Introduction: Chronic pain is a major public health concern, as is the associated use of opioid medications, highlighting the importance of alternative treatments, such as spinal cord stimulation (SCS). Here, we present the final 24-month results of the Avalon study, which investigated the use of the first closed-loop SCS system in patients with chronic pain. The system measures the evoked compound action potentials (ECAPs) elicited by each stimulus pulse and drives a feedback loop to maintain the ECAP amplitude near constant.
View Article and Find Full Text PDFCorona virus outbreak started in December 2019, and the disease has been defined by the World Health Organization as a public health emergency. Coronavirus is a source of deep venous thrombosis (DVT) due to complications such as over-coagulation, blood stasis, and endothelial damage. In this study, we report a 26-year-old pregnant woman with coronavirus who was hospitalized with a right ovarian vein thrombosis at Besat Hospital in Sanandaj.
View Article and Find Full Text PDFBackground: Spinal cord stimulation (SCS) activates the dorsal column fibers using electrical stimuli. Current SCS systems function in fixed-output mode, delivering the same stimulus regardless of spinal cord (SC) activation.
Objective: To present long-term outcomes of a novel closed-loop SCS system that aims to maintain the SC activation near a set target level and within a therapeutic window for each patient.
Introduction: The electrically evoked compound action potential (ECAP) is a measure of the response from a population of fibers to an electrical stimulus. ECAPs can be assessed during spinal cord stimulation (SCS) to elucidate the relationship between stimulation, electrophysiological response, and neuromodulation. This has consequences for the design and programming of SCS devices.
View Article and Find Full Text PDFObjectives: Conventional spinal cord stimulation (SCS) delivers a fixed-input of energy into the dorsal column. Physiologic effects such as heartbeat, respiration, spinal cord movement, and history of stimulation can cause both the perceived intensity and recruitment of stimulation to increase or decrease, with clinical consequences. A new SCS system controls stimulation dose by measuring the recruitment of fibers in the dorsal column and by using the amplitude of the evoked compound action potentials (ECAPs) to maintain stimulation within an individualized therapeutic range.
View Article and Find Full Text PDFMany neurons in mammalian primary visual cortex have properties such as sharp tuning for contour orientation, strong selectivity for motion direction, and insensitivity to stimulus polarity, that are not shared with their sub-cortical counterparts. Successful models have been developed for a number of these properties but in one case, direction selectivity, there is no consensus about underlying mechanisms. We here define a model that accounts for many of the empirical observations concerning direction selectivity.
View Article and Find Full Text PDFBilateral PPG signals have been used for comparative study of two groups of healthy (free from any cardiovascular risk factors) and diabetic (as cardiovascular disease risk group) subjects in the age-matched range 40-50 years. The peripheral blood pulsations were recorded simultaneously from right and left index fingers for 90 s. Pulses have been modeled with the ARX440 model in the interval of 300 sample points with 100 sample points overlap between segments.
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