Chiari 1.5 Malformation : An Advanced Form of Chiari I Malformation.
- Author:
In Kyeong KIM
1
;
Kyu Chang WANG
;
In One KIM
;
Byung Kyu CHO
Author Information
1. Division of Pediatric Neurosurgery, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea. bkcho@snu.ac.kr
- Publication Type:Case Report
- Keywords:
Chiari 1.5 malformation;
Asymptomatic hydrocephalus;
Syringomyelia
- MeSH:
Adolescent;
Brain Stem;
Encephalocele;
Follow-Up Studies;
Foramen Magnum;
Humans;
Hydrocephalus;
Medulla Oblongata;
Neck Pain;
Neuroimaging;
Syringomyelia
- From:Journal of Korean Neurosurgical Society
2010;48(4):375-379
- CountryRepublic of Korea
- Language:English
-
Abstract:
The Chiari 1.5 malformation is defined as a tonsillar herniation within a Chiari I malformation with additional caudal descent of the brainstem through the foramen magnum. We describe a patient with Chiari I malformation who evolved to Chiari 1.5 malformation during longitudinal follow-up. A 15-year-old girl presented with neck pain during exercise for two years. She had been diagnosed with Chiari I malformation with mild hydrocephalus after minor cervical trauma at the age of six years. At that time, she was asymptomatic. After she complained of aggravated neck pain, neuroimaging (nine years after first imaging) revealed caudal descent of the brainstem and syringomyelia in addition to progression of tonsillar herniation. Posterior fossa decompressive surgery resulted in complete resolution of neck pain. Based on neuroimaging and operative findings, she was diagnosed as Chiari 1.5 malformation. Neuroimaging performed seven months after surgery showed an increased anterior-posterior diameter of the medulla oblongata and markedly decreased syringomyelia. This case demonstrates progressive developmental process of the Chiari 1.5 malformation as an advanced form of the Chiari I malformation.