Different Types Of Hydrocephalus Research Articles

Infant Hydrocephalus.

Hydrocephalus is a neurosurgical condition that is highly prevalent in pediatric medicine. In the infant population, there is a distinct set of features that all primary pediatricians would benefit from understanding. Infant hydrocephalus can present prenatally on imaging and postnatally with symptomatic enlargement of the head and associated skull features and raised intracranial pressures. The 2 major pathophysiology models of infant hydrocephalus are the bulk flow and the intracranial pulsatility models. The most common acquired forms of hydrocephalus include posthemorrhagic hydrocephalus, postinfectious hydrocephalus, and brain tumor. The most common congenital forms of hydrocephalus include those due to myelomeningocele, aqueductal stenosis, and posterior fossa malformations. There are various evaluation and treatment algorithms for these different types of hydrocephalus, including cerebrospinal fluid shunting and endoscopic third ventriculostomy. The aim of this review was to elaborate on those features of hydrocephalus to best equip primary pediatricians to diagnose and manage hydrocephalus in infants.

Gut microbiota linked to hydrocephalus through inflammatory factors: a Mendelian randomization study.

The gut microbiota (GM) has been implicated in neurological disorders, but the relationship with hydrocephalus, especially the underlying mechanistic pathways, is unclear. Using Mendelian randomization (MR), we aim to discover the mediating role of inflammatory factors in the relationship between GM and hydrocephalus. After removing confounders, univariable and multivariable MR analyses were performed using summary statistics to assess the causal relationships between GM, inflammatory factors (IL-17A and IL-27), and types of hydrocephalus. Meta-analyses were used to reconcile the differences in MR results between different hydrocephalus sources. Finally, mediator MR analyses were applied to determine the mediating effect of inflammatory factors. Various sensitivity analysis methods were employed to ensure the reliability and stability of the results. After correction for P-values, Firmicutes (phylum) (OR, 0.34; 95%CI, 0.17-0.69; P = 2.71E-03, P FDR = 2.44E-02) significantly reduced the risk of obstructive hydrocephalus. The remaining 18 different taxa of GM had potential causal relationships for different types of hydrocephalus. In addition, Firmicutes (phylum) decreased the risk of obstructive hydrocephalus by increasing levels of IL-17A (mediating effect = 21.01%), while Eubacterium ruminantium group (genus) increased the risk of normal-pressure hydrocephalus by decreasing levels of IL-27 (mediating effect = 7.48%). We reveal the connection between GM, inflammatory factors (IL-17A and IL-27), and hydrocephalus, which lays the foundation for unraveling the mechanism between GM and hydrocephalus.

Postoperative Communicating Hydrocephalus Following Grade 2/3 Glioma Resection: Incidence, Timing and Risk Factors.

In diffusely infiltrating gliomas, the maximum extent of tumor resection is an important predictor of overall survival, irrespective of histological or molecular subtype or tumor grade. For glioblastoma WHO grade 4 (GBM), it has been shown that resection-related events, such as ventricular opening and ventriculitis, increase the risk for development of communicating hydrocephalus (CH) requiring cerebrospinal fluid (CSF) diversion surgery. Risk factors for the development and the incidence of hydrocephalus following resection of other types of infiltrating gliomas are less well established. In this study, we evaluated the incidence and timing of occurrence of different types of hydrocephalus and potential risk factors for the development of CH following resection of grade 2 and 3 gliomas. 346 patients who underwent tumor resection (WHO grade 2: 42.2%; 3: 57.8%) at our department between 2006 and 2019 were analyzed retrospectively. For each patient, age, sex, WHO grade, histological type, IDH mutation and 1p/19q codeletion status, tumor localization, number of resections, rebleeding, ventriculitis, ventricular opening during resection and postoperative CSF leak were determined. Uni- as well as multivariate analyses were performed to identify associations with CH and independent risk factors. 24 out of 346 (6.9%) patients needed CSF diversion surgery (implantation of a ventriculoperitoneal or ventriculoatrial shunt) following resection. Nineteen patients (5.5%) had CH, on median, 44 days after the last resection (interquartile range: 18-89 days). Two patients had obstructive hydrocephalus (OH), and three patients had other CSF circulation disorders. CH was more frequent in grade 3 compared to grade 2 gliomas (8.5 vs. 1.4%). WHO grade 3 (odds ratio (OR) 7.5, p = 0.00468), rebleeding (OR 5.0, p = 0.00984), ventriculitis (OR 4.1, p = 0.00463) and infratentorial tumor localization (OR 6.6, p = 0.00300) were identified as significant independent risk factors for the development of post-resection CH. Ventricular opening was significantly associated with CH, but it was not an independent risk factor. Physicians treating brain tumor patients should be aware that postoperative CH requiring CSF shunting occurs not only in GBM but also after resection of lower-grade gliomas, especially in grade 3 tumors. It usually occurs several weeks after resection. Rebleeding and postoperative ventriculitis are independent risk factors.

