Innovative Treatment for Pre- Operative Occipital Nerve Pain Associated with Chiari 0 Malformation

Abstract

Chiari 0 malformation is a disorder within the spectrum of Arnold- Chiari malformations characterized by cerebellar changes present during fetal development and early childhood. Specifically, Chiari 0 is classified by characteristics that include either lack of protrusion of the cerebellar tonsils into the foramen magnum or protrusion less than 5 millimeters, which is the current minimum cutoff for Chiari I classification. Due to the subtle changes in the cerebellar region regarding Chiari 0, patients with this malformation often present with neck and occipital pain along with occipital headaches. It is suggested that this may be due to abnormal blockage of cerebrospinal fluid (CSF) that causes entrapment and impingement of the occipital nerve. In the cases of two teenage patients, both were referred to Pediatric Neurosurgery in Lubbock, Texas for complaints of chronic headaches and neck pain. After previous pain remedies proved to be unsuccessful in providing lasting relief, the patients were deemed candidates to receive an innovative treatment option to manage their chronic headaches and neck pain. The patients were referred to receive epidural lysis of adhesions (LOA) which would provide the lasting relief that the patients were seeking. LOA is a procedure that includes using a needle, Racz catheter, and injectable contrast guided with fluoroscopy to locate the entrapment of the occipital nerve. LOA utilizes the injection of hyaluronidase dissolved in normal saline to free the entrapped nerve so that a local anesthetic/steroid solution can be injected to provide pain relief. Lysis of adhesions should be considered as a minimally invasive treatment for Chiari 0 malformations, whose primary symptoms are intractable occipital headaches.