Utilization of Vestibular Information for Balance Control in Children with Chiari I Malformation

(1) Background: Surgery for Chiari I malformation (CMI) is indicated when typical clinic-radiological features (syringomyelia, exertional headaches, sleep apnea syndrome, and tetraparesis) are present. Sometimes, patients have atypical complaints suggestive of otolaryngological (ENT) involvement, and it is sometimes difficult for the neurosurgeon to determine if these complaints are related to the CMI. Our aim was to describe postural control patterns in children with CMI using computerized dynamic posturography. To our knowledge, this is the first study addressing postural instability in pediatric CMI patients. (2) Methods: Twenty-eight children aged 6 to 17 years with both radiologically confirmed CMI and clinical ENT complaints were included. The children were separated into two groups, operated and non-operated patients, based on neurosurgical indication. Epidemiologic and posturographic results (CDP-Equitest^®) were compared between both groups, as well as pre- and postoperatively in Group 2. (3) Results: In Group 2 patients, significant improvement of global SOT was found after intervention. When the three sensorial aspects of postural control calculated by the system were independently assessed, the greatest improvement was in the vestibular ratio. We also observed an altered CoG pattern ("lateral deviation") in the Group 2 patients, which significantly differed from those in Group 1. Lateral deviation was significantly reduced postoperatively in the Group 2 patients. A correspondence between preoperative MRI and the side of lateralization on posturography was found in four children, but this cannot be regarded as significant due to the low number of patients. (4) Conclusions: Postural control seems to improve after surgery for CMI in children, mostly due to the improvement in vestibular function. There is a correspondence between the side of lateral deviation and the side of greatest tonsillar descent on MRI and perioperatively. Further studies are needed to support these results and to confirm the utility of CDP in CMI patients.