Evidence map›Paper›PMID 40372349›Full record

ArticleEpilepsia2025

No association between histopathology and neurophysiology in surgical specimens from pediatric focal epilepsy patients.

Nicolás von Ellenrieder, Mariam Alrashid, Kenneth Myers, Bradley Osterman, Elisabeth Simard-Tremblay, Jason Karamchandani, Marie-Christine Guiot, Jean Gotman, Roy W R Dudley

Abstract read
In one paragraph

Article in Epilepsia, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. Internal and external validation of comprehensive high-frequency activity biomarkers for epilepsy surgery.Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology · 2026
    Article
  2. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

9 authors.

Nicolás von EllenriederMontreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada.ORCID https://orcid.org/0000-0003-0845-347X
Mariam AlrashidDepartment of Neurosurgery, King Fahd Hospital of the University, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia.
Kenneth MyersChild Health and Human Development Program, Research Institute of McGill University Health Centre, Montreal, Quebec, Canada.
Bradley OstermanDivision of Neurology, Department of Pediatrics, Montreal Children's Hospital, Montreal, Quebec, Canada.
Elisabeth Simard-TremblayDivision of Neurology, Department of Pediatrics, Montreal Children's Hospital, Montreal, Quebec, Canada.
Jason KaramchandaniMontreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada.
Marie-Christine GuiotMontreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada.
Jean GotmanMontreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada.
Roy W R DudleyChild Health and Human Development Program, Research Institute of McGill University Health Centre, Montreal, Quebec, Canada.

Funding

CIHR 487052CIHR FDN 143208Fonds de Recherche du Quebec - SantéThe Foundation of the Department of Neurosurgery, McGill University
6 · The paper itself

Abstract

objectiveFocal epilepsy is caused by focal brain pathologies sometimes with involvement of surrounding or distant tissue. However, within the epileptogenic zone (EZ), which can be resected to cure epilepsy, the contribution of histopathological cells to epileptogenicity remains unknown. We hypothesized that areas showing neurophysiological biomarkers of epileptogenicity would more often contain histopathological cells compared to areas without such biomarkers.

methodsPediatric epilepsy patients with nonlesional magnetic resonance imaging (MRI), or with lesions with unclear borders, underwent stereoelectroencephalographic (SEEG) exploration followed by resective surgery of the suspected EZ. Tissue specimens were taken from locations where the SEEG contacts had been, using intraoperative MRI-guided precise neuronavigation. Then, we explored the association between histopathology and rates of interictal epileptic discharges, ripples, and fast ripples (FRs), and the channels of the seizure onset zone (SOZ).

resultsThe association between histopathology and ictal/interictal activity was low and not statistically significant in 260 specimens from 20 surgeries. Rates of interictal events were slightly lower for pathological samples than in normal tissue (low effect size, Cliff |d| < .15, p > .1). The classification accuracy of tissue as normal or pathological based on interictal activity/SOZ was low (accuracy ≤ 54%). As a secondary outcome, SEEG events were excellent predictors of surgical outcome, FRs leading to perfect prediction (20/20). SIGNIFICANCE: Histopathological tissue initiates epileptogenicity in focal epilepsy. However, our findings suggest that the EZ is not strictly a histopathological entity but a hybrid of abnormal cells and normal-appearing cells. Thus, SEEG events are biomarkers of epileptogenicity and not histopathology. Resecting of electrophysiological biomarkers of epileptogenicity may be more important than resecting all histopathology.

Indexed as

BrainEpilepsies, PartialAdolescentChildChild, PreschoolElectroencephalographyFemaleHumansMagnetic Resonance ImagingMaleNeuronavigationfast rippleshistopathologyintracranial EEGresective surgery

Identifiers

PMID40372349
PMCPMC12455368

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.