Associations Between Early-Life Adversity, Ambient Air Pollution, and Telomere Length in Children.

OBJECTIVE: Examine the independent associations and interaction between early-life adversity and residential ambient air pollution exposure on relative buccal telomere length (rBTL). METHODS: Experiences of abuse, neglect, household challenges, and related life events were identified in a cross-sectional sample of children aged 1 to 11 years ( n = 197) using the 17-item Pediatric ACEs and Related Life Event Screener (PEARLS) tool. The PEARLS tool was analyzed both as a total score and across established domains (Maltreatment, Household Challenges, and Social Context). Ground-level fine particulate matter (PM 2.5 ) concentrations were matched to residential locations for the 1 and 12 months before biospecimen collection. We used multivariable linear regression models to examine for independent associations between continuous PM 2.5 exposure and PEARLS score/domains with rBTL. In addition, effect modification by PEARLS scores and domains on associations between PM 2.5 exposure and rBTL was examined. RESULTS: Study participants were 47% girls, with mean (standard deviation) age of 5.9 (3.4) years, median reported PEARLS score of 2 (interquartile range [IQR], 4), median 12-month prior PM 2.5 concentrations of 11.8 µg/m 3 (IQR, 2.7 µg/m 3 ), median 1-month prior PM 2.5 concentrations of 10.9 µg/m 3 (IQR, 5.8 µg/m 3 ), and rBTL of 0.1 (IQR, 0.03). Mean 12-month prior PM 2.5 exposure was inversely associated with rBTL ( ß = -0.02, 95% confidence interval = -0.04 to -0.01). Although reported PEARLS scores and domains were not independently associated with rBTL, we observed a greater decrement in rBTL with increment of average annual PM 2.5 as reported Social Context domain items increased ( p -interaction < .05). CONCLUSIONS: Our results suggest that adverse Social Context factors may accelerate the association between chronic PM 2.5 exposure on telomere shortening during childhood.

Adverse Childhood Experiences and Related Events are Associated with Asthma Symptoms in Children.

OBJECTIVE: To examine the association between adverse childhood experiences (ACEs) and related events and asthma symptom burden in children. METHODS: This is a cross-sectional study of baseline data from 147 participants with asthma from a cohort of children enrolled in the Pediatric ACEs Screening and Resiliency Study. Participants completed the PEdiatric ACEs and Related Life Events Screener (PEARLS) tool, a 17-item questionnaire, capturing 3 domains of childhood adversity-child maltreatment, household challenges, and social context. Asthma symptom burden was assessed using the International Study of Asthma and Allergies in Childhood core questionnaire, which asks participants to identify the presence and frequency of severe wheezing that limits speech, wheezing with exercise, nocturnal wheezing, and nocturnal cough in the last 12 months. Using multivariable logistical regression models, we examined the relationship between reported PEARLS and asthma symptoms. RESULTS: Of children with asthma, 86% reported at least 1 adversity, with 48% reporting 4 or more. The odds of severe wheeze limiting speech increased by 19% with each additional reported adversity captured by the PEARLS tool (95% confidence intervals (CI) 1.01-1.41). Increasing PEARLS scores were also associated with 16% increased odds of reporting wheeze with exercise (95% CI 1.03-1.31). Wheezing with exercise was associated with the household challenges domain (odds ratio (OR) 1.34; 95% CI 1.05-1.72), while severe wheeze limiting speech was associated with the social context domain (OR 1.75; 95%CI 1.02-3.02). CONCLUSIONS: Childhood adversities are associated with increased asthma symptom burden, suggesting the tool may be helpful in identifying children at risk for poorly controlled asthma.

Pediatric ACEs and related life event screener (PEARLS) latent domains and child health in a safety-net primary care practice.