Postoperative communicating hydrocephalus following glioblastoma resection: Incidence, timing and risk factors.

IntroductionGlioblastoma (GBM) is the most common malignant primary brain tumor. Treatment includes maximally safe surgical resection followed by radiation and/or chemotherapy. However, resection can lead to ventricular opening, potentially increasing the risk for development of communicating hydrocephalus (CH). Complications such as rebleeding and infection may also lead to CH and, eventually, the need for cerebrospinal fluid (CSF) diversion surgery. In this study, we evaluated the incidence of different types of hydrocephalus and potential risk factors for the development of CH following glioblastoma resection.Methods726 GBM patients who underwent tumor resection at our department between 2006 and 2019 were analyzed retrospectively. Potential risk factors that were determined for each patient were age, sex, tumor location, the number of resection surgeries, ventricular opening during resection, postoperative CSF leak, ventriculitis, and rebleeding. Uni- as well as multivariate analyses were performed to identify associations with CH and independent risk factors.Results55 patients (7.6%) needed CSF diversion surgery (implantation of a ventriculoperitoneal or ventriculoatrial shunt) following resection surgery. 47 patients (6.5%) had CH, on median, 24 days after the last resection (interquartile range: 17-52 days). 3 patients had obstructive hydrocephalus (OH) and 5 patients had other CSF circulation disorders. Ventricular opening (odds ratio (OR): 7.9; p=0.000807), ventriculitis (OR 3.3; p=0.000754), and CSF leak (OR 2.3; p=0.028938) were identified as significant independent risk factors for the development of post-resection CH. Having more than one resection surgery was associated with CH as well (OR 2.1; p=0.0128), and frontal tumors were more likely to develop CH (OR 2.4; p=0.00275), while temporal tumors were less likely (OR 0.41; p=0.0158); However, none of those were independent risk factors. Age, sex, or rebleeding were not associated with postoperative CH.ConclusionPostoperative CH requiring CSF shunting is not infrequent following GBM resection and is influenced by surgery-related factors. It typically occurs several weeks after resection. If multiple risk factors are present, one should discuss the possibility of postoperative CH with the patient and maybe even consider pre-emptive shunt implantation to avoid interruption of adjuvant tumor therapy. The incidence of CH requiring shunting in GBM patients could rise in the future.

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.

Anatomic variations of the floor of the third ventricle: Surgical implications for endoscopic third ventriculostomy.

Background: Endoscopic third ventriculostomy (ETV) is currently used as a treatment for different types of hydrocephalus. However, the anatomical endoscopic variants of the third ventricle floor (3VF), as well as their surgical implications, have been underrated. The anatomic variations of the 3VF can influence the technique and the success rate of the ETV. The purpose of this article is to describe the anatomical variations of 3VF, assess their incidence, and discuss the implications for ETV.Methods: Intraoperative videos of 216 patients who underwent ETV between January 2012 and February 2020 at Hospital Infantil Universitario de San José, Bogotá, Colombia were reviewed. One hundred and eighty patients who met the criteria to demonstrate the type of 3VF were selected.Results: 3VF types were classified as follows: (1) Thinned, (2) thickened, (3) partially erased, (4) globular or herniated, and (5) narrowed.Conclusion: Knowledge of anatomical variations of the 3VF is paramount for ETV and it influences the success rate of the procedure.

Quantitative and Qualitative Analysis of CSF Flow Dynamics

Disorders of cerebrospinal fluid (CSF) secretion, dynamics and absorption are common in different illnesses and injuries of the central nervous system (CNS). Nowadays magnetic-resonance tomography (MRI) is the leading research method of CSF dynamics. There are some MRI techniques for both qualitative and quantitative evaluation of CSF dynamic. The assessment of CSF movement is needed to define treatment strategy for patients with different types of hydrocephalus. In this review we have summarized the information about physic basement, area of application of modern MRI techniques. The main attention was paid to modern views on hydrocephalus pathogenesis, pathological CSF flow dynamics in CNS disorders and traumatic brain injury.

