The pathogenesis of Chiari malformation Type I (CM-I) and associated syringomyelia is incompletely understood. Patients often present in middle age with incidental or minimally symptomatic CM-I, whose management is controversial. One option is clinical and radiographic observation of asymptomatic and minimally symptomatic patients. The authors here present the case of a 36-year-old woman who had been monitored for 6 years for a minimally symptomatic CM-I and cervicothoracic syrinx. After 5 years of follow-up, she suffered spontaneous rupture of a cerebral cavernous malformation when she was 27 weeks pregnant. The ruptured cavernous malformation and hematoma were operatively managed via a right frontal craniotomy. Ten months after the craniotomy for resection of the ruptured cavernous malformation, follow-up MRI demonstrated resolution of the CM-I and syrinx. Few similar cases have been reported in adults. This case argues for the presence of dynamic factors in the development and maintenance of CM-I and supports the nonoperative treatment of asymptomatic and minimally symptomatic patients.
Abbreviations used in this paper:CM-I = Chiari malformation Type I; CTA = CT angiography; MRA = MR angiography.
Address correspondence to: Carl B. Heilman, M.D., Department of Neurosurgery, Tufts Medical Center and Tufts University School of Medicine, 800 Washington Street, #178, Boston, Massachusetts 20111. email: firstname.lastname@example.org.
Please include this information when citing this paper: published online February 10, 2012; DOI: 10.3171/2012.1.JNS11580.
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