Basilar invagination is a medical condition where the base of the skull, specifically the occipital bone, pushes upward into the spinal canal. This can lead to compression of the brainstem and cervical spinal cord, potentially causing neurological symptoms such as headaches, neck pain, and balance issues. This condition is often associated with Chiari malformation, a structural defect in the brain. Diagnosis typically involves imaging studies like MRI or CT scans. Treatment may include monitoring symptoms or surgical intervention to relieve pressure on the nervous system.