BACKGROUND: Research examining the connections between individual adverse childhood experiences (ACEs) and how groupings of interrelated adversities are linked with subsequent health is scarce, limiting our understanding of risk during a period of rapid expansion of ACE screening in clinical practice. The study objective was to conduct a psychometric analysis to derive latent domains of ACEs and related life events and assess the association between each domain and health outcome. METHODS: Participants (3 months-11 years) were recruited from the University of California San Francisco Benioff's Children Hospital Oakland Primary Care Clinic. Children were screened with the Pediatric ACEs and Related Life Events Screener (PEARLS) (n = 340), which assessed 17 total ACEs and related life events, including forms of abuse, household challenges, and social risks. Domains were constructed using confirmatory factor analysis and associations between the three identified domains and 14 health outcomes were assessed using multivariable linear and logistic regression models. RESULTS: Three PEARLS domains were identified: Maltreatment (ω = 0.73, ɑ=0.87), Household Challenges (ω = 0.70, ɑ=0.82), and Social Context (ω = 0.55, ɑ=0.70). Measurement invariance was supported across both gender and screening format. All domains were associated with poorer general and behavioral health and stomachaches. Maltreatment and Social Context were additionally associated with eczema while only Social Context was associated with increased odds of reporting headaches and somatic symptoms. CONCLUSION: In an underserved, urban west-coast pediatric population, the PEARLS found three adversity domains of Maltreatment, Household Challenges, and Social Context that all had an independent statistically significant association with poorer child health. The results provide a timely and more nuanced representation of risk that can inform clinical practice and policy using more targeted resources and interventions.

Biological Burden of Adverse Childhood Experiences in Children.

OBJECTIVE: This study aimed to examine relationships between adverse childhood experiences (ACEs) and related life events and allostatic load (AL)-"wear and tear" from chronic stress-in a pediatric population. METHODS: Children were screened with the PEdiatric ACEs and Related Life Event Screener (PEARLS) tool, a 17-item questionnaire capturing experiences of abuse, neglect, household challenges, and related life events. Biological data were available for 207 participants, and AL was operationalized using clinical or empirical cutoff points across 4 physiological systems (i.e., cardiac, metabolic, inflammatory, neurologic). Covariate-adjusted multivariable regression models were used to examine associations between AL with adversity and health. RESULTS: Children (mean age = 6.5 years, range = 1-11 years) had an average AL score of 1.9 (standard deviation = 1.7), and a U-shaped relationship was observed with child's age. Continuous PEARLS and original ACE scores were not associated with AL. However, children with a reported PEARLS score of 1 to 2 or original ACEs score of 1 to 3 had 1.5 (incidence rate ratio [IRR] = 1.50, 95% confidence interval [CI] = 1.09-2.08) and 1.4 (IRR = 1.41, 95% CI = 1.08-1.84) times greater AL, respectively, compared with participants with none reported. In secondary analyses, caregiver mental illness was associated with higher child AL (adjusted IRR = 1.27, 95% CI = 1.01-1.58). AL was also associated with poorer perceived child general health (adjusted ß = -0.87, 95% CI = -1.58 to -0.15) and greater odds of child obesity (adjusted odds ratio = 1.51, 95% CI = 1.23-1.89). CONCLUSIONS: Measuring AL in a pediatric population requires careful consideration of age. Higher AL was associated with a greater number of reported adversities and worse child health.

Screening for adverse childhood experiences in pediatrics: A randomized trial of aggregate-level versus item-level response screening formats.

BACKGROUND: While there is growing support for screening for Adverse Childhood Experiences (ACEs), rigorous evidence on the efficacy and preference of screening methods is needed. OBJECTIVE: To examine caregiver: (1) rates of disclosure of their child's exposure to ACEs using item-level response (each item can be endorsed) versus aggregate-level response (only total score reported) screening format, (2) associations between family demographic factors and disclosure by screening format, and (3) emotional reaction and experience of screening formats in a diverse, low-income pediatric population. METHODS: Caregiver participants (n = 367) were randomized to complete the Pediatric ACEs and Related Life Events Screener (PEARLS) tool, in an aggregate-level response vs item-level response format from 2016-2019. Select caregivers (n = 182) participated in debriefing interviews. T-test and chi-square analyses in 2019 compared PEARLS disclosure rates and reactions between the screening modalities. Regression models explored interactions with child characteristics. Thematic analysis of interview notes captured caregiver screening experience. RESULTS: PEARLS disclosure rates were significantly higher in the aggregate-level response compared to the item-level response screening arm (p <0.05). This difference was accentuated for children identified as black and/or male (p <0.05). Caregiver reactions to PEARLS screening were rarely negative in either screening format. Qualitative data demonstrated strong caregiver preference for the item-level response format; additional themes include provider relationship, fear with disclosure, and screening outcome expectations. CONCLUSION: While caregivers reported a preference for the item-level response format, the aggregate-level response screening format elicited higher disclosures rates particularly for children who are black or ma. TRIAL REGISTRATION: Clinical trial registry: NCT04182906.

