Publications by authors named "Sean Downs"

Article Synopsis
  • The study addresses the challenges in diagnosing small-fiber neuropathy (SFN) due to its subjective nature and limited testing options, leading to the creation of the Massachusetts General Hospital Neuropathy Exam Tool (MAGNET) to enhance diagnostic accuracy.
  • Researchers assessed MAGNET’s performance on 160 symptomatic patients and 37 healthy volunteers, comparing various physical examination findings against objective SFN tests, such as skin biopsies and autonomic function tests.
  • The results demonstrated strong reliability and predictive accuracy for MAGNET, achieving 80%-85% accuracy in identifying patients with SFN, particularly highlighting reduced pin sharpness sensitivity in toes as a common abnormality.
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Patients with implanted medical devices such as deep brain stimulation or spinal cord stimulation are often unable to receive magnetic resonance imaging (MRI). This is because once the device is within the radiofrequency (RF) field of the MRI scanner, electrically conductive leads act as antenna, amplifying the RF energy deposition in the tissue and causing possible excessive tissue heating. Here we propose a novel concept in lead design in which 40cm lead wires are coated with a ~1.

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Patients with deep brain stimulation (DBS) implants can significantly benefit from magnetic resonance imaging (MRI), however access to MRI is restricted in these patients because of safety concerns due to RF heating of the leads. Recently we introduced a patient-adjustable reconfigurable transmit coil for low-SAR imaging of DBS at 1.5T.

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Access to MRI is limited for patients with deep brain stimulation (DBS) implants due to safety hazards, including radiofrequency (RF) heating of tissue surrounding the leads. Computational models provide an exquisite tool to explore the multi-variate problem of RF heating and help better understand the interaction of electromagnetic fields and biological tissues. This paper presents a computational approach to assess RF-induced heating, in terms of specific absorption rate (SAR) in the tissue, around the tip of bilateral DBS leads during MRI at 64MHz/1.

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