Design and validation of a surface-contact electrode for gastric pacing and concurrent slow-wave mapping

2021 ◽  
pp. 1-1
Author(s):  
Saeed Alighaleh ◽  
Leo K Cheng ◽  
Timothy R. Angeli ◽  
Zahra Aghababaie ◽  
Gregory O'Grady ◽  
...  
Keyword(s):  
Slow Wave ◽  
Gastric Pacing ◽  
Surface Contact ◽  
Contact Electrode

scholarly journals High-resolution entrainment mapping of gastric pacing: a new analytical tool

2010 ◽  
Vol 298 (2) ◽  
pp. G314-G321 ◽  
Author(s):  
Gregory O'Grady ◽  
Peng Du ◽  
Wim J. E. P. Lammers ◽  
John U. Egbuji ◽  
Pulasthi Mithraratne ◽  
...  
Keyword(s):  
High Resolution ◽  
Slow Wave ◽  
Wave Activity ◽  
Slow Wave Activity ◽  
Field Analysis ◽  
Research Progress ◽  
Multielectrode Arrays ◽  
Gastric Pacing ◽  
Improve Symptom ◽  
Accurate Quantification

Gastric pacing has been investigated as a potential treatment for gastroparesis. New pacing protocols are required to improve symptom and motility outcomes; however, research progress has been constrained by a limited understanding of the effects of electrical stimulation on slow-wave activity. This study introduces high-resolution (HR) “entrainment mapping” for the analysis of gastric pacing and presents four demonstrations. Gastric pacing was initiated in a porcine model (typical amplitude 4 mA, pulse width 400 ms, period 17 s). Entrainment mapping was performed using flexible multielectrode arrays (≤192 electrodes; 92 cm2) and was analyzed using novel software methods. In the first demonstration, entrainment onset was quantified over successive waves in spatiotemporal detail. In the second demonstration, slow-wave velocity was accurately determined with HR field analysis, and paced propagation was found to be anisotropic (longitudinal 2.6 ± 1.7 vs. circumferential 4.5 ± 0.6 mm/s; P < 0.001). In the third demonstration, a dysrhythmic episode that occurred during pacing was mapped in HR, revealing an ectopic slow-wave focus and uncoupled propagations. In the fourth demonstration, differences were observed between paced and native slow-wave amplitudes (0.24 ± 0.08 vs. 0.38 ± 0.14 mV; P < 0.001), velocities (6.2 ± 2.8 vs. 11.5 ± 4.7 mm/s; P < 0.001), and activated areas (20.6 ± 1.9 vs. 32.8 ± 2.6 cm2; P < 0.001). Entrainment mapping enables an accurate quantification of the effects of gastric pacing on slow-wave activity, offering an improved method to assess whether pacing protocols are likely to achieve physiologically and clinically useful outcomes.

Effects of pacing parameters on entrainment of gastric slow waves in patients with gastroparesis

1998 ◽  
Vol 274 (1) ◽  
pp. G186-G191 ◽  
Author(s):  
Z. Y. Lin ◽  
R. W. McCallum ◽  
B. D. Schirmer ◽  
J. D. Z. Chen
Keyword(s):  
Slow Wave ◽  
Pulse Width ◽  
Cardiac Pacing ◽  
Slow Waves ◽  
Effective Parameters ◽  
Gastric Pacing ◽  
Gastric Slow Wave ◽  
Gastric Slow Waves ◽  
Baseline Recording ◽  
Ectopic Pacemaker

The aim of this study was to investigate the effect of pacing parameters on the entrainment of gastric slow waves in patients with gastroparesis. Four pairs of cardiac pacing wires were placed on the serosal surface of the stomach in 13 patients with gastroparesis. After a baseline recording for 30 min, gastric pacing was performed in a number of sessions with different effective parameters, each lasting for 30 min. The following parameters were found to be effective for the entrainment of the gastric slow wave: a pacing frequency 10% higher than the intrinsic gastric slow wave frequency (IGF), 300 ms pulse width, and 4 mA pacing amplitude. A reduction of pacing amplitude from 4 to 2 mA and 1 mA reduced the percentage of entrainment of the gastric slow wave to 79 ± 10% and 50 ± 11%, respectively. Pacing with a pulse width of 30 or 3 ms was not able to entrain the gastric slow wave in any of the patients. An ectopic pacemaker of tachygastria found in three patients was reversed with gastric pacing. It was concluded that gastric pacing at a frequency up to 10% higher than the IGF and with an amplitude of 4 mA and a pulse width of 300 ms is able to completely entrain the gastric slow wave and normalize gastric dysrhythmias in patients with gastroparesis.

Sa1640 NONINVASIVE MEASUREMENT OF SMALL BOWEL SLOW WAVE ACTIVITY IN NEONATES - A PILOT STUDY

2020 ◽  
Vol 158 (6) ◽  
pp. S-364
Author(s):  
Suseela Somarajan ◽  
Nicole D. Muszynski ◽  
Aurelia s. Monk ◽  
Joseph D. Olson ◽  
Alexandra Russell ◽  
...  
Keyword(s):  
Pilot Study ◽  
Small Bowel ◽  
Slow Wave ◽  
Wave Activity ◽  
Slow Wave Activity ◽  
Noninvasive Measurement

Face and Word Recognition in Patients with Left and Right Hemispheric Lesions: Evidence from Reaction Times and ERPs