A Caregiver-Child Intervention for Mitigating Toxic Stress ("The Resiliency Clinic"): A Pilot Study.

INTRODUCTION: Primary care-based interventions that promote nurturing caregiving relationships and early relational health may help mitigate toxic stress and promote resilience in children. This pilot study aims to: (1) describe a novel group-based, psychoeducational primary care intervention for children experiencing adverse childhood experiences (ACEs) ("The Resiliency Clinic"), (2) assess program feasibility and acceptability, and (3) explore effects on child/caregiver behavioral health. METHODS: Intervention design centered on promoting supportive caregiving, caregiver/child self-regulation and co-regulation and teaching evidence-based stress management tools. Program feasibility and acceptability were assessed through attendance data and caregiver focus groups. Behavioral health measures were obtained at baseline and 8-month follow-up. RESULTS: Of 101 eligible families, 38 (37.6%) enrolled and attended a median of 3.00 (mean = 2.95, sd = 1.75) out of 6 sessions. Caregivers reported high satisfaction and benefits including stress management tools and connection with staff and other parents. There were modest, statistically non-significant improvements in caregiver stress (d = 0.23) and child executive functioning (d = 0.27). DISCUSSION: In conclusion, a group intervention teaching supportive caregiving and stress mitigation is feasible and acceptable for many families in an urban federally qualified health center (FQHC) with a signal for modest improvements in behavioral health. Future program iterations will seek to address participation barriers and expand the intervention's capacity to promote early relational health.

Pediatrics adverse childhood experiences and related life events screener (PEARLS) and health in a safety-net practice.

BACKGROUND: Adverse Childhood Experiences (ACEs) are associated with behavioral, mental, and clinical outcomes in children. Tools that are easy to incorporate into pediatric practice, effectively screen for adversities, and identify children at high risk for poor outcomes are lacking. OBJECTIVE: To examine the relationship between caregiver-reported child ACEs and related life events with health outcomes. PARTICIPANTS AND SETTING: Participants (0-11 years) were recruited from the University of California San Francisco Benioff's Children Hospital Oakland Primary Care Clinic. There were 367 participants randomized. METHODS: Participants were randomized 1:1:1 to item-level (item response), aggregate-level (total number of exposures), or no screening for ACEs (control arm) with the PEdiatric ACEs and Related Life Event Screener (PEARLS). We assessed 10 ACE categories capturing abuse, neglect, and household challenges, as well as 7 additional categories. Multivariable regression models were conducted. RESULTS: Participants reported a median of 2 (IQR 1-5) adversities with 76 % (n = 279) reporting at least one adversity; participants in the aggregate-level screening arm, on average, disclosed 1 additional adversity compared to item-level screening (p = 0.01). Higher PEARLS scores were associated with poorer perceived child general health (adjusted B = -0.94, 95 %CI: -1.26, -0.62) and Global Executive Functioning (adjusted B = 1.99, 95 %CI: 1.51, 2.46), and greater odds of stomachaches (aOR 1.14; 95 %CI: 1.04-1.25) and asthma (aOR 1.08; 95 %CI 1.00, 1.17). Associations did not differ by screening arm. CONCLUSION: In a high-risk pediatric population, ACEs and other childhood adversities remain an independent predictor of poor health. Increased efforts to screen and address early-life adversity are necessary.

