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• Subcortical band heterotopia can create disruptions to white matter tracts. • Diffusion tensor imaging may show disruptions to visualized white matter tracts. • Tissue pathology shows correlating heterotopic infiltration of the white matter. [ABSTRACT FROM AUTHOR]

Background: Prophylactic central lymph node dissection with total thyroidectomy (TT) for the treatment of papillary thyroid cancer (PTC) is controversial because of the possibility of increased morbidity with uncertain benefit. The purpose of this study is to determine whether prophylactic central neck dissection provides any advantages over TT alone. Methods: Retrospective cohort study of patients with PTC without preoperative evidence of lymph node involvement undergoing either TT or TT with bilateral central lymph node dissection (TT + BCLND). Results: From 2002 to 2009, 143 patients with clinically node-negative PTC underwent either TT (n = 65) or TT + BCLND (n = 78). The groups were similar in age, gender, tumor size, multifocality, angioinvasion, and metastasis/age/completeness-of-resection/invasion/size score. The presence of involved central neck lymph nodes upstaged 28.6% of patients in the TT + BCLND group to stage III disease, which resulted in higher radioactive iodine ablation doses. Stimulated serum thyroglobulin levels and the number of patients with undetectable stimulated thyroglobulin levels before and 1 year after radioactive iodine ablation were equivalent. Conclusion: The addition of routine central lymph node dissection to TT for the treatment of PTC upstages nearly one third of patients over the age of 45 thereby changing the dose of radioactive iodine ablative therapy, but does not change postoperative thyroglobulin levels after completion of radioiodine treatment. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to evaluate Meyer''s loop by 3-T MRI with fiber tractography, color-coded fractional anisotropy maps, and eigenvector maps. The anteroposterior distance from the anterior bundle of the Meyer''s loop to temporal pole ranged from 26.3 to 34 mm, overlapping with the previously published anatomical dissection studies. Diffusion tensor imaging with fiber tractography, color-coded FA maps, and color maps of the principal eigenvector at 3 T appear to be promising techniques for the virtual dissection of Meyer''s loop. [Copyright &y& Elsevier]

Abstract: Apparent diffusion coefficients (ADCs) of the brain lesions in primary angiitis of the central nervous system (PACNS) patients were analyzed in this study. The mean ADC ratios for acute/subacute phase lesions were significantly lower than that for chronic phase lesions. However, some acute/subacute phase lesions had elevated ADCs and these lesions disappeared overtime, implicating a nonischemic mechanism in PACNS. [Copyright &y& Elsevier]

Background: Surgical treatment of primary hyperaldosteronism (PHA) requires demonstration of unilateral adrenal hypersecretion. Optimal methods for interpretation of imaging and invasive testing are still in development. Methods: A retrospective review from 1996–2007 of 106 patients with PHA was undertaken. Patient demographics, biochemical studies, radiologic imaging, operative reports, and pathology were reviewed and comparisons made. Optimal ratios for adrenal vein sampling were tested with regard to sensitivity and specificity. Preoperative and postoperative medication requirements and blood pressures were compared among different treatment groups. Results: Seventy-eight patients (62 surgically treated) met criteria for inclusion. Median arterial blood pressure at diagnosis was 150/86 mm Hg while taking 3 antihypertensive medications. 69.2% required potassium supplementation. Median aldosterone:renin ratio was 107.0. Forty-two AVS procedures changed the management of 15 patients (35.7%) when compared to CT results. AVS accuracy was 96.6 vs 88.9% for NP-59 scintigraphy. Operative patients remained on fewer antihypertensive medications (1 vs 3), and mean systolic pressure was lower (130 vs 146 mm Hg) compared with medically managed patients. Conclusion: When used together, pre-ACTH aldosterone ratios, normalized A/C:A/C ratios, ratios to define contralateral suppression, and post-ACTH stimulated values allowed for capture of episodically secreting tumors and subtle unilateral or bilateral hyperaldosteronism. [Copyright &y& Elsevier]

Abstract: This study retrospectively reviewed magnetic resonance images of 20 patients with sinonasal inflammatory diseases. Forty-four areas of sinonasal secretions were analyzed with correlation between the signal ratios on T2-weighted images and the diffusion-weighted imaging signal ratios or apparent diffusion coefficients (ADCs). ADCs decreased in direct proportion to the signal ratios on the T2-weighted images (P<.001, r=.56). Given the correlation between the ADCs and the physiological state of sinonasal secretions, ADCs may provide quantitative information useful to the diagnosis of sinonasal inflammatory disease. [Copyright &y& Elsevier]

Abstract: This retrospective study consisted of 17 consecutive patients with oligodendrogliomas. We qualitatively and quantitatively assessed the diagnostic value of fluid-attenuated inversion-recovery (FLAIR) images compared with T2-weighted fast spin-echo (FSE) images for evaluating intracranial oligodendrogliomas. Qualitative evaluations of signal intensity, tumor conspicuity, definition of tumor margin, distinction between solid and cystic-like parts within tumor, and calcification were performed. Quantitative criteria comparing FLAIR to T2-weighted FSE images included tumor-to-background contrast and contrast-to-noise ratio (CNR) and tumor-to-cerebrospinal fluid (CSF) contrast and CNR. Our results demonstrate that the FLAIR sequence can replace the T2-weighted FSE sequence for evaluating oligodendrogliomas. [Copyright &y& Elsevier]

Neurovascular spinal cord injuries are very prevalent and in a busy trauma center radiology practice these injuries are commonly seen. Imaging neurovascular injuries has been greatly facilitated by magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA). The histopathological changes that occur with spinal cord trauma have been found to correlate well with what is seen on MRI examinations. The MRI findings in spinal cord trauma have also been found to be useful in determining patient prognosis. Spinal cord infarcts due to arterial injury from trauma are relatively rare, but it has been shown by imaging that vertebral artery injuries are not an unusual occurrence. The specific findings associated with neurovascular injuries will be described with an emphasis on the findings on MRI and MRA examinations. MRI and MRA techniques have become the procedure of choice for evaluating neurovascular injuries because of their proven accuracy and because they are non-invasive. Conventional angiography, although, does remain quite useful for evaluating arterial injuries. [Copyright &y& Elsevier]

Abstract: The ability to attend to particular stimuli while ignoring others is crucial in goal-directed activities and has been linked with prefrontal cortical regions, including the dorsolateral prefrontal cortex (DLPFC). Both hyper- and hypo-activation in the DLPFC has been reported in patients with attention-deficit/hyperactivity disorder (ADHD) during many different cognitive tasks, but the network-level effects of such aberrant activity remain largely unknown. Using magnetoencephalography (MEG), we examined functional connectivity between regions of the DLPFC and the modality-specific auditory cortices during an auditory attention task in medicated and un-medicated adults with ADHD, and those without ADHD. Participants completed an attention task in two separate sessions (medicated/un-medicated), and each session consisted of two blocks (attend and no-attend). All MEG data were coregistered to structural MRI, corrected for head motion, and projected into source space. Subsequently, we computed the phase coherence (i.e., functional connectivity) between DLPFC regions and the auditory cortices. We found that un-medicated adults with ADHD exhibited greater phase coherence in the beta (14–30Hz) and gamma frequency (30–56Hz) range in attend and no-attend conditions compared to controls. Stimulant medication attenuated these differences, but did not fully eliminate them. These results suggest that aberrant bottom-up processing may engulf executive resources in ADHD. [Copyright &y& Elsevier]