2002 ◽  
Vol 13 (1) ◽  
pp. 69-83 ◽  
Author(s):  
Stefan R. Schweinberger ◽  
Thomas Klos ◽  
Werner Sommer
Keyword(s):  
Slow Wave ◽  
Reaction Times ◽  
Memory Search ◽  
Event Related Potentials ◽  
Performance Deficits ◽  
Set Size ◽  
Left Brain ◽  
Related Potentials ◽  
Abstract Words ◽  
Left Brain Damage

Abstract: We recorded reaction times (RTs) and event-related potentials (ERPs) in patients with unilateral lesions during a memory search task. Participants memorized faces or abstract words, which were then recognized among new ones. The RT deficit found in patients with left brain damage (LBD) for words increased with memory set size, suggesting that their problem relates to memory search. In contrast, the RT deficit found in patients with RBD for faces was apparently related to perceptual encoding, a conclusion also supported by their reduced P100 ERP component. A late slow wave (720-1720 ms) was enhanced in patients, particularly to words in patients with LBD, and to faces in patients with RBD. Thus, the slow wave was largest in the conditions with most pronounced performance deficits, suggesting that it reflects deficit-related resource recruitment.

Slow Wave Activity Related to Working Memory Maintenance in the N-Back Task

2016 ◽  
Vol 30 (4) ◽  
pp. 141-154 ◽  
Author(s):  
Kira Bailey ◽  
Gregory Mlynarczyk ◽  
Robert West
Keyword(s):  
Working Memory ◽  
Slow Wave ◽  
Time Course ◽  
Relevant Information ◽  
Wave Activity ◽  
Slow Wave Activity ◽  
Response Accuracy ◽  
Functional Neuroanatomy ◽  
Stimulus Interval ◽  
Back Task

Abstract. Working memory supports our ability to maintain goal-relevant information that guides cognition in the face of distraction or competing tasks. The N-back task has been widely used in cognitive neuroscience to examine the functional neuroanatomy of working memory. Fewer studies have capitalized on the temporal resolution of event-related brain potentials (ERPs) to examine the time course of neural activity in the N-back task. The primary goal of the current study was to characterize slow wave activity observed in the response-to-stimulus interval in the N-back task that may be related to maintenance of information between trials in the task. In three experiments, we examined the effects of N-back load, interference, and response accuracy on the amplitude of the P3b following stimulus onset and slow wave activity elicited in the response-to-stimulus interval. Consistent with previous research, the amplitude of the P3b decreased as N-back load increased. Slow wave activity over the frontal and posterior regions of the scalp was sensitive to N-back load and was insensitive to interference or response accuracy. Together these findings lead to the suggestion that slow wave activity observed in the response-to-stimulus interval is related to the maintenance of information between trials in the 1-back task.

Is a frontal positive slow wave in the ERP specific for emotion-focused processing?

1996 ◽  
Author(s):  
Stefanie Maier ◽  
Oliver Diedrich ◽  
Gabriele Becker ◽  
Ewald Naumann ◽  
Dieter Bartussek
Keyword(s):  
Slow Wave ◽  
Focused Processing

Therapieschwierige Epilepsien am Beispiel der Rasmussen-Enzephalitis

2012 ◽  
Vol 12 (06) ◽  
pp. 368-370
Author(s):  
A. Merkenschlager ◽  
I. Sorge ◽  
A. Bertsche ◽  
M. K. Bernhard ◽  
F. Wegmann
Keyword(s):  
Slow Wave ◽  
Psychische Belastung ◽  
Sich Eine ◽  
Neurologische Defizite

Zusammenfassung Einleitung: Bis zu einem Drittel der Epilepsiepatienten leidet unter einer therapieschwierigen Epilepsie. Dies bedeutet eine erhebliche Belastung im Alltag, zudem können neurologische Defizite resultieren. Wieso die Patienten nicht auf die vorhandenen Therapieoptionen ansprechen, ist noch weitestgehend unklar. Die Rasmussen-Enzephalitis (RE) ist ein Beispiel für eine therapieschwierige Epilepsie. Fallbericht: Nach unauffälliger motorischer und sprachlicher Entwicklung traten im Alter von 6 Jahren bei dem Mädchen das erste Mal fokale und komplex-fokale Krampfanfälle auf. Auch unter antikonvulsiver Polytherapie konnte eine Anfallsfreiheit nicht erreicht werden. Zudem entwickelte sich eine über viele Jahre progrediente Hemiatrophia cerebri, und es zeigten sich einseitig betonte epilepsietypische EEG-Muster mit Verlangsamungen und sharp-slow-wave-Komplexen. In Zusammenschau dieser Befunde konnte die Diagnose einer Rasmussen-Enzephalitis gestellt werden. Repetitive Stoßtherapien mit Methylprednisolon und Immunglobulinen brachten kurzfristig eine Linderung der Krampfsituation, die neurologischen Defizite und die daraus resultierende enorme psychische Belastung waren jedoch progredient. Diskussion: Am ehesten wird von einer autoimmunen Reaktion als Ursache der Rasmussen Enzephalitis ausgegangen. Ein optimales medikamentöses Therapieschema dieser Epilepsie gibt es bis heute nicht. Eine frühzeitige Diagnosestellung und sofortiger Therapiebeginn lassen die Krankheit jedoch meist langsamer und weniger schwerwiegend voranschreiten. Einzig die Hemisphärektomie bringt in bis zu 85 % der Fälle eine Anfallsfreiheit. Die damit einhergehende spastische Hemiparese, Hemianopsie sowie Sprachstörungen lassen die Entscheidung zur Operation jedoch schwer fallen. Gemeinsam mit dem Patienten und seiner Familie muss eine sorgfältige Risiko-NutzenAbwägung erfolgen.

Sign in / Sign up

Export Citation Format

Share Document