Development and implementation of a pediatric adverse childhood experiences (ACEs) and other determinants of health questionnaire in the pediatric medical home: A pilot study.

Adverse Childhood Experiences (ACEs) are associated with poor health outcomes, underlining the significance of early identification and intervention. Currently, there is no validated tool to screen for ACEs exposure in childhood. To fill this gap, we designed and implemented a pediatric ACEs questionnaire in an urban pediatric Primary Care Clinic. Questionnaire items were selected and modified based on literature review of existing childhood adversity tools. Children twelve years and under were screened via caregiver report, using the developed instrument. Cognitive interviews were conducted with caregivers, health providers, and clinic staff to assess item interpretation, clarity, and English/Spanish language equivalency. Using a rapid cycle assessment, information gained from the interviews were used to iteratively change the instrument. Additional questions assessed acceptability of screening within primary care and preferences around administration. Twenty-eight (28) caregivers were administered the questionnaire. Cognitive interviews conducted among caregivers and among 16 health providers and clinic staff resulted in the changes in wording and addition of examples in the items to increase face validity. In the final instrument, no new items were added; however, two items were merged and one item was split into three separate items. While there was a high level of acceptability of the overall questionnaire, some caregivers reported discomfort with the sexual abuse, separation from caregiver, and community violence items. Preference for methods of administration were split between tablet and paper formats. The final Pediatric ACE and other Determinants of Health Questionnaire is a 17-item instrument with high face validity and acceptability for use within primary care settings. Further evaluation on the reliability and construct validity of the instrument is being conducted prior to wide implementation in pediatric practice.

Review of Tools for Measuring Exposure to Adversity in Children and Adolescents.

Exposure to childhood adversity can result in negative behavioral and physical health outcomes due to potential long-term embedding into regulatory biological processes. Screening for exposure to adversity is a critical first step in identifying children at risk for developing a toxic stress response. We searched PubMed, PsycArticles, and CINAHL for studies published between January 1, 2012, and December 31, 2016, as well as other sources, to identify potential tools for measuring cumulative adversity in children and adolescents. We identified 32 tools and examined them for adversity categories, target population, administration time, administration qualifications and method, and reliability and validity. We also created a list of recommended tools that would be feasible for use by pediatric practitioners in most types of practice. This review provides a starting point for mobilizing screening in pediatric settings, highlighting the challenges with existing tools, and potential issues in the development and evaluation of future tools.

Ameliorating the biological impacts of childhood adversity: A review of intervention programs.

Childhood adversity negatively impacts the biological development of children and has been linked to poor health outcomes across the life course. The purpose of this literature review is to explore and evaluate the effectiveness of interventions that have addressed an array of biological markers and physical health outcomes in children and adolescents affected by adversity. PubMed, CINAHL, PsychInfo, Sociological Abstracts databases and additional sources (Cochrane, WHO, NIH trial registries) were searched for English language studies published between January 2007 and September 2017. Articles with a childhood adversity exposure, biological health outcome, and evaluation of intervention using a randomized controlled trial study design were selected. The resulting 40 intervention studies addressed cortisol outcomes (n = 20) and a range of neurological, epigenetic, immune, and other outcomes (n = 22). Across institutional, foster care, and community settings, intervention programs demonstrated success overall for improving or normalizing morning and diurnal cortisol levels, and ameliorating the impacts of adversity on brain development, epigenetic regulation, and additional outcomes in children. Factors such as earlier timing of intervention, high quality and nurturant parenting traits, and greater intervention engagement played a role in intervention success. This study underlines progress and promise in addressing the health impacts of adversity in children. Ongoing research efforts should collect baseline data, improve retention, replicate studies in additional samples and settings, and evaluate additional variables, resilience factors, mediators, and long-term implications of results. Clinicians should integrate lessons from the intervention sciences for preventing and treating the health effects of adversity in children and adolescents.

Systematic review of pediatric health outcomes associated with childhood adversity.

