Cerebrospinal Fluid Disorders Research Articles

Cycle-dependent sex differences in expression of membrane proteins involved in cerebrospinal fluid secretion at rat choroid plexus

BackgroundFemale sex is a known risk factor of brain disorders with raised intracranial pressure (ICP) and sex hormones have been suggested to alter cerebrospinal fluid (CSF) dynamics, thus impairing ICP regulation in CSF disorders such as idiopathic intracranial hypertension (IIH). The choroid plexus (CP) is the tissue producing CSF and it has been hypothesized that altered hormonal composition could affect the activity of transporters involved in CSF secretion, thus affecting ICP. Therefore, we aimed to investigate if expression of various transporters involved in CSF secretion at CP were different between males and females and between females in different estrous cycle states. Steroid levels in serum was also investigated.MethodsFemale and male rats were used to determine sex-differences in the genes encoding for the transporters Aqp1 and 4, NKCC1, NBCe2, NCBE; carbonic anhydrase enzymes II and III (CA), subunits of the Na+/K+-ATPase including Atp1a1, Atp1b1 and Fxyd1 at CP. The estrous cycle stage metestrus (MET) and estrous (ES) were determined before euthanasia. Serum and CP were collected and subjected to RT-qPCR analysis and western blots. Serum was used to measure steroid levels using liquid chromatography tandem mass spectrometry (LC–MS/MS).ResultsSignificant differences in gene expression and steroid levels between males and ES females were found, while no differences were found between male and MET females. During ES, expression of Aqp1 was lower (p < 0.01) and NKCC1 was higher in females compared to males. CAII was lower while CAIII was higher in ES females (p < 0.0001). Gene expression of Atp1a1 was lower in ES compared to male (p = 0.0008). Several of these choroidal genes were also significantly different in MET compared to females in ES. Differences in gene expression during the estrus cycle were correlated to serum level of steroid hormones. Protein expression of AQP1 (p = 0.008) and CAII (p = 0.035) was reduced in ES females compared to males.ConclusionsThis study demonstrates for the first time that expression at CP is sex-dependent and markedly affected by the estrous cycle in female rats. Further, expression was related to hormone levels in serum. This opens a completely new avenue for steroid regulation of the expression of CSF transporters and the close link to the understanding of CSF disorders such as IIH.

The initial intracranial pressure spike phenomenon.

Elective use of intraparenchymal intracranial pressure (ICP) monitoring is a valuable resource in the investigation of hydrocephalus and other cerebrospinal fluid disorders. Our preliminary study aims to investigate ICP changes in the immediate period following dural breach, which has not yet been reported on. This is a prospective cohort study of patients undergoing elective ICP monitoring, recruited between March and May 2022. ICP readings were obtained at opening and then at 5-min intervals for a 30-min duration. Ten patients were recruited, mean age 45 years, with indications of a Chiari malformation (n = 5), idiopathic intracranial hypertension (n = 3) or other ICP-related pathology (n = 2). Patients received intermittent bolus sedation (80%) vs general anaesthesia (20%). Mean opening pressure was 22.9 mmHg [± 6.0], with statistically significant decreases present every 5 min, to a total reduction of 15.2 mmHg at 20 min (p = < 0.0001), whereafter the ICP plateaued with no further statistical change. Our results highlight an intracranial opening pressure 'spike' phenomenon. This spike was 15.2 mmHg higher than the plateau, which is reached at 20 min after insertion. Several possible causes exist which require further research in larger cohorts, including sedation and pain response. Regardless of causation, this study provides key information on the use of ICP monitoring devices, guiding interpretation and when to obtain measurements.

A Neuro-Ophthalmologist's Guide to Advances in Intracranial Pressure Measurements.