Sleep-disordered breathing is frequently associated with idiopathic normal pressure hydrocephalus but not other types of hydrocephalus.

Previous studies have shown sleep-disordered breathing (SDB) to be highly prevalent in patients with idiopathic normal pressure hydrocephalus (iNPH). The current study aimed to estimate and compare the prevalence of SDB in patients with different types of hydrocephalus and test if SDB was associated with changed CO2. We investigated the prevalence of SDB in a prospective cohort of 48 hydrocephalus patients with nocturnal polysomnography (PSG). Twenty-three of the patients also had simultaneous CO2 measurements. The prevalence of SDB was high in patients with iNPH, with moderate-to-severe SDB in 21/22 (96%) of the patients and an apnea-hypopnea index (AHI) of 43.5 (95% CI 33.8-52.2). Patients with pediatric-onset hydrocephalus had moderate-to-severe SDB in 7/16 (44%), with an AHI of 16.1 (95% CI 8.16-23.8). Except for one patient, all patients with adult-onset obstructive hydrocephalus (9/10) had normal respiration or mild SDB with an AHI of 8.4 (95% CI 5.5-10.5). None of the 23 patients measured with CO2 had elevated CO2 associated with SDB and had normal CO2 during sleep, with 40.8 ± 5.5 mmHg, 42.7 ± 4.1 mmHg, 34.5-45.8 mmHg for patients with iNPH, pediatric-onset, and adult-onset, respectively. We found a high prevalence of SDB in patients with iNPH, confirming previous findings. We extended this with the finding that the prevalence of SDB in patients with other types of hydrocephalus is not significantly different from that in the general population. Additionally, we did not find elevations of CO2 associated with SDB or CO2 retention during sleep.

Comparison of Low – Versus Medium-Pressure Shunts in Pediatric Hydrocephalus – A Study of the Children Hospitals, Lahore

Objective: This prospective cross-sectional study was aimed to assess the effectiveness of low-pressure vs. medium-pressure shunts in children with hydrocephalus.
 Material and Methods: 52 children with different types of hydrocephalus were admitted through OPD and Surgical emergency at The Children Hospital, Lahore. All Children were gone through Ultrasonography and CT Brain plain after admission. The pediatric hydrocephalus was resolved into two groups. All patients treated with Chhabra differential pressure VP (ventriculoperitoneal) shunt in either low pressure or medium pressure. CT scans were used to assess the postoperative clinical and radiological outcomes to monitor the ventricle hemispheric ratio (VHR).
 Results: A low-pressure shunt was implanted in 26 individuals, whereas a medium-pressure shunt was implanted in 26 individuals. Patients varied in age from one day to thirteen years old. In group A, the average VHR was 57.58% preoperatively, but it dropped to 42.88% after surgery. Similarly, in group B, the pre-and postoperative VHR was 59.35% and 42.81%, respectively, which was statistically significant. In both groups, the incidence of shunt complications and redo shunt operation were not statistically significant.
 Conclusion: In this study, individuals with pediatric hydrocephalus who had a low-pressure shunt or a medium-pressure shunt had similar outcomes.

Complications of Ventriculoperitoneal Shunts in Children with Pediatric Hydrocephalus a Local Study at Benha University Hospitals