BACKGROUND: Early detection of and intervention in childhood adversity has powerful potential to improve the health and well-being of children. A systematic review was conducted to better understand the pediatric health outcomes associated with childhood adversity. METHODS: PubMed, PsycArticles, and CINAHL were searched for relevant articles. Longitudinal studies examining various adverse childhood experiences and biological health outcomes occurring prior to age 20 were selected. Mental and behavioral health outcomes were excluded, as were physical health outcomes that were a direct result of adversity (i.e. abusive head trauma). Data were extracted and risk of bias was assessed by 2 independent reviewers. RESULTS: After identifying 15940 records, 35 studies were included in this review. Selected studies indicated that exposure to childhood adversity was associated with delays in cognitive development, asthma, infection, somatic complaints, and sleep disruption. Studies on household dysfunction reported an effect on weight during early childhood, and studies on maltreatment reported an effect on weight during adolescence. Maternal mental health issues were associated with elevated cortisol levels, and maltreatment was associated with blunted cortisol levels in childhood. Furthermore, exposure to childhood adversity was associated with alterations of immune and inflammatory response and stress-related accelerated telomere erosion. CONCLUSION: Childhood adversity affects brain development and multiple body systems, and the physiologic manifestations can be detectable in childhood. A history of childhood adversity should be considered in the differential diagnosis of developmental delay, asthma, recurrent infections requiring hospitalization, somatic complaints, and sleep disruption. The variability in children's response to adversity suggests complex underlying mechanisms and poses a challenge in the development of uniform diagnostic guidelines. More large longitudinal studies are needed to better understand how adversity, its timing and severity, and the presence of individual genetic, epigenetic, and protective factors affects children's health and development.

Long-term evolution of multiple sclerosis disability in the treatment era.

OBJECTIVE: To characterize the accrual of long-term disability in a cohort of actively treated multiple sclerosis (MS) patients and to assess whether clinical and magnetic resonance imaging (MRI) data used in clinical trials have long-term prognostic value. METHODS: This is a prospective study of 517 actively managed MS patients enrolled at a single center. RESULTS: More than 91% of patients were retained, with data ascertained up to 10 years after the baseline visit. At this last assessment, neurologic disability as measured by the Expanded Disability Status Scale (EDSS) was stable or improved compared to baseline in 41% of patients. Subjects with no evidence of disease activity (NEDA) by clinical and MRI criteria during the first 2 years had long-term outcomes that were no different from those of the cohort as a whole. 25-OH vitamin D serum levels were inversely associated with short-term MS disease activity; however, these levels had no association with long-term disability. At a median time of 16.8 years after disease onset, 10.7% (95% confidence interval [CI] = 7.2-14%) of patients reached an EDSS ≥ 6, and 18.1% (95% CI = 13.5-22.5%) evolved from relapsing MS to secondary progressive MS (SPMS). INTERPRETATION: Rates of worsening and evolution to SPMS were substantially lower when compared to earlier natural history studies. Notably, the NEDA 2-year endpoint was not a predictor of long-term stability. Finally, the data call into question the utility of annual MRI assessments as a treat-to-target approach for MS care. Ann Neurol 2016;80:499-510.

Association Between Thoracic Spinal Cord Gray Matter Atrophy and Disability in Multiple Sclerosis.

IMPORTANCE: In multiple sclerosis (MS), upper cervical cord gray matter (GM) atrophy correlates more strongly with disability than does brain or cord white matter (WM) atrophy. The corresponding relationships in the thoracic cord are unknown owing to technical difficulties in assessing GM and WM compartments by conventional magnetic resonance imaging techniques. OBJECTIVES: To investigate the associations between MS disability and disease type with lower thoracic cord GM and WM areas using phase-sensitive inversion recovery magnetic resonance imaging at 3 T, as well as to compare these relationships with those obtained at upper cervical levels. DESIGN, SETTING, AND PARTICIPANTS: Between July 2013 and March 2014, a total of 142 patients with MS (aged 25-75 years; 86 women) and 20 healthy control individuals were included in this cross-sectional observational study conducted at an academic university hospital. MAIN OUTCOMES AND MEASURES: Total cord areas (TCAs), GM areas, and WM areas at the disc levels C2/C3, C3/C4, T8/9, and T9/10. Area differences between groups were assessed, with age and sex as covariates. RESULTS: Patients with relapsing MS (RMS) had smaller thoracic cord GM areas than did age- and sex-matched control individuals (mean differences [coefficient of variation (COV)]: 0.98 mm2 [9.2%]; P = .003 at T8/T9 and 0.93 mm2 [8.0%]; P = .01 at T9/T10); however, there were no significant differences in either the WM area or TCA. Patients with progressive MS showed smaller GM areas (mean differences [COV]: 1.02 mm2 [10.6%]; P < .001 at T8/T9 and 1.37 mm2 [13.2%]; P < .001 at T9/T10) and TCAs (mean differences [COV]: 3.66 mm2 [9.0%]; P < .001 at T8/T9 and 3.04 mm2 [7.2%]; P = .004 at T9/T10) compared with patients with RMS. All measurements (GM, WM, and TCA) were inversely correlated with Expanded Disability Status Scale score. Thoracic cord GM areas were correlated with lower limb function. In multivariable models (which also included cord WM areas and T2 lesion number, brain WM volumes, brain T1 and fluid-attenuated inversion recovery lesion loads, age, sex, and disease duration), cervical cord GM areas had the strongest correlation with Expanded Disability Status Scale score followed by thoracic cord GM area and brain GM volume. CONCLUSIONS AND RELEVANCE: Thoracic cord GM atrophy can be detected in vivo in the absence of WM atrophy in RMS. This atrophy is more pronounced in progressive MS than RMS and correlates with disability and lower limb function. Our results indicate that remarkable cord GM atrophy is present at multiple cervical and lower thoracic levels and, therefore, may reflect widespread cord GM degeneration.

Spinal cord gray matter atrophy correlates with multiple sclerosis disability.

OBJECTIVE: In multiple sclerosis (MS), cerebral gray matter (GM) atrophy correlates more strongly than white matter (WM) atrophy with disability. The corresponding relationships in the spinal cord (SC) are unknown due to technical limitations in assessing SC GM atrophy. Using phase-sensitive inversion recovery (PSIR) magnetic resonance imaging, we determined the association of the SC GM and SC WM areas with MS disability and disease type. METHODS: A total of 113 MS patients and 20 healthy controls were examined at 3T with a PSIR sequence acquired at the C2/C3 disk level. Two independent, clinically masked readers measured the cord WM and GM areas. Correlations between cord areas and Expanded Disability Status Score (EDSS) were determined. Differences in areas between groups were assessed with age and sex as covariates. RESULTS: Relapsing MS (RMS) patients showed smaller SC GM areas than age- and sex-matched controls (p = 0.008) without significant differences in SC WM areas. Progressive MS patients showed smaller SC GM and SC WM areas compared to RMS patients (all p ≤ 0.004). SC GM, SC WM, and whole cord areas inversely correlated with EDSS (rho: -0.60, -0.32, -0.42, respectively; all p ≤ 0.001). The SC GM area was the strongest correlate of disability in multivariate models including brain GM and WM volumes, fluid-attenuated inversion recovery lesion load, T1 lesion load, SC WM area, number of SC T2 lesions, age, sex, and disease duration. Brain and spinal GM independently contributed to EDSS. INTERPRETATION: SC GM atrophy is detectable in vivo in the absence of WM atrophy in RMS. It is more pronounced in progressive MS than RMS and contributes more to patient disability than SC WM or brain GM atrophy.

Quantifying accuracy and precision of diffusion MR tractography of the corticospinal tract in brain tumors.

