BACKGROUND: In @entity1645 (CMI), the obstruction of cerebrospinal fluid (CSF) flow through the foramen magnum is believed to cause alterations of @entity428 ( @entity428 ) pulsations. @entity5663 ( @entity5663 ) is therefore considered a treatment of choice. However, the pathophysiology of CMI is poorly understood and it remains unknown how @entity428 alterations relate to symptoms and radiological findings. This study was undertaken to measure pulsatile pressure and its gradient between intracranial and lumbar compartments, and to determine its relationship to clinical and radiological findings. METHOD: In @entity1 with symptomatic CMI, we simultaneously measured @entity428 and lumbar CSF pressure, with particular focus on analysis of pulsatile pressure. Ventricular CSF volume (VV), intracranial volume (ICV) and posterior cranial fossa volume (PCFV) were calculated using volumetry software. RESULTS: In 26 @entity1 (median 35  years), we found clearly abnormal or borderline values of @entity428 in 18/26 @entity1 (69  %; median 4.5  mmHg) and abnormal pulsatile pressure gradient in 17/24 @entity1 (71  %; median 2.6  mmHg). The correlation between @entity428 and the pulsatile pressure gradient was significantly positive (p   <   0.001). We found no significant correlation between pulsatile or static pressure and extent of tonsillar ectopy, VV, ICV or PCFV. The pulsatile pressure gradient was significantly higher in @entity1 with @entity1644 (p   =   0.02). CONCLUSIONS: In this cohort, the @entity428 was elevated in 69  %. The intracranial-lumbar pulsatile pressure gradient was abnormal in 71  % and significantly higher in @entity1 with @entity1644 . The elevated @entity428 significantly correlated with pulsatile pressure gradient; no similar correlation was found for static @entity428 . We interpret the results as providing evidence of impaired intracranial compliance as an important pathophysiological mechanism in CMI.

Comparison of pulsatile and static pressures within the intracranial and lumbar compartments in XXXX with @entity1645 : a prospective observational study.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity1644 :: ('MESH:D013595', 'Disease') :: ['syringomyelia'] @entity428 :: ('MESH:D019586', 'Disease') :: ['ICP', 'intracranial pressure', 'pulsatile ICP'] @entity1645 :: ('MESH:D001139', 'Disease') :: ['Chiari malformation type 1'] @entity5663 :: ('MESH:D003665', 'Disease') :: ['FMD', 'Foramen magnum decompression']
@entity1 :: (9606,Species) :: ['patients']