Ventriculoperitoneal shunting is the main way used for extra-thecal cerebrospinal fluid (CSF) diversion. Despite being the main corner stone of treating different types of hydrocephalus, VP shunts has unfortunately a lot of complications making surgeries to treat these complications much more than initial shunt insertions.Methods:It is a clinical retrospective observational study that was conducted on 221 patients wth congenital hydrocephalus of both genders with age ranging from 0 to 18 yrs old who came with symptoms and signs of shunt complications and were primarily shunted at Benha university hospital between 2016 and 2019. A complete clinical assessment was done, history taking, a final diagnosis was made, and a treatment of individual patients was planned accordingly. Patients were followed up till the end of the study post-operatively. Data was analyzed using the SPSS (version 16.0). VP shunt was inserted for 221 patients. 113 (51.1%) patients had various forms of complications. Obstructive complications accounts for the most common complications as they happened in 48 (42.5%) of complicated patients followed by infective complications as they appeared in 27 (24%) patients.Conclusions: Despite .great revolution in the field of neurosurgery in the past 100 years and sincere efforts from neurosurgeons worldwide , shunt complications still common among shunted patients.Background Hydrocephalus is regarded as an imbalance in the formation and absorption of CSF to a sufficient magnitude producing accumulation of CSF fluid with in ventricular system of the brain leading to an elevation of intracranial pressure. Compensatory adjustments especially in very young subjects may occur that may reduce prevailing CSF pressure to normal range on count of functioning brain tissue [1]. Hydrocephalus is the second most common congenital brain malforma-tion [2].Congenital hydrocephalus is type of hydrocephalus that is present or its underlying cause at birth. majority of cases are attributed to aqueductal stenosis , chiarri malformation , dandy walker malformation ,arachnoid cyst. approximately 55% of all cases of congenital hydrocephalus are due to Primary aqueductal stenosis whereas aqueductal stenosis secondary to neoplasm, infection, or hemorrhage accounts for another 5% [4]. Till now , the standard treatment of hydrocephalus is ventriculoperitoneal shunt. The technique of using the peritoneal cavity for CSF absorption in ventriculoperitoneal shunting (VPS) was developed by Kausch in 1908 [3]. Al- though VPS insertion is the most common neurosurgical Procedure done worldwide, complication rates in Children are high ranging from 10% to 100% [11]. The advent of endoscopic third ventriculostomy has gained popularity due to the high complication and failure rates of ventriculoperitoneal shunt [12]. VP shunts are prone to a lot of complications such as mechanical blockage, shunt infection, shunt migration, and various abdominal complications[13].

The Current State of Clinical Trials Studying Hydrocephalus: An Analysis of ClinicalTrials.gov.

IntroductionHydrocephalus is a significant public health concern estimated to affect 380,000 new individuals annually. In addition, it exhibits an increasingly high financial burden for the healthcare industry. Clinical trials are the gold standard for evaluating preventative and therapeutic strategies to bring potential treatments to the forefront of clinical practice.MethodsA study of the ClinicalTrials.gov was conducted in April 2019 to examine all current and previously reported clinical trials studying hydrocephalus. Studies were reviewed to extrapolate information to characterize the current state of research being conducted for hydrocephalus.ResultsIn total, 80 clinical trials met inclusion criteria and were analyzed: 48.8% were observation and 51.2% were interventional. Of those, 55% have been completed while 30.0% are still recruiting, and 15.0% are not yet recruiting. The United States has the most clinical trials (42.0%) and a plurality of trials has a sample size of 0-50 participants. The majority of studies included only adults (53.8%). Of those studies, 54.0% were cohort and the majority were prospective (74.0%). Of the different types of hydrocephalus, normal pressure hydrocephalus and pediatric hydrocephalus have generated the most interest for research comprising a majority of the clinical trial registry. While 44 of the trials are complete, only 20 have published results in peer-reviewed literature highlighting the need for improvement in publishing study results even if the results of the trials are null.ConclusionMost clinical trials to date have pertained to the treatment of normal pressure hydrocephalus and pediatric hydrocephalus. While great advancements have been made for the treatment of hydrocephalus, there remains much room for improvements in therapeutic interventional modalities as well as ensuring the reporting of all undertaken clinical trials.

Prevalence and indication for changing the primary valve opening pressure in ventriculoperitoneal shunts – A single center five years overview

ObjectiveSerious medical conditions of patients in neurosurgery often require ventriculoperitoneal shunting to normalize the intracranial pressure. Neurosurgeons select a valve opening pressure (VOP), whose exceeding causes the shunt to open to drain cerebrospinal fluid (CSF): In most cases a standard pressure is chosen. Whereas some patients fare well with the primary chosen VOP, others require one to several VOP changes. This study aims to evaluate the prevalence and indication for occurring valve pressure-adjustments. Patients and methodsWe obtained information about 343 ventriculoperitoneal shunt implantations in 321 adult patients from 2013 to 2018 in a single center with well-kept electronic health records regarding hydrocephalus types, hydrocephalus etiologies, primary VOP, valve pressure adjustment, time with shunt, time till VOP change, age, sex and shunt type. The data was analyzed using Kaplan-Meier estimator (KME) for the whole patient sample and for subgroups with the primary VOP adjustment defined as event. In the subgroup analysis different types of hydrocephalus, different hydrocephalus etiologies, valve types, both sexes and the patients’ age had been compared by applying Peto-Pike’s log-rank test and cox-regression. ResultsOf the 343 implanted VP shunts in 321 patients, 166 valve pressure adjustments in 101 V P shunts were required during the observed time with a resulting valve pressure-adjustment rate of 0.484 per valve implant. The time till median valve pressure-adjustment was 2.9 years and 38.3% one year after VP shunt placement for the general sample in Kaplan Meier-analysis. The subgroup comparisons between hydrocephalus types, hydrocephalus etiologies, valve types, sexes and the patients’ age did not reveal significant differences applying Peto-Pike’s log-rank test. But the primary chosen valve-pressure of 5 cmH2O is associated with a lower percentage of valve-pressure adjustments, than other initial valve-pressures (Chi2 = 7.9; df = 1; p = 0.0049). ConclusionThis study reveals a valve pressure-adjustment rate of 38.3% after one year for the whole patient collective and similar adjustment rates for different types of hydrocephalus. The primary valve pressure of 5 cmH2O is associated with a lower valve pressure-adjustment rate than other initial valve pressures and therefore 5 cmH2O may be the preferred initial valve pressure for all patients receiving programmable VP shunt insertions with gravitational unit.