OBJECT: The aim of this paper was to validate the diffusion tensor imaging (DTI) model for delineation of the corticospinal tract using cortical and subcortical white matter electrical stimulation for the location of functional motor pathways. METHODS: The authors compare probabilistic versus deterministic DTI fiber tracking by reconstructing the pyramidal fiber tracts on preoperatively acquired DTI in patients with brain tumors. They determined the accuracy and precision of these 2 methods using subcortical stimulation points and the sensitivity using cortical stimulation points. The authors further explored the reliability of these methods by estimation of the potential that the found connections were due to a random chance using a novel neighborhood permutation method. RESULTS: The probabilistic tracking method delineated tracts that were significantly closer to the stimulation points and was more sensitive than deterministic DTI fiber tracking to define the tracts directed to the motor sites. However, both techniques demonstrated poor sensitivity to finding lateral motor regions. CONCLUSIONS: This study highlights the importance of the validation and quantification of preoperative fiber tracking with the aid of electrophysiological data during the surgery. The poor sensitivity of DTI to delineate lateral motor pathways reported herein suggests that DTI fiber tracking must be used with caution and only as adjunctive data to established methods for motor mapping.

Validation of FDG uptake in the arterial wall as an imaging biomarker of atherosclerotic plaques with 18F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG-PET/CT).

BACKGROUND AND PURPOSE: From the literature, the prevalence of fluorodeoxyglucose (FDG) uptake in large artery atherosclerotic plaques shows great heterogeneity. We retrospectively reviewed 100 consecutive patients who underwent FDG-positron emission tomography-computed tomography (PET/CT) imaging of their whole body, to evaluate FDG uptake in the arterial wall. MATERIALS AND METHODS: We retrospectively evaluated 100 whole-body PET-CT scans. The PET images coregistered with CT were reviewed for abnormal 18F-FDG uptake. The mean standard uptake value (SUV) was measured in regions of interest (ROIs). The prevalence of PET+ plaques was determined based on the qualitative PET review, used as the gold standard in a receiver-operating characteristic (ROC) curve analysis to determine an optimal threshold for the quantitative PET analysis. RESULTS: The qualitative, visual assessment demonstrated FDG uptake in the arterial walls of 26 patients. A total of 85 slices exhibited FDG uptake within the arterial wall of 37 artery locations. 11, 17, and 2 patients exhibited FDG uptake within the wall of carotid arteries, of the aorta, and of the iliac arteries, respectively. Only 4 of the 26 patients had positive FDG uptake in more than one artery location. In terms of quantitative analysis, a threshold of 2.8 SUV was associated with a negative predictive value of 99.4% and a positive predictive value of 100% to predict qualitative PET+ plaques. A threshold of 1.8 SUV was associated with a negative predictive value of 100% and a positive predictive value of 99.4%. Area under the ROC curve was .839. CONCLUSION: The prevalence of PET uptake in arterial walls in a consecutive population of asymptomatic patients is low and usually confined to one type of artery, and its clinical relevance in terms of vulnerability to ischemic events remains to be determined.

Quantifying diffusion MRI tractography of the corticospinal tract in brain tumors with deterministic and probabilistic methods.