Cerebrospinal fluid disorders have a wide-ranging impact on vision, headache, cognition and a person's quality of life. Due to advances in technology and accessibility, intracranial pressure measurement and monitoring, usually managed by neurosurgeons, are being employed more widely in clinical practice. These developments are of direct importance for Ophthalmologists and Neurologists because the ability to readily measure intracranial pressure can aide management decisions. The aim of this review is to present the emerging evidence for intracranial pressure measurement methods and interpretation that is relevant to Neuro-ophthalmologists.

Evaluation of Miethke M.scio Device Implantation for Intracranial Pressure Monitoring in Patients with Cerebrospinal Fluid Disorders

Patients with complex shunt-related problems and varying diagnoses of cerebrospinal fluid (CSF) disturbance can present with headache and clinical symptoms that may be difficult to relate to underdrainage or overdrainage. Telemetric intracranial pressure (ICP) monitoring may assist in evaluating individual patients and assessing shunt function and adjustment. We report a case series of patients receiving a Miethke M.scio sensor. Between June 2016 and August 2021, 14 patients older than 18 years with different diagnoses underwent ventriculoperitoneal shunt surgery and received a Miethke M.scio sensor. Patients had idiopathic intracranial hypertension (n= 3), obstructive hydrocephalus caused by tumors (n= 4), and malformations (n= 5). Headaches (71%) and visual impairment (50%) were the most common symptoms before surgery and 65% of the symptoms were improved after surgery. In total, 25 measurements were made and 11 of these led to changes in the shunt settings. Postoperative measurements were taken in 8 patients and the most common indication of ICP measurement was headache and/or control of the shunt settings. The Miethke M.scio is a safe and valuable device to use in shunt-treated patients, in particular those expected to need assessment of ICP monitoring postoperatively. Repeated ICP measurements can also assist in personalized adjustment of the shunt setting to optimize CSF flow in this diverse patient group. Future studies should include a standardized protocol with ICP measurements correlated to the symptoms and cause of CSF disturbances to provide better understanding of the dynamics of the ICP in each patient.

Endoscopic third ventriculostomy for the management of children with cerebrospinal fluid disorders, ventriculomegaly, and associated Chiari I malformation

Objectives: Our objective was to review the outcomes of children with CIM and associated cerebrospinal fluid (CSF) disorders and ventriculomegaly undergoing endoscopic third ventriculostomy (ETV) as a primary intervention.Materials and methods: A retrospective, single-center, observational cohort study was conducted of consecutive children with CIM with associated CSF disorders and ventriculomegaly treated first by ETV between January 2014 and December 2020.Results: Raised intracranial pressure symptoms were the most frequent in ten patients, followed by posterior fossa and syrinx symptoms in three cases. One patient had a later stoma closure and required a shunt insertion. The success rate of the ETV in the cohort was 92% (11/12). There was no surgical mortality in our series. No other complications were reported. The median herniation of the tonsils was not statistically different in the pre vs. post-operative MRI (1.14 vs. 0.94, p=0.1). However, the median Evan’s index (0.4 vs. 0.36, p<0.01) and the median diameter of the third ventricle (1.35 vs. 0.76, p<0.01) were statistically different between the two measurements. The preoperative length of the syrinx did not change significantly compared with the postoperative (5 vs. 1; p=0.052); nevertheless, the median transverse diameter of the syrinx did improve significantly after the surgery (0.75 vs. 0.32, p=0.03).Conclusions: Our study supports ETV's safety and effectiveness for managing children with CSF disorders, ventriculomegaly, and associated CIM

Human parasagittal dura is a potential neuroimmune interface

Parasagittal dura (PSD) is located on both sides of the superior sagittal sinus and harbours arachnoid granulations and lymphatic vessels. Efflux of cerebrospinal fluid (CSF) to human PSD has recently been shown in vivo. Here we obtain PSD volumes from magnetic resonance images in 76 patients under evaluation for CSF disorders and correlate them to age, sex, intracranial volumes, disease category, sleep quality, and intracranial pressure. In two subgroups, we also analyze tracer dynamics and time to peak tracer level in PSD and blood. PSD volume is not explained by any single assessed variable, but tracer level in PSD is strongly associated with tracer in CSF and brain. Furthermore, peak tracer in PSD occurs far later than peak tracer in blood, implying that PSD is no major efflux route for CSF. These observations may indicate that PSD is more relevant as a neuroimmune interface than as a CSF efflux route.

