Post-hemorrhagic hydrocephalus: Recent advances and new therapeutic insights

Characteristics of Post-traumatic Shunt-dependent Hydrocephalus After Decompressive Craniectomy: Are Computed Tomography Scoring Systems Predictors?

OBJECTIVE

Traumatic brain injury (TBI) significantly contributes to morbidity rates. While computed tomography (CT) scoring systems have been recognized as predictive factors for TBI outcomes, their association with shunt dependency in patients undergoing decompressive craniectomy (DC) has not been investigated. This study aimed to evaluate the predictive utility of CT scoring systems concerning shunt-dependent hydrocephalus in patients post-DC for TBI.

METHODS

In this retrospective study, we enrolled 162 patients who underwent DC and survived more than 7 days following TBI. The pre-DC CT scans were evaluated using the Marshall, Rotterdam, and Helsinki CT scoring systems. The primary event of interest was shunt-dependent hydrocephalus during the follow-up period, with unfavorable outcomes denoted by a Glasgow Outcome Scale score ranging from 1 to 3.

RESULTS

Analysis of the CT scans showed that the Rotterdam scores had a mean of 4.81 ± 0.91 for the group with shunt-dependent hydrocephalus and 4.41 ± 1.24 for the non-shunt-dependent hydrocephalus group (P = 0.033). However, multivariate logistic regression revealed no significant correlation between the Rotterdam CT score and shunt-dependent hydrocephalus, showing an odds ratio of 1.09 and a 95% confidence interval of 0.71 to 1.67 (P = 0.684). Notably, the Kaplan-Meier outcome curves highlighted a pronounced difference between groups based on shunt dependency (log-rank test: P = 0.012).

CONCLUSIONS

The CT scoring systems proved insufficient for predicting shunt-dependent hydrocephalus following DC for TBI. However, our observations underscore a significant correlation between post-traumatic shunt dependency after DC and an increased incidence of unfavorable outcomes during long-term follow-up.

Modified ventriculoperitoneal shunt applied to temporary external ventricular drainage

External ventricular drainage (EVD) is a common procedure in neurosurgical practice. Presently, the three methods used most often include direct EVD (dEVD), long-tunneled external ventricular drains (LTEVDs), and EVD via the Ommaya reservoir (EVDvOR). But they possess drawbacks such as limited duration of retention, vulnerability to iatrogenic secondary infections, and challenges in regulating drainage flow. This study aimed to explore the use of a modified ventriculoperitoneal shunt (mVPS)-the abdominal end of the VPS device was placed externally-as a means of temporary EVD to address the aforementioned limitations. This retrospective cohort study, included 120 cases requiring EVD. dEVD was performed for 31 cases, EVDvOR for 54 cases (including 8 cases with previously performed dEVD), and mVPS for 35 cases (including 6 cases with previously performed EVDvOR). The one-time success rate (no need for further other EVD intervention) for dEVD, EVDvOR, and mVPS were 70.97%, 88.89%, and 91.42%, dEVD vs EVDvOR (P < 0.05), dEVD vs mVPS (P < 0.05), EVDvOR vs mVPS (P > 0.05). Puncture needle displacement or detachment was observed in nearly all cases of EVDvOR, while no such complications have been observed with mVPS. Apart from this complication, the incidence of postoperative complications was 35.48%, 14.81%, and 8.5%, dEVD vs EVDvOR (P < 0.05), dEVD vs mVPS (P < 0.05), EVDvOR vs mVPS (P > 0.05). Mean postoperative retention for EVD was 14.68 ± 9.50 days, 25.96 ± 15.14 days, and 82.43 ± 64.45 days, respectively (P < 0.001). In conclusion, mVPS significantly extends the duration of EVD, which is particularly beneficial for patients requiring long-term EVD.

Therapy management and outcome of acute hydrocephalus secondary to intraventricular hemorrhage in adults

BACKGROUND

Intraventricular hemorrhage (IVH) refers to bleeding within the brain's ventricular system, and hydrocephalus is a life-threatening complication of IVH characterized by increased cerebrospinal fluid accumulation in the ventricles resulting in elevated intracranial pressure. IVH poses significant challenges for healthcare providers due to the complexity of the underlying pathophysiology and lack of standardized treatment guidelines. Herein, we performed a systematic review of the treatment strategies for hydrocephalus secondary to IVH.

METHODS

This systematic review was prospectively registered with PROSPERO (CRD42023450786). The search was conducted in PubMed, Cochrane Library, and Web of Science on July 15, 2023. We included original studies containing valid information on therapy management and outcome of hydrocephalus secondary to primary, spontaneous, and subarachnoid or intracranial hemorrhage following IVH in adults that were published between 2000 and 2023. Glasgow Outcome Scale (GOS) or modified Ranking Scale (mRS) scores during follow-up were extracted as primary outcomes. The risk of bias was assessed using the Newcastle-Ottawa Scale for Cohort Studies or Cochrane Risk of Bias 2.0 Tool.

RESULTS

Two hundred and seven patients from nine published papers, including two randomized controlled trials, were included in the analysis. The GOS was used in five studies, while the mRS was used in four. Seven interventions were applied, including craniotomy for removal of hematoma, endoscopic removal of hematoma with/without endoscopic third ventriculostomy (ETV), traditional external ventricular drainage (EVD), and various combinations of EVD, lumbar drainage (LD), and intraventricular fibrinolysis (IVF). Endoscopic removal of hematoma was performed in five of nine studies. Traditional EVD had no obvious benefit compared with new management strategies. Three different combinations of EVD, LD, and IVF demonstrated satisfactory outcomes, although more studies are required to confirm their reliability. Removal of hematoma through craniotomy generated reliable result. Generally, endoscopic removal of hematoma with ETV, removal of hematoma through craniotomy, EVD with IVF, and EVD with early continuous LD were useful.

CONCLUSION

EVD is still crucial for the management of IVH and hydrocephalus. Despite a more reliable result from the removal of hematoma through craniotomy, a trend toward endoscopic approach was observed due to a less invasive profile.

Postoperative hydrocephalus is a high-risk lethal factor for patients with low-grade optic pathway glioma

OBJECTIVES

To explore the prognostic factors of patients with low-grade optic pathway glioma (OPG) and the optimal treatment to reduce the incidence of postoperative hydrocephalus.

PATIENTS AND METHODS

This single-center study retrospectively analyzed data from 66 patients with OPGs who underwent surgery. The patients were followed, and overall survival (OS) and progression-free survival (PFS) were determined. The effects of different treatments on the hydrocephalus of patients were compared.

RESULTS

Postoperative hydrocephalus was identified as a factor to increase the risk of mortality by 1.99-fold (p = .028). And, 5-year survival rate was significantly lower among patients with postoperative hydrocephalus (p = .027). The main factors leading to preoperative hydrocephalus in patients are large tumor volume and invasion into the third ventricle. Gross total resections (GTR) could reduce the risk of long-term hydrocephalus (p = .046). Age younger than 4 years (p = .046) and tumor invasion range/classification (p = .029) are the main factors to reduce the five-year survival rate. Postoperative radiotherapy (RT) and chemotherapy (CT) had no significant effects on OS. Extraventricular drainage (EVD) was not associated with perioperative infection (p = .798 > .05) and bleeding (p = .09 > .05). Compared with 2 stage surgery (external ventricular drainage or ventriculoperitoneal shunt (VPS) was first placed, followed by tumor resection), 1 stage surgery (direct resection of tumor) had no complication increase.

CONCLUSIONS

Postoperative hydrocephalus is mostly obstructive hydrocephalus, and it is an important factor that reduces the OS of patients with low-grade OPGs. Surgery to remove the tumor to the greatest extent improves cerebrospinal fluid circulation is effective at reducing the incidence postoperative hydrocephalus. For patients whose ventricles are still dilated after surgery, in addition to considering poor ventricular compliance, they need to be aware of the persistence and progression of hydrocephalus.

Paediatric hydrocephalus

Hydrocephalus is classically considered as a failure of cerebrospinal fluid (CSF) homeostasis that results in the active expansion of the cerebral ventricles. Infants with hydrocephalus can present with progressive increases in head circumference whereas older children often present with signs and symptoms of elevated intracranial pressure. Congenital hydrocephalus is present at or near birth and some cases have been linked to gene mutations that disrupt brain morphogenesis and alter the biomechanics of the CSF-brain interface. Acquired hydrocephalus can develop at any time after birth, is often caused by central nervous system infection or haemorrhage and has been associated with blockage of CSF pathways and inflammation-dependent dysregulation of CSF secretion and clearance. Treatments for hydrocephalus mainly include surgical CSF shunting or endoscopic third ventriculostomy with or without choroid plexus cauterization. In utero treatment of fetal hydrocephalus is possible via surgical closure of associated neural tube defects. Long-term outcomes for children with hydrocephalus vary widely and depend on intrinsic (genetic) and extrinsic factors. Advances in genomics, brain imaging and other technologies are beginning to refine the definition of hydrocephalus, increase precision of prognostication and identify nonsurgical treatment strategies.

Lumboperitoneal shunt and ventriculoperitoneal shunt for chronic hydrocephalus after aneurysmal subarachnoid hemorrhage: a comparison

Objective

Chronic hydrocephalus after aneurysmal subarachnoid hemorrhage (aSAH) results in poor neurological outcomes and cognitive deficits. Currently, the main treatments for chronic hydrocephalus include ventriculoperitoneal shunt (VPS) and lumboperitoneal shunt (LPS); however, the optimal treatment for chronic hydrocephalus after aSAH remains controversial.

