Symptomatic Chiari Malformation
Symptomatic Chiari Malformation
Persons with Myelomeningocele have abnormalities that are not limited to their spinal cord. These include the development of hydrocephalus (in up to 85% of patients) and the development of symptoms related to the area where the brain and spine join (Chiari malformation).
What is a Chiari malformation?
What type occurs in SB?
When brain tissue is below the level of the fourth cervical vertebrae (C4), the likelihood of serious symptoms occurring from this abnormality is high. Conversely, minor degrees of descent of the brain well above the level of C3, are less likely to have clearly recognized progressive symptoms. Symptoms tend to come from one of three areas of the central nervous system: cerebellum, lower brain stem and spinal cord. The symptom complex is quite different with each of these and appears to be predictable to some degree, based on the patient's age when symptoms are first noticed.
What are the symptoms?
A child or adolescent may develop stiffness or spasticity of the arms or hands. This stiffness may be so severe that the upper extremities will not work smoothly. If these symptoms are progressive, they may make the upper extremities useless to the patient. Associated with the stiffness may be loss of feeling or sensation in the hands or arms. This loss may not be to all types of sensation, but may be restricted to certain types, such as the loss of pain or loss of temperature sensation.
The third area that can be affected is the cerebellum. This portion of the brain, located in the back of the head, controls balance and coordination. These symptoms are the least likely to occur and may be the most difficult to pinpoint- especially in the younger child.
What tests are done for Arnold Chiari malformation?
Additional examinations, which test the integrity of the functional aspects of the brain stem and spine, are sometimes helpful. These include a CO 2 breathing test that reflects the function of the brain's breathing center, somatosensory evoked response (timing of electrical signals that connect the arms and legs with the brain), brain stem evoked response (ability of the brain to process sounds) and others.
What is the “shunt first” approach to care?
What about surgery?
The operation is relatively safe in experienced hands but should be performed by a surgeon especially trained and experienced in operations on children's brain malformations. The technical excellence necessary to perform this operation is high and there is no substitute for significant experience.
The alternative strategy of further conservative care for patients with symptomatic Chiari malformation demands special comment. It is currently believed that the majority of Spina Bifida patients do not demonstrate rapid clinical progression. Opinions vary as to whether an individual patient should have surgery or simply be clinically monitored. Generally, the more the patient's progression is felt to be secondary to their Chiari malformation, the more universal is the acceptance of operative intervention. Serial examinations of the individual are essential in the evaluation of this problem and again, fix the shunt first!
This information does not constitute medical advice for any individual. As specific cases may vary from the general information presented here, SBA advises readers to consult a qualified medical or other professional on an individual basis.