The Effect of COVID-19 in a University Hospital Neurosurgery Clinic Comparison to Prepandemic Period: A Retrospective Study with 6 months of Data

The coronavirus disease 2019 (COVID-19) pandemic affected all countries' health systems and people's lifestyles. In this study, we aimed to investigate its effects in a university hospital neurosurgery clinic. The 2019year's 6months' data as a prepandemic period compared to the 2020year's same period as a pandemic date. Demographic data were collected. Operations were divided into seven groups: tumor, spinal, vascular, cerebrospinal fluid disorders, hematoma, local, and minor surgery, respectively. We classified the hematoma cluster into subgroups to evaluate the etiology: epidural, acute subdural, subarachnoid hemorrhage, intracerebral hemorrhage, depressed skull fractures, and others. Patients' COVID-19 test results were collected. Total operations decreased from 972 to 795 (Δ18.2%) during the pandemic. All groups, except minor surgery cases, decreased compared to the prepandemic period. Also, vascular procedures for females increased during the pandemic period. While focusing on the hematoma subgroups, there was decreasing in epidural and subdural hematomas, depressed skull fractures, and total case numbers; an increase in subarachnoid hemorrhage and intracerebral hemorrhage. Overall mortality significantly increased to 9.6% from 6.8% during the pandemic (P= 0.033). Eight (1.0%) of 795 patients were COVID-19-positive; three of them died. Neurosurgery residents and academicians were unsatisfied with decreased number of operations, training, and research productivity. The pandemic and restrictions affected negatively the health system and people's access to healthcare. Our retrospective observational study aimed to evaluate these effects and take lessons for the next similar situations. People's access to health care should be considered when lockdown restrictions.

Cognitive functioning in patients with Chiari malformation type I and relationship with neurological manifestations

BACKGROUND. The symptom complex of Chiari malformation type I (CMI) is traditionally characterized by the set of cerebrospinal fluid disorders, coordination disorders, brainstem and myelopathic manifestations. Cognitive impairments, as manifestations of CMI, are little-known area. Study of the characteristics of cognitive status in patients with CMI and analysis of relationship between cognitive phenotype and severity of neurological manifestations can become basis for the formation of a more detailed understanding of this pathology.&#x0D; AIM. The aim was to characterize complex of the neuro-neuropsychological spectrum symptoms and their relationship in patients with CMI.&#x0D; MATERIALS AND METHODS. The main group included 105 adult patients with CMI 74 (70.5%) men and 31 (29.5%) women aged 25.616.89 years. The control group included 50 patients without signs of CMI, other organic brain pathology and cognitive disorders of known etiology 31 (62%) men and 19 (38%) women aged 26.365.00 years. The neuroimaging verification of CMI was performed by magnetic resonance imaging of the brain. Clinical assessment consisted of the collecting complaints, anamnestic information and detailed neurological examination. Comprehensive neuropsychological testing was performed by using MMSE, MoCA and TMT (A and B).&#x0D; RESULTS. Dissociation was noted between prevalence of the typical subjective symptoms and frequency of the objective neurological manifestations in patients with CMI. Among the most frequent subjective symptoms in CMI were headaches and neck pain, asthenia, disorders of the coordination sphere, as well as subjective signs of cognitive dysfunction. Objective neurological deficits were mainly represented by cerebellar disorders. Signs of cognitive dysfunction in the form of memory and attention disorders described by patients with CMI in 20% cases were confirmed by the results of complex neuropsychological testing in comparison with a group of healthy respondents. The relationship of the cognitive deficits with presence and severity of the objective neurological, mainly cerebellar, manifestations in patients with CMI was revealed.&#x0D; CONCLUSIONS. The relationship of cognitive dysfunction with the presence and severity of objective neurological, mainly cerebellar, disorders indicate the complexity of neurological and neuropsychological manifestations in CMI. These data suggest an important role of the disturbed anatomy of the cerebellum and its connections with the cerebral cortex in the pathophysiology of a wide range of major clinical manifestations of CMI.

