Head motion systematically distorts clinical and research MRI data. Motion artifacts have biased findings from many structural and functional brain MRI studies. An effective way to remove motion artifacts is to exclude MRI data frames affected by head motion. However, such post-hoc frame censoring can lead to data loss rates of 50% or more in our pediatric patient cohorts. Hence, many scanner operators collect additional ‘buffer data’, an expensive practice that, by itself, does not guarantee sufficient high-quality MRI data for a given participant. Therefore, we developed an easy-to-setup, easy-to-use Framewise Integrated Real-time MRI Monitoring (FIRMM) software suite that provides scanner operators with head motion analytics in real-time, allowing them to scan each subject until the desired amount of low-movement data has been collected. Our analyses show that using FIRMM to identify the ideal scan time for each person can reduce total brain MRI scan times and associated costs by 50% or more.

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OBJECTIVE -Despite interest in the effects of type 1 diabetes on the developing brain, structural brain volumes in youth with this disease have not previously been examined. This study is the first to quantify regional brain volume differences in a large sample of youth with diabetes. RESEARCH DESIGN AND METHODS -Magnetic resonance images (MRIs)were acquired from youth with diabetes (n ϭ 108) and healthy sibling control subjects (n ϭ 51) aged 7-17 years. History of severe hypoglycemia was assessed by parent interview and included seizure, loss of consciousness, or requiring assistance to treat. A1C values since diagnosis were obtained from medical records; median A1C was weighted by duration of disease. Voxel-based morphometry was used to determine the relationships of prior hypo-and hyperglycemia to regional grey and white matter volumes across the whole brain.RESULTS -No significant differences were found between diabetic and healthy control groups in grey or white matter. However, within the diabetic group, a history of severe hypoglycemia was associated with smaller grey matter volume in the left superior temporal region. Greater exposure to hyperglycemia was associated with smaller grey matter volume in the right cuneus and precuneus, smaller white matter volume in a right posterior parietal region, and larger grey matter volume in a right prefrontal region.CONCLUSIONS -Qualitatively different relationships were found between hypo-and hyperglycemia and regional brain volumes in youth with type 1 diabetes. Future studies should investigate whether these differences relate to cognitive function and how these regions are affected by further exposure. Diabetes Care 30:2331-2337, 2007T ype 1 diabetes is known to have cumulative deleterious effects on the body, most notably on the retina, kidney, nerves, and blood vessels (1,2).The effects of diabetes on central nervous system structure and function are less well understood. A number of studies associate exposure to hypo-and hyperglycemia during childhood with deficits in specific cognitive domains (3,4). These findings suggest that during development, exposure to glycemic extremes may alter the structure or function of specific pathways or regions in the brain. Recent brain imaging studies in diabetic adults have reported differences in grey or white matter integrity associated with prior hypo-or hyperglycemia (5,6). However, the effects of diabetes on the developing brain have not been assessed in any largescale study to date (7). Assessing brain integrity earlier in the course of brain development and diabetes, followed by prospective monitoring, would be essential to determine when differences may emerge. Such knowledge could shed light on the neural basis of observed cognitive effects in children and adults with diabetes and determine whether there are developmental time periods during which the brain may be particularly vulnerable to the negative effects of hypoglycemia or hyperglycemia.The present study is the first to examine the structural integrity of t...

A major limitation to structural and functional MRI (fMRI) scans is their susceptibility to head motion artifacts. Even submillimeter movements can systematically distort functional connectivity, morphometric, and diffusion imaging results. In patient care, sedation is often used to minimize head motion, but it incurs increased costs and risks. In research settings, sedation is typically not an ethical option. Therefore, safe methods that reduce head motion are critical for improving MRI quality, especially in high movement individuals such as children and neuropsychiatric patients. We investigated the effects of (1) viewing movies and (2) receiving real-time visual feedback about head movement in 24 children (5-15 years old). Children completed fMRI scans during which they viewed a fixation cross (i.e., rest) or a cartoon movie clip, and during some of the scans they also received real-time visual feedback about head motion. Head motion was significantly reduced during movie watching compared to rest and when receiving feedback compared to receiving no feedback. However, these results depended on age, such that the effects were largely driven by the younger children. Children older than 10 years showed no significant benefit. We also found that viewing movies significantly altered the functional connectivity of fMRI data, suggesting that fMRI scans during movies cannot be equated to standard resting-state fMRI scans. The implications of these results are twofold: (1) given the reduction in head motion with behavioral interventions, these methods should be tried first for all clinical and structural MRIs in lieu of sedation; and (2) for fMRI research scans, these methods can reduce head motion in certain groups, but investigators must keep in mind the effects on functional MRI data.

Objective We developed a novel method to map behavioral effects of deep brain stimulation (DBS) across a 3D brain region and to assign statistical significance after stringent Type I error correction. This method was applied to behavioral changes in Parkinson disease (PD) induced by subthalamic nucleus (STN) DBS to determine whether these responses depended on anatomical location of DBS. Method Fifty-one PD participants with STN DBS were evaluated off medication, with DBS off and during unilateral STN DBS with clinically optimized settings. Dependent variables included DBS-induced changes in Unified Parkinson Disease Rating Scale (UPDRS) subscores, kinematic measures of bradykinesia and rigidity, working memory, response inhibition, mood, anxiety, and akathisia. Weighted t-tests at each voxel produced p images showing where DBS most significantly affected each dependent variable based on outcomes of participants with nearby DBS. Finally, a permutation test computed the probability that this p image indicated significantly different responses based on stimulation site. Results Most motor variables improved with DBS anywhere in the STN region, but several motor, cognitive and affective responses significantly depended on precise location stimulated, with peak p values in superior STN/zona incerta (quantified bradykinesia), dorsal STN (mood, anxiety), and inferior STN/substantia nigra (UPDRS tremor, working memory). Interpretation Our method identified DBS-induced behavioral changes that depended significantly on DBS site. These results do not support complete functional segregation within STN, since movement improved with DBS throughout, and mood improved with dorsal STN DBS. Rather, findings support functional convergence of motor, cognitive and limbic information in STN.