.

Differential diagnostic approach to MR imaging of white matter diseases.

OBJECTIVES: The purpose of this article is to explore the magnetic resonance (MR) imaging features and the advanced MR techniques for differential diagnosis of white matter diseases of the brain. RESULTS: Magnetic resonance imaging is exquisitely sensitive for detecting brain abnormalities. Particularly in the evaluation of white matter diseases, MR far outperforms any other imaging technique. Lesions that may be quite subtle or even invisible on computed tomography are often clearly seen on the MR scan. The MR signal characteristics of white matter lesions are similar and relatively nonspecific, but other distinguishing features are often present to assist in diagnosis, such as the pattern of the abnormality, location, signal intensities, and enhancement features. Advanced MR techniques, such as diffusion-weighted imaging, MR spectroscopy, and perfusion imaging, provide additional specificity to the diagnosis of demyelinating diseases. CONCLUSIONS: Conventional MR images and advanced MR techniques are very helpful in distinguishing various types of white matter disease, for assessing disease burden, and for separating acute and chronic lesions.

ADC measurements in various patterns of multiple sclerosis lesions.

OBJECTIVE: To determine the difference of mean apparent diffusion coefficients (ADC) among different patterns of focal multiple sclerosis (MS) lesions, to compare mean lesion ADC between 2 clinical subgroups and to correlate mean lesion ADC with disability. MATERIAL AND METHOD: Thirty seven patients (26 with relapsing-remitting multiple sclerosis (MS) and 11 with secondary-progressive MS) underwent both conventional and diffusion-weighted MR imaging of the brain. After creating ADC maps, region identification was done by using b = 0 images and T2-weighted images. ADC values were measured for MS lesions and (NAWM). RESULTS: A total of 288 lesions were identified on the images. The mean ADC for the lesions was significantly higher than that of NAWM Hypointense T1 lesions (n = 221) had a significantly higher mean ADC than isointense T1 lesions (n = 67) in both nonenhancing lesions (n = 250) and enhancing lesions (n = 38). The enhanced rim of ring-enhancing lesions (n = 18) had lower ADC than the central nonenhanced portions. Confluent lesions (n = 62) had a substantially higher mean ADC than discrete lesion (n = 226). Mean lesion ADC of secondary progressive MS was significantly higher than relapsing remitting MS. No correlation between mean lesion ADC and (EDSS) score was found CONCLUSION: Quantitative diffusion-weighted imaging is useful to elucidate the heterogeneous pathological substrate of MS in different patterns of MS lesions, to differentiate 2 major clinical subgroups.

Structural Neuroimaging Findings in Mild Traumatic Brain Injury.

Common neuroimaging findings in mild traumatic brain injury (mTBI), including sport-related concussion (SRC), are reviewed based on computed tomography and magnetic resonance imaging (MRI). Common abnormalities radiologically identified on the day of injury, typically a computed tomographic scan, are in the form of contusions, small subarachnoid or intraparenchymal hemorrhages as well as subdural and epidural collections, edema, and skull fractures. Common follow-up neuroimaging findings with MRI include white matter hyperintensities, hypointense signal abnormalities that reflect prior hemorrhage, focal encephalomalacia, presence of atrophy and/or dilated Virchow-Robins perivascular space. The MRI findings from a large pediatric mTBI study show low frequency of positive MRI findings at 6 months postinjury. The review concludes with an examination of some of the advanced MRI-based image analysis methods that can be performed in the patient who has sustained an mTBI.

MR features of cerebral aspergillosis in an immunocompetent patient: correlation with histology and elemental analysis.

We report an unusual case of cerebral aspergillosis in a young immunocompetent patient who also had dissemination to other end organs. The patient presented with a large mass in the left cerebral hemisphere. Elemental analysis of biopsy specimens revealed elevated levels of iron, magnesium, zinc, calcium, chromium, and nickel that correlated with a peripheral rim of hypointensity on T2-weighted images.