Evidence map›Paper›PMID 41077979›Full record

ArticleNeurospine2025

Chiari Malformation and Hindbrain Descent: Characterization and New Classification Based on Mechanism and Pathogenesis, and Surgical Management.

Misao Nishikawa, Paolo A Bolognese, Masaki Yoshimura, Kentarou Naito, Noritsugu Kunihiro, Hiromichi Ikuno, Mitsuhiro Hara, Hiroaki Sakamoto, Kenji Ohata, Takeo Goto

Abstract read
In one paragraph

Article in Neurospine, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

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

What it found

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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

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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

1 citing paper in PubMed.

  1. 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

10 authors.

Misao NishikawaDepartment of Neurosurgery, Moriguchi Ikuno Memorial Hospital, Moriguchi, Japan.
Paolo A BologneseChiari EDS Center, Mount Sainai South Nassou University Hospital, Oceanside, NY, USA.
Masaki YoshimuraDepartment Neurosurgery, Tokusyukai Yao General Hospital, Yao, Japan.
Kentarou NaitoDepartment of Neurosurgery, Osaka Metropolitan University Hospital, Osaka, Japan.
Noritsugu KunihiroDepartment of Pediatric Neurosurgery, Osaka City General Hospital, Osaka, Japan.
Hiromichi IkunoDepartment of Neuroradiology, Moriguchi Ikuno Memorial Hospital, Osaka, Japan.
Mitsuhiro HaraDepartment of Neurology, Moriguchi Ikuno Memorial Hospital, Osaka, Japan.
Hiroaki SakamotoDepartment of Pediatric Neurosurgery, Osaka City General Hospital, Osaka, Japan.
Kenji OhataDepartment of Neurosurgery, Naniwa Ikuno Hospital, Osaka, Japan.
Takeo GotoDepartment of Neurosurgery, Osaka Metropolitan University Hospital, Osaka, Japan.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

H. Chiari described 4 types of abnormal development of the posterior fossa, which were subsequently classified as Chiari malformation types I, II, III, and IV. Many issues in neurosurgery concerning classification and surgical management are without evolving concepts. This review aims to clarify the mechanisms and pathogenesis underlying hindbrain (the brain stem and cerebellum) descent, classify them accordingly, and discuss appropriate surgical management. We propose a classification of 4 independent pathogenic mechanisms: (1) constriction in the posterior cranial fossa (PCF) due to underdevelopment of the occipital bone; (2) enlargement of hindbrain; and (3) traction caused by tethering lesions. We examine the pathogenesis of hindbrain descent from embryological perspectives and neuroradiological findings, with a particular focus on lesser-known mechanisms. Additionally, another fourth mechanism is proposed: (4) instability at the craniocervical junction. We suggest a novel classification for Chiari malformation type I based on the underlying pathogenesis, guided by morphometric (occipital bone size) and volumetric (PCF volume) analyses. Furthermore, it delves deeper into their pathogenesis by drawing on insights from developmental biology, genetic studies, and experimental research. Surgical management is tailored to the underlying mechanism, and we proposed the algorithm for decision of surgical intervention. For crowding of the PCF due to underdevelopment of the occipital bone, posterior fossa decompression is the appropriate surgical intervention. For craniocervical instability, occipitocervical fixation is recommended. We also review the recent literature on surgical outcomes associated with each treatment approach. Finally, we highlight current genetic research related to the pathogenesis of hindbrain descent.

Indexed as

Chiari malformationClassificationGenetic researchPathogenesisSurgical managementTonsillar herniation

Identifiers

PMID41077979
PMCPMC12518898

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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.