Posterior odontoid process angulation in pediatric Chiari I malformation: an MRI morphometric external validation study
| العنوان: | Posterior odontoid process angulation in pediatric Chiari I malformation: an MRI morphometric external validation study |
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| المؤلفون: | Noel Tulipan, Matthew A. Day, Luke Tomycz, Chevis N. Shannon, Travis R. Ladner, Michael C. Dewan, John C. Wellons |
| المصدر: | Journal of Neurosurgery: Pediatrics. 16:138-145 |
| بيانات النشر: | Journal of Neurosurgery Publishing Group (JNSPG), 2015. |
| سنة النشر: | 2015 |
| مصطلحات موضوعية: | Male, Cephalometry, Decompression, Population, Chiari I malformation, Odontoid Process, Humans, Medicine, Body Weights and Measures, Child, education, Retrospective Studies, Odontoid process, Foramen magnum, education.field_of_study, business.industry, External validation, General Medicine, Anatomy, Decompression, Surgical, medicine.disease, Magnetic Resonance Imaging, Arnold-Chiari Malformation, Exact test, medicine.anatomical_structure, Child, Preschool, Female, Dura Mater, business, Syringomyelia |
| الوصف: | OBJECT Osseous anomalies of the craniocervical junction are hypothesized to precipitate the hindbrain herniation observed in Chiari I malformation (CM-I). Previous work by Tubbs et al. showed that posterior angulation of the odontoid process is more prevalent in children with CM-I than in healthy controls. The present study is an external validation of that report. The goals of our study were 3-fold: 1) to externally validate the results of Tubbs et al. in a different patient population; 2) to compare how morphometric parameters vary with age, sex, and symptomatology; and 3) to develop a correlative model for tonsillar ectopia in CM-I based on these measurements. METHODS The authors performed a retrospective review of 119 patients who underwent posterior fossa decompression with duraplasty at the Monroe Carell Jr. Children’s Hospital at Vanderbilt University; 78 of these patients had imaging available for review. Demographic and clinical variables were collected. A neuroradiologist retrospectively evaluated preoperative MRI examinations in these 78 patients and recorded the following measurements: McRae line length; obex displacement length; odontoid process parameters (height, angle of retroflexion, and angle of retroversion); perpendicular distance to the basion-C2 line (pB–C2 line); length of cerebellar tonsillar ectopia; caudal extent of the cerebellar tonsils; and presence, location, and size of syringomyelia. Odontoid retroflexion grade was classified as Grade 0, > 90°; Grade I,85°–89°; Grade II, 80°–84°; and Grade III, < 80°. Age groups were defined as 0–6 years, 7–12 years, and 13–17 years at the time of surgery. Univariate and multivariate linear regression analyses, Kruskal-Wallis 1-way ANOVA, and Fisher’s exact test were performed to assess the relationship between age, sex, and symptomatology with these craniometric variables. RESULTS The prevalence of posterior odontoid angulation was 81%, which is almost identical to that in the previous report (84%). With increasing age, the odontoid height (p < 0.001) and pB–C2 length (p < 0.001) increased, while the odontoid process became more posteriorly inclined (p = 0.010). The pB–C2 line was significantly longer in girls (p = 0.006). These measurements did not significantly correlate with symptomatology. Length of tonsillar ectopia in pediatric CM-I correlated with an enlarged foramen magnum (p = 0.023), increasing obex displacement (p = 0.020), and increasing odontoid retroflexion (p < 0.001). CONCLUSIONS Anomalous bony development of the craniocervical junction is a consistent feature of CM-I in children. The authors found that the population at their center was characterized by posterior angulation of the odontoid process in 81% of cases, similar to findings by Tubbs et al. (84%). The odontoid process appeared to lengthen and become more posteriorly inclined with age. Increased tonsillar ectopia was associated with more posterior odontoid angulation, a widened foramen magnum, and an inferiorly displaced obex. |
| تدمد: | 1933-0715 1933-0707 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::06a1bfcd81ed35022966050bd21dfe60Test https://doi.org/10.3171/2015.1.peds14475Test |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....06a1bfcd81ed35022966050bd21dfe60 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 19330715 19330707 |
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