Acquired Chiari Malformation and Syringomyelia Secondary to Space-Occupying Lesions: A Systematic Review

Resolution of Tonsillar Herniation and Syringomyelia Following Resection of a Large Anterior Frontal Parasagittal Meningioma

“…In these patients, the SOL may be resected, resolving the ACM and syringomyelia without the need for posterior fossa decompression. In the majority of reported cases, SOLs are located in the posterior fossa or parieto-occipital region [3]. Here, we present an unusual case of ACM and syringomyelia that completely resolved following the resection of a large frontal parasagittal meningioma.…”

“…This is likely due to the resulting craniospinal pressure gradient, which is directed toward the lower intraspinal pressure, causing caudal herniation of the cerebellar tonsils [4,6]. In addition, syringomyelia formation may be driven by functional obstruction at the foramen magnum, leading to increased intracranial and cervical CSF pulse pressure relative to the subarachnoid space [3,7]. However, the exact mechanism of syringomyelia formation remains unclear, as several pathogenic processes have been proposed, ranging from altered CSF flow dynamics to reduced cervical venous compliance, leading to the accumulation of extracellular fluid in the cervical spinal cord [8].…”

“…However, the exact mechanism of syringomyelia formation remains unclear, as several pathogenic processes have been proposed, ranging from altered CSF flow dynamics to reduced cervical venous compliance, leading to the accumulation of extracellular fluid in the cervical spinal cord [8]. [3]. Specifically, the authors examined the differences in clinical outcomes for patients who underwent SOL resection with or without posterior fossa decompression.…”

Chiari I Malformation and Basilar Invagination in Fibrous Dysplasia: Prevalence, Mechanisms, and Clinical Implications

“…Intracranial hypertension, another form of craniocerebral disproportion, may also cause CM1 in FD. Intracranial hypertension describes the mechanism of tonsillar displacement resulting from ectopic intracranial masses that increase pressure within a normal cranial vault . Two cases of CM1 have been reported in the setting of intracranial hypertension secondary to rapidly enlarging aneurysmal bone cysts in FD .…”

“…Intracranial hypertension describes the mechanism of tonsillar displacement resulting from ectopic intracranial masses that increase pressure within a normal cranial vault. (34) Two cases of CM1 have been reported in the setting of intracranial hypertension secondary to rapidly enlarging aneurysmal bone cysts in FD. (7,10) Similarly, several subjects in this study with CM1 had evidence of aneurysmal bone cysts and arachnoid cysts on radiographic evaluation.…”