Although many people may have subtle Chiari malformations that are evident on MRI, few malformations are serious enough to warrant treatment. To spare patients unnecessary surgery that will not alleviate their symptoms, neurologists and neurosurgeons at Mayo Clinic take a conservative approach to treating Chiari malformation.
Mayo specialists usually recommend surgery as the most appropriate treatment to relieve the pressure on the brain stem, cerebellum and spinal cord, and to re-establish spinal fluid circulation. The goal of treatment is to halt or reverse the progression of signs and symptoms.
At Mayo, the surgery usually recommended for patients with treatable symptoms of Chiari malformation generally takes two to three hours. Recovery time in the hospital could take from two to four days.
In the surgical procedures, posterior fossa craniectomy (removal of a portion of the skull) or posterior fossa decompression (the release of pressure), a small section of bone at the back of the head is removed to make more room for the cerebellum and relieve pressure.
During surgery, the dura (covering of the brain) may also be enlarged with a patch created from synthetic material or tissue from the patient's leg muscle. The enlargement creates more room for the brain and the spinal cord and helps to establish the flow of cerebral spinal fluid.
A cervical laminectomy is performed to remove the bone forming the back of the vertebra or lamina. Both the posterior fossa decompression and the cervical laminectomy are done at the same time and through the same surgical incision in the back of the head and upper neck.
The surgery may be modified if there is a syrinx (fluid-filled cavity in the spinal cord) present or if the patient has hydrocephalus (excess fluid buildup within the brain).
Surgery performed on patients who Mayo specialists have determined can truly benefit from the operation often successfully relieves the symptoms of Chiari malformation. More than 90 percent of patients who have the surgery do quite well and their symptoms improve.