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Substernal goitre is characterised by compressive symptoms of the airway and oesophagus. Chronic, progressive symptoms usually result in surgical removal. We report a rare presentation of substernal goitre in a male in his early 70s who suffered from severe bilateral lower extremity (LE) lymphoedema, resulting in immobility and nursing home placement, and left upper extremity lymphoedema. Our initial assessment led to a filariasis work-up, which was negative, due to the patient’s prior 2-year residence in India and service overseas. Chest CT scan revealed an incidental substernal goitre extending posterior to the left innominate vein and aortic arch to the level of the left mainstem bronchus. The patient underwent a left hemithyroidectomy via cervical excision and sternotomy and had an uneventful recovery with resolution of lymphoedema and mobility. Despite extensive literature regarding clinical presentations of substernal goitre, severe lymphoedema of the LE is not a well-established association.

BackgroundFollowing mild traumatic brain injury (mTBI) compromised white matter structural integrity can result in alterations in functional connectivity of large-scale brain networks and may manifest in functional deficit including cognitive dysfunction. Advanced magnetic resonance neuroimaging techniques, specifically diffusion tensor imaging (DTI) and resting state functional magnetic resonance imaging (rs-fMRI), have demonstrated an increased sensitivity for detecting microstructural changes associated with mTBI. Identification of novel imaging biomarkers can facilitate early detection of these changes for effective treatment. In this study, we hypothesize that feature selection combining both structural and functional connectivity increases classification accuracy.Methods16 subjects with mTBI and 20 healthy controls underwent both DTI and resting state functional imaging. Structural connectivity matrices were generated from white matter tractography from DTI sequences. Functional connectivity was measured through pairwise correlations of rs-fMRI between brain regions. Features from both DTI and rs-fMRI were selected by identifying five brain regions with the largest group differences and were used to classify the generated functional and structural connectivity matrices, respectively. Classification was performed using linear support vector machines and validated with leave-one-out cross validation.ResultsGroup comparisons revealed increased functional connectivity in the temporal lobe and cerebellum as well as decreased structural connectivity in the temporal lobe. After training on structural connections only, a maximum classification accuracy of 78% was achieved when structural connections were selected based on their corresponding functional connectivity group differences. After training on functional connections only, a maximum classification accuracy of 69% was achieved when functional connections were selected based on their structural connectivity group differences. After training on both structural and functional connections, a maximum classification accuracy of 69% was achieved when connections were selected based on their structural connectivity.ConclusionsOur multimodal approach to ROI selection achieves at highest, a classification accuracy of 78%. Our results also implicate the temporal lobe in the pathophysiology of mTBI. Our findings suggest that white matter tractography can serve as a robust biomarker for mTBI when used in tandem with resting state functional connectivity.