Surgical management of Chiari malformation type 1 associated to MCAP syndrome and study of cerebellar and adjacent tissues for PIK3CA mosaicism

BackgroundSubjects with Megalencephaly-Capillary Malformation-Polymicrogyria syndrome (MCAP) can present with a Chiari Malformation Type 1 and resulting alterations in cerebrospinal fluid (CSF) dynamics, which may require surgical treatment. The aim of this paper is to describe the features of children with MCAP who underwent surgical decompression for CM1, and to explore the PIK3CA variant allele frequency (VAF) identified in cerebellar parenchyma and other adjacent structures. MethodsThis study reviewed two cases of children with CM1 and MCAP who underwent surgical decompression treatment. These two cases were part of a national cohort of 12 MCAP patients who had CM1, due to their surgical eligibility. Tissue samples were obtained from the cerebellar tonsils and adjacent anatomical structures during the surgical procedures. Samples were then subsequently analyzed for PIK3CA postzygotic variants. ResultsIn both cases, alterations in CSF dynamics, specifically hydrocephalus and syringomyelia, were observed and required surgical treatment. PIK3CA targeted sequencing determined the VAF of the postzygotic variant in both cerebellar and adjacent bone/connective tissues. DiscussionThe recognition of a CM1 comorbidity in MCAP patients is of paramount importance when considering personalized treatment options, especially because these patients are at higher risk of developing complications during surgical decompression surgery. The variable PIK3CA VAF identified in the different analyzed tissues might help explain the heterogeneous nature and severity of anomalies observed in the volume of the posterior fossa structures in MCAP patients and associated CSF and venous disorders.

First Experience With Postoperative Transcranial Ultrasound Through Sonolucent Burr Hole Covers in Adult Hydrocephalus Patients.

Managing patients with hydrocephalus and cerebrospinal fluid (CSF) disorders requires repeated head imaging. In adults, it is typically computed tomography (CT) or less commonly magnetic resonance imaging (MRI). However, CT poses cumulative radiation risks and MRI is costly. Ultrasound is a radiation-free, relatively inexpensive, and optionally point-of-care alternative, but is prohibited by very limited windows through an intact skull. To describe our initial experience with transcutaneous transcranial ultrasound through sonolucent burr hole covers in postoperative hydrocephalus and CSF disorder patients. Using cohort study design, infection and revision rates were compared between patients who underwent sonolucent burr hole cover placement during new ventriculoperitoneal shunt placement and endoscopic third ventriculostomy over the 1-year study time period and controls from the period 1 year before. Postoperatively, trans-burr hole ultrasound was performed in the clinic, at bedside inpatient, and in the radiology suite to assess ventricular anatomy. Thirty-seven patients with sonolucent burr hole cover were compared with 57 historical control patients. There was no statistically significant difference in infection rates between the sonolucent burr hole cover group (1/37, 2.7%) and the control group (0/57, P = .394). Revision rates were 13.5% vs 15.8% (P = 1.000), but no revisions were related to the burr hole or cranial hardware. Trans-burr hole ultrasound is feasible for gross evaluation of ventricular caliber postoperatively in patients with sonolucent burr hole covers. There was no increase in infection rate or revision rate. This imaging technique may serve as an alternative to CT and MRI in the management of select patients with hydrocephalus and CSF disorders.

The UK CSF Disorders Day 2022

ABSTRACT The annual United Kingdom cerebrospinal fluid disorders meeting made its return to the University of Birmingham, United Kingdom, following the break in proceedings due to the coronavirus pandemic. Cerebrospinal fluid disorders require a multi-disciplinary approach with inputs from the neurological, neuro-ophthalmological, neuroradiological, and neurosurgical specialities. The annual meeting presented the newest concepts underpinning idiopathic intracranial hypertension pathophysiology and the advances in intracranial pressure monitoring and treatment.