Systemic autoimmune diseases complicated with hydrocephalus: pathogenesis and management.

Systemic autoimmune diseases (SAIDs) represent a group of syndromes involving at least two organ systems. Classical SAIDs include connective tissue diseases, vasculitis, and granulomatous diseases, many of which involve the nervous system and result in different neurological manifestations. Hydrocephalus can be a rare but lethal complication of various SAIDs, including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), sarcoidosis, and primary vasculitis. However, the pathogenesis of SAIDs complicated with different types of hydrocephalus is varied and difficult to determine using the existing published data, and various manifestations and expressive forms of the conditions bring a substantial challenge to a timely clinical diagnosis and treatment. The commonly used medical management programs based on the etiology of hydrocephalus are anti-inflammatory or anti-infectious therapies, while surgical management such as ventriculoperitoneal shunts is effective most of the time. Further research should be directed toward improving our understanding of the pathogenesis of these conditions and determining the most effective method for treating this life-threatening condition.

Diagnosis and Differential Diagnosis of Hydrocephalus inAdults.

Purpose Hydrocephalus is caused by an imbalance of production and absorption of cerebrospinal fluid (CSF) or obstruction of its pathways, resulting in ventricular dilatation and increased intracranial pressure. Imaging plays a crucial role in the diagnosis, differential diagnosis and planning of treatment. Methods This review article presents the different types of hydrocephalus und their typical imaging appearance, describes imaging techniques, and discusses differential diagnoses of the different forms of hydrocephalus. Results and Conclusion Imaging plays a central role in the diagnosis of hydrocephalus. While magnetic resonance (MR) imaging is the first-line imaging modality, computed tomography (CT) is often the first-line imaging test in emergency patients. Key points · Occlusive hydrocephalus is caused by obstruction of CSF pathways.. · Malabsorptive hydrocephalus is caused by impaired CSF absorption.. · The MR imaging protocol should always include sagittal high-resolution T2-weighted images.. · When an inflammatory etiology is suspected, imaging with contrast agent administration is necessary.. Citation Format · Langner S, Fleck S, Baldauf J et al. Diagnosis and Differential Diagnosis of Hydrocephalus in Adults. Fortschr Röntgenstr 2017; 189: 728 - 739.

An introduction to hydrocephalus: types, treatments and management

Hydrocephalus is one of the most common neurosurgical conditions or complications. Common treatment options have not changed in decades. However, recent technological advances and improvement in infection rates and outcomes have caused clinicians to rethink attitudes and understanding towards hydrocephalus and patient management. This article is the introduction to a series in which different types of hydrocephalus will be discussed, including various treatment options and recent technological advances that are improving outcomes and diagnostic techniques.

Evaluating the effect of hydrocephalus cause on the manner of changes in the effective parameters and clinical symptoms of the disease

