Management of Chiari Malformation and Fibromyalgia

In order to appropriately care for patients with the Chiari I malformation and/or syringomyelia, one must first define the presence of tonsillar herniation, its extent, and its physiological and clinical significance. The history and physical examination are extraordinarily important in this regard. These often lead to imaging studies, such as MRI. The identification of a Chiari malformation on MRI is usually an indicator for further diagnostic work-up. This usually entails a CT or MRI of the head to demonstrate the presence or absence of hydrocephalus and other associated anomalies. MRI of the cervical and thoracic spine are also appropriate in order to rule in or out the presence of syringomyelia. If a syrinx is present, a contrast enhanced MRI (MRI following the injection of a contrast and enhancing agent; i.e., gadolinium) may be indicated in some circumstances. Finally, many surgeons feel that a cine MRI of the cervicomedullary junction is appropriate to determine if an obstruction of CSF flow occurs in this region (i.e., a physiologically significant Chiari malformation).

Patients who have significant symptoms and who have a physiological explanation for these symptoms (see above) may have a clinically significant Chiari malformation. This constellation of findings, along with the appropriate history, physical examination and neurologic examination, in fact, define the optimal surgical candidate. Aside from surgery, further treatment is usually indicated. This often includes pain management and rehabilitation. Most importantly, it also includes the establishment of a working diagnosis and treatment plan by a multidisciplinary team, including neurosurgeons, neurologists and rheumatologists.

All patients with a Chiari malformation who are referred to the neurosurgery department at he Cleveland Clinic Foundation undergo a careful history and thorough neurological examination. "Hard" neurological findings such as nystagmus, external ophthalmoplegia, absent "gag" reflex, reproducible sensory abnormalities, lower extremity brisk reflexes and upper extremity hyporeflexia, quantifiable weakness, muscle atrophy, fasciculations, and Babinski and Hoffmann signs are noted. An MRI of the brain and spinal cord is performed, along with flow studies (CINE MRI) to delineate the extent of physiologic and anatomical abnormalities. The patients are then referred to a rheumatologist with specific knowledge and expertise regarding the Chiari malformation and syringomyelia, who is blinded to the previous neurosurgical examination and testing (to prevent bias). A careful history, with emphasis on psychosocial factors and current levels of stress is obtained. The cardinal symptoms of chronic fatigue syndrome (CFS) and fibromyalgia (FMS) are sought, and an extensive sleep history is obtained. A neurological examination is performed, MRI findings reviewed, and previous findings confirmed. New findings are noted. A screening FMS Questionnaire and Beck Depression Inventory (BDI) are completed. Tender points are quantitated. With this information, the rheumatologist makes an independent assessment of the patient's complaints.

After the aforementioned evaluation, it is generally possible to assign patients into one of three different categories:

1. Patients who have clinical features of a Chiari malformation as evidenced by neurological findings consistent with disruption of central pathways involving the cerebrospinal, cerebellospinal or sensory spinothalamic pathways. Corroborative findings include cerebellar tonsillar herniation, syringomyelia, and obstruction to cerebrospinal fluid at these levels. These patients are the best candidates for corrective surgery.

2. Patients who have features of FMS and CFS. These patients have sleep disturbances, psychosocial stressors, multiple active tender points, and elevated FMS questionnaire score and BDI score. No neurologic findings are demonstrated, although many subjective symptoms are present. They may or may not have a Chiari malformation/syringomyelia (herniation > 8mm), which, when present, is usually mild in degree. Moreover, there is no obstruction to spinal fluid flow. These patients will not benefit from surgery.

3. A "mixed" pattern, where (1) and (2) coexist. These patients represent a unique challenge, since there may be features of FMS present in the setting of an anatomic and phsyiologic Chiari malformation. While a minority of these patients may actually benefit from surgery, our approach is conservative for most. Frequently, we will obtain a neurology consult, and objectively confirm the symptoms and physical findings by electrophysiological studies, and evoked potentials. These patients are closely followed, and progression of their neurological findings will trigger a repeat evaluation. Most important, these patients are educated about the nature of FMS, and associated disrupted sleep and dysthymia, and are aggressively treated with appropriate medications and a graded aerobic exercise program.

The "gold" standard of evaluation is an appropriate history and physical exam which is confirmed by neuroradiological testing. This standard often requires a multidisciplinary approach with collaboration among interested neurosurgeons, rheumatologists, and neurologists. Perhaps most important in the aforementioned diagnostic and treatment scheme is the management of those patients who fall into the third group. These patients are felt to have symptoms associated with the Chiari malformation, but do not have clear-cut indications for surgery. Their symptoms are aggressively managed and through a process of continued re-evaluation by the multidisciplinary team the most appropriate therapy is sought on a case by case basis.