The Birmingham Standardized Idiopathic Intracranial Hypertension Shunt Protocol: Technical Note

Insertion of cerebrospinal fluid (CSF) shunts in patients with idiopathic intracranial hypertension (IIH) is challenging mainly due to the small ventricles and phenotypical body habitus. In this report the authors present their surgical protocol for insertion of a ventriculoperitoneal shunt (VPS) in patients with IIH and the associated revision rates. The protocol comprises the following: shuntsurgery by neurosurgeons with expertise in CSF disorders; a frontal VPS usually right sided but left sided if the left ventricle is bigger; use of the proGAV 2.0 valve with gravitational unit, set at 10 and the M.scio telemetric sensor; cannulation of the ventricle with StealthStation EM navigation system; and laparoscopic insertion of the peritonealcatheter. The authors describe the protocol and rationale and evidence behind each component and presentthe results of a prospective analysis on revision rates. The protocol has been implemented since 1 July, 2019, and by 28 February, 2022, sixty-two patients with IIH had undergone primary VPS insertion. The 30-day revision rate was 6.5%, and overall 11.3% of patients underwent revision during the study period, which compares favorably with the literature. The etiology for early failures was related to the surgical technique. The components of the Birmingham standardized IIH shunt protocol are evidence based and address the technical challenges of CSF diversion in patients with IIH. This protocol is associated with a low revision rate, and the authors recommend standardization for CSF shunting in IIH.

The role of the pediatric neurosurgeon in abusive head injuries: a survey of members of the International Society for Pediatric Neurosurgery.

Pediatric neurosurgeons are at the forefront of the clinical management of abusive head injuries (AHI) all over the world. However, the discrepancies regarding medical practice and legal requirements in different centers have not been assessed before. We decided to perform an online survey among members of the International Society for Pediatric Neurosurgery (ISPN) regarding their activity, their usual clinical practice regarding the medical and legal management of AHI, and their involvement in judiciary proceedings, research, and prevention campaigns. Ninety members of the ISPN participated in the survey, representing 26% of the registered members. Most responders were senior pediatric neurosurgeons practicing in a university hospital. Their responses show great homogeneity regarding surgical, intensive care, and legal management. We also noted the widespread use of invasive intracranial pressure monitoring and decompressive craniotomy. By contrast, the responses show great disparity regarding the circuit of patients. This disparity may be an obstacle to the collection of data and clinical research, as well as for the involvement of neurosurgeons in multidisciplinary evaluation. A minority of neurosurgeons were engaged in research and actions of prevention. Pediatric neurosurgeons play a pivotal role in the diagnosis and medical management of AHI. Because of their proficiency in head trauma and cerebrospinal fluid disorders, it is desirable that they become more implicated in multidisciplinary meetings, medical expertise, and scientific research, as well as actions of prevention.

Patients awaiting surgery for neurosurgical diseases during the first wave of the COVID-19 pandemic in Spain: a multicentre cohort study

ObjectivesThe large number of infected patients requiring mechanical ventilation has led to the postponement of scheduled neurosurgical procedures during the first wave of the COVID-19 pandemic. The aims of this...

Ultrasonography for Serial Monitoring and Management of Cerebrospinal Fluid Dynamic Disorders After Decompressive Craniectomy.

