Related Experiment Video
Updated: Jan 21, 2026
14:58
Comprehensive Endovascular and Open Surgical Management of Cerebral Arteriovenous Malformations
Published on: October 20, 2017
10.2K
Management of Chiari I malformations: a paradigm in evolution
H Alexander1,2, D Tsering1, J S Myseros1,3
1Division of Neurosurgery, Children's National Medical Center, Washington, DC, USA.
Summary
Management of Chiari I malformation (CM-I) in children is evolving. Extradural approaches show promise for successful outcomes with fewer complications, while less tonsillar manipulation is increasingly supported by evidence.
Area of Science:
- Neurosurgery
- Pediatric Neurology
- Craniovertebral Junction Abnormalities
Background:
- Chiari I malformation (CM-I) diagnosis and management remain complex, with ongoing debates regarding optimal surgical strategies and outcomes.
- Increasing diagnosis rates in pediatric populations, often as incidental findings in asymptomatic individuals, necessitate a clear understanding of management guidelines.
Purpose of the Study:
- To review current evidence and past experiences in the management of pediatric Chiari I malformations.
- To provide recommendations for future directions in the treatment of CM-I.
Main Methods:
- Comprehensive literature review on pediatric CM-I management.
- Analysis of 1073 pediatric patients diagnosed with CM-I between 1998 and 2018 at Children's National Medical Center.
- Comparison of surgical techniques, including bone-only posterior fossa decompression (PFD) versus PFD with duraplasty (PFDD), and tonsillar manipulation strategies.
Main Results:
- A trend towards earlier diagnosis of CM-I and increased rates of posterior fossa decompression surgery (PFD).
- No significant difference in outcomes between PFD and PFDD surgical approaches (p=0.59).
- Significantly better outcomes in patients who did not undergo tonsillar manipulation compared to those who did (p=0.02).
Conclusions:
- A shift towards extradural surgical approaches, such as dural delamination, is favored in pediatric CM-I due to high success rates and lower complication risks.
- The efficacy and necessity of tonsillar manipulation are increasingly questioned, with growing evidence supporting less invasive techniques.
Related Concept Videos
02:55The Evidence for Evolution
47.7K
Genetic variations accumulating within populations over generations give rise to biological evolution. Evolutionary changes can result in the formation of novel varieties and entire new species. These changes are responsible for the diverse forms of life inhabiting the planet. The evidence for evolution suggests that all living organisms descended from common ancestors.
47.7K
01:54Convergent Evolution
31.5K
Evolution shapes the features of organisms over time, ensuring that they are suited for the environments in which they live. Sometimes, selection pressure leads to the rise of similar but unrelated adaptations in organisms with no recent common ancestors, a process known as convergent evolution.
31.5K
01:24Eukaryotic Evolution
40.3K
The endosymbiont theory is the most widely accepted theory of eukaryotic evolution; however, its progression is still somewhat debated. According to the nucleus-first hypothesis, the ancestral prokaryote first evolved a membrane to enclose DNA and form the nucleus. Conversely, the mitochondria-first hypothesis suggests that the nucleus was formed after endosymbiosis of mitochondria.
Contrary to the endosymbiont theory, the eukaryote-first hypothesis proposes that the simpler prokaryotic and...
Contrary to the endosymbiont theory, the eukaryote-first hypothesis proposes that the simpler prokaryotic and...
40.3K
02:31Synteny and Evolution
3.8K
John H. Renwick first coined the term “synteny” in 1971, which refers to the genes present on the same chromosomes, even if they are not genetically linked. The species with common ancestry tend to show conserved syntenic regions. Therefore, the concept of synteny is nowadays used to describe the evolutionary relationship between species.
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral...
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral...
3.8K
02:05Gene Evolution - Fast or Slow?
3.4K
3.4K
02:05Gene Evolution - Fast or Slow?
8.0K
The genomes of eukaryotes are punctuated by long stretches of sequence which do not code for proteins or RNAs. Although some of these regions do contain crucial regulatory sequences, the vast majority of this DNA serves no known function. Typically, these regions of the genome are the ones in which the fastest change, in evolutionary terms, is observed, because there is typically little to no selection pressure acting on these regions to preserve their sequences.
In contrast, regions which code...
In contrast, regions which code...
8.0K