INTRODUCTION: Diffusion MRI tractography has been increasingly used to delineate white matter pathways in vivo for which the leading clinical application is presurgical mapping of eloquent regions. However, there is rare opportunity to quantify the accuracy or sensitivity of these approaches to delineate white matter fiber pathways in vivo due to the lack of a gold standard. Intraoperative electrical stimulation (IES) provides a gold standard for the location and existence of functional motor pathways that can be used to determine the accuracy and sensitivity of fiber tracking algorithms. In this study we used intraoperative stimulation from brain tumor patients as a gold standard to estimate the sensitivity and accuracy of diffusion tensor MRI (DTI) and q-ball models of diffusion with deterministic and probabilistic fiber tracking algorithms for delineation of motor pathways. METHODS: We used preoperative high angular resolution diffusion MRI (HARDI) data (55 directions, b = 2000 s/mm(2)) acquired in a clinically feasible time frame from 12 patients who underwent a craniotomy for resection of a cerebral glioma. The corticospinal fiber tracts were delineated with DTI and q-ball models using deterministic and probabilistic algorithms. We used cortical and white matter IES sites as a gold standard for the presence and location of functional motor pathways. Sensitivity was defined as the true positive rate of delineating fiber pathways based on cortical IES stimulation sites. For accuracy and precision of the course of the fiber tracts, we measured the distance between the subcortical stimulation sites and the tractography result. Positive predictive rate of the delineated tracts was assessed by comparison of subcortical IES motor function (upper extremity, lower extremity, face) with the connection of the tractography pathway in the motor cortex. RESULTS: We obtained 21 cortical and 8 subcortical IES sites from intraoperative mapping of motor pathways. Probabilistic q-ball had the best sensitivity (79%) as determined from cortical IES compared to deterministic q-ball (50%), probabilistic DTI (36%), and deterministic DTI (10%). The sensitivity using the q-ball algorithm (65%) was significantly higher than using DTI (23%) (p < 0.001) and the probabilistic algorithms (58%) were more sensitive than deterministic approaches (30%) (p = 0.003). Probabilistic q-ball fiber tracks had the smallest offset to the subcortical stimulation sites. The offsets between diffusion fiber tracks and subcortical IES sites were increased significantly for those cases where the diffusion fiber tracks were visibly thinner than expected. There was perfect concordance between the subcortical IES function (e.g. hand stimulation) and the cortical connection of the nearest diffusion fiber track (e.g. upper extremity cortex). DISCUSSION: This study highlights the tremendous utility of intraoperative stimulation sites to provide a gold standard from which to evaluate diffusion MRI fiber tracking methods and has provided an object standard for evaluation of different diffusion models and approaches to fiber tracking. The probabilistic q-ball fiber tractography was significantly better than DTI methods in terms of sensitivity and accuracy of the course through the white matter. The commonly used DTI fiber tracking approach was shown to have very poor sensitivity (as low as 10% for deterministic DTI fiber tracking) for delineation of the lateral aspects of the corticospinal tract in our study. Effects of the tumor/edema resulted in significantly larger offsets between the subcortical IES and the preoperative fiber tracks. The provided data show that probabilistic HARDI tractography is the most objective and reproducible analysis but given the small sample and number of stimulation points a generalization about our results should be given with caution. Indeed our results inform the capabilities of preoperative diffusion fiber tracking and indicate that such data should be used carefully when making pre-surgical and intra-operative management decisions.

Neural stem cell engraftment and myelination in the human brain.

Pelizaeus-Merzbacher disease (PMD) is a rare leukodystrophy caused by mutation of the proteolipid protein 1 gene. Defective oligodendrocytes in PMD fail to myelinate axons, causing global neurological dysfunction. Human central nervous system stem cells (HuCNS-SCs) can develop into oligodendrocytes and confer structurally normal myelin when transplanted into a hypomyelinating mouse model. A 1-year, open-label phase-1 study was undertaken to evaluate safety and to detect evidence of myelin formation after HuCNS-SC transplantation. Allogeneic HuCNS-SCs were surgically implanted into the frontal lobe white matter in four male subjects with an early-onset severe form of PMD. Immunosuppression was administered for 9 months. Serial neurological evaluations, developmental assessments, and cranial magnetic resonance imaging (MRI) and MR spectroscopy, including high-angular resolution diffusion tensor imaging (DTI), were performed at baseline and after transplantation. The neurosurgical procedure, immunosuppression regimen, and HuCNS-SC transplantation were well tolerated. Modest gains in neurological function were observed in three of the four subjects. No clinical or radiological adverse effects were directly attributed to the donor cells. Reduced T1 and T2 relaxation times were observed in the regions of transplantation 9 months after the procedure in the three subjects. Normalized DTI showed increasing fractional anisotropy and reduced radial diffusivity, consistent with myelination, in the region of transplantation compared to control white matter regions remote to the transplant sites. These phase 1 findings indicate a favorable safety profile for HuCNS-SCs in subjects with PMD. The MRI results suggest durable cell engraftment and donor-derived myelin in the transplanted host white matter.