Decompressive craniectomy (DC) is widely used to treat intracranial hypertension following severe head injury. However, impairments of cerebrospinal fluid (CSF) hydrodynamics such as hydrocephalus and subdural effusion are common complications that occur after DC. Therefore, monitoring of intracranial pressure is a staple of neurocritical care post-DC. The aim of this study was to assess the usefulness of transcranial duplex sonography (TDS) for serial monitoring and management of CSF disorders after DC. A total of 100 patients who underwent DC between June 2016 and May 2019 were recruited for the study. Transcranial duplex sonography examinations were performed between 1-day and 1-year post-DC. Transcranial duplex sonography was mainly used for monitoring changes in ventricle size and morphology, and also to monitor intraventricular hemorrhage, hydrocephalus, intracranial hygromas, and ventricle changes during CSF release procedures. A total of 456 TDS examinations were performed on patients after DC. Of these, 402 were performed in the neuro-intensive care unit. Two patients had intraventricular hemorrhage and underwent TDS-guided external ventricular drainage. Twenty-nine patients were diagnosed with hydrocephalus. The results of TDS were consistent with those of cranial computed tomography. Three cases of ventriculoperitoneal shunt and 1 case of lumbar peritoneal shunt underwent valve pressure reset according to TDS, to obtain satisfactory ventricle size. Transcranial duplex sonography was used to monitor ventricle changes and control drainage volume during CSF release procedures, including 2 external ventricular drainage, 6 external lumbar drainage, and 10 lumbar punctures. Eighteen patients were detected with single or multiple intracranial effusions, including 16 subdural hygromas, 5 longitudinal fissure hygromas, and 6 brain cysts. Transcranial duplex sonography can efficiently help monitor changes in ventricle size and morphology and intracranial effusions. Due to its noninvasive nature, suitability for bedside application, real-time, and inexpensiveness, TDS can significantly replace cranial computed tomography and become part of the patient's daily inspection work after DC.

Population pharmacokinetic modeling of CSF to blood clearance: prospective tracer study of 161 patients under work-up for CSF disorders

BackgroundQuantitative measurements of cerebrospinal fluid to blood clearance has previously not been established for neurological diseases. Possibly, variability in cerebrospinal fluid clearance may affect the underlying disease process and may possibly be a source of under- or over-dosage of intrathecally administered drugs. The aim of this study was to characterize the cerebrospinal fluid to blood clearance of the intrathecally administered magnetic resonance imaging contrast agent gadobutrol (Gadovist, Bayer Pharma AG, GE). For this, we established a population pharmacokinetic model, hypothesizing that cerebrospinal fluid to blood clearance differs between cerebrospinal fluid diseases.MethodsGadobutrol served as a surrogate tracer for extra-vascular pathways taken by several brain metabolites and drugs in cerebrospinal fluid. We estimated cerebrospinal fluid to blood clearance in patients with different cerebrospinal fluid disorders, i.e. symptomatic pineal and arachnoid cysts, as well as tentative spontaneous intracranial hypotension due to cerebrospinal fluid leakage, idiopathic intracranial hypertension, or different types of hydrocephalus (idiopathic normal pressure hydrocephalus, communicating- and non-communicating hydrocephalus). Individuals with no verified cerebrospinal fluid disturbance at clinical work-up were denoted references.ResultsPopulation pharmacokinetic modelling based on 1,140 blood samples from 161 individuals revealed marked inter-individual variability in pharmacokinetic profiles, including differences in absorption half-life (time to 50% of tracer absorbed from cerebrospinal fluid to blood), time to maximum concentration in blood and the maximum concentration in blood as well as the area under the plasma concentration time curve from zero to infinity. In addition, the different disease categories of cerebrospinal fluid diseases demonstrated different profiles.ConclusionsThe present observations of considerable variation in cerebrospinal fluid to blood clearance between individuals in general and across neurological diseases, may suggest that defining cerebrospinal fluid to blood clearance can become a useful diagnostic adjunct for work-up of cerebrospinal fluid disorders. We also suggest that it may become useful for assessing clearance capacity of endogenous brain metabolites from cerebrospinal fluid, as well as measuring individual cerebrospinal fluid to blood clearance of intrathecal drugs.

