IntroductionAttention-deficit hyperactive disorder (ADHD) is the most common neurodevelopmental disorder in children. Diagnosis is currently based on behavioral criteria, but magnetic resonance imaging (MRI) of the brain is increasingly used in ADHD research. To date however, MRI studies have provided mixed results in ADHD patients, particularly with respect to the laterality of findings.MethodsWe studied 849 children and adolescents (ages 6–21 y.o.) diagnosed with ADHD (n = 341) and age-matched typically developing (TD) controls with structural brain MRI. We calculated volumetric measures from 34 cortical and 14 non-cortical brain regions per hemisphere, and detailed shape morphometry of subcortical nuclei. Diffusion tensor imaging (DTI) data were collected for a subset of 104 subjects; from these, we calculated mean diffusivity and fractional anisotropy of white matter tracts. Group comparisons were made for within-hemisphere (right/left) and between hemisphere asymmetry indices (AI) for each measure.ResultsDTI mean diffusivity AI group differences were significant in cingulum, inferior and superior longitudinal fasciculus, and cortico-spinal tracts (p < 0.001) with the effect of stimulant treatment tending to reduce these patterns of asymmetry differences. Gray matter volumes were more asymmetric in medication free ADHD individuals compared to TD in twelve cortical regions and two non-cortical volumes studied (p < 0.05). Morphometric analyses revealed that caudate, hippocampus, thalamus, and amygdala were more asymmetric (p < 0.0001) in ADHD individuals compared to TD, and that asymmetry differences were more significant than lateralized comparisons.ConclusionsBrain asymmetry measures allow each individual to serve as their own control, diminishing variability between individuals and when pooling data across sites. Asymmetry group differences were more significant than lateralized comparisons between ADHD and TD subjects across morphometric, volumetric, and DTI comparisons.

Background:Like much of Sub-Saharan Africa, Uganda is facing significant maternal and fetal health challenges. Despite the fact that the majority of the Uganda population is rural and the major obstetrical care provider is the midwife, there is a lack of data in the literature regarding rural health facilities’ and midwives’ knowledge of ultrasound technology and perspectives on important maternal health issues such as deficiencies in prenatal services.Methodology:A survey of the current antenatal diagnostic and management capabilities of midwives at 12 rural Ugandan health facilities was performed as part of an international program initiated to provide ultrasound machines and formal training in their use to midwives at antenatal care clinics.Results:The survey revealed that the majority of pregnant women attend less than the recommended minimum of four antenatal care visits. There were significant knowledge deficits in many prenatal conditions that require ultrasound for early diagnosis, such as placenta previa and macrosomia. The cost of providing ultrasound machines and formal training to 12 midwives was $6,888 per powered rural health facility and $8,288 for non-powered rural health facilities in which solar power was required to maintain ultrasound.Conclusions and Global Health Implications:In order to more successfully meet Millennium Development Goal 4 (reduce child mortality), 5 (improve maternal health) and 6 (combat HIV) through decreasing maternal to child transmission of HIV, the primary healthcare provider, which is the midwife in Uganda, must be competent at the diagnosis and management of a wide spectrum of obstetrical challenges. A trained ultrasound-based approach to obstetrical care is a cost effective method to take on these goals.

Neuroimaging plays a critical role in the setting in traumatic brain injury (TBI). Diffusion tensor imaging (DTI) is an advanced magnetic resonance imaging technique that is capable of providing rich information on the brain’s neuroanatomic connectome. The purpose of this article is to systematically review the role of DTI and advanced diffusion techniques in the setting of TBI, including diffusion kurtosis imaging (DKI), neurite orientation dispersion and density imaging, diffusion spectrum imaging, and q-ball imaging. We discuss clinical applications of DTI and review the DTI literature as it pertains to TBI. Despite the continued advancements in DTI and related diffusion techniques over the past 20 years, DTI techniques are sensitive for TBI at the group level only and there is insufficient evidence that DTI plays a role at the individual level. We conclude by discussing future directions in DTI research in TBI including the role of machine learning in the pattern classification of TBI.

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The purpose of this article is to review conventional and advanced neuroimaging techniques performed in the setting of traumatic brain injury (TBI). The primary goal for the treatment of patients with suspected TBI is to prevent secondary injury. In the setting of a moderate to severe TBI, the most appropriate initial neuroimaging examination is a noncontrast head computed tomography (CT), which can reveal life-threatening injuries and direct emergent neurosurgical intervention. We will focus much of the article on advanced neuroimaging techniques including perfusion imaging and diffusion tensor imaging and discuss their potentials and challenges. We believe that advanced neuroimaging techniques may improve the accuracy of diagnosis of TBI and improve management of TBI.