Method

The records of 82 patients were retrospectively analyzed, and the patients were divided into VPS and LPS groups based on surgical methods. The efficacy, shunt successful rate and complications were compared. The assessments of treatment efficacy included the Evans index score (EIS), Keifer's hydrocephalus score (KHS), Mini-Mental State Examination (MMSE) score and functional independence measure (FIM). Patients were followed up for three months to observe the postoperative curative effects and complications.

Results

The rate of shunt obstruction was significantly higher in the LPS group than that in the VPS group (p < 0.05), and the shunt successful rate was significantly higher in the VPS group than that in the LPS group (p < 0.05). The total rate of complications was 24.4% for LPS and 39% for VPS. The improvements in EIS, KHS, MMSE, and FIM within each group after the shunt were significantly different compared to those before shunt (p < 0.05). Compared to those in the LPS group, the improvements in EIS, KHS, MMSE, and FIM were significantly different in the VPS group after shunt (p < 0.05).

Conclusion

Compared with LPS, VPS in the treatment for chronic hydrocephalus after aSAH had greater therapeutic efficacy, as indicated by improved radiological outcomes, improved shunt successful rate, improved clinical outcomes, and improved quality of life. Therefore, we believe that VPS is the preferred treatment option for chronic hydrocephalus after aSAH, while LPS should only be used as an alternative to VPS.

Aquaporin 4 Mediates the Effect of Iron Overload on Hydrocephalus After Intraventricular Hemorrhage

BACKGROUND

Iron overload plays an important role in hydrocephalus development following intraventricular hemorrhage (IVH). Aquaporin 4 (AQP4) participates in the balance of cerebrospinal fluid secretion and absorption. The current study investigated the role of AQP4 in the formation of hydrocephalus caused by iron overload after IVH.

METHODS

There were three parts to this study. First, Sprague-Dawley rats received an intraventricular injection of 100 µl autologous blood or saline control. Second, rats had IVH and were treated with deferoxamine (DFX), an iron chelator, or vehicle. Third, rats had IVH and were treated with 2-(nicotinamide)-1,3,4-thiadiazole (TGN-020), a specific AQP4 inhibitor, or vehicle. Rats underwent T2-weighted and T2* gradient-echo magnetic resonance imaging to assess lateral ventricular volume and intraventricular iron deposition at 7, 14, and 28 days after intraventricular injection and were then euthanized. Real-time quantitative polymerase chain reaction, western blot analysis, and immunofluorescence analyses were conducted on the rat brains to evaluate the expression of AQP4 at different time points. Hematoxylin and eosin-stained brain sections were obtained to assess the ventricular wall damage on day 28.

RESULTS

Intraventricular injection of autologous blood caused a significant ventricular dilatation, iron deposition, and ventricular wall damage. There was increased AQP4 mRNA and protein expression in the periventricular tissue in IVH rats through day 7 to day 28. The DFX treatment group had a lower lateral ventricular volume and less intraventricular iron deposition and ventricular wall damage than the vehicle-treated group after IVH. The expression of AQP4 protein in periventricular tissue was also inhibited by DFX on days 14 and 28 after IVH. The use of TGN-020 attenuated hydrocephalus development after IVH and inhibited the expression of AQP4 protein in the periventricular tissue between day 14 and day 28 without a significant effect on intraventricular iron deposition or ventricular wall damage.

CONCLUSIONS

AQP4 located in the periventricular area mediated the effect of iron overload on hydrocephalus after IVH.

Pilot study on high-resolution radiological methods for the analysis of cerebrospinal fluid (CSF) shunt valves

OBJECTIVES

Despite their life-saving capabilities, cerebrospinal fluid (CSF) shunts exhibit high failure rates, with a large fraction of failures attributed to the regulating valve. Due to a lack of methods for the detailed analysis of valve malfunctions, failure mechanisms are not well understood, and valves often have to be surgically explanted on the mere suspicion of malfunction. The presented pilot study aims to demonstrate radiological methods for comprehensive analysis of CSF shunt valves, considering both the potential for failure analysis in design optimization, and for future clinical in-vivo application to reduce the number of required shunt revision surgeries. The proposed method could also be utilized to develop and support in situ repair methods (e.g. by lysis or ultrasound) of malfunctioning CSF shunt valves.

MATERIALS AND METHODS

The primary methods described are contrast-enhanced radiographic time series of CSF shunt valves, taken in a favorable projection geometry at low radiation dose, and the machine-learning-based diagnosis of CSF shunt valve obstructions. Complimentarily, we investigate CT-based methods capable of providing accurate ground truth for the training of such diagnostic tools. Using simulated test and training data, the performance of the machine-learning diagnostics in identifying and localizing obstructions within a shunt valve is evaluated regarding per-pixel sensitivity and specificity, the Dice similarity coefficient, and the false positive rate in the case of obstruction free test samples.

RESULTS

Contrast enhanced subtraction radiography allows high-resolution, time-resolved, low-dose analysis of fluid transport in CSF shunt valves. Complementarily, photon-counting micro-CT allows to investigate valve obstruction mechanisms in detail, and to generate valid ground truth for machine learning-based diagnostics. Machine-learning-based detection of valve obstructions in simulated radiographies shows promising results, with a per-pixel sensitivity >70%, per-pixel specificity >90%, a median Dice coefficient >0.8 and <10% false positives at a detection threshold of 0.5.

CONCLUSIONS

This ex-vivo study demonstrates obstruction detection in cerebro-spinal fluid shunt valves, combining radiological methods with machine learning under conditions compatible to future in-vivo application. Results indicate that high-resolution contrast-enhanced subtraction radiography, possibly including time-series data, combined with machine-learning image analysis, has the potential to strongly improve the diagnostics of CSF shunt valve failures. The presented method is in principle suitable for in-vivo application, considering both measurement geometry and radiological dose. Further research is needed to validate these results on real-world data and to refine the employed methods. In combination, the presented methods enable comprehensive analysis of valve failure mechanisms, paving the way for improved product development and clinical diagnostics of CSF shunt valves.

Subdural Hygroma After Management of Ruptured Intracranial Aneurysms: Incidence, Associated Factors, Clinical Course, and Management Options

OBJECTIVE

To evaluate the incidence, associated factors, clinical course, and management options of subdural hygroma in patients treated for aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

From January 2013 until June 2022, 336 consecutive patients with aSAH underwent treatment in our center. No one patient was excluded from the study cohort. Computed tomography (CT) examinations were performed at admission, immediately after surgery and on the first postoperative day, and subsequently in case of any neurologic deterioration or, at least, once per week until discharge from the hospital. Thereafter, CT examinations were at the discretion of specialists in the rehabilitation facility, referring physicians, or neurosurgeons at the outpatient clinic.

RESULTS

The length of radiologic follow-up starting from CT at admission ranged from 1 to 3286 days (mean, 673 ± 895 days; median, 150 days). Subdural hygromas developed in 84 patients (25%). An average interval until this imaging finding from the initial CT examination was 25 ± 55 days (median, 8 days; range, 0-362 days). Evaluation in the multivariate model showed that patient age ≥72 years (P < 0.0001), cerebrospinal fluid (CSF) shunting (P < 0.0001), and microsurgical clipping of ruptured intracranial aneurysm (RIA; P < 0.0001) are independently associated with the development of subdural hygroma. In 54 of 84 cases (64%), subdural hygromas required observation only. Increase of the lesion size with (5 cases) or without (10 cases) appearance of midline shift was associated with patient age <72 years (P = 0.0398), decompressive craniotomy (P = 0.0192), and CSF shunting (P = 0.0009), whereas evaluation of these factors in the multivariate model confirmed independent association of only CSF shunting (P = 0.0003). Active management of subdural hygromas included adjustment of the shunt programmable valve opening pressure, cranioplasty, external subdural drainage, or their combination. Overall, during follow-up (mean, 531 ± 824 days; median, 119 days; range, 2-3285 days) after the start of observation or applied treatment, subdural hygromas showed either decrease (50 cases) or stabilization (34 cases) of their sizes, and no one lesion showed progression again.

CONCLUSIONS

The clinical course of subdural hygromas in patients treated for aSAH is generally favorable, but occasionally these lesions show progressive enlargement with or without the appearance of midline shift, which requires active management.

Dual function of the choroid plexus: Cerebrospinal fluid production and control of brain ion homeostasis

The choroid plexus is a small monolayered epithelium located in the brain ventricles and serves to secrete the cerebrospinal fluid (CSF) that envelops the brain and fills the central ventricles. The CSF secretion is sustained with a concerted effort of a range of membrane transporters located in a polarized fashion in this tissue. Prominent amongst these are the Na+/K+-ATPase, the Na+,K+,2Cl- cotransporter (NKCC1), and several HCO3- transporters, which together support the net transepithelial transport of the major electrolytes, Na+ and Cl-, and thus drive the CSF secretion. The choroid plexus, in addition, serves an important role in keeping the CSF K+ concentration at a level compatible with normal brain function. The choroid plexus Na+/K+-ATPase represents a key factor in the barrier-mediated control of the CSF K+ homeostasis, as it increases its K+ uptake activity when faced with elevated extracellular K+ ([K+]o). In certain developmental or pathological conditions, the NKCC1 may revert its net transport direction to contribute to CSF K+ homeostasis. The choroid plexus ion transport machinery thus serves dual, yet interconnected, functions with its contribution to electrolyte and fluid secretion in combination with its control of brain K+ levels.

Ventriculosubgaleal shunts in the management of neonatal post-haemorrhagic hydrocephalus: technical note

INTRODUCTION

Germinal matrix / intraventricular haemorrhage (GMIVH) remains a significant complication of prematurity. The more severe grades are associated with parenchymal haemorrhagic infarction (PHI) and hydrocephalus. A temporising procedure is usually the first line in management of neonatal post-haemorrhagic hydrocephalus (nPHH) as the risk of failure of a permanent cerebrospinal fluid (CSF) diversion is higher in the early stage. Our choice of temporising procedure is a ventriculosubgaleal shunt (VSGS). In this technical note, we describe a modification in technique whereby the pocket of the VSGS is fashioned away from the surgical wound. This resulted in lower CSF leak and subsequent infection rates in our centre.

METHODS

We conducted a retrospective analysis of all patients who underwent insertion of a VSGS between September 2014 and February 2023.

RESULTS

Twenty children were included in our study with a mean gestational age of 31 weeks + 4 days. Post-operatively, 10% of patients did not need a tap, and 10%, 20%, 15%, 25% and 20% respectively had 1, 2, 3, 4 and 5 taps. Two patients experienced CSF leak from their wounds. In both these patients, the pocket was deemed too close to the wound. None of the patients without suspected pre-existing CNS infection at the time of insertion of VSGS had a subsequent VSGS-related infection. VSGS conversion to permanent ventriculoperitoneal shunts (VPS) was required in 15 (75%) of the patients with an average interval duration of 72 days. On reviewing the literature, the infection rate following VSGS is quoted up to 13.5%. In our own centre, 13 patients had undergone VSGS insertion between 2005 and 2013 with a 30.8% infection rate which seemed related to increased leak rates.

CONCLUSION

Our modified surgical approach seems to be effective in reducing the risk of infection, which we postulate is a direct result of reduction in the risk of leak from the surgical wound.

CSF hypersecretion versus impaired CSF absorption in posthemorrhagic hydrocephalus: a systematic review

BACKGROUND

The molecular mechanisms underlying development of posthemorrhagic hydrocephalus (PHH) remain elusive. The aim of this systematic review was to evaluate existing literature on increased CSF secretion and impaired CSF absorption as pathogenic contributors to CSF accumulation in neonatal and adult PHH.

METHODS

The systematic review was conducted in accordance with the PRISMA guidelines. Relevant studies published before March 11th, 2023, were identified from PubMed and reference lists. Studies were screened for eligibility using predefined inclusion and exclusion criteria. Data from eligible studies were extracted and potential sources of bias were evaluated.

RESULTS

Nineteen studies quantified CSF production rates and/or CSF absorption capacity in human patients with PHH or animals with experimentally induced PHH. Increased CSF production was reported as early as 24 h and as late as 28 days post ictus in six out of eight studies quantifying CSF production rates in animals with experimentally induced PHH. Impaired CSF absorption was reported in all four studies quantifying CSF absorption capacity in human patients with PHH and in seven out of nine studies quantifying CSF absorption capacity in animals with experimentally induced PHH. Impaired CSF absorption was reported as early as 30 min and as late as 10 months post ictus.

CONCLUSIONS

The pathological CSF accumulation in PHH likely arises from a combination of increased CSF secretion and impaired CSF absorption, which may manifest at different time scales following a hemorrhagic event. Emergent evidence on increased CSF secretion by the choroid plexus may herald a paradigm shift in our understanding of PHH.

Predictive value of spinal CSF volume in the preoperative assessment of patients with idiopathic normal-pressure hydrocephalus

Introduction

The pathophysiology, diagnosis, and management of idiopathic normal pressure hydrocephalus (iNPH) remain unclear. Although some prognostic tests recommended in iNPH guidelines should have high sensitivity and high predictive value, there is often no positive clinical response to surgical treatment.

Materials and methods

In our study, 19 patients with clinical and neuroradiological signs of iNPH were selected for preoperative evaluation and possible further surgical treatment according to the guidelines. MR volumetry of the intracranial and spinal space was performed. Patients were exposed to prolonged external lumbar drainage in excess of 10 ml per hour during 3 days. Clinical response to lumbar drainage was assessed by a walk test and a mini-mental test.

Results

Twelve of 19 patients showed a positive clinical response and underwent a shunting procedure. Volumetric values of intracranial space content in responders and non-responders showed no statistically significant difference. Total CSF volume (sum of cranial and spinal CSF volumes) was higher than previously published. No correlation was found between spinal canal length, CSF pressure, and CSF spinal volume. The results show that there is a significantly higher CSF volume in the spinal space in the responder group (n = 12) (120.5 ± 14.9 ml) compared with the non-responder group (103.1 ± 27.4 ml; n = 7).

Discussion

This study demonstrates for the first time that CSF volume in the spinal space may have predictive value in the preoperative assessment of iNPH patients. The results suggest that patients with increased spinal CSF volume have decreased compliance. Additional prospective randomized clinical trials are needed to confirm our results.

Transfontanelle photoacoustic imaging of intraventricular brain hemorrhages in live sheep

Intraventricular (IVH) and periventricular (PVH) hemorrhages in preterm neonates are common because the periventricular blood vessels are still developing up to 36 weeks and are fragile. Currently, transfontanelle ultrasound (US) imaging is utilized for screening for IVH and PVH, largely through the anterior fontanelle. However for mild hemorrhages, inconclusive diagnoses are common, leading to failure to detect IVH/PVH or, when other clinical symptoms are present, use of second stage neuroimaging modalities requiring transport of vulnerable patients. Yet even mild IVH/PVH increases the risk of moderate-severe neurodevelopmental impairment. Here, we demonstrate the capability of transfontanelle photoacoustic imaging (TFPAI) to detect IVH and PVH in-vivo in a large animal model. TFPAI was able to detect IVH/PVH as small as 0.3 mL in volume in the brain (p < 0.05). By contrast, US was able to detect hemorrhages as small as 0.5 mL. These preliminary results suggest TFPAI could be translated into a portable bedside imaging probe for improved diagnosis of clinically relevant brain hemorrhages in neonates.

Distinct Cerebrospinal Fluid Lipid Signature in Patients with Subarachnoid Hemorrhage-Induced Hydrocephalus

Patients with subarachnoid hemorrhage (SAH) may develop posthemorrhagic hydrocephalus (PHH), which is treated with surgical cerebrospinal fluid (CSF) diversion. This diversion is associated with risk of infection and shunt failure. Biomarkers for PHH etiology, CSF dynamics disturbances, and potentially subsequent shunt dependency are therefore in demand. With the recent demonstration of lipid-mediated CSF hypersecretion contributing to PHH, exploration of the CSF lipid signature in relation to brain pathology is of interest. Despite being a relatively new addition to the omic's landscape, lipidomics are increasingly recognized as a tool for biomarker identification, as they provide a comprehensive overview of lipid profiles in biological systems. We here employ an untargeted mass spectroscopy-based platform and reveal the complete lipid profile of cisternal CSF from healthy control subjects and demonstrate its bimodal fluctuation with age. Various classes of lipids, in addition to select individual lipids, were elevated in the ventricular CSF obtained from patients with SAH during placement of an external ventricular drain. The lipidomic signature of the CSF in the patients with SAH suggests dysregulation of the lipids in the CSF in this patient group. Our data thereby reveal possible biomarkers present in a brain pathology with a hemorrhagic event, some of which could be potential future biomarkers for hypersecretion contributing to ventriculomegaly and thus pharmacological targets for pathologies involving disturbed CSF dynamics.

Intraventricular hemorrhage in term infants: a single institutional experience between 2016 and 2020

PURPOSE

Intraventricular hemorrhage (IVH) of prematurity is a known complication of preterm birth. Intraventricular hemorrhage in term infants is much less commonly encountered. To address the lack of information in the current literature concerning this demographic, we offer demographic and image findings that demonstrate etiology and predict the need for permanent cerebrospinal fluid (CSF) diversion.

METHODS

A prospectively maintained database was queried for all patients with intraventricular hemorrhage from 2016 to 2020 treated at our institution. Demographic data and etiology were collected, along with need for and timing of surgical intervention.

RESULTS

A total of 150 IVH patients were identified. Of these patients, 138 were excluded due to prematurity. Twelve patients were born at term with IVH. All patients were followed for at least 8 months. Seven patients (58.3%) underwent ventriculoperitoneal (VP) shunt placement, performed between 4 days and 4 months of age. Superficial siderosis detected by MRI during in-patient stay or follow-up showed a sensitivity of 100% and specificity of 60% for the future development of post-hemorrhagic hydrocephalus (PHH) (p < 0.05). All full-term infants who developed PHH (n = 7, 58.3%) obtained a VP shunt.

CONCLUSION

IVH in term infants occurs infrequently when compared to IVH of prematurity. Etiology of IVH in term infants remains difficult to ascertain, but the majority of patients did demonstrate risk factors. The presence of superficial siderosis on MRI significantly predicted the development of PHH and eventual need for CSF diversion.

Clinical outcome and prognostic factors of patients with non-traumatic angiography-negative subarachnoid hemorrhage

Purpose

The cause of spontaneous subarachnoid hemorrhage (SAH) is unknown in 10% of cases. The aim of this study was to demonstrate the characteristics of patients with angiography-negative subarachnoid hemorrhage (anSAH) and to analyze factors influencing the clinical outcome in patients suffering from anSAH.

Methods

A retrospective cohort of 75 patients with anSAH [26 perimesencephalic (pmSAH) and 49 non-perimesencephalic SAH (npmSAH)] admitted between January 2016 and June 2022 was included. We analyzed demographic, clinical data and 6-month functional outcomes. Enter regression analysis was performed to identify factors associated with outcomes.

Results

Unfavorable outcome was achieved in 10 of 75 patients (13.3%). Unfavorable outcome was associated with senior adults (p = 0.008), Hijdra cistern score (HCS) elevation (p = 0.015), long-time lumbar cistern continuous drainage (LCFD; p = 0.029) and hydrocephalus (p = 0.046). The only significant risk factor for unfavorable outcome after npmSAH was the HCS (OR 1.213 (95%CI 1.007-1.462), p = 0.042).

Conclusion

Our study provides valuable information on both SAH patterns and functional outcome in patients suffering from anSAH and should be taken into consideration during management of these patients.

Posthemorrhagic Hydrocephalus in Patients with Subarachnoid Hemorrhage Occurs Independently of CSF Osmolality

The molecular mechanisms underlying the development of posthemorrhagic hydrocephalus (PHH) remain incompletely understood. As the disease pathogenesis often cannot be attributed to visible cerebrospinal fluid (CSF) drainage obstructions, we here aimed to elucidate whether elevated CSF osmolality following subarachnoid hemorrhage (SAH) could potentiate the formation of ventricular fluid, and thereby contribute to the pathological CSF accumulation observed in PHH. The CSF osmolality was determined in 32 patients with acute SAH after external ventricular drainage (EVD) placement and again upon EVD removal and compared with the CSF osmolality from 14 healthy control subjects undergoing vascular clipping of an unruptured aneurism. However, we found no evidence of elevated CSF osmolality or electrolyte concentration in patients with SAH when compared to that of healthy control subjects. We detected no difference in CSF osmolality and electrolyte content in patients with successful EVD weaning versus those that were shunted due to PHH. Taken together, elevated CSF osmolality does not appear to underlie the development of PHH following SAH. The pathological CSF accumulation observed in this patient group must thus instead be attributed to other pathological alterations associated with the abnormal presence of blood within the CSF compartments following SAH.

Therapeutic strategies to recover ependymal barrier after inflammatory damage: relevance for recovering neurogenesis during development

The epithelium covering the surfaces of the cerebral ventricular system is known as the ependyma, and is essential for maintaining the physical and functional integrity of the central nervous system. Additionally, the ependyma plays an essential role in neurogenesis, neuroinflammatory modulation and neurodegenerative diseases. Ependyma barrier is severely affected by perinatal hemorrhages and infections that cross the blood brain barrier. The recovery and regeneration of ependyma after damage are key to stabilizing neuroinflammatory and neurodegenerative processes that are critical during early postnatal ages. Unfortunately, there are no effective therapies to regenerate this tissue in human patients. Here, the roles of the ependymal barrier in the context of neurogenesis and homeostasis are reviewed, and future research lines for development of actual therapeutic strategies are discussed.

The value of ventricular measurements in the prediction of shunt dependency after aneurysmal subarachnoid hemorrhage

OBJECTIVE

Chronic hydrocephalus requiring shunt placement is a common complication of aneurysmal subarachnoid hemorrhage (SAH). Different risk factors and prediction scores for post-SAH shunt dependency have been evaluated so far. We analyzed the value of ventricle measurements for prediction of the need for shunt placement in SAH patients.

METHODS

Eligible SAH cases treated between 01/2003 and 06/2016 were included. Initial computed tomography scans were reviewed to measure ventricle indices (bifrontal, bicaudate, Evans', ventricular, Huckman's, and third ventricle ratio). Previously introduced CHESS and SDASH scores for shunt dependency were calculated. Receiver operating characteristic analyses were performed for diagnostic accuracy of the ventricle indices and to identify the clinically relevant cut-offs.

RESULTS

Shunt placement followed in 221 (36.5%) of 606 patients. In univariate analyses, all ventricular indices were associated with shunting (all: p<0.0001). The area under the curve (AUC) ranged between 0.622 and 0.662. In multivariate analyses, only Huckman's index was associated with shunt dependency (cut-off at ≥6.0cm, p<0.0001) independent of the CHESS score as baseline prediction model. A combined score (0-10 points) containing the CHESS score components (0-8 points) and Huckman's index (+2 points) showed better diagnostic accuracy (AUC=0.751) than the CHESS (AUC=0.713) and SDASH (AUC=0.693) scores and the highest overall model quality (0.71 vs. 0.65 and 0.67), respectively.

CONCLUSIONS

Ventricle measurements are feasible for early prediction of shunt placement after SAH. The combined prediction model containing the CHESS score and Huckman's index showed remarkable diagnostic accuracy regarding identification of SAH individuals requiring shunt placement. External validation of the presented combined CHESS-Huckman score is mandatory.

Timing of operation for poor-grade aneurysmal subarachnoid hemorrhage: Relationship with delayed cerebral ischemia and poor prognosis

AIMS

To assess differences in the clinical prognosis between different treatment timings in poor-grade (Hunt and Hess grade 4-5) aneurysmal subarachnoid hemorrhage patients.

METHODS

The treated 127 poor-grade aneurysmal subarachnoid hemorrhage patients were divided into three groups: early treatment within 2 days, treatment on days 3 to 10, and treatment for more than 10 days after the hemorrhage. Odd ratios with a 95% confidence interval were calculated in logistic regression for different timing strategies regarding delayed cerebral ischemia and poor prognosis at 3 months. Subgroup analyses were conducted to determine whether the different timing strategies affect the prognosis.

RESULTS

Patients who received the treatment on days 3 to 10 were prone to develop delayed cerebral ischemia and poor prognosis at 3 months. Postponing treatment in patients older than 55 years or diagnosed with an intraventricular hematoma on the initial computed tomography scan may lead to poor prognosis, with the early intervention group as a reference.

CONCLUSIONS

Early intervention in poor-grade aneurysmal subarachnoid hemorrhage is suggested to be implemented. The treatment on 3 to 10 days harbored the highest risk of poor prognosis; patients might benefit more from early intervention, especially for ones older than 55 years or diagnosed with an intraventricular hematoma.

Application of brain ultrasound in premature infants with brain injury

Brain injury is the main factor affecting the development and prognosis of the nervous system in premature infants. Early diagnosis and treatment are of great significance in reducing mortality and disability and improving the prognosis of premature infants. Craniocerebral ultrasound has become an important medical imaging method for evaluating the brain structure of premature infants due to its advantages of being non-invasive, cheap, simple, and bedside dynamic monitoring since it was applied to neonatal clinical practice. This article reviews the application of brain ultrasound to common brain injuries in premature infants.

The Burden and In-Hospital Mortality of Stroke Admissions at a Tertiary Level Hospital in Namibia: A Retrospective Cohort Study

Background

Despite stroke being a leading cause of morbidity and mortality globally, there is a dearth of information on the burden and outcomes of stroke in sub-Saharan Africa and Namibia in particular.

Methods

A hospital-based, retrospective cohort study was conducted to analyse non-electronic medical records of all consecutive stroke patients who were admitted to one of the highest tertiary-level hospitals in Namibia for 12 months (2019-2020). The primary outcome of the study was to establish the in-hospital mortality, stroke subtypes, and associated complications.

Results

In total, 220 patients were included in the study, their mean age was 53 (SD13.8) years, and 55.5% were males. 61.0% had an ischaemic stroke (IS), and 39.0% had a haemorrhagic stroke (HS). The mean age was significantly lower in patients with HS vs. IS (48.2 ± 12.2 vs. 56.1 ± 13.3, p < 0.001). Of the IS patients, the majority (29.0%) had total anterior circulation infarct (TACI), while in the HS group, 34.0% had basal ganglia haemorrhage with or without intraventricular extension. Hypertension (p = 0.015), dyslipidaemia (p = 0.001), alcohol consumption (p = 0.022), and other cardiovascular diseases (p = 0.007) were more prevalent in patients with IS compared to those with HS. The prevalence rate of intravenous thrombolysis was 2.2% in IS and use of intravenous antihypertensives in 25.9% of patients with HS than IS. The in-hospital mortality was 26.4% with complications such as raised ICP, aspiration pneumonia, hydrocephalus, and sepsis significantly high in those that died. Aspiration pneumonia (OR 2.79, 95% CI 1.63-4.76, p < 0.001) and increased ICP (OR 0.30, 95% CI 0.16-057, p < 0.001) were independent predictors of in-hospital mortality on the multivariate analysis.

Conclusion

Our findings showed a younger mean age for stroke and mortality rate comparable to other low- to middle-income countries (LMICs). Hypertension and alcohol consumption were the main risk factors for both stroke subtypes, while aspiration pneumonia and raised intracranial pressure predicted in-hospital mortality.

Activation of the RARα Attenuated CSF Hypersecretion to Inhibit Hydrocephalus Development via Regulating the MAFB/MSR1 Pathway

Hydrocephalus has been observed in rats with spontaneous hypertension (SHRs). It has been demonstrated that activation of the oxidative stress related protein retinoic acid receptor alpha (RARα) has neuroprotective impacts. Our investigation aims to determine the potential role and mechanism of RARα in hydrocephalus. The RARα-specific agonist (Am80) and RARα inhibitor (AGN196996) were used to investigate the role of RARα in cerebrospinal fluid (CSF) secretion in the choroid plexus of SHRs. Evaluations of CSF secretion, ventricular volume, Western blotting, and immunofluorescent staining were performed. Hydrocephalus and CSF hypersecretion were identified in SHRs but not in Wistar-Kyoto rats, occurring at the age of 7 weeks. The RARα/MAFB/MSR1 pathway was also activated in SHRs. Therapy with Am80 beginning in week 5 decreased CSF hypersecretion, hydrocephalus development, and pathological changes in choroid plexus alterations by week 7. AGN196996 abolished the effect of Am80. In conclusion, activation of the RARα attenuated CSF hypersecretion to inhibit hydrocephalus development via regulating the MAFB/MSR1 pathway. RARα may act as a possible therapeutic target for hydrocephalus.

Progress in Research on TLR4-Mediated Inflammatory Response Mechanisms in Brain Injury after Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) is one of the common clinical neurological emergencies. Its incidence accounts for about 5-9% of cerebral stroke patients. Even surviving patients often suffer from severe adverse prognoses such as hemiplegia, aphasia, cognitive dysfunction and even death. Inflammatory response plays an important role during early nerve injury in SAH. Toll-like receptors (TLRs), pattern recognition receptors, are important components of the body's innate immune system, and they are usually activated by damage-associated molecular pattern molecules. Studies have shown that with TLR 4 as an essential member of the TLRs family, the inflammatory transduction pathway mediated by it plays a vital role in brain injury after SAH. After SAH occurrence, large amounts of blood enter the subarachnoid space. This can produce massive damage-associated molecular pattern molecules that bind to TLR4, which activates inflammatory response and causes early brain injury, thus resulting in serious adverse prognoses. In this paper, the process in research on TLR4-mediated inflammatory response mechanism in brain injury after SAH was reviewed to provide a new thought for clinical treatment.

Multiple Machine Learning Approaches for Morphometric Parameters in Prediction of Hydrocephalus

BACKGROUND

The diagnosis of hydrocephalus is mainly based on imaging findings. However, the significance of many imaging indicators may change, especially in some degenerative diseases, and even lead to misdiagnosis.

METHODS

This study explored the effectiveness of commonly used morphological parameters and typical radiographic findings in hydrocephalus diagnosis. The patients' imaging data were divided into three groups, including the hydrocephalus group, the symptomatic group, and the normal control group. The diagnostic validity and weight of various parameters were compared between groups by multiple machine learning methods.

RESULTS

Our results demonstrated that Evans' ratio is the most valuable diagnostic indicator compared to the hydrocephalus group and the normal control group. But frontal horns' ratio is more useful in diagnosing patients with symptoms. Meanwhile, the sign of disproportionately enlarged subarachnoid space and third ventricle enlargement could be effective diagnostic indicators in all situations.

CONCLUSION

Both morphometric parameters and radiological features were essential in diagnosing hydrocephalus, but the weights are different in different situations. The machine learning approaches can be applied to optimize the diagnosis of other diseases and consistently update the clinical diagnostic criteria.

Risk factors of postoperative hydrocephalus following decompressive craniectomy for spontaneous intracranial hemorrhages and intraventricular hemorrhage

INTRODUCTION

Hydrocephalus is a complication of spontaneous intracerebral hemorrhage; however, its predictive relationship with hydrocephalus in this patient cohort is not understood. Here, we evaluated the incidence and risk factors of hydrocephalus after craniectomy.

METHODS

Retrospectively studied data from 39 patients in the same hospital from 2016/01 to 2020/12 and analyzed risk factors for hydrocephalus. The clinical data recorded included patient age, sex, timing of surgery, initial Glasgow Coma Scale score, intracerebral hemorrhage (ICH) score, alcohol consumption, cigarette smoking, medical comorbidity, and blood data. Predictors of patient outcomes were determined using Student t test, chi-square test, and logistic regression.

RESULTS

We recruited 39 patients with cerebral herniation who underwent craniectomy for spontaneous supratentorial hemorrhage. Persistent hydrocephalus was observed in 17 patients. The development of hydrocephalus was significantly associated with the timing of operation, cigarette smoking, and alcohol consumption according to the Student t test and chi-square test. Univariate and multivariate analyses suggested that postoperative hydrocephalus was significantly associated with the timing of surgery (P = .031) and cigarette smoking (P = .041).

DISCUSSION

The incidence of hydrocephalus in patients who underwent delayed operation (more than 4 hours) was lower than that in patients who underwent an operation after less than 4 hours. nonsmoking groups also have lower incidence of hydrocephalus. Among patients who suffered from spontaneous supratentorial hemorrhage and need to receive emergent craniectomy, physicians should be reminded that postoperative hydrocephalus followed by ventriculoperitoneal shunting may be necessary in the future.

Lysophosphatidic acid as a CSF lipid in posthemorrhagic hydrocephalus that drives CSF accumulation via TRPV4-induced hyperactivation of NKCC1

BACKGROUND

A range of neurological pathologies may lead to secondary hydrocephalus. Treatment has largely been limited to surgical cerebrospinal fluid (CSF) diversion, as specific and efficient pharmacological options are lacking, partly due to the elusive molecular nature of the CSF secretion apparatus and its regulatory properties in physiology and pathophysiology.

METHODS

CSF obtained from patients with subarachnoid hemorrhage (SAH) and rats with experimentally inflicted intraventricular hemorrhage (IVH) was analyzed for lysophosphatidic acid (LPA) by alpha-LISA. We employed the in vivo rat model to determine the effect of LPA on ventricular size and brain water content, and to reveal the effect of activation and inhibition of the transient receptor potential vanilloid 4 (TRPV4) ion channel on intracranial pressure and CSF secretion rate. LPA-mediated modulation of TRPV4 was determined with electrophysiology and an ex vivo radio-isotope assay was employed to determine the effect of these modulators on choroid plexus transport.

RESULTS

Elevated levels of LPA were observed in CSF obtained from patients with subarachnoid hemorrhage (SAH) and from rats with experimentally-inflicted intraventricular hemorrhage (IVH). Intraventricular administration of LPA caused elevated brain water content and ventriculomegaly in experimental rats, via its action as an agonist of the choroidal transient receptor potential vanilloid 4 (TRPV4) channel. TRPV4 was revealed as a novel regulator of ICP in experimental rats via its ability to modulate the CSF secretion rate through its direct activation of the Na+/K+/2Cl- cotransporter (NKCC1) implicated in CSF secretion.

CONCLUSIONS

Together, our data reveal that a serum lipid present in brain pathologies with hemorrhagic events promotes CSF hypersecretion and ensuing brain water accumulation via its direct action on TRPV4 and its downstream regulation of NKCC1. TRPV4 may therefore be a promising future pharmacological target for pathologies involving brain water accumulation.

Posthemorrhagic hydrocephalus associates with elevated inflammation and CSF hypersecretion via activation of choroidal transporters

INTRODUCTION

Posthemorrhagic hydrocephalus (PHH) often develops following hemorrhagic events such as intraventricular hemorrhage (IVH) and subarachnoid hemorrhage (SAH). Treatment is limited to surgical diversion of the cerebrospinal fluid (CSF) since no efficient pharmacological therapies are available. This limitation follows from our incomplete knowledge of the molecular mechanisms underlying the ventriculomegaly characteristic of PHH. Here, we aimed to elucidate the molecular coupling between a hemorrhagic event and the subsequent PHH development, and reveal the inflammatory profile of the PHH pathogenesis.

METHODS

CSF obtained from patients with SAH was analyzed for inflammatory markers using the proximity extension assay (PEA) technique. We employed an in vivo rat model of IVH to determine ventricular size, brain water content, intracranial pressure, and CSF secretion rate, as well as for transcriptomic analysis. Ex vivo radio-isotope assays of choroid plexus transport were employed to determine the direct effect of choroidal exposure to blood and inflammatory markers, both with acutely isolated choroid plexus and after prolonged exposure obtained with viable choroid plexus kept in tissue culture conditions.

RESULTS

The rat model of IVH demonstrated PHH and associated CSF hypersecretion. The Na+/K+-ATPase activity was enhanced in choroid plexus isolated from IVH rats, but not directly stimulated by blood components. Inflammatory markers that were elevated in SAH patient CSF acted on immune receptors upregulated in IVH rat choroid plexus and caused Na+/K+/2Cl- cotransporter 1 (NKCC1) hyperactivity in ex vivo experimental conditions.

CONCLUSIONS

CSF hypersecretion may contribute to PHH development, likely due to hyperactivity of choroid plexus transporters. The hemorrhage-induced inflammation detected in CSF and in the choroid plexus tissue may represent the underlying pathology. Therapeutic targeting of such pathways may be employed in future treatment strategies towards PHH patients.

Metformin Preserves VE–Cadherin in Choroid Plexus and Attenuates Hydrocephalus via VEGF/VEGFR2/p-Src in an Intraventricular Hemorrhage Rat Model

Hydrocephalus induced by intraventricular hemorrhage (IVH) is associated with unfavorable prognosis. The increased permeability of choroid plexus and breakdown of the blood–brain barrier (BBB) was reported as a prominent mechanism of IVH-induced hydrocephalus, and vascular endothelial–cadherin (VE–cadherin) was demonstrated to be relevant. Metformin was reported to protect endothelial junction and preserve permeability widely; however, its role in hydrocephalus remains unclear. In this study, the decreased expression of VE–cadherin in the choroid plexus, accompanied with ventricle dilation, was investigated in an IVH rat model induced by intraventricular injection of autologous blood. Metformin treatment ameliorated hydrocephalus and upregulated VE–cadherin expression in choroid plexus meanwhile. We then observed that the internalization of VE–cadherin caused by the activation of vascular endothelial growth factor (VEGF) signaling after IVH was related to the occurrence of hydrocephalus, whereas it can be reversed by metformin treatment. Restraining VEGF signaling by antagonizing VEGFR2 or inhibiting Src phosphorylation increased the expression of VE–cadherin and decreased the severity of hydrocephalus after IVH. Our study demonstrated that the internalization of VE–cadherin via the activation of VEGF signaling may contribute to IVH-induced hydrocephalus, and metformin may be a potential protector via suppressing this pathway.

Prediction of adult post-hemorrhagic hydrocephalus: a risk score based on clinical data

There is lacking research on risk factors and prediction models associated with Post-hemorrhagic hydrocephalus (PHH). Thus, this present study aimed to analyze the risk factors of PHH and establish a risk-scoring system through a large-scale study. A retrospective study of 382 patients with intracranial hemorrhage assessed age, history and diagnosis, Glasgow coma score (GCS), and fever time. After univariate and logistic regression analysis, a risk scoring system was established according to independent risk factors and evaluated using the area under the curve (AUC). Of the 382 patients, 133 (34.8%) had PHH, 43 (11.3%) received surgical treatment. Factor classification showed that age > 60 years old [odds ratio (OR): 0.347, II = 5 points], GCS < 5 (OR: 0.09, IV = 10 points), GCS 6‒8 (OR = 0.232, III = 6 points), fever time > 9 (OR: 0.202, III = 7 points), fever time 5-9 (OR: 0.341, II = 5 points), CSF-TP x time > 14,4000 group (OR: 0.267, IV = 6 points), and CSF-TP x time 9,601‒14,400 group (OR: 0.502, III = 3 points) were independent risk factors. The result of the receiver operating characteristic (ROC) prediction showed that AUC = 0.790 (0.744‒0.836). Low-risk (IV-VII), moderate (VIII-X), and high-risk group (XI-XIII) incidence of PHH were 11.76%, 50.55%, and 70.00% (p < 0.001), respectively. The coincidence rates in the validation cohort were 26.00%, 74.07%, and 100.0% (p < 0.001), respectively. AUC value was 0.860 (0.780‒0.941). The predictive model was conducive to determining the occurrence of PHH and facilitating early intervention.

Diagnosis and Surgical Management of Neonatal Hydrocephalus

Neonatal hydrocephalus represents an important pathological condition with significant impact on medical care and neurocognitive development. This condition requires early recognition, appropriate medical and surgical management, and long-term surveillance by clinicians and pediatric neurosurgeons. Common etiologies of neonatal and infant hydrocephalus include intraventricular hemorrhage related to prematurity with subsequent post-hemorrhagic hydrocephalus, myelomeningocele, and obstructive hydrocephalus due to aqueductal stenosis. Clinical markers of elevated intracranial pressure include rapid increases in head circumference across percentiles, elevation and firmness of the anterior fontanelle, splitting or splaying of cranial sutures, upgaze palsy, lethargy, frequent emesis, or episodic bradycardia (unrelated to other comorbidities). Complementing these clinical markers, imaging modalities used for the diagnosis of neonatal hydrocephalus include head ultrasonography, brain magnetic resonance imaging, and head computed tomography in urgent or emergent situations. Following diagnosis, temporizing measures may be employed prior to definitive treatment and include ventricular access device or ventriculo-subgaleal shunt insertion. Definitive surgical management involves permanent cerebrospinal fluid (CSF) diversion via CSF shunt insertion, or endoscopic third ventriculostomy with or without choroid plexus cauterization. Surgical decision-making and approaches vary based on patient age, hydrocephalus etiology, neuroanatomy, imaging findings, and medical comorbidities. Indications, surgical techniques, and clinical outcomes of these procedures continue to evolve and elicit significant attention in the research environment. In this review we describe the epidemiology, pathophysiology, clinical markers, imaging findings, early management, definitive surgical management, and clinical outcomes of pediatric patients with neonatal hydrocephalus.

Single-Center Retrospective Analysis of Risk Factors for Hydrocephalus After Lateral Ventricular Tumor Resection

Objective

There is no general consensus on the placement of preoperative and intraoperative external ventricular drainage (EVD) in patients with lateral ventricular tumors (LVTs). The aim of this study was to identify the predictors of postoperative acute and persistent hydrocephalus need for postoperative cerebrospinal fluid (CSF) drainage and guide the management of postoperative EVD in patients with LVTs.

Methods

We performed a single-institution, retrospective analysis of patients who underwent resection of LVTs in our Department between January 2011 and March 2021. Patients were divided between one group that required CSF drainage and another group without the need for CSF drainage. We analyzed the two groups by univariate and multivariate analyses to identify the predictors of the requirement for postoperative CSF drainage due to symptomatic intracranial hypertension caused by hydrocephalus.

Results

A total of 97 patients met the inclusion criteria, of which 31 patients received preoperative or intraoperative EVD. Ten patients without prophylactic EVD received postoperative EVD for postoperative acute hydrocephalus. Eleven patients received postoperative ventriculoperitoneal(VP) shunt subsequently. Logistic regression analysis showed that tumor invasion of the anterior ventricle (OR = 7.66), transependymal edema (OR = 8.76), and a large volume of postoperative intraventricular hemorrhage (IVH) (OR = 6.51) were independent risk factors for postoperative acute hydrocephalus. Perilesional edema (OR = 33.95) was an independent risk factor for postoperative VP shunt due to persistent hydrocephalus.

Conclusion

Postoperative hydrocephalus is a common complication in patients with LVTs. These findings might help to determine whether to conduct earlier interventions.

A new perspective on cerebrospinal fluid dynamics after subarachnoid hemorrhage: From normal physiology to pathophysiological changes

Knowledge about the dynamic metabolism and function of cerebrospinal fluid (CSF) physiology has rapidly progressed in recent decades. It has traditionally been suggested that CSF is produced by the choroid plexus and drains to the arachnoid villi. However, recent findings have revealed that the brain parenchyma produces a large portion of CSF and drains through the perivascular glymphatic system and meningeal lymphatic vessels into the blood. The primary function of CSF is not limited to maintaining physiological CNS homeostasis but also participates in clearing waste products resulting from neurodegenerative diseases and acute brain injury. Aneurysmal subarachnoid hemorrhage (SAH), a disastrous subtype of acute brain injury, is associated with high mortality and morbidity. Post-SAH complications contribute to the poor outcomes associated with SAH. Recently, abnormal CSF flow was suggested to play an essential role in the post-SAH pathophysiological changes, such as increased intracerebral pressure, brain edema formation, hydrocephalus, and delayed blood clearance. An in-depth understanding of CSF dynamics in post-SAH events would shed light on potential development of SAH treatment options. This review summarizes and updates the latest physiological characteristics of CSF dynamics and discusses potential pathophysiological changes and therapeutic targets after SAH.

Risk Factor of Posthemorrhagic Hydrocephalus: Cerebrospinal Fluid Total Protein

Objective

Cerebrospinal fluid total protein (CSF-TP) levels in adults with posthemorrhagic hydrocephalus (PHH) are poorly studied. The objective of this study was to explore the characteristics of CSF-TP levels in patients with PHH.

Methods

The clinical data of 156 patients with hemorrhagic brain disease were retrospectively studied and divided into PHH and NPHH groups. Single-factor and multi-factor analyses were performed, and the key role of CSF-TP was evaluated using linear analysis.

Results

Among the 156 patients, 85 (54.5%) had PHH and 34 (21.8%) underwent surgeries. Hypertension (p = 0.017), days [total fever time when body temperature ≥ 38.5°C (p = 0.04)], Glasgow Coma Scale (GCS) score (p < 0.001), and time (from the onset of the disease to the obtainment of CSF-TP after lumbar puncture (p < 0.001) were important factors for PHH. Logistic regression analysis revealed that GCS score < 8 [odds ratio (OR) = 2.943 (1.421–6.097), p = 0.004] and CSF-TP × time ≥ 9,600 [OR = 2.317 (1.108–4.849), p = 0.026] were independent risk factors for PHH. All CSF-TP values were averaged every 2 days. CSF-TP was negatively correlated with time. Linear analysis showed that CSF-TP in the PHH group was higher than that in the NPHH group at the same onset time, and that the duration of detectionin the CSF was longer.

Conclusion

Cerebrospinal fluid total protein (CSF-TP) × time ≥ 9,600 and GCS score <8 were independent risk factors for PHH. CSF-TP was higher in the PHH group than in the NPHH group.

Clinical use of a new frameless optical neuronavigation system for brain biopsies: 10 cases (2013-2020)

OBJECTIVES

The aim of the retrospective study was to describe the brain biopsy procedure using a new frameless optical neuronavigation system and to report diagnostic yield and complications associated with the procedure.

MATERIALS AND METHODS

The medical records for all dogs with forebrain lesions that underwent brain biopsy with a frameless optical neuronavigation system in a single referral hospital between 2013 and 2020 were retrospectively analysed. Following data were collected: signalment, neurological signs, diagnostic findings, number of brain biopsy samples, sampled region, complications, duration of hospitalisation, whether the samples were diagnostic and histopathological diagnoses. The device consists of a computer workstation with navigation software, an infrared camera, patient tracker and reflective instruments. The biopsy needle was equipped with reflective spheres, so the surgeon could see the position of the needle during sampling the intracranial lesion free handed through a mini-burr hole.

RESULTS

Ten dogs were included. Absolute diagnostic yield based on specific histopathological diagnosis was 73.9%. Three dogs had immune-mediated necrotizing encephalitis, two dogs showed a necrotizing leukoencephalitis and two dogs a meningoencephalitis of unknown origin. In two dogs, the brain specimen showed unspecific changes. In one dog, the samples were non-diagnostic. Seven dogs showed no neurological deterioration, one dog mild temporary ataxia and two dogs died within 36 hours post brain biopsy.

CLINICAL SIGNIFICANCE

In these 10 dogs, the frameless optical neuronavigation system employed was useful to gain diagnostic brain biopsy samples. Considering the mortality rate observed, further studies are needed to confirm the safety of this procedure and prove its actual clinical effectiveness.

Potential Risk Factors for Ventriculoperitoneal Shunt Implantation in Paediatric Patients with Posthemorrhagic Hydrocephalus of Prematurity Treated with Subcutaneous Reservoir: An Institutional Experience

BACKGROUND

Posthemorrhagic hydrocephalus of prematurity (PHHP) is a result of intraventricular hemorrhage (IVH). IVH occurs in 6 to 23% of the preterms in countries with advanced medical health care. Most of these patients will eventually require the use of ventriculoperitoneal shunt (VPS). The purpose of this study is to assess the risk factors of VPS implantation in patients with PHHP who have been treated with ventricular catheter with subcutaneous reservoir (VCSR).

METHODS

The retrospective study was conducted evaluating 35 premature patients who suffered from severe IVH. Their mean gestational age was 28 weeks. The assessment included antenatal factors such as gestational age, birth weight, and intrauterine and perinatal infection. Postparturient period factors such as the IVH grade, time between diagnosis, and VCSR implantation and body weight on VCSR implantation were also considered in the study. Postprocedural complications, such as bacterial cerebrospinal fluid (CSF) infection, sepsis, and skin lesions, were evaluated. Data were calculated with R program, version 4.04.

RESULTS

From among 35 evaluated patients, 23 (65.71%) required a VPS. Median of birth weight was 1,190 g. Infections were observed in 11 (31.43%) cases. Mean time between IVH diagnosis and VCSR implantation was 2.6 weeks. Postprocedural complications occurred in 19 (54.29%) patients. None of the evaluated factors has proven its statistical significance (p > 0.05) for being a potential risk factor for VPS implantation.

CONCLUSION

External factors seem to not affect the necessity of VPS implantation in patients after the severe IVH. Ostensibly, there seems to be no difference between the grades III and the IV of Papile's IVH scale regarding VPS implantation necessity.

A Brief Overview of the Cerebrospinal Fluid System and Its Implications for Brain and Spinal Cord Diseases

A comprehensive understanding of the cerebrospinal fluid (CSF) system is essential for our understanding of health and disease within the central nervous system (CNS). The system of CSF refers to all components involved in CSF production, movement, and absorption. In recent years, extensive research has resulted in vastly improved understanding of the CSF system in health and disease. Yet, several aspects remain to be fully clarified, notably along the spinal cord as the preponderance of research has focused on the brain. This review briefly summarizes the CSF system and its implications for CNS diseases and highlights the knowledge gaps that require further research.

Inflammatory hydrocephalus

Reparative inflammation is an important protective response that eliminates foreign organisms, damaged cells, and physical irritants. However, inappropriately triggered or sustained inflammation can respectively initiate, propagate, or prolong disease. Post-hemorrhagic (PHH) and post-infectious hydrocephalus (PIH) are the most common forms of hydrocephalus worldwide. They are treated using neurosurgical cerebrospinal fluid (CSF) diversion techniques with high complication and failure rates. Despite their distinct etiologies, clinical studies in human patients have shown PHH and PIH share similar CSF cytokine and immune cell profiles. Here, in light of recent work in model systems, we discuss the concept of "inflammatory hydrocephalus" to emphasize potential shared mechanisms and potential therapeutic vulnerabilities of these disorders. We propose that this change of emphasis could shift our thinking of PHH and PIH from a framework of life-long neurosurgical disorders to that of preventable conditions amenable to immunomodulation.

External ventricular drainage for posthemorrhagic ventricular dilatation in preterm infants: insights on efficacy and failure

OBJECTIVE

The objective of this study was to describe the clinical and neuroradiological characteristics of a cohort of preterm infants who had undergone external ventricular drain insertion as a temporary measure to treat posthemorrhagic ventricular dilatation. In addition, the authors investigated the factors predicting permanent shunt dependency.

METHODS

The authors retrospectively reviewed the medical records of a cohort of preterm infants who had undergone external ventricular drain insertion at Gaslini Children's Hospital (Genoa, Italy) between March 2012 and February 2018. They also analyzed clinical characteristics and magnetic resonance imaging data, including diffusion- and susceptibility-weighted imaging studies, which were obtained before both catheter insertion and removal.

RESULTS

Twenty-eight infants were included in the study. The mean gestational age was 28.2 ± 2.7 weeks, and the mean birth weight was 1209 ± 476 g. A permanent ventriculoperitoneal shunt was inserted in 15/28 (53.6%) infants because of the failure of external ventricular drainage as a temporary treatment option. Compared with the shunt-free group, the shunt-dependent group had a significantly lower gestational age (29.3 ± 2.3 vs 27.2 ± 2.7 weeks, p = 0.035) and tended toward a lower birth weight (p = 0.056). None of the clinical and neuroradiological characteristics significantly differed between the shunt-free and shunt-dependent groups at the time of catheter insertion. As expected, ventricular parameters as well as the intraventricular extension of intracerebral hemorrhage, as assessed using the intraventricular hemorrhage score, were reportedly higher in the shunt-dependent group than in the shunt-free group before catheter removal.

CONCLUSIONS

External ventricular drainage is a reliable first-line treatment for posthemorrhagic hydrocephalus. However, predicting its efficacy as a unique treatment remains challenging. A lower gestational age is associated with a higher risk of posthemorrhagic hydrocephalus progression, suggesting that the more undeveloped the mechanisms for the clearance of blood degradation products, the greater the risk of requiring permanent cerebrospinal fluid diversion, although sophisticated MRI investigations are currently unable to corroborate this hypothesis.

Non-invasive assessment of cerebrospinal fluid flow dynamics using phase-contrast magnetic resonance imaging in communicating hydrocephalus

This work aims to evaluate the changes in cerebrospinal fluid (CSF) hydrodynamics in patients diagnosed with communicating hydrocephalus. Besides, we establish the relationship between CSF flow dynamic parameters on the midbrain aqueduct and intracranial pressure (ICP). CSF hydrodynamics analysis was performed using Phase-Contrast Magnetic Resonance Imaging (PC-MRI) techniques on the midbrain aqueduct of 41 patients diagnosed with communicating hydrocephalus and 22 healthy volunteers. The correlation between CSF average flow in the midbrain aqueduct and intracranial pressure measured by Lumbar Puncture (LP) was assessed in patients with hydrocephalus. Pearson correlation coefficient was used to establish the correction between the average CSF flow of midbrain aqueduct and ICP. CSF dynamic parameters of the midbrain aqueduct in hydrocephalus patients, including peak positive velocity (7.348 cm/s), average velocity (0.623 cm/s), average flow (50.799 mm³/s), and regions of interest (ROI) area (9.978 mm²) were significantly higher than in the healthy controls (p < 0.05). This was after adjusting the age, gender, heart rate, systolic blood pressure, diastolic blood pressure, and body mass index. However, only the peak negative velocity of the midbrain aqueduct did not significantly differ between the groups (p = 0.209). A positive correlation was noted between the average flow (AF) of the midbrain aqueducts and ICP in hydrocephalus patients (y (AF) = 0.386× (ICP)-33.738, r = 0.787, p < 0.05). Reference data of CSF flow dynamic parameters was obtained through the PC-MRI in middle-aged healthy volunteers and communicating hydrocephalus patients. Although the sample size was constrained, this study has significant contributions. For instance, a significant correlation was noted between the average CSF flow of the aqueduct and ICP. This therefore provides a reference for clinicians to monitor ICP in patients with hydrocephalus.

Shunting outcomes in communicating hydrocephalus: protocol for a multicentre, open-label, randomised controlled trial

INTRODUCTION

Ventriculoperitoneal shunt (VPS) remains the most widely used methods to treat communicating hydrocephalus. More recently, lumboperitoneal shunt (LPS) has been suggested as a reasonable option in some studies. However, there is lack of high-quality studies comparing these two techniques in order to certain the benefits and harms to use one of these two methods. The purpose of the current study is to determine the effectiveness and safety of the LPS versus the VPS in patients with communicating hydrocephalus.

METHODS AND ANALYSIS

All eligible patients aged 18-90 years with communicating hydrocephalus will be recruited and then randomly allocated into LPS or VPS group in a ratio of 1:1. All patients will be analysed before shunt insertion, at the time of discharge, 1 month, 6 months, 12 months and 24 months postoperatively. The primary outcome measure is the rate of shunt failure at a 2-year follow-up term. The secondary outcomes include Keifer's Hydrocephalus Scale, National Institute of Health Stroke Scale, Glasgow Outcome Scale Extended, Evans index, safety endpoints and cost-effectiveness of hospital stay.

ETHICS AND DISSEMINATION

The study will be performed in compliance with the Declaration of Helsinki (2002) of the World Medical Association. The study was approved by Institutional Review Board of West China Hospital. All patients will be fully informed the potential benefits, potential risks and responsibilities, those who will sign the informed consents once they are included. Preliminary and final results will be published in peer-reviewed journals and presented at national and international congresses.

TRIAL REGISTRATION NUMBER

ChiCTR2100043839.

Development of an In Vitro Hemorrhagic Hydrocephalus Model for Functional Evaluation of Magnetic Microactuators Against Shunt Obstructions

OBJECTIVE

Occlusion of ventriculoperitoneal shunts placed after intraventricular hemorrhage occurs frequently. The objective of this study was to develop a hemorrhagic hydrocephalus model to assess the ability of an oscillating microactuator within the ventricular catheter (VC) to prevent shunt obstruction.

METHODS

An in vitro hydrocephalus model with extreme risk of shunt obstruction was created. Phosphate-buffered saline, blood, and thrombin were driven through ventriculoperitoneal shunts for 8 hours. Five VCs were fitted with a microactuator and compared with 5 control VCs. The microactuator was actuated by an external magnetic field for 30 minutes. Pressure within the imitation lateral ventricle was measured.

RESULTS

In the 5 control shunts, 6 obstructions developed (3 VC, 3 valve-distal catheter) compared with 1 obstruction (VC) in the 5 microactuator shunts. In the control and microactuator groups, the median volume exiting the shunts in 8 hours was 30 mL versus 256 mL. Median time to reach an intraventricular pressure of 40 mm Hg (13.8 minutes vs. >8 hours), median total time >40 mm Hg (6.2 hours vs. 0.0 hours), and median maximum pressure (192 mm Hg vs. 36 mm Hg) were significantly improved in the microactuator group (P < 0.01).

CONCLUSIONS

In addition to protecting the VC, the microactuator appeared to prevent hematoma obstructing the valve or distal catheter, resulting in a much longer duration of low intraventricular pressures. A microactuator activated by placing the patient's head in an external magnetic field could reduce shunt obstructions in hemorrhagic hydrocephalus.

Cumulative Damage: Cell Death in Posthemorrhagic Hydrocephalus of Prematurity

Globally, approximately 11% of all infants are born preterm, prior to 37 weeks’ gestation. In these high-risk neonates, encephalopathy of prematurity (EoP) is a major cause of both morbidity and mortality, especially for neonates who are born very preterm (<32 weeks gestation). EoP encompasses numerous types of preterm birth-related brain abnormalities and injuries, and can culminate in a diverse array of neurodevelopmental impairments. Of note, posthemorrhagic hydrocephalus of prematurity (PHHP) can be conceptualized as a severe manifestation of EoP. PHHP impacts the immature neonatal brain at a crucial timepoint during neurodevelopment, and can result in permanent, detrimental consequences to not only cerebrospinal fluid (CSF) dynamics, but also to white and gray matter development. In this review, the relevant literature related to the diverse mechanisms of cell death in the setting of PHHP will be thoroughly discussed. Loss of the epithelial cells of the choroid plexus, ependymal cells and their motile cilia, and cellular structures within the glymphatic system are of particular interest. Greater insights into the injuries, initiating targets, and downstream signaling pathways involved in excess cell death shed light on promising areas for therapeutic intervention. This will bolster current efforts to prevent, mitigate, and reverse the consequential brain remodeling that occurs as a result of hydrocephalus and other components of EoP.

The regulatory roles of motile cilia in CSF circulation and hydrocephalus

Background

Cerebrospinal fluid (CSF) is an ultra-filtrated colorless brain fluid that circulates within brain spaces like the ventricular cavities, subarachnoid space, and the spine. Its continuous flow serves many primary functions, including nourishment, brain protection, and waste removal.

Main body

The abnormal accumulation of CSF in brain cavities triggers severe hydrocephalus. Accumulating evidence had indicated that synchronized beats of motile cilia (cilia from multiciliated cells or the ependymal lining in brain ventricles) provide forceful pressure to generate and restrain CSF flow and maintain overall CSF circulation within brain spaces. In humans, the disorders caused by defective primary and/or motile cilia are generally referred to as ciliopathies. The key role of CSF circulation in brain development and its functioning has not been fully elucidated.

Conclusions

In this review, we briefly discuss the underlying role of motile cilia in CSF circulation and hydrocephalus. We have reviewed cilia and ciliated cells in the brain and the existing evidence for the regulatory role of functional cilia in CSF circulation in the brain. We further discuss the findings obtained for defective cilia and their potential involvement in hydrocephalus. Furthermore, this review will reinforce the idea of motile cilia as master regulators of CSF movements, brain development, and neuronal diseases.

Optimal timing and safety of the external ventricular drainage in patients with high-grade aneurysmal subarachnoid hemorrhage treated with endovascular coiling

The presented retrospective analysis has evaluated the optimal timing and safety of external ventricular drainage (EVD) for acute hydrocephalus after aneurysmal subarachnoid hemorrhage (aSAH). The study cohort comprised 102 patients, 49 of whom underwent EVD at 3-120 h (mean, 16 h) after the clinical onset of aSAH, either before (N = 27) or after (N = 22) ruptured aneurysm coiling. Among those treated with EVD, favorable and fair outcomes at discharge (modified Rankin Scale [mRS] scores 0-3) were noted in 14 (29%) and unfavorable (mRS scores 4-6) in 35 (71%). The former was more common among women (P = 0.019) and patients without chronic arterial hypertension (P = 0.028). The cut-off value for optimal timing of EVD was defined at 13 h after the onset of aSAH. Favorable and fair outcomes were more frequent after early (≤13 h; N = 30) than late (>13 h; N = 19) EVD (40% vs. 11%; P = 0.026), whereas did not differ significantly between those in whom such procedure was done before or after ruptured aneurysm coiling (19% vs. 41%; P = 0.083). In the entire study cohort, 2 patients had re-rupture of the aneurysm, and while both of them were treated with EVD, neither case of complication was directly associated with the procedure and, in fact, preceded it. In conclusion, EVD for management of acute hydrocephalus in patients with high-grade aSAH should be preferably applied within 13 h after the clinical onset of stroke, which may be considered sufficiently safe regardless whether it is performed before or after ruptured aneurysm coiling.

Inflammatory Markers in Cerebrospinal Fluid from Patients with Hydrocephalus: A Systematic Literature Review

OBJECTIVE

The aim of this systematic review was to evaluate existing literature on inflammatory markers in CSF from patients with hydrocephalus and identify potential markers capable of promoting hydrocephalus development and progression.

METHODS

Relevant studies published before December 3rd 2020 were identified from PubMed, Embase, and reference lists. Studies were screened for eligibility using the predefined inclusion and exclusion criteria. Data from eligible studies were extracted, and sources of bias were evaluated. We included articles written in English investigating inflammatory markers in CSF from patients with hydrocephalus and control subjects. The review was conducted according to the PRISMA guidelines by three independent reviewers.

RESULTS

Twenty-two studies analyzed CSF from 311 patients with idiopathic normal pressure hydrocephalus (iNPH), 178 with posthemorrhagic hydrocephalus (PHH), 151 with other hydrocephalus diagnoses, and 394 control subjects. Fifty-eight inflammatory markers were investigated. The CSF of iNPH patients had increased CSF levels of IL-6, IL-1β, and LRG compared with control subjects, whereas the CSF of PHH patients had increased levels of IL-6, IL-18, and VEGF. CSF from patients with "other hydrocephalus diagnoses" had elevated IFN-γ compared to control subjects, and VEGF was increased in congenital hydrocephalus, spina bifida, and hydrocephalus associated with tuberculous meningitis compared with controls.

CONCLUSION

IL-6, IL-1β, LRG, IL-18, VEGF, and IFN-γ are elevated in CSF from patients with hydrocephalus and may be involved in promotion of hydrocephalus development and progression. They may serve as novel disease biomarkers, and their signaling pathways may represent targets for pharmacological management of hydrocephalus.

Intraventricular Hemorrhage and White Matter Injury in Preclinical and Clinical Studies

Germinal matrix-intraventricular hemorrhage (IVH) occurs in nearly half of infants born at less than 26 weeks' gestation. Up to 50% of survivors with IVH develop cerebral palsy, cognitive deficits, behavioral disorders, posthemorrhagic ventricular dilatation, or a combination of these sequelae. After the initial bleeding and the primary brain injury, inflammation and secondary brain injury might lead to periventricular leukomalacia or diffuse white matter injury. Potential factors that are involved include microglia and astrocyte activation, degradation of blood components with release of "toxic" products, infiltration of the brain by systemic immune cells, death of neuronal and glial cells, and arrest of preoligodendrocyte maturation. In addition, impairment of the blood-brain barrier may play a major role in the pathophysiology. A wide range of animal models has been used to explore causes and mechanisms leading to IVH-induced brain injury. Preclinical studies have identified potential targets for enhancing brain repair. However, little has been elucidated about the effectiveness of potential interventions in clinical studies. A systematic review of available preclinical and clinical studies might help identify research gaps and which types of interventions may be prioritized. Future trials should report clinically robust and long-term outcomes after IVH.