Surgical Implications of Internal Jugular Stenosis in a Patient Undergoing Resection of a Craniocervical Junction Meningioma

Internal jugular vein (IJV) stenosis is being increasingly associated with certain neurological conditions, including benign intracranial hypertension, cerebrospinal fluid (CSF) disorders, multiple sclerosis and Alzheimer's disease. The role of surgery in IJV stenosis have typically been to manage the associated CSF disorders, or with IJV stents. We describe a case of a patient incidentally found to have bilateral possible IJV stenosis with dilated paraspinal collateral venous channels during pre-operative CT angiogram for a symptomatic craniocervical junction meningioma, and the associated operative considerations.

Reassessing accuracy of blood cell correction factor for traumatic lumbar puncture

ObjectiveThis study assessed the utility of correction formulas for procedural peripheral blood admixture with cerebrospinal fluid (CSF) in adult patients using in vitro addition of peripheral blood. MethodsParticipants from the Johns Hopkins CSF Disorders Center were recruited if greater than 18 years old, not acutely ill, and able to tolerate lumbar puncture (LP). Peripheral blood was added in vitro to acellular CSF and then cellular concentration and protein were quantified. ResultsCorrection formulas for white blood cell (WBC) count determined by linear regression for samples with more than 100,000 RBCs per uL were inaccurate. Linear correction formulas close to 1 WBC per 1000 red blood cells (RBCs) were more precise than the formula based on peripheral blood WBC to RBC ratio. Correction formulas for protein level derived by linear regression had minimal error. DiscussionThis study confirms in a controlled manner that CSF admixture with peripheral blood cannot always be reliably corrected for in a predictable manner. Use of correction formulas for protein level and for WBC count when CSF admixture with peripheral blood has RBCs less than 10,000 per microliter is possibly useful but will need to be assessed in larger studies that can confirm diagnostic utility.

Experience of Application of Magnetic Resonance Myelography Methods in Patients with Neurological and Neurosurgical Pathology

Purpose — to study the possibilities of clinical application of MR-myelography techniques in static and dynamic modes in patients with various neurological and neurosurgical pathologies accompanied by CSF dynamics disorders. On the Philips 1.5 and 3.0 T MRI scanners, an extended protocol for examination of patients with cerebrospinal fluid disorders was presented. The protocol includes, in addition to routine sequences (T1-, T2-WI, FLAIR), thin-slice MP-myelography in a static mode (CSF-DRIVE, 3DMYUR) with soft tissues signal suppression. Also, a cinema-technique of MR myelography (CSF-PCA) in the optimal projection and a phase-contrast method with a quantitative assessment of the cerebrospinal fluid flow at the pathology level and at adjacent levels were performed. The assessment of the diagnostic significance of the proposed research protocol was carried out. The extended study protocol was applied in patients with idiopathic normotensive hydrocephalus, obstructive hydrocephalus, Chiari malformation type I, in patients with syringomyelia at the level of the cervical spinal cord and showed high efficiency in assessing of cerebrospinal fluid dynamics in patients with a neurological and neurosurgical profile. The use of extended approach allows to more fully evaluate the state of the cerebrospinal fluid system, the patency of the cerebrospinal fluid (the presence of additional septa / membranes, partial / complete stenosis and narrowing), as well as preand postoperative morpho-functional changes.

Transmantle and transvenous pressure gradients in cerebrospinal fluid disorders.

Hydrocephalus is the symptomatic endpoint of a variety of disease processes. Simple hydrodynamic models have failed to explain the entire spectrum of cerebrospinal fluid (CSF) disorders. Physical principles argue that for ventricles to expand, they must be driven by a force, Fishman's transmantle pressure gradient (TMPG). However, the literature to date, reviewed herein, is heterogenous and fails to consistently measure a TMPG. The venous system, like CSF, traverses the cerebral mantle, and thus analogous transparenchymal and transvenous pressure gradients have been described, reliant on the differential haemodynamics of the deep and superficial venous systems. Interpreting CSF disorders through these models provides new insights into the possible pathophysiological mechanisms underlying these diseases. However, until more sophisticated testing is performed, these models should remain heuristics.