Flexion-extension cervical MRI imaging in pediatric patients with achondroplasia unsupervised by neurosurgery or radiology, is it safe?

Background and purpose: Achondroplasia, a common form of skeletal dysplasia, can be associated with cervical spine compression and cerebrospinal fluid (CSF) flow compromise, potentially leading to neurological complications. Accurate assessment of the cervical spine is essential for identifying children at increased risk of neurological injury. However, concerns regarding the safety of dynamic MRI under anesthesia in young children have limited its use. This study evaluates the safety of dynamic MRI under anesthesia in pediatric patients with achondroplasia, utilizing the largest dataset reported to date.

Materials and methods: In this retrospective study, we reviewed the medical records of 81 patients with achondroplasia who underwent a total of 124 flexion-extension MRIs under anesthesia. All imaging procedures were performed by MR technologists and anesthesiologists without direct supervision by a neurosurgeon or radiologist. Data reviewed included anesthesia type, neurological examinations by a senior pediatric neurosurgeon before and after imaging, surgical intervention, follow-up MRIs, and the presence of CSF obstruction at the craniocervical junction.

Results: A total of 81 patient charts were reviewed (mean age, 2.03 ± 2 years; age range, 1 month to 6 years). Of the 124 flexion-extension MRIs, 113 were performed under general anesthesia, and 11 under sedation alone. Foramen magnum stenosis with CSF flow compromise was documented in 38 cases (46%). No adverse events, neurological deficits, or anesthesia-related complications were documented. Neurological examinations conducted by the senior author, a pediatric neurosurgeon, before and after imaging remained stable across all cases.

Conclusion: Flexion-extension MRI did not result in adverse outcomes in this cohort of pediatric patients with achondroplasia. While these findings support the dynamic MRI's safety in appropriate settings, further studies are needed to validate these results and explore its broader application.