Featured Research

from universities, journals, and other organizations

Fast ripples confirmed to be valuable biomarker of area responsible for seizure activity in children

Date:
July 30, 2011
Source:
Wiley-Blackwell
Summary:
New research focusing on high-frequency oscillations, termed ripples and fast ripples, recorded by intracranial electroencephalography, may provide an important marker for the localization of the brain region responsible for seizure activity. According to the study the resection of brain regions containing fast ripples, along with the visually-identified seizure-onset zone, may achieve a good seizure outcome in pediatric epilepsy.

New research focusing on high-frequency oscillations, termed ripples and fast ripples, recorded by intracranial electroencephalography (EEG), may provide an important marker for the localization of the brain region responsible for seizure activity. According to the study now available in Epilepsia, a journal of the International League Against Epilepsy (ILAE), the resection of brain regions containing fast ripples, along with the visually-identified seizure-onset zone, may achieve a good seizure outcome in pediatric epilepsy.

High-frequency oscillations at 80-200 Hz are known as ripples and those above 200 Hz are considered fast ripples. Medical evidence suggests that fast ripples are a specific surrogate marker of the seizure generation zone. Studies in adults have suggested that resection of the brain region containing fast ripples was associated with good seizure outcome. However, these studies used a small number of electrode (EEG) contacts, with limited brain coverage, which may not be optimal for pediatric patients who often exhibit a more generalized epileptic network than adults.

Hiroshi Otsubo, MD, with The Hospital for Sick Children in Toronto, Canada and lead researcher of the current study explains, "In pediatric patients, extensive surgical resection are often used, but may overestimate the link between high-frequency oscillations and seizure outcome. Good surgical success may also be achieved by more limited surgeries that include both the brain region with high-frequency oscillations and the brain region that appears to initiate seizures, even when they are independent." To further explore this hypothesis, the research team evaluated the relationship of resection of brain regions containing high-frequency oscillations and the area of seizure onset in pediatric epilepsy patients.

Researchers retrospectively analyzed 28 pediatric patients with epilepsy who underwent intracranial EEG monitoring prior to focal resection surgery. Brain regions containing a high occurrence of high-frequency oscillations were determined, and spatial relationships between regions with fast ripples and seizure-onset zones were investigated. The team compared seizure outcome with the size of these regions, the surgical resection, and amount of the regions with fast ripples and areas of seizure onset within the resection area.

Results show that 2 years after surgery, 10 patients were completely seizure free and 18 continued to have some seizure activity. Complete resection of the brain regions exhibiting fast ripples was significantly associated with better seizure outcome. Improved seizure outcome was also observed with complete resection of brain regions with ripples; surprisingly, however, resection of the area of seizure onset did not correlate with seizure outcome. The size of surgical resection was not linked to seizure outcome.

Furthermore, the authors, Drs. Akiyama and Otsubo et al., noted that the visually- determined seizure onset zone partially overlapped with regions containing high-rate fast ripples. "The entire epileptic network, containing fast ripples, ripples and seizure onset zones, must be thoroughly analyzed to ensure complete resection of the area causing seizures with the smallest resection possible," advised Drs. Akiyama and Otsubo et al. "While our results are preliminary and further validation is necessary, the analysis of high frequency oscillations offers clinicians a new surgical approach that could potentially improve seizure outcome in children with epilepsy."


Story Source:

The above story is based on materials provided by Wiley-Blackwell. Note: Materials may be edited for content and length.


Journal Reference:

  1. Tomoyuki Akiyama, Blαthnaid McCoy, Cristina Y. Go, Ayako Ochi, Irene M. Elliott, Mari Akiyama, Elizabeth J. Donner, Shelly K. Weiss, O. Carter Snead, James T. Rutka, James M. Drake, Hiroshi Otsubo. Focal resection of fast ripples on extraoperative intracranial EEG improves seizure outcome in pediatric epilepsy. Epilepsia, 2011; DOI: 10.1111/j.1528-1167.2011.03199.x

Cite This Page:

Wiley-Blackwell. "Fast ripples confirmed to be valuable biomarker of area responsible for seizure activity in children." ScienceDaily. ScienceDaily, 30 July 2011. <www.sciencedaily.com/releases/2011/07/110729175353.htm>.
Wiley-Blackwell. (2011, July 30). Fast ripples confirmed to be valuable biomarker of area responsible for seizure activity in children. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2011/07/110729175353.htm
Wiley-Blackwell. "Fast ripples confirmed to be valuable biomarker of area responsible for seizure activity in children." ScienceDaily. www.sciencedaily.com/releases/2011/07/110729175353.htm (accessed October 20, 2014).

Share This



More Health & Medicine News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Microneedle Patch Promises Painless Pricks

Microneedle Patch Promises Painless Pricks

Reuters - Innovations Video Online (Oct. 18, 2014) — Researchers at The National University of Singapore have invented a new microneedle patch that could offer a faster and less painful delivery of drugs such as insulin and painkillers. Video provided by Reuters
Powered by NewsLook.com
Raw: Nurse Nina Pham Arrives in Maryland

Raw: Nurse Nina Pham Arrives in Maryland

AP (Oct. 17, 2014) — The first nurse to be diagnosed with Ebola at a Dallas hospital walked down the stairs of an executive jet into an ambulance at an airport in Frederick, Maryland, on Thursday. Pham will be treated at the National Institutes of Health. (Oct. 16) Video provided by AP
Powered by NewsLook.com
Raw: Cruise Ship Returns to US Over Ebola Fears

Raw: Cruise Ship Returns to US Over Ebola Fears

AP (Oct. 17, 2014) — A Caribbean cruise ship carrying a Dallas health care worker who is being monitored for signs of the Ebola virus is heading back to Texas, US, after being refused permission to dock in Cozumel, Mexico. (Oct. 17) Video provided by AP
Powered by NewsLook.com
Spanish Govt: Four Suspected Ebola Cases in Spain Test Negative

Spanish Govt: Four Suspected Ebola Cases in Spain Test Negative

AFP (Oct. 17, 2014) — All four suspected Ebola cases admitted to hospitals in Spain on Thursday have tested negative for the deadly virus in a first round of tests, the government said Friday. Duration: 00:55 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins