Posttraumatic ventriculomegaly: hydrocephalus or atrophy? A new approach for diagnosis using CSF dynamics

Structural neuroimaging markers of normal pressure hydrocephalus versus Alzheimer's dementia and Parkinson's disease, and hydrocephalus versus atrophy in chronic TBI-a narrative review

Introduction

Normal Pressure Hydrocephalus (NPH) is a prominent type of reversible dementia that may be treated with shunt surgery, and it is crucial to differentiate it from irreversible degeneration caused by its symptomatic mimics like Alzheimer's Dementia (AD) and Parkinson's Disease (PD). Similarly, it is important to distinguish between (normal pressure) hydrocephalus and irreversible atrophy/degeneration which are among the chronic effects of Traumatic Brain Injury (cTBI), as the former may be reversed through shunt placement. The purpose of this review is to elucidate the structural imaging markers which may be foundational to the development of accurate, noninvasive, and accessible solutions to this problem.

Methods

By searching the PubMed database for keywords related to NPH, AD, PD, and cTBI, we reviewed studies that examined the (1) distinct neuroanatomical markers of degeneration in NPH versus AD and PD, and atrophy versus hydrocephalus in cTBI and (2) computational methods for their (semi-) automatic assessment on Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) scans.

Results

Structural markers of NPH and those that can distinguish it from AD have been well studied, but only a few studies have explored its structural distinction between PD. The structural implications of cTBI over time have been studied. But neuroanatomical markers that can predict shunt response in patients with either symptomatic idiopathic NPH or post-traumatic hydrocephalus have not been reliably established. MRI-based markers dominate this field of investigation as compared to CT, which is also reflected in the disproportionate number of MRI-based computational methods for their automatic assessment.

Conclusion

Along with an up-to-date literature review on the structural neurodegeneration due to NPH versus AD/PD, and hydrocephalus versus atrophy in cTBI, this article sheds light on the potential of structural imaging markers as (differential) diagnostic aids for the timely recognition of patients with reversible (normal pressure) hydrocephalus, and opportunities to develop computational tools for their objective assessment.

The Top 100 Most Cited Journal Articles on Hydrocephalus

Hydrocephalus represents a significant burden of disease, with more than 383,000 new cases annually worldwide. When the magnitude of this condition is considered, a centralized archive of pertinent literature is of great clinical value. From a neurosurgical standpoint, hydrocephalus is one of the most frequently treated conditions in the field. The focus of this study was to identify the top 100 journal articles specific to hydrocephalus using bibliometric analysis. Using the Journal of Citation Report database, 10 journals were identified. The Web of Science Core Collection was then searched using each journal name and the search term "hydrocephalus." The results were ordered by "Times Cited" and searched by the number of citations. The database contained journal articles from 1976 to 2021, and the following variables were collected for analysis: journal, article type, year of publication, and the number of citations. Journal articles were excluded if they had no relation to hydrocephalus, mostly involved basic science research, or included animal studies. Ten journals were identified using the above criteria, and a catalog of the 100 most cited publications in the hydrocephalus literature was created. Articles were arranged from highest to lowest citation number, with further classification by journal, article type, and publication year. Of the 100 articles referenced, 38 were review articles, 24 were original articles, 15 were comparative studies, 11 were clinical trials, six were multi-center studies, three were cross-sectional, and three were case reports with reviews. Articles were also sorted by study type and further stratified by etiology. If the etiology was not specified, studies were instead subcategorized by treatment type. Etiologies such as aqueductal stenosis, tumors, and other obstructive causes of hydrocephalus were classified as obstructive (n=6). Communicating (n=15) included idiopathic, normal pressure hydrocephalus, and other non-obstructive etiologies. The category "other" (n=3) was assigned to studies that included etiologies, populations, and/or treatments that did not fit into the classifications previously outlined. Through our analysis of highly cited journal articles focusing on different etiologies and the surgical or medical management of hydrocephalus, we hope to elucidate important trends. By establishing the 100 most cited hydrocephalus articles, we contribute one source, stratified for efficient referencing, to facilitate clinical care and future research on hydrocephalus.

A New Clinical Protocol for a Timely Diagnosis and Treatment of Hydrocephalus in Patients with Severe Acquired Brain Injury

BACKGROUND

Secondary hydrocephalus is a well-known complication of severe acquired brain injuries (sABIs) often diagnosed during inpatient rehabilitation. Currently, there is no gold standard for its detection. Therefore, we designed a novel clinical diagnostic protocol that integrates clinical, functional, biochemical and neuroradiological assessments to improve the accuracy of its diagnosis in patients with sABIs.

METHODS

This prospective cohort study will be conducted in a tertiary referral rehabilitation center in Italy. A historical cohort of patients will be compared with a prospective cohort undergoing the new clinical diagnostic protocol.

EXPECTED RESULTS

The expected results include an increase in the proportion of diagnosed cases, a reduced incidence of clinical complications, an increase in the rehabilitative outcomes at discharge, a significant reduction in the length of hospital stay, and useful information about the diagnostic and prognostic value of the neuroradiological characteristics.

CONCLUSION

We expect that this clinical diagnostic protocol will result in a more appropriate assessment and timely treatment of secondary hydrocephalus in patients with sABIs, with the ultimate goal of improving their prognosis. In addition, it could be adopted by other rehabilitation centers to improve hydrocephalus diagnosis and treatment, thereby reducing the length of hospital stay and accelerating recovery with benefits for both patients and hospitals.

Consideration of Kinase Inhibitors for the Treatment of Hydrocephalus

Hydrocephalus is a devastating condition characterized by excess cerebrospinal fluid (CSF) in the brain. Currently, the only effective treatment is surgical intervention, usually involving shunt placement, a procedure prone to malfunction, blockage, and infection that requires additional, often repetitive, surgeries. There are no long-term pharmaceutical treatments for hydrocephalus. To initiate an intelligent drug design, it is necessary to understand the biochemical changes underlying the pathology of this chronic condition. One potential commonality in the various forms of hydrocephalus is an imbalance in fluid–electrolyte homeostasis. The choroid plexus, a complex tissue found in the brain ventricles, is one of the most secretory tissues in the body, producing approximately 500 mL of CSF per day in an adult human. In this manuscript, two key transport proteins of the choroid plexus epithelial cells, transient receptor potential vanilloid 4 and sodium, potassium, 2 chloride co-transporter 1, will be considered. Both appear to play key roles in CSF production, and their inhibition or genetic manipulation has been shown to affect CSF volume. As with most transporters, these proteins are regulated by kinases. Therefore, specific kinase inhibitors are also potential targets for the development of pharmaceuticals to treat hydrocephalus.

[Surgical treatment of patients with skull defects and cerebrospinal fluid flow disorders after previous decompressive craniectomy]

Decompressive craniectomy (DC) is performed for refractory intracranial hypertension following severe traumatic brain injury, vascular and oncological diseases. This fact increases the number of patients with extensive and giant skull defects. Cerebrospinal fluid (CSF) flow disorders after DC are often accompanied by ventriculomegaly. However, only some patients with ventriculomegaly have hydrocephalus and require CSF bypass procedures. Differentiation of post-traumatic hydrocephalus requiring surgical treatment and atrophic dilation of ventricular system «ex vacuo» caused by brain injury is still an important issue. Skull sealing as a way to normalize CSF circulation and eliminate hydrocephalus is also an open question. Currently, there is no unified approach to patients with extensive and giant cranial defects combined with post-traumatic hydrocephalus. There is no unified algorithm for sequence of reconstructive and CSF bypass operations in these patients. Literature data on risks of infectious complications for different surgical strategies are controversial.

Sulfatide Deficiency, an Early Alzheimer's Lipidomic Signature, Causes Brain Ventricular Enlargement in the Absence of Classical Neuropathological Hallmarks

Alzheimer's disease (AD) is a neurodegenerative disease characterized by progressive memory loss and a decline in activities of daily life. Ventricular enlargement has been associated with worse performance on global cognitive tests and AD. Our previous studies demonstrated that brain sulfatides, myelin-enriched lipids, are dramatically reduced in subjects at the earliest clinically recognizable AD stages via an apolipoprotein E (APOE)-dependent and isoform-specific process. Herein, we provided pre-clinical evidence that sulfatide deficiency is causally associated with brain ventricular enlargement. Specifically, taking advantage of genetic mouse models of global and adult-onset sulfatide deficiency, we demonstrated that sulfatide losses cause ventricular enlargement without significantly affecting hippocampal or whole brain volumes using histological and magnetic resonance imaging approaches. Mild decreases in sulfatide content and mild increases in ventricular areas were also observed in human APOE4 compared to APOE2 knock-in mice. Finally, we provided Western blot and immunofluorescence evidence that aquaporin-4, the most prevalent aquaporin channel in the central nervous system (CNS) that provides fast water transportation and regulates cerebrospinal fluid in the ventricles, is significantly increased under sulfatide-deficient conditions, while other major brain aquaporins (e.g., aquaporin-1) are not altered. In short, we unraveled a novel and causal association between sulfatide deficiency and ventricular enlargement. Finally, we propose putative mechanisms by which sulfatide deficiency may induce ventricular enlargement.

Changes in computed tomography perfusion parameters and maximum contrast enhancement in patients having hydrocephalus with a ventriculoperitoneal shunt: a pilot study

BACKGROUND

Acute hydrocephalus may decrease cerebral perfusion by increasing intracranial pressure. Computed tomography perfusion (CTP) has become a significant adjunct in evaluating regional and global cerebral blood flow (CBF).

PURPOSE

To investigate the changes in cerebral perfusion parameters and maximum contrast enhancement (MCE) in patients with hydrocephalus with ventriculoperitoneal shunt (VPS).

MATERIAL AND METHODS

We performed brain CTP in 45 patients, including those with subarachnoid hemorrhage (SAH)-induced hydrocephalus with VPS (n = 14, G1), hydrocephalus (not related to SAH) with VPS (n = 11, G2), SAH-induced hydrocephalus without VPS (n = 10, G3), and hydrocephalus (not related to SAH) without VPS (n = 10, G4). We measured the cerebral perfusion in the frontal white matter (FWM), centrum semiovale, basal ganglia (BG), and eight cortical lesions of interest and compared the differences in CTP parameters among the groups.

RESULTS

Between the four groups, cerebral blood volume and MCE in the left FWM and CBF in the right FWM increased significantly in G1 and G2 who underwent VP shunt compared to G3 and G4, whereas perfusion significantly reduced in G3 and G4 who did not undergo VP shunt compared to G1 and G2. MCE in the left BG significantly increased in G2 and decreased in G3 and G4. SAH-induced hydrocephalus showed a lower perfusion than hydrocephalus (not related to SAH) in FWM.

CONCLUSIONS

Perfusion changes in patients with hydrocephalus after VP shunt were seen in the FWM and BG, which appears to be the result of the hydrocephalus reducing brain perfusion in the deep part of the brain. We concluded that SAH slows brain perfusion recovery.

Hydrocephalus: historical analysis and considerations for treatment

Hydrocephalus is a serious condition that affects patients of all ages, resulting from a multitude of causes. While the etiologies of hydrocephalus are numerous, many of the acute and chronic symptoms of the condition are shared. These symptoms include disorientation and pain (headaches), cognitive and developmental changes, vision and sleep disturbances, and gait abnormalities. This collective group of symptoms combined with the effectiveness of CSF diversion as a surgical intervention for many types of the condition suggest that the various etiologies may share common cellular and molecular dysfunctions. The incidence rate of pediatric hydrocephalus is approximately 0.1–0.6% of live births, making it as common as Down syndrome in infants. Diagnosis and treatment of various forms of adult hydrocephalus remain understudied and underreported. Surgical interventions to treat hydrocephalus, though lifesaving, have a high incidence of failure. Previously tested pharmacotherapies for the treatment of hydrocephalus have resulted in net zero or negative outcomes for patients potentially due to the lack of understanding of the cellular and molecular mechanisms that contribute to the development of hydrocephalus. Very few well-validated drug targets have been proposed for therapy; most of these have been within the last 5 years. Within the last 50 years, there have been only incremental improvements in surgical treatments for hydrocephalus, and there has been little progress made towards prevention or cure. This demonstrates the need to develop nonsurgical interventions for the treatment of hydrocephalus regardless of etiology. The development of new treatment paradigms relies heavily on investment in researching the common molecular mechanisms that contribute to all of the forms of hydrocephalus, and requires the concerted support of patient advocacy organizations, government- and private-funded research, biotechnology and pharmaceutical companies, the medical device industry, and the vast network of healthcare professionals.

Brainstem Hemorrhage Following Lumbar Drain for Post-traumatic Hydrocephalus

Post-traumatic hydrocephalus is common after traumatic brain injury (TBI), particularly following decompressive craniectomy. Cerebrospinal fluid (CSF) removal by lumbar drain (LD) aids in the workup of post-traumatic hydrocephalus and serves as a bridge to definitive CSF diversion. Hemorrhagic complications following LD are rare but can include intracranial hemorrhage. We present a case of fatal brainstem hemorrhage following LD in a patient three months after craniectomy.

A 32-year-old male presented with severe TBI and an acute subdural hematoma. He underwent emergent decompressive craniectomy and hematoma evacuation. The next day, he required ventriculostomy for elevated intracranial pressure (ICP), which was able to be successfully removed. Three months after the injury, the patient’s neurological exam declined, and computed tomography (CT) findings were consistent with communicating hydrocephalus. An LD was placed with 15 mL of CSF and drained every two hours. Five days after LD placement, the CSF became blood-tinged, and a repeat head CT demonstrated an acute brainstem hemorrhage. The patient ultimately expired.

Given the prevalence of post-traumatic hydrocephalus and the frequent use of CSF diversion in the management of this condition, it is important for neurosurgeons to remain cognizant of the potential risk for catastrophic brainstem hemorrhage following LD in decompressive craniectomy patients.

Hydrocephalus and the neuro-intensivist: CSF hydrodynamics at the bedside

Hydrocephalus (HCP) is far more complicated than a simple disorder of cerebrospinal fluid (CSF) circulation. HCP is a common complication in patients with subarachnoid hemorrhage (SAH) and after craniectomy. Clinical measurement in HCP is mainly related to intracranial pressure (ICP) and cerebral blood flow. The ability to obtain quantitative variables that describe CSF dynamics at the bedside before potential shunting may support clinical intuition with a description of CSF dysfunction and differentiation between normal pressure hydrocephalus and brain atrophy. This review discusses the advanced research on HCP and how CSF is generated, stored and absorbed within the context of a mathematical model developed by Marmarou. Then, we proceed to explain the main quantification analysis of CSF dynamics using infusion techniques for deciding on definitive treatment. We consider that such descriptions of multiple parameters of measurements need to be significantly appreciated by the caring neuro-intensivist, for better understanding of the complex pathophysiology and clinical management and finally, improve of the prognosis of these patients with HCP.

In this review article, we present current and novel theories of CSF circulation and pathophysiology of hydrocephalus, along with results from infusion studies for evaluating CSF dynamics at the bedside.

Temporal Horn Enlargements Predict Secondary Hydrocephalus Diagnosis Earlier than Evans' Index

The aim of this study was to identify early radiological signs of secondary hydrocephalus. We retrieved neuroradiological data from scans performed at various times in patients who underwent surgery for secondary hydrocephalus due to severe traumatic brain injury (TBI), subarachnoid haemorrhage (SAH), or brain tumour (BT). Baseline measurements, performed on the earliest images acquired after the neurological event (T0), included Evans’ index, the distance between frontal horns, and the widths of both temporal horns. The next neuroimage that showed an increase in at least one of these four parameters—and that lead the surgeon to act—was selected as an indication of ventricular enlargement (T1). Comparisons of T0 and T1 neuroimages showed increases in Evans’ index, in the mean frontal horn distance, and in the mean right and left temporal horn widths. Interestingly, in T1 scans, mean Evans’ index scores > 0.30 were only observed in patients with BT. However, the temporal horn widths increased up to ten-fold in most patients, independent of Evans’ index scores. In conclusion temporal horn enlargements were the earliest, most sensitive findings in predicting ventricular enlargement secondary to TBI, SAH, or BT. To anticipate a secondary hydrocephalus radiological diagnosis, clinicians should measure both Evans’ index and the temporal horn widths, to avoid severe disability and poor outcome related to temporal lobe damage.

The Value of the Correlation Coefficient Between the ICP Wave Amplitude and the Mean ICP Level (RAP) Combined With the Resistance to CSF Outflow (Rout) for Early Prediction of the Outcome Before Shunting in Posttraumatic Hydrocephalus

Objective

To evaluate the value of the correlation coefficient between the ICP wave amplitude and the mean ICP level (RAP) and the resistance to CSF outflow (Rout) in predicting the outcome of patients with post-traumatic hydrocephalus (PTH) selected for shunting.

Materials and Methods

As a training set, a total of 191 patients with PTH treated with VP shunting were retrospectively analyzed to evaluate the potential predictive value of Rout, collected from pre-therapeutic CSF infusion test, for a desirable recovery level (dRL), standing for the modified rankin scale (mRS) of 0–2. Eventually, there were 70 patients with PTH prospectively included as a validation set to evaluate the value of Rout-combined RAP as a predictor of dRL. We calculated Rout from a CSF infusion test and collected RAP during continuous external lumbar drainage (ELD). Maximum RAP (RAPmax) and its changes relative to the baseline (ΔRAPmax%) served as specific parameters of evaluation.

Results

In the training set, Rout was proved to be a significant predictor of dRL to shunting, with the area under the curve (AUC) of 0.686 (p < 0.001) in receiver-operating characteristic (ROC) analysis. In the validation set, Rout alone did not present a significant value in the prediction of desirable recovery level (dRL). ΔRAPmax% after 1st or 2nd day of ELD both showed significance in predicting of dRL to shunting with the AUC of 0.773 (p < 0.001) and 0.786 (p < 0.001), respectively. Significantly, Rout increased the value of ΔRAPmax% in the prediction of dRL with the AUC of 0.879 (p < 0.001), combining with ΔRAPmax% after the 1st and 2nd days of ELD. RAPmax after the 1st and 2nd days of ELD showed a remarkable predictive value for non-dRL (Levels 3-6 in Modified Rankin Scale) with the AUC of 0.891 (p < 0.001) and 0.746 (p < 0.001).

Conclusion

Both RAP and Rout can predict desirable recovery level (dRL) to shunting in patients with PTH in the early phases of treatment. A RAP-combined Rout is a better dRL predictor for a good outcome to shunting. These findings help the neurosurgeon predict the probability of dRL and facilitate the optimization of the individual treatment plan in the event of ineffective or unessential shunting.

Incidence of surgically treated post-traumatic hydrocephalus 6 months following head injury in patients undergoing acute head computed tomography

BACKGROUND

Post-traumatic hydrocephalus (PTH) is a well-known complication of head injury. The percentage of patients experiencing PTH in trauma cohorts (0.7-51.4%) varies greatly in the prior literature depending on the study population and applied diagnostic criteria. The objective was to determine the incidence of surgically treated PTH in a consecutive series of patients undergoing acute head computed tomography (CT) following injury.

METHODS

All patients (N = 2908) with head injuries who underwent head CT and were treated at the Tampere University Hospital's Emergency Department (August 2010-July 2012) were retrospectively evaluated from patient medical records. This study focused on adults (18 years or older) who were residents of the Pirkanmaa region at the time of injury and were clinically evaluated and scanned with head CT at the Tampere University Hospital's emergency department within 48 h after injury (n = 1941). A thorough review of records for neurological signs and symptoms of hydrocephalus was conducted for all patients having a radiological suspicion of hydrocephalus. The diagnosis of PTH was based on clinical and radiological signs of the condition within 6 months following injury. The main outcome was surgical treatment for PTH. Clinical evidence of shunt responsiveness was required to confirm the diagnosis of PTH.

RESULTS

The incidence of surgically treated PTH was 0.15% (n = 3). Incidence was 0.08% among patients with mild traumatic brain injury (TBI) and 1.1% among those with moderate to severe TBI. All the patients who developed PTH underwent neurosurgery during the initial hospitalization due to the head injury. The incidence of PTH among patients who underwent neurosurgery for acute traumatic intracranial lesions was 2.7%.

CONCLUSION

The overall incidence of surgically treated PTH was extremely low (0.15%) in our cohort. Analyses of risk factors and the evaluation of temporal profiles could not be undertaken due to the extremely small number of cases.

Analysis of relative changes in pulse shapes of intracranial pressure and cerebral blood flow velocity

Objective.Analysis of relative changes in the shapes of pulse waveforms of intracranial pressure (ICP) and transcranial Doppler cerebral blood flow velocity (CBFV) may provide information on intracranial compliance. We tested this hypothesis, introducing an index named the ratio of pulse slopes (RPS) that is based on inclinations of the ascending parts of the ICP and CBFV pulse waveforms. It has hypothetically a simple interpretation: a value of 1 indicates good compliance and a value less than 1, reduced compliance. Here, we investigated the usefulness of RPS for assessment of intracranial compliance.Approach.ICP and CBFV signals recorded simultaneously in 30 normal-pressure hydrocephalus patients during infusion tests were retrospectively analysed. CBFV was measured in the middle cerebral artery. Changes in RPS during the test were compared with changes in the height ratio of the first and second peak of the ICP pulse (P1/P2) and the shape of the ICP pulse was classified from normal (1) to pathological (4). Values are medians (lower, upper quartiles).Main results.There was a significant correlation between baseline RPS and intracranial elasticity (R = -0.55,p = 0.0018). During the infusion tests, both RPS and P1/P2 decreased with rising ICP [RPS, 0.80 (0.56, 0.92) versus 0.63 (0.44, 0.80),p = 0.00015; P1/P2, 0.58 (0.50, 0.91) versus 0.52 (0.36, 0.71),p = 0.00009] while the ICP pulses became more pathological in shape [class: 3 (2, 3) versus 3 (3, 4),p = 0.04]. The magnitude of the decrease in RPS during infusion was inversely correlated with baseline P1/P2 (R = -0.40,p < 0.03).Significance.During infusion, the slopes of the ascending parts of ICP and CBFV pulses become increasingly divergent with a shift in opposite directions. RPS seems to be a promising methodological tool for monitoring intracranial compliance with no additional volumetric manipulation required.

From Shunt to Recovery: A Multidisciplinary Approach to Hydrocephalus Treatment in Severe Acquired Brain Injury Rehabilitation

Background: Hydrocephalus among Severe Acquired Brain Injury (SABI) patients remains overlooked during rehabilitation. Methods: A retrospective cohort study was carried out of traumatic and non-traumatic SABI patients with hydrocephalus, consecutively admitted over 9 years in a tertiary referral specialized rehabilitation hospital. Patients were treated with ventriculoperitoneal shunt before or during inpatient rehabilitation and assessed using the Level of Cognitive Functioning Scale and Disability Rating Scale. Logistic regression models were used to identify predictors of post-surgical complications. Linear regression models were used to investigate predictors of hospital length of stay (LOS), disability, and cognitive function. Results: Of the 82 patients, 15 had post-surgical complications and 16 underwent cranioplasty. Shunt placement complication risk was higher when fixed vs. when programmable pressure valves were used. A total of 56.3% achieved functional improvement at discharge and 88.7% improved in cognitive function; of the 82 patients, 56% were discharged home. In multiple regression analyses, higher disability at discharge was related to cranioplasty and longer LOS, while poorer cognitive function was associated with cranioplasty. Increase in LOS was associated with increasing time to shunt and decreasing age. Conclusions: A significant improvement in cognitive and functional outcomes can be achieved. Cranioplasty increased LOS, and fixed pressure valves were related to poorer outcomes.

Post-injury ventricular enlargement associates with iron in choroid plexus but not with seizure susceptibility nor lesion atrophy-6-month MRI follow-up after experimental traumatic brain injury

Ventricular enlargement is one long-term consequence of a traumatic brain injury, and a risk factor for memory disorders and epilepsy. One underlying mechanisms of the chronic ventricular enlargement is disturbed cerebrospinal-fluid secretion or absorption by choroid plexus. We set out to characterize the different aspects of ventricular enlargement in lateral fluid percussion injury (FPI) rat model by magnetic resonance imaging (MRI) and discovered choroid plexus injury in rats that later developed hydrocephalus. We followed the brain pathology progression for 6 months and studied how the ventricular growth was associated with the choroid plexus injury, cortical lesion expansion, hemorrhagic load or blood perfusion deficits. We correlated MRI findings with the seizure susceptibility in pentylenetetrazol challenge and memory function in Morris water-maze. Choroid plexus injury was validated by ferric iron (Prussian blue) and cytoarchitecture (Nissl) stainings. We discovered choroid plexus injury that accumulates iron in 90% of FPI rats by MRI. The amount of the choroid plexus iron remained unaltered 1-, 3- and 6-month post-injury. During this time, the ventricles kept on growing bilaterally. Ventricular growth did not depend on the cortical lesion severity or the cortical hemorrhagic load suggesting a separate pathology. Instead, the results indicate choroidal injury as one driver of the post-traumatic hydrocephalus, since the higher the choroid plexus iron load the larger were the ventricles at 6 months. The ventricle size or the choroid plexus iron load did not associate with seizure susceptibility. Cortical hypoperfusion and memory deficits were worse in rats with greater ventricular growth.

Post Traumatic Hydrocephalus: Incidence, Pathophysiology and Outcomes

Background

Post-traumatic hydrocephalus (PTH) is a sequel of traumatic brain injury (TBI) that is seen more often in patients undergoing decompressive craniectomy (DC). It is associated with prolonged hospital stay and unfavorable outcomes.

Objective

To study the incidence and risk factors for development of PTH in patients undergoing DC in our institution and to review the literature on PTH with respect to incidence, risk factors, pathophysiology, and outcomes of management.

Methods

Data from 95 patients (among 220 patients who underwent DC for TBI and fulfilled the inclusion criteria) over a 5-year period at Christian Medical College, Vellore were collected and analyzed to study the incidence and possible risk factors for development of PTH. A review of the literature on PTH was performed by searching PUBMED resources.

Results

Thirty (31.6%) out of 95 patients developed post-traumatic ventriculomegaly, of whom seven (7.3%) developed symptomatic PTH, necessitating placement of ventriculoperitoneal shunt (VPS). No risk factor for development of PTH could be identified. The reported incidence of PTH in the literature is from 0.07% to 29%, with patients undergoing DC having a higher incidence. Younger age, subarachnoid hemorrhage, severity of TBI, presence of subdural hygroma, and delayed cranioplasty after DC are the main risk factors reported in the literature.

Conclusions

PTH occurs in a significant proportion of patients with TBI and can lead to unfavorable outcomes. PTH has to be distinguished from asymptomatic ventriculomegaly as early as possible so that a CSF diversion procedure can be planned early during development of PTH.

Hydrocephalus and Cerebrospinal Fluid Analysis Following Severe Traumatic Brain Injury: Evaluation of a Prospective Cohort

The development of hydrocephalus after severe traumatic brain injury (TBI) is an under-recognized healthcare phenomenon and can increase morbidity. The current study aims to characterize post-traumatic hydrocephalus (PTH) in a large cohort. Patients were prospectively enrolled age 16-80 years old with Glasgow Coma Scale (GCS) score ≤8. Demographics, GCS, Injury Severity Score (ISS), surgery, and cerebrospinal fluid (CSF) were analyzed. Outcomes were shunt failure and Glasgow Outcome Scale (GOS) at 6 and 12-months. Statistical significance was assessed at p < 0.05. In 402 patients, mean age was 38.0 ± 16.7 years and 315 (78.4%) were male. Forty (10.0%) patients developed PTH, with predominant injuries being subdural hemorrhage (36.4%) and diffuse axonal injury (36.4%). Decompressive hemicraniectomy (DHC) was associated with hydrocephalus (OR 3.62, 95% CI (1.62-8.07), p < 0.01). Eighteen (4.5%) patients had shunt failure and proximal obstruction was most common. Differences in baseline CSF cell count were associated with increased shunt failure. PTH was not associated with worse outcomes at 6 (p = 0.55) or 12 (p = 0.47) months. Hydrocephalus is a frequent sequela in 10.0% of patients, particularly after DHC. Shunt placement and revision procedures are common after severe TBI, within the first 4 months of injury and necessitates early recognition by the clinician.

Post-traumatic hydrocephalus - incidence, risk factors, treatment, and clinical outcome

OBJECTIVES

Post-traumatic hydrocephalus (PTH) is well-known after traumatic brain injury (TBI), but there is limited evidence regarding patient selection for ventriculo-peritoneal (VP)-shunt treatment. In this study, we investigated the incidence and risk factors for PTH and the indication for and outcome after shunt treatment.

MATERIALS AND METHODS

In this retrospective study, 836 TBI patients, treated at our neurointensive care (NIC) unit at Uppsala university hospital, Sweden, between 2008 and 2018, were included. Demography, admission status, radiology, treatments, and outcome variables were evaluated.

RESULTS

Post-traumatic ventriculomegaly occurred in 46% of all patients at NIC discharge. Twenty-nine (3.5%) patients received a VP-shunt. Lower GCS M at admission, greater amount of subarachnoid hemorrhage, meningitis, decompressive craniectomy (DC), and ventriculomegaly at NIC discharge were risk factors for receiving a VP-shunt. Fourteen of the PTH patients showed impeded recovery or low-pressure hydrocephalus symptoms, of whom 13 experienced subjective clinical improvement after shunt treatment. Five PTH patients showed deterioration in consciousness, of whom four improved following shunt treatment. Five DC patients received a shunt due to subdural hygromas (n =2) or external brain herniation (n = 3), of whom two patients improved following treatment. Five patients were vegetative with concurrent ventriculomegaly and these patients did not have any positive shunt response. Altogether, 19 (66%) PTH patients improved after shunt surgery.

CONCLUSION

Post-traumatic ventriculomegaly was common, but few developed symptomatic PTH and received a VP-shunt. Patients with low-pressure hydrocephalus symptoms had the best shunt response, whereas patients with suspected vegetative state exhibited a minimal shunt response.

Assessment of Pressure-Volume Index During Lumbar Infusion Study: What Is the Optimal Method?

INTRODUCTION

Assessment of the pressure-volume index (PVI) during lumbar infusion study (LIS) has been proposed to evaluate the overall compliance of the cranio-spinal system. It is calculated from the measurement of CSF pressure changes, ΔP from Pb to Pp, in response to repeated bolus injections of a volume (ΔV) within the lumbar subarachnoid space.

MATERIAL AND METHODS

We retrospectively analyzed 18 patients who underwent LIS for suspicion of normal pressure hydrocephalus, including a series of three fast bolus injections of 3 mL of saline at different levels of CSF pressure. We compared two methods for PVI calculation: (a) PVI_slope using the slope α of a linear fit ΔP = α(Pb - P ₀), PVI = ΔV/log₁₀(α + 1); (b) PVI_mean using the PVI calculated independently for each bolus injection assuming P ₀ = 0, PVI = mean(ΔV/log₁₀(Pp_i/Pb_i))_i=1.3.

RESULTS

We found a significant discrepancy between the two methods: the average difference (PVI_slope - PVI_mean) was -3.93 mL (95% confidence interval [8.77; -16.64]). In the PVI_slope, method, the mean P ₀ was 2.12 mmHg (±3.41 mmHg).

DISCUSSION

The clinical reliability of PVI_mean (assuming P ₀ = 0) depends on the value of P ₀. PVI_slope provides results, independent of P ₀. Future studies should focus on determining pathological PVI range rather than fixed cut-off values.

Differences in Cerebrospinal Fluid Dynamics in Posttraumatic Hydrocephalus Versus Atrophy, Including Effect of Decompression and Cranioplasty

INTRODUCTION

Challenges in diagnosing post-traumatic hydrocephalus (PTH) have created a need for an accurate diagnostic tool. We aim to report CSF dynamics in PTH and atrophy, along with differences before and after cranioplasty.

METHODS

We retrospectively analyzed traumatic brain injury patients with ventriculomegaly who had infusion studies. We divided patients depending on CSF dynamics into two groups: 'likely PTH' (A) and 'likely atrophy' (B). A group of idiopathic normal pressure hydrocephalus shunt-responsive patients was used for comparison (C).

RESULTS

Group A consisted of 36 patients who were non-decompressed or had a cranioplasty in situ for over 1 month. Group B included 16 patients with low Rout, AMP, and dAMP, 9 of whom were decompressed. Rout and dAMP were significantly higher in Group A than B, but significantly lower than Group C (45 iNPH patients). RAP change during infusion in group A indicated depleted compensatory reserve compared to ample reserve in group B. Repeat studies in five decompressed patients post-cranioplasty showed all parameters increased.

CONCLUSIONS

Infusion tests are not useful in decompressed patients, whilst cranioplasty allowed differentiation between possible PTH and atrophy. Rout and AMP were significantly lower in PTH compared to iNPH and did not always reflect the degree of hydrocephalus reported on imaging.

CSF Dynamics for Shunt Prognostication and Revision in Normal Pressure Hydrocephalus

BACKGROUND

Despite the quantitative information derived from testing of the CSF circulation, there is still no consensus on what the best approach could be in defining criteria for shunting and predicting response to CSF diversion in normal pressure hydrocephalus (NPH).

OBJECTIVE

We aimed to review the lessons learned from assessment of CSF dynamics in our center and summarize our findings to date. We have focused on reporting the objective perspective of CSF dynamics testing, without further inferences to individual patient management.

DISCUSSION

No single parameter from the CSF infusion study has so far been able to serve as an unquestionable outcome predictor. Resistance to CSF outflow (Rout) is an important biological marker of CSF circulation. It should not, however, be used as a single predictor for improvement after shunting. Testing of CSF dynamics provides information on hydrodynamic properties of the cerebrospinal compartment: the system which is being modified by a shunt. Our experience of nearly 30 years of studying CSF dynamics in patients requiring shunting and/or shunt revision, combined with all the recent progress made in producing evidence on the clinical utility of CSF dynamics, has led to reconsidering the relationship between CSF circulation testing and clinical improvement.

CONCLUSIONS

Despite many open questions and limitations, testing of CSF dynamics provides unique perspectives for the clinician. We have found value in understanding shunt function and potentially shunt response through shunt testing in vivo. In the absence of infusion tests, further methods that provide a clear description of the pre and post-shunting CSF circulation, and potentially cerebral blood flow, should be developed and adapted to the bed-space.

CT Findings and Histological Evaluation of Red Foxes (Vulpes vulpes) with Chronic Head Trauma Injury: A Retrospective Study

Large numbers of wild animals are injured every year in road traffic accidents. Scant data are available for rescued wild carnivores, in particular for red foxes. Cases of foxes with head trauma were retrospectively considered for inclusion in this study. Clinical examination, modified Glasgow coma scale (MGCS), computed tomography (CT) examination, therapy, outcome, and post mortem findings of the brain were investigated. In all foxes, cranial vaults lesion occurred in single (67%) or multiple sites (33%). Midline shift and hydrocephalus were observed in this population. The mean survival was 290 (±176) days. In our study, we performed CT scans on average 260 days after fox rescue, and we speculate that persisting clinical signs could be attributed to TBI. In our study, only two foxes were alive at the time of writing. Other foxes were euthanized due to the severity of the clinical signs. CT scans help diagnose chronic lesions and their effect on prognostic judgment for animals released to wildlife environments.

Consensus statement from the international consensus meeting on post-traumatic cranioplasty

Background

Due to the lack of high-quality evidence which has hindered the development of evidence-based guidelines, there is a need to provide general guidance on cranioplasty (CP) following traumatic brain injury (TBI), as well as identify areas of ongoing uncertainty via a consensus-based approach.

Methods

The international consensus meeting on post-traumatic CP was held during the International Conference on Recent Advances in Neurotraumatology (ICRAN), in Naples, Italy, in June 2018. This meeting was endorsed by the Neurotrauma Committee of the World Federation of Neurosurgical Societies (WFNS), the NIHR Global Health Research Group on Neurotrauma, and several other neurotrauma organizations. Discussions and voting were organized around 5 pre-specified themes: (1) indications and technique, (2) materials, (3) timing, (4) hydrocephalus, and (5) paediatric CP.

Results

The participants discussed published evidence on each topic and proposed consensus statements, which were subject to ratification using anonymous real-time voting. Statements required an agreement threshold of more than 70% for inclusion in the final recommendations.

Conclusions

This document is the first set of practical consensus-based clinical recommendations on post-traumatic CP, focusing on timing, materials, complications, and surgical procedures. Future research directions are also presented.

External Hydrocephalus After Traumatic Brain Injury: Retrospective Study of 102 Patients

INTRODUCTION

External hydrocephalus (EH) refers to impairment of extra-axial cerebrospinal fluid flow with enlargement of the subarachnoid space (SAS) and concomitant raised intracranial pressure (ICP). It is often confused with a subdural hygroma and overlooked, particularly when there is no ventricular enlargement. In this study, we aimed to describe the epidemiology of EH in a large population of adults with traumatic brain injury (TBI).

METHODS

This observational, retrospective cohort study was conducted in adult patients who were admitted with TBI to the Department of Clinical Neuroscience at Addenbrooke's Hospital (Cambridge, UK) over a period of 3 years (2014-2017). Patients were included in the study if they had ICP monitoring and at least three CT scans within the first 21 days to assess SAS evolution. Patients who underwent a decompressive craniectomy were excluded. SAS was assessed individually on each CT scan by two independent investigators. ICP data were analysed with ICM+ software (Cambridge Enterprise Ltd., Cambridge, UK). Short-term and 6-month outcomes were examined. The groups of patients with and without EH were compared.

RESULTS

Of the 102 patients included in the study, 30.4% developed EH after a delay of 2.98 ± 2.4 days. The initial Glasgow Coma Scale (GCS) scores did not differ between patients with and without EH. Subarachnoid haemorrhage was found to be the main risk factor for EH. Patients with EH required a significantly longer period of mechanical ventilation (+6.9 days), were more likely to have a tracheostomy (55% versus 33%), and had a longer stay in the intensive care unit (+8.5 days). ICP was higher during the 48 h after diagnosis of EH than during the previous 48 h. EH survivors had a lower mean Glasgow Outcome Scale Extended (GOS-E) score (4.6 versus 5.9, P = 0.031) and were more likely to receive a permanent shunt for secondary hydrocephalus (17.4% versus 1.8%, odds ratio 7.1).

CONCLUSION

In adults with TBI, EH remains insufficiently understood and probably underdiagnosed. This study showed that it is a frequent complication of TBI, with significant clinical consequences.

Simultaneous cranioplasty and ventriculoperitoneal shunt placement in patients with traumatic brain injury undergoing unilateral decompressive craniectomy

Hydrocephalus is a common complication after decompressive craniectomy (DC) in patients with traumatic brain injury (TBI). However, the strategy of managing TBI patients with a cranial defect and hydrocephalus remains controversial. Placement of a ventriculoperitoneal shunt (VPS) in patients with a cranial defect and hydrocephalus may aggravate sinking skin flap overlying the cranial defect and result in syndrome of sinking skin flap (SSSF) that causes neurological deterioration. A retrospective analysis of 49 TBI patients who developed hydrocephalus after unilateral DC was undertaken to investigate the safety of simultaneous cranioplasty and VPS placement, and the incidence of SSSF after VPS placement. Among these patients, 17 patients underwent simultaneous cranioplasty and VPS placement, and 32 patients underwent staged cranioplasty and VPS placement. The overall complication rate was 9.3% (3/32) in staged group and 29.4% (5/17) in simultaneous group, respectively. There was no statistically significance between two study groups regarding overall complication (p = 0.11) and reoperation rate (p = 0.47). Two patients with severe brain bulging in staged group developed SSSF after placement of a nonprogrammable VPS. Our study showed that simultaneous cranioplasty and VPS placement may be safe in TBI patients with a cranial defect and hydrocephalus. However, due to the contradictory results about the safety of simultaneous cranioplasty and VPS placement in the literatures, neurosurgeons should carefully consider whether patients are suitable for such treatment. In patients planning to undergo VPS placement first, a programmable shunt may be a better choice for the possibility of SSSF after shunt placement.

Early cranioplasty associated with a lower rate of post-traumatic hydrocephalus after decompressive craniectomy for traumatic brain injury

BACKGROUND

Post-traumatic hydrocephalus (PTH) is one of the primary complications during the course of traumatic brain injury (TBI). The aim of this study was to define factors associated with the development of PTH in patients who underwent unilateral decompressive craniectomy (DC) for TBI.

METHODS

A total of 126 patients, who met the inclusion criteria of the study, were divided into two groups: patients with PTH (n = 25) and patients without PTH (n = 101). Their demographic, clinical, radiological, operative, and postoperative factors, which may be associated with the development of PTH, were compared.

RESULTS

Multivariate logistic regression analysis revealed that cranioplasty performed later than 2 months following DC was significantly associated with the requirement for ventriculoperitoneal shunting due to PTH (p < 0.001). Also, a significant unfavorable outcome rate was observed in patients with PTH at 1-year follow-up according to the Glasgow Outcome Scale-Extended (p = 0.047).

CONCLUSIONS

Our results show that early cranioplasty within 2 months after DC was associated with a lower rate of PTH development after TBI.

Does the skull Hounsfield unit predict shunt dependent hydrocephalus after decompressive craniectomy for traumatic acute subdural hematoma?

Background and purpose

Posttraumatic hydrocephalus affects 11.9%–36% of patients undergoing decompressive craniectomy (DC) after traumatic brain injury and necessitates a ventriculo-peritoneal shunt placement. As bone and arachnoid trabeculae share the same collagen type, we investigated possible connections between the skull Hounsfield unit (HU) values and shunt-dependent hydrocephalus (SDHC) in patients that received cranioplasty after DC for traumatic acute subdural hematoma (SDH).

Methods

We measured HU values in the frontal bone and internal occipital protuberance from admission brain CT. Receiver operating characteristic curve analysis was performed to identify the optimal cut-off skull HU values for predicting SDHC in patients receiving cranioplasty after DC due to traumatic acute SDH. We investigated independent predictive factors for SDHC occurrence using multivariable logistic regression analysis.

Results

A total of 162 patients (>15 years of age) were enrolled in the study over an 11-year period from two university hospitals. Multivariable logistic analysis revealed that the group with simultaneous frontal skull HU ≤797.4 and internal occipital protuberance HU ≤586.5 (odds ratio, 8.57; 95% CI, 3.05 to 24.10; P<0.001) was the only independent predictive factor for SDHC in patients who received cranioplasty after DC for traumatic acute SDH.

Conclusions

Our study reveals a potential relationship between possible low bone mineral density and development of SDHC in traumatic acute SDH patients who had undergone DC. Our findings provide deeper insight into the association between low bone mineral density and hydrocephalus after DC for traumatic acute SDH.

Cerebrospinal fluid dynamics in non-acute post-traumatic ventriculomegaly

Background

Post-traumatic hydrocephalus (PTH) is potentially under-diagnosed and under-treated, generating the need for a more efficient diagnostic tool. We aim to report CSF dynamics of patients with post-traumatic ventriculomegaly.

Materials and methods

We retrospectively analysed post-traumatic brain injury (TBI) patients with ventriculomegaly who had undergone a CSF infusion test. We calculated the resistance to CSF outflow (Rout), AMP (pulse amplitude of intracranial pressure, ICP), dAMP (AMPplateau-AMPbaseline) and compensatory reserve index correlation coefficient between ICP and AMP (RAP). To avoid confounding factors, included patients had to be non-decompressed or with cranioplasty > 1 month previously and Rout > 6 mmHg/min/ml. Compliance was assessed using the elasticity coefficient. We also compared infusion-tested TBI patients selected for shunting versus those not selected for shunting (consultant decision based on clinical and radiological assessment and the infusion results). Finally, we used data from a group of shunted idiopathic Normal Pressure Hydrocephalus (iNPH) patients for comparison.

Results

Group A consisted of 36 patients with post-traumatic ventriculomegaly and Group B of 45 iNPH shunt responders. AMP and dAMP were significantly lower in Group A than B (0.55 ± 0.39 vs 1.02 ± 0.72; p < 0.01 and 1.58 ± 1.21 vs 2.76 ± 1.5; p < 0.01. RAP baseline was not significantly different between the two. Elasticity was higher than the normal limit in all groups (average 0.18 1/ml). Significantly higher Rout was present in those with probable PTH selected for shunting compared with unshunted. Mild/moderate hydrocephalus, ex-vacuo ventriculomegaly/encephalomalacia were inconsistently reported in PTH patients.

Conclusions

Rout and AMP were significantly lower in PTH compared to iNPH and did not always reflect the degree of hydrocephalus or atrophy reported on CT/MRI. Compliance appears reduced in PTH.

Incidence of hydrocephalus in traumatic brain injury: A nationwide population-based cohort study

BACKGROUND

The aim of this study was to investigate the risk and peak time of post-traumatic hydrocephalus (PTH) in traumatic brain injury (TBI) patients with traumatic subarachnoid hemorrhage (SAH), compared to TBI patients without traumatic SAH.

METHODS

In this retrospective population-based cohort study, the data was extracted from Longitudinal Health Insurance Database from 2000 to 2010 in Taiwan. A total of 23,775 TBI patients who had a first event TBI during 2000 to 2010 were included and divided into TBI with SAH (TBI-S) group and TBI without SAH (TBI-NS) group. We focused on analyzing the PTH in both groups within 2 years after brain injury. Competing risk regression models were performed to assess the risk of developing PTH in the TBI-S group compared to the TBI-NS group.

RESULTS

Comparing to the TBI-NS group, there was a significantly higher cumulative incidence of PTH in the TBI-S group during the 2-year follow-up period. The adjusted hazard ratio (HR) of PTH in TBI-S group within 2 years was between 2.90-3.47, and the highest estimates were obtained within 6 months after injury (HR = 3.47, 95% CI: 2.43-4.94). The occurrence percentage of PTH was highest during 0-3rd month follow-up periods (1.95% in TBI-S group; 0.48% in TBI-NS group).

CONCLUSIONS

The peak time of PTH occurrence was noted during 0-3rd month post brain injury. Traumatic SAH patients had an approximate 3-fold risk of developing PTH, comparing to TBI patients without traumatic SAH.

The Conundrum of Ventricular Dilatations Following Decompressive Craniectomy: Is Ventriculoperitoneal Shunt, The Only Panacea?

Introduction:

Ventriculomegaly and hydrocephalus (HCP) are sometimes a bewildering sequela of decompressive craniectomy (DC). The distinguishing criteria between both are less well defined. Majority of the studies quoted in the literature have defined HCP radiologically, rather than considering the clinical status of the patient. Accordingly, these patients have been treated with permanent cerebrospinal fluid (CSF) diversion procedures. We hypothesize that asymptomatic ventriculomegaly following DC should undergo aspiration with cranioplasty and be followed up regularly.

Materials and Methods:

All patients with post-DC who were scheduled for cranioplasty and satisfied the radiological criteria for HCP were included. These patients were categorized into two groups. Group 1 included ventriculomegaly with clinical signs attributable to HCP and Group 2 constituted ventriculomegaly but no clinical signs attributable to HCP. All patients in Group 1 underwent ventriculoperitoneal shunt followed by cranioplasty, whereas all patients in Group 2 underwent cranioplasty along with simultaneous ventriculostomy and temporary aspiration of the lateral ventricle. All patients were regularly followed as the outpatient basis.

Results:

There were 21 patients who developed ventriculomegaly following DC. There were 10 patients in Group 1 and 11 patients in Group 2. The average duration of follow-up was from 6 months to 2 years. Two patients in the shunt group - (group 1) had over drainage and required revision. One patient in aspiration group - (group 2) required permanent CSF diversion.

Conclusions:

Cranioplasty with aspiration is a viable option in selected group of patients in whom there is ventriculomegaly but no signs or symptoms attributable to HCP.

Transcalvarial brain herniation volume as a predictor of posttraumatic hydrocephalus after decompressive craniectomy

OBJECTIVES

In patients undergoing decompressive craniectomy for traumatic brain injury(TBI) there has been reported an incidence of hydrocephalus between 0-45%. There are several radiological and clinical features described in association with development of hydrocephalus. For study the influence of these factors we conducted a retrospective observational single-center cohort study in a tertiary care center with special attention to the transcalvarial herniation(TCH) volume after decompressive craniectomy.

PATIENTS AND METHODS

We selected 50 patients that underwent decompressive craniectomy after closed head injury between january 2014 and January 2015. Hydrocephalus was defined as a modified frontal horn index greater than 33%, presence of Gudeman CT scan criteria or insertion of ventriculoperitoneal Shunt. Variables analyzed were: age, post-resuscitation Glasgow coma scale (GCS) score, pupil reactivity, Zunkeller index, presence of hygroma, TCH volume, craniectomy diameter and distance of craniectomy from midline. Logistic regression was used with hydrocephalus as the primary outcome measure.

RESULTS

17 patients developed hydrocephalus (34%). TCH volume after decompression(p < 0.01), subdural hygroma (p < 0.01), lower admission Glasgow Coma Scale score (p = 0.015), unilateral pupil reactivity(p = 0.042) and higher Zumkeller index(p = 0.044) were significant risk factors for hydrocephalus. Logistic regression analysis showed that factors independently associated with the development of hydrocephalus was the TCH volume (odds ratio 11.08; 95%CI 2.10, 58.4; p = 0.0046), and presence of hygroma (odds ratio 49.59; 95%IC 4.1, 459; p = 0.002).

CONCLUSIONS

There was a clear association between severity of TBI, TCH volume and subdural hygroma with the development of hydrocephalus. Clinicians should follow closely patients with those findings in order to avoid late deterioration.

[CSF shunting surgery in patients with post-traumatic hydrocephalus in the vegetative status and minimally conscious state: analysis of its efficacy and safety]

The development of post-traumatic hydrocephalus (PTH) after severe traumatic brain injury can cause, in some cases, severe impairment of consciousness and prevent rehabilitation of patients. The influence of cerebrospinal fluid (CSF) circulation disorders on processes of consciousness recovery is a fundamental problem that requires in-depth research. The issues of differential diagnosis, results of surgical treatment of PTH, and its complications in patients in the vegetative status (VS) and minimally conscious state (MCS) remain poorly covered.

MATERIAL AND METHODS

We performed a retrospective analysis of the long-term outcomes of surgical treatment in 82 PTH patients in the VS (38 cases) and MCS (44 cases).

RESULTS

A significant clinical improvement occurred in 60.6% of VS patients and in 65.9% of MCS patients. The rate of shunt infection was high and amounted to 21.05% in the group of VS patients and 20.4% in the group of MCS patients. The rate of shunt system dysfunction was 26.05% in the first group and 20.4% in the second group. Postoperative mortality (associated directly with treatment complications) was 3.6%. Total mortality was 10.9%.

DISCUSSION

The positive effect of shunting surgery in patients with gross impairment of consciousness was associated with transition to higher levels of consciousness. The high rate of complications, especially infections, was due to a serious condition of patients and comorbidities, in particular chronic infection foci. Shunt system dysfunction was not a factor of the adverse outcome of surgical treatment because rarely led to irreversible consequences, but required repeated surgery. Mortality after shunting surgery was significantly higher in patients with gross impairment of consciousness than in other groups of patients. We found a correlation between deaths in VS patients and shunt infection in the postoperative period.

CONCLUSION

CSF shunting surgery is an important step in surgical rehabilitation of PTH patients. To assess the contribution of various risk factors to the development of shunt infection and to develop measures reducing its rate, further prospective studies are needed.

Clinical Feature and Outcomes of Secondary Hydrocephalus Caused by Head Trauma

Objective

Post-traumatic hydrocephalus (PTH) is a frequent and serious complication following brain injury. The incidence of PTH varies greatly among studies. The purpose of this study was to investigate the incidence and treatment of PTH in patients with head trauma.

Methods

We examined 956 patients with head trauma who visited our center from January 2012 to December 2015. The hydrocephalus diagnosis was based on radiologic findings and clinical features, and patients were classified into the mild (Group 1, Glasgow Coma Scale score [GCS] 13–15), moderate (Group 2, GCS 9–12), or severe (Group 3, GCS 3–8) brain injury group according to their GCS at admission. To compare these groups, we used age, gender, radiologic findings, PTH developmental period, and postoperative results (Glasgow Outcome Scale).

Results

Of the 956 patients, 24 (2.5%) developed PTH. PTH occurred in 11 (1.4%), 3 (5.6%), and 10 (7.0%) patients in Groups 1, 2, and 3, respectively. Of the 24 patients with PTH, 22 (91.7%) developed PTH within 12 weeks post-trauma; the higher the GCS, the later the onset, and the lower the GCS, the earlier the onset (p=0.019). Twenty-one patients underwent ventriculoperitoneal shunting, and 13 had improved symptoms.

Conclusion

The incidence of PTH cannot be ignored. The possibility of PTH needs to be considered in patients with head trauma and appropriate follow-up should be undertaken. PTH is a treatable complication and patients' quality of life and neurological status can be improved if the appropriate treatment is selected and applied.

Intracranial Hypotension and Hypertension Associated With Reconstructive Cranioplasty After Decompressive Craniectomy: Report of a Lethal Complication With Recommended Strategies for Future Avoidance

Reconstructive cranioplasty can be associated with many complications and add to the not insignificant potential risks associated with decompressive craniectomy. In the setting of post-traumatic hydrocephalus, treatment with a ventriculoperitoneal (VP) shunt prior to reconstructive cranioplasty likely increases these risks even further. The authors report a case of a 17-year-old male with a history of a severe closed head injury who initially suffered a life-threatening complication associated with intracranial hypotension after cranioplasty only to succumb to malignant intracranial hypertension following a second cranioplasty attempt. To our knowledge, this is the first description of a single patient developing both these disparate complications after reconstructive cranioplasty and emphasizes the likely synergistic hazards involved with decompressive craniectomy in the setting of a VP shunt in particular and the overall myriad potential complications that may be associated with reconstructive cranioplasty in general.

[Modern diagnostics and treatment of posttraumatic hydrocephalus]

One of the frequent consequences of severe traumatic brain injury is posttraumatic hydrocephalus that not only hampers the processes of consciousness recovery, rehabilitation, and social adaptation of patients but also is the cause of disability. Pathological processes underlying the clinical picture of posttraumatic hydrocephalus and the relationship between CSF circulation disorders and structural changes in the brain substance have not been adequately studied. Of particular importance are patients in the chronic vegetative or minimally conscious state, recovery from which is blocked by posttraumatic hydrocephalus. The question of reversibility of impaired consciousness depending on the disease duration has remained open. High risks of purulent-inflammatory complications of shunting surgery are especially important in patients with chronic infection foci (tracheostomy, gastrostomy, epicystostomy, prolonged bladder catheterization, pressure ulcers, etc.), but their actual effect on the shunting outcomes has not been revealed. Posttraumatic hydrocephalus remains a topical neurosurgical problem requiring clarification of its diagnostic criteria, differentiation from atrophy-related ventriculomegaly, and comprehensive development of pathogenetic and therapeutic aspects.

Rehabilitation Needs of the Elder with Traumatic Brain Injury

The incidence of traumatic brain injury (TBI) in older adults is increasing. As the expected life expectancy increases, there is a heightened need for comprehensive rehabilitation for this population. Elderly patients with TBI benefit from rehabilitation interventions at all stages of injury and can achieve functional gains during acute inpatient rehabilitation. Clinicians should be vigilant of unique characteristics of this population during inpatient rehabilitation, including vulnerability to polypharmacy, posttraumatic hydrocephalus, neuropsychiatric sequelae, sleep disturbances, and sensory deficits. Long-term care should include fall prevention, assessment of cognitive deficits, aerobic activity, community reintegration, and caretaker support. Life expectancy is reduced after TBI.

Impact of timing of ventriculoperitoneal shunt placement on outcome in posttraumatic hydrocephalus

OBJECTIVE

Posttraumatic hydrocephalus (PTH) is a frequent sequela of traumatic brain injury (TBI) and complication of related cranial surgery. The roles of PTH and the timing of cerebrospinal fluid (CSF) shunt placement in TBI outcome have not been well described. The goal of this study was to assess the impact of hydrocephalus and timing of ventriculoperitoneal (VP) shunt placement on outcome during inpatient rehabilitation after TBI.

METHODS

In this cohort study, all TBI patients admitted to Craig Hospital between 2009 and 2013 were evaluated for PTH, defined as ventriculomegaly, and hydrocephalus symptoms, delayed or deteriorating recovery, or elevated opening pressure on lumbar puncture. Extent of ventriculomegaly was quantified by the Evans index from CT scans. Outcome measures were emergence from and duration of posttraumatic amnesia (PTA) and functional status as assessed by means of the Functional Independence Measure (FIM). Findings in this group were compared to findings in a group of TBI patients without PTH (controls) who were admitted for inpatient rehabilitation during the same study period and met specific criteria for inclusion.

RESULTS

A total of 701 patients were admitted with TBI during the study period. Of these patients, 59 (8%) were diagnosed with PTH and were included in this study as the PTH group, and 204 who were admitted for rehabilitation and met the criteria for inclusion as controls constituted the comparison group (no-PTH group). PTH was associated with initial postinjury failure to follow commands, midline shift or cistern compression, subcortical contusion, and craniotomy or craniectomy. In multivariable analyses, independent predictors of longer PTA duration and lower FIM score at rehabilitation discharge were PTH, emergency department Glasgow Coma Scale motor score < 6, and longer time from injury to rehabilitation admission. PTH accounted for a 51-day increase in PTA duration and a 29-point reduction in discharge FIM score. In 40% of PTH patients with preshunt CT brain imaging analyzed, ventriculomegaly (Evans index > 0.3) was observed 3 or more days before VP shunt placement (median 10 days, range 3-102 days). Among PTH patients who received a VP shunt, earlier placement was associated with better outcome by all measures assessed and independently predicted better FIM total score and shorter PTA duration.

CONCLUSIONS

Posttraumatic hydrocephalus predicts worse outcome during inpatient rehabilitation, with poorer functional outcomes and longer duration of PTA. In shunt-treated PTH patients, earlier CSF shunting predicted improved recovery. These results suggest that clinical vigilance for PTH onset and additional studies on timing of CSF diversion are warranted.

Factors Associated Postoperative Hydrocephalus in Patients with Traumatic Acute Subdural Hemorrhage

Objective

Postoperative hydrocephalus is a common complication following craniectomy in patients with traumatic brain injury, and affects patients' long-term outcomes. This study aimed to verify the risk factors associated with the development of hydrocephalus after craniectomy in patients with acute traumatic subdural hemorrhage (tSDH).

Methods

Patients with acute traumatic SDH who had received a craniectomy between December 2005 and January 2016 were retrospectively assessed by reviewing the coexistence of other types of hemorrahges, measurable variables on computed tomography (CT) scans, and the development of hydrocephalus during the follow-up period.

Results

Data from a total of 63 patients who underwent unilateral craniectomy were analyzed. Postoperative hydrocephalus was identified in 34 patients (54%) via brain CT scans. Preoperative intraventricular hemorrhage (IVH) was associated with the development of hydrocephalus. Furthermore, the thickness of SDH (p=0.006) and the extent of midline shift before craniectomy (p=0.001) were significantly larger in patients with postoperative hydrocephalus. Indeed, multivariate analyses showed that the thickness of SDH (p=0.019), the extent of midline shift (p<0.001) and the coexistence of IVH (p=0.012) were significant risk factors for the development of postoperative hydrocephalus. However, the distance from the midline to the craniectomy margin was not an associated risk factor for postoperative hydrocephalus.

Conclusion

In patients with acute traumatic SDH with coexisting IVH, a large amount of SDH, and a larger midline shift, close follow-up is necessary for the early prediction of postoperative hydrocephalus. Furthermore, craniectomy margin need not be limited in acute traumatic SDH patients for the reason of postoperative hydrocephalus.

Decompressive craniectomy and CSF disorders in children

INTRODUCTION

Decompressive craniectomy (DC) is a lifesaving procedure but is associated to several post-operative complications, namely cerebrospinal fluid (CSF) dynamics impairment. The aim of this multicentric study was to evaluate the incidence of such CSF alterations after DC and review their impact on the overall outcome.

MATERIAL AND METHODS

We performed a retrospective multicentric study to analyze the CSF disorders occurring in children aged from 0 to 17 years who had undergone a DC for traumatic brain injury (TBI) in the major Departments of Pediatric Neurosurgery of France between January 2006 and August 2016.

RESULTS

Out of 150 children, ranging in age between 7 months and 17 years, mean 10.75 years, who underwent a DC for TBI in 10 French pediatric neurosurgical centers. Sixteen (6 males, 10 females) (10.67%) developed CSF disorders following the surgical procedure and required an extrathecal CSF shunting. External ventricular drainage increased the risk of further complications, especially cranioplasty infection (p = 0.008).

CONCLUSION

CSF disorders affect a minority of children after DC for TBI. They may develop early after the DC but they may develop several months after the cranioplasty (8 months), consequently indicating the necessity of clinical and radiological close follow-up after discharge from the neurosurgical unit. External ventricular drainage and permanent CSF shunt placement increase significantly the risk of cranioplasty infection.

Using external lumbar CSF drainage to treat communicating external hydrocephalus in adult patients after acute traumatic or non-traumatic brain injury

BACKGROUND

Despite various treatments to control intracranial pressure (ICP) after brain injury, patients may present a late onset of high ICP or a poor response to medications. External lumbar drainage (ELD) can be considered a therapeutic option if high ICP is due to communicating external hydrocephalus. We aimed at describing the efficacy and safety of ELD used in a cohort of