Speakers

Hydrostatic feature of CSF physiology
1108 13:00-13:10
Cerebrovascular/304B
CSF circulation-new and old concept The classic hypothesis describes CSF as a unidirectional flow (circulation) from brain ventricles through the CSF system to the cortical subarachnoid space, where it is passively absorbed into venous sinuses mainly by arachnoid granulations. Models of cerebrospinal fluid (CSF) circulation have been mainly proposed in the last century. Conclusions of past experiments are often not justified due to lack of reproducibility and methodological issues. Challenging to old concept are novel insights utilizing molecular and cellular biology as well as neuroimaging, which indicate that CSF physiology may be much more complex than previously believed. It is clear today that choroidal plexuses are not biological pumps that provides unidirectional bulk CSF flow. The “CSF circulation comprises” not only a directed flow of CSF but in addition a pulsatile to and fro movement throughout the entire brain with local fluid exchange between blood, interstitial fluid and CSF. Osmolarity of the intracranial and intraspinal liquids and the hydrostatic pressure inside the CSF system are the main driving forces for CSF movement along the CSF system. Modern neuroimaging is able to demonstrate the CSF movement in real time. Neuroimaging, so as many animal experiments, are suggesting that CSF circulation is not existing in a way it was introduced a 100 years ago.

Surgery vs embolization in the treatment of spinal dural AV fistulas
1109 15:40-15:50
AASNS & WANS Joint Seminar/305
ABSTRACT Background Spinal dural arteriovenous fistulas (sDAVF) are rare spinal vascular abnormalities usually presenting as a slowly progressing myelopathy. Treatment strategies include endovascular, surgical, and adjunct conservative modalities. We report on outcomes and predictors in a cohort treated at our institution. Methods Data were retrieved on clipped and/or coiled sDAVF cases at out Institution between January, 2009 and December, 2019. Sociodemographic, clinical, imaging data, outcomes, follow up and outcome predictors were analyzed. Results Thirty-four patients were identified: 11 female, 23 male; mean age 64.1±11.5 years; mean time of symptom duration 12 (range 1-149) months. The sDAVF locations were: 18 (62.1%) thoracic, 4 (13.8%) lumbar, 4 (13.8%) sacral, and 3 (10%) mixed. All patients had a motor deficit and affected walking and the majority had a sensory deficit, bowel and bladder dysfunction. Fifteen (44.1%) patients underwent surgical treatment, 7 (20.6%) endovascular treatment, 12 (35.3%) patients both. Two (5.9%) patients had a suspected residual at a follow-up angiography. Radiological follow-up of myelopathy showed regression in 19 (55.9%) of cases. Overall, the modified Rankin score (mRS) decreased from 3.7±1.3 pre- to 3.1±1.8 post-procedure: the decrease was significant in the surgical group (3.5±1.8 to 3.1±1.8), not significant in the endovascular (4.0±1.2 to 2.0±1.7) and in the combined group (3.9±1.2 to 3.7±1.6). Fifteen (44.1%) patients showed mRS improvement. Patients who failed to improve had a more extensive myelopathy, as seen on the MRI. Conclusion Patients who underwent surgery had on average significant clinical recovery, while improvement was not significant after embolization and negligible if treatments were combined. Extent of myelopathy seems to be associated with clinical improvement. Key Words: Dural arteriovenous fistula; Endovascular treatment; Outcome; Surgery