In the present study, the heads of 11 normal subjects and 21 patients affected by hydrocephalus due to three different causes were simulated using fluid–structure interaction (FSI). To validate the results, the calculated diagram of CSF velocity in aqueduct of Sylvius (AS) was compared with the similar velocity diagram measured using Cine PC-MRI for the same subject. After ensuring the agreement of results, other outputs such as CSF pressure were calculated non-invasively using FSI. The intracranial pressure and CSF pressure in AS and behind the optic nerve sheath were in patients 5–5.3 times the value in normal subjects and the ventricular system volume in patients was 10.2–11.1 times the value in normal subjects. However, the difference between the coefficient of variation and the maximum value of pressure and volume in different types of hydrocephalus was small. Furthermore, the difference between CSF stroke volumes in various types of hydrocephalus patients was less than 4.4%. Results showed that the intensity of clinical symptoms was similar in patients with similar CSF pressure and the cause of the hydrocephalus disease didn’t have any significant effect on the intensity of patients’ clinical symptoms and the manner of changes in effective parameters on disease. It was also found that the relation of CSF pressure and volume was 16.7% greater in patients with non-communicating hydrocephalus than in patients with communicating hydrocephalus. These results enhance the insight into hydrocephalus bio-mechanism and can help to choose the proper treatment method for hydrocephalus patients.

Characterisation of the complexity of intracranial pressure signals measured from idiopathic and secondary normal pressure hydrocephalus patients.

Hydrocephalus is a condition characterised by enlarged cerebral ventricles, which in turn affects intracranial pressure (ICP); however, the mechanisms regulating ICP are not fully understood. A nonlinear signal processing approach was applied to ICP signals measured during infusion studies from patients with two forms of hydrocephalus, in a bid to compare the differences. This is the first study of its kind. The two forms of hydrocephalus were idiopathic normal pressure hydrocephalus (iNPH) and secondary normal pressure hydrocephalus (SH). Following infusion tests, the Lempel-Ziv (LZ) complexity was calculated from the iNPH and SH ICP signals. The LZ complexity values were averaged for the baseline, infusion, plateau and recovery stages of the tests. It was found that as the ICP increased from basal levels, the LZ complexities decreased, reaching their lowest during the plateau stage. However, the complexities computed from the SH ICP signals decreased to a lesser extent when compared with the iNPH ICP signals. Furthermore, statistically significant differences were found between the plateau and recovery stage complexities when comparing the iNPH and SH results (p = 0.05). This Letter suggests that advanced signal processing of ICP signals with LZ complexity can help characterise different types of hydrocephalus in more detail.

Intracranial pressure for the characterization of different types of hydrocephalus: A Permutation Entropy study.

Hydrocephalus is a condition characterized by altered cerebrospinal fluid (CSF) dynamics and chronic rises in intracranial pressure (ICP). However, the reason why hydrocephalic physiologies fail to inhibit dangerously high ICP levels is not known. Infusion studies are used to raise ICP and evaluate CSF circulation disorders. In this pilot study, ICP signals recorded during infusion tests from 33 patients with normal pressure hydrocephalus and 36 patients having developed a secondary form of normal pressure hydrocephalus were characterized using Permutation Entropy (PE), a symbolic non-linear method to quantify complexity. Each ICP signal was divided into four epochs--baseline (before infusion begins), infusion, plateau, and recovery (after infusion has stopped)--and the mean PE was calculated for each epoch. Statistically significant differences were found between PE for most epochs (p<;0.00833, Bonferroni-corrected Wilcoxon tests), with a significant decrease in the plateau phase. However, differences between PE for normal pressure and secondary hydrocephalus were not significant. Results suggest that the increase in ICP during infusion studies is associated with a significant decrease in PE. PE analysis of ICP signals could be useful for increasing our understanding of CSF dynamics in normal pressure hydrocephalus.

Neuroendoscopic surgery in hydrocephalus

Abstract Hydrocephalus represents one of the most frequent pathologic entities requiring neurosurgical intervention. Even in present times the treatment of hydrocephalus is a highly debated subject. Neuroendoscopy is one of the technique posibility. The present study includes patients with different types of hydrocephalus classified according to imagistic criteria (MRI). Neuroendoscopic therapeutic options are presented for different types of hydrocephalus and the postoperative results of these procedures are revealed by imaging. In conclusion, we consider neuroendoscopy useful in each type of hydrocephalus.

Choroid plexus differences in rats with spontaneous and induced hydrocephalus

Background In hydrocephalus alterations of the brain structures have been described, among them: cortical displacement, cerebrospinal fluid composition alterations and circumventricular structure variations are described and many of these variations could be cause or consequences of the hydrocephalus. The protein p73 is a member of a family of transcription factors and equilibrium between p73 isoforms is necessary for the normal development of the brain and the maturation of the neuroepithelium. On the other hand, the p73 deficiency produces many alterations in the brain that include hydrocephalus. The purpose of this work was to analyze the alteration of the choroid plexus (CP) in different types of hydrocephalus.