Assessment of Cerebrospinal Fluid Flow in Patients with Foramen Magnum Meningiomas

• Published in: Journal of Neurological Surgery Part B: Skull Base Vol. 77; no. S 02
• Main Authors: Kondrahov, Sergey, Tanyashin, Sergey V., Shimansky, Vadim, Zaharova, N. E., Fadeeva, L. M., Karnaukhov, Vasiliy V., Poshataev, Vladimir, Odamanov, Djemil A., Shevchenko, Kirill
• Format: Conference Proceeding Journal Article
• Language: English
• Published: 09.09.2016
• ISSN: 2193-6331; 2193-634X
• DOI: 10.1055/s-0036-1592658

Introduction: Foramen magnum meningiomas represent only 0.3 to 3.2% of all diagnosed meningiomas. In the world literature, data describing the state of cerebrospinal fluid (CSF) flow in these patients are scarce. Objective: Our aim was to evaluate the degree of recovery CSF flow depending on the extent of surgical intervention. Materials and Methods: The study was performed in 19 patients (16 females, 3 males) with foramen magnum meningiomas before and after the operation. CSF flow was assessed by phase-contrast MRI and dopplerography examination of venous blood flow in the straight sinus. Removing the tumor was performed in most cases via a midline suboccipital approach (17 patients), two cases was performed advanced transclival approach. Total resection was performed in 6 (31.58%) patients, subtotal resection - 6 (31.58%), the partial removal and duraplasty - 7 (36.84%). Results: Before surgery, according to the phase-contrast MRI, an increase of linear and volumetric speeds of CSF flow by 1.5 to 4 times compared with the normal values is noted of 17 patients, 2 patients had normal values. According to the ultrasonography, increase of brain tissue elasticity and difficulty of venous outflow from the cranial cavity were found in all 19 patients. After surgery: According to phase-contrast MRI, normalization of linear and volumetric speeds CSF flow was found in 4 patients after total removal, in 4 patients after subtotal removal, in one case after partial removal. Linear and volumetric speeds CSF flows were not changed in 2 patients after total removal, in 3 patients after subtotal removal, in 4 patients after partial removal. Increasing linear and volumetric speeds CSF flow detected in one case after subtotal removal and in 2 patients after partial removal. According to the ultrasonography, reduction in brain tissue elasticity and normalization of venous blood flow velocity to normal were found in 16 patients. In one case, activities are ascertained, indicating the block of CSF flow at craniovertebral junction. In two patients, positive dynamics was found during the decrease of brain tissue elasticity and venous blood flow velocity. Conclusion: According to complex phase-contrast MRI and ultrasonography, there is no significant correlation between the degree of meningioma resection and CSF flow normalization.