High-Frequency Intermuscular Coherence between Arm Muscles during Robot-Mediated Motor Adaptation.
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ABSTRACT:
SUBMITTER: Pizzamiglio S
PROVIDER: S-EPMC5220015 | biostudies-literature | 2016
REPOSITORIES: biostudies-literature
Publications
High-Frequency Intermuscular Coherence between Arm Muscles during Robot-Mediated Motor Adaptation.
Pizzamiglio Sara S De Lillo Martina M Naeem Usman U Abdalla Hassan H Turner Duncan L DL
Frontiers in physiology 20170109
Adaptation of arm reaching in a novel force field involves co-contraction of upper limb muscles, but it is not known how the co-ordination of multiple muscle activation is orchestrated. We have used intermuscular coherence (IMC) to test whether a coherent intermuscular coupling between muscle pairs is responsible for novel patterns of activation during adaptation of reaching in a force field. Subjects (<i>N</i> = 16) performed reaching trials during a null force field, then during a velocity-dep ...[more]
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Project description:BackgroundHigh-frequency optical coherence tomography (HF-OCT) is an intra-vascular imaging technique capable of assessing device-vessel interactions at spatial resolution approaching 10 µm. We tested the hypothesis that adequately deployed Woven EndoBridge (WEB) devices as visualized by HF-OCT lead to higher aneurysm occlusion rates.MethodsIn a leporine model, elastase-induced aneurysms (n=24) were treated with the WEB device. HF-OCT and digital subtraction angiography (DSA) were performed following WEB deployment and repeated at 4, 8, and 12 weeks. Protrusion (0-present, 1-absent) and malapposition (0-malapposed, 1-neck apposition >50%) were binary coded. A device was considered 'adequately deployed' by HF-OCT and DSA if apposed and non-protruding. Aneurysm healing on DSA was reported using the 4-point WEB occlusion score: A or B grades were considered positive outcome. Neointimal coverage was quantified on HF-OCT images at 12 weeks and compared with scanning electron microscopy (SEM).ResultsAdequate deployment on HF-OCT correlated with positive outcome (P=0.007), but no statistically significant relationship was found between good outcome and adequate deployment on DSA (P=0.289). Absence of protrusion on HF-OCT correlated with a positive outcome (P=0.006); however, malapposition alone had no significant relationship (P=0.19). HF-OCT showed a strong correlation with SEM for the assessment of areas of neointimal tissue (R²=0.96; P<0.001). More neointimal coverage of 78%±32% was found on 'adequate deployment' cases versus 31%±24% for the 'inadequate deployment' cases (P=0.001).ConclusionHF-OCT visualizes features that can determine adequate device deployment to prognosticate early aneurysm occlusion following WEB implantation and can be used to longitudinally monitor aneurysm healing progression.
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