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Symptomatic Chiari Malformation People with SB frequently have an Arnold Chiari Malformation

Persons with Myelomeningocele have abnormalities that symptoms occurring from this abnormality is high. are not limited to their . These include the Conversely, minor degrees of descent of the brain development of (in up to 85% of patients) well above the level of C3, are less likely to have clearly and the development of symptoms related to the area recognized progressive symptoms. Symptoms tend to where the brain and spine join (Chiari malformation). come from one of three areas of the central : , lower brain stem, and spinal cord. The symptom complex is quite diferent with each of these What is a Chiari malformation? and appears to be predictable to some degree, based on Over a hundred years ago, Professor Chiari, an Austrian pathologist studied a group of patients who had a portion of the brain displaced into the . He graded these malformations in order of severity. Type I (the What are the symptoms? mildest form) occurs when the lowest part of the Newborns and young infants with symptoms tend to cerebellum, called the cerebellar tonsils, descends a short distance into the cervical spine. • poor feeding

What type occurs in SB? • weak or poor cry Chiari Type II or Arnold-Chiari malformation, is a more • inspiratory (noisee severe form in which the and some on breathing in), portion of the brain stem descend into the cervical frequently exacerbated spine. Many changes of the brain are associated by crying, arching of the with this abnormality. Although some degree of this head, and possibly facial malformation is present in the vast majority of persons weakness, among others.s. When severe, the about one of three individuals. This 33% may be a symptoms may result

longer periods of time, adolescents and young adults to maintain life. The appear to have some propensity to develop clinical symptomatic Chiari progression. The development of symptoms related malformation is currently to the Chiari malformation is, in part, related to the the leading cause of severity of the malformation.

When brain tissue is below the level of the fourth population, particularly in (C4), the likelihood of serious early life.

• 1600 Wilson Blvd. Suite 800 Arlington, VA 22209 • 800- 621 -3141 A child or adolescent may develop stiffness or What is the “ rst” approach to care? of the arms or hands. This stiffness may be so severe Of primary importance in patients suspected of being that the upper extremities will not work smoothly. If symptomatic from their Chiari malformation is to ensure these symptoms are progressive, they may make the normal prior to any consideration of upper extremities useless to the patient. Associated intervention for the Chiari malformation. This means that with the stiffness may be loss of feeling or sensation in the patient should have her/his shunt evaluated The the hands or arms. This loss may not be to all types of “shunt #st” approach cannot be over emphasized. (See sensation, but may be restricted to certain types, such SBA’s Hydrocephalus information sheet.) If there is any as the loss of pain or loss of temperature sensation. question concerning shunt function, the system should The third area that can be affected is the cerebellum. be surgically inspected. Once it is determined that the This portion of the brain, located in the back of the intracranial pressure is normal, and that the shunt is head, controls balance and coordination. These working properly, the next question to be answered is symptoms are the least likely to occur and may be whether the patient’s symptoms are life threatening and/ the most to pinpoint- especially in the or progressive. Most patients with radiographic evidence younger child. of a Type II Chiari malformation do not need surgery and appear not to be progressive. If serious symptoms are present, consideration is given to surgical intervention. What tests are done for Arnold Chiari malformation? What about surgery? There is variability in how medical centers perform testing of function. With the advent of The purpose of the operation is to unroof the cervical magnetic resonance imaging (MRI), the evaluation spine over the abnormally low brain and to reestablish of structural abnormalities of the cervical spine has normal movement of the CSF. become greatly simplied. Although other methods The operation is relatively safe in experienced hands are available, MRI provides extremely high-resolution but should be performed by a surgeon especially images of the area of concern with little to no risk to trained and experienced in operations on children’s the patient. Not only can the position of the brain be brain malformations. The technical excellence obtained, but even or other problems within the necessary to perform this operation is high and there is spinal cord can be assessed. The MRI scan can also be no substitute for signicant experience. used to evaluate the ow of cerebrospinal uid (CSF) around the back part of the brain. The alternative strategy of further conservative care for patients with symptomatic Chiari malformation Additional examinations, which test the integrity of demands special comment. It is currently believed the functional aspects of the brain stem and spine, are that the majority of Spina Bida patients do not sometimes helpful. These include a CO 2 breathing test demonstrate rapid clinical progression. Opinions that re ects the function of the brain’s breathing center, vary as to whether an individual patient should have somatosensory evoked response (timing of electrical surgery or simply be clinically monitored. Generally, the signals that connect the arms and legs with the brain), more the patient’s progression is felt to be secondary brain stem evoked response (ability of the brain to to their Chiari malformation, the more universal process sounds) and others. is the acceptance of operative intervention. Serial examinations of the individual are essential in the evaluation of this problem and again, x the shunt rst!

This information does not constitute medical advice for any individual. As specic cases may vary from the general information presented here, SBA advises readers to consult a qualied medical or other professional on an individual basis.

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