Back to Search
Start Over
Operative findings and surgical outcomes in patients undergoing Chiari 1 malformation decompression: relationship to the extent of tonsillar ectopia
- Source :
- Acta Neurochirurgica. 162:1539-1547
- Publication Year :
- 2019
- Publisher :
- Springer Science and Business Media LLC, 2019.
-
Abstract
- The diagnosis of Chiari 1 malformation is based on the extent of tonsillar ectopia.To examine the relationship between the extent of tonsillar ectopia and the intra-operative findings and clinical outcome following Chiari decompression surgery.Patients were divided into four groups depending on the position of the cerebellar tonsil (T): group 1: 0 T 3; group 2: 3 ≤ T ≤ 5; group 3: 5 T ≤ 10; and group 4: T 10. Intra-operative observations were recorded with regard to compression of the brain stem by posterior inferior cerebellar artery (pica), neuroma formation along the first cervical (C1), and accessory spinal nerves (XI), and pallor of the cerebellar tonsils. Brain stem auditory evoked potentials, (BAEP), were monitored in each case. One hundred sixty-eight patients accrued between 2009 and 2013 agreed to participate in an outcome study to determine the effectiveness of foramen magnum decompression. Findings across the four groups were compared using one-way ANOVA. Observed differences were further subjected to paired analysis. Intra-group comparisons were made using the paired t test. A P value less than 0.05 was considered statistically significant.There were 98 patients in group 1, 147 patients in group 2, 180 patients in group 3, and 63 patients in group 4. The mean extent of tonsillar ectopia was 0.4, 4.0, 7.1, and 14.3 mm in the four groups respectively. The prevalence of tonsillar pallor was greatest in group 4. Otherwise, there was no difference observed in the operative findings. A reduction of 0.1 msec in the wave III-wave V latency of the BAEP was noted in all four groups with equal frequency. One hundred ten patients complied with at least 6 months follow-up. There was no difference in the prevalence of symptoms between the four groups at the time of initial evaluation and at 6 weeks and 6 months following surgery. There was a statistically significant reduction in the intensity of individual symptoms 6 months following surgery regardless of the extent of tonsil ectopia.Other than the finding of tonsillar pallor, there was no relationship between the extent of tonsillar ectopia and the intraoperative anatomical and physiological observations, nor was there any relationship to the likelihood of symptomatic improvement following surgery. These observations call into question the focus on the extent of tonsillar of ectopia in assessing the patient who presents with symptoms of the Chiari malformation.
- Subjects :
- Adult
Male
medicine.medical_specialty
Adolescent
Intraoperative Neurophysiological Monitoring
Decompression
Palatine Tonsil
Choristoma
Pallor
030218 nuclear medicine & medical imaging
03 medical and health sciences
Postoperative Complications
0302 clinical medicine
medicine.artery
Evoked Potentials, Auditory, Brain Stem
medicine
Humans
Foramen Magnum
Chiari malformation
Foramen magnum
business.industry
Middle Aged
Decompression, Surgical
medicine.disease
Neuroma
Arnold-Chiari Malformation
Surgery
Posterior inferior cerebellar artery
medicine.anatomical_structure
Tonsil
Cerebellar tonsil
Female
Neurology (clinical)
medicine.symptom
business
030217 neurology & neurosurgery
Brain Stem
Subjects
Details
- ISSN :
- 09420940 and 00016268
- Volume :
- 162
- Database :
- OpenAIRE
- Journal :
- Acta Neurochirurgica
- Accession number :
- edsair.doi.dedup.....02cb4edc5eaea58e81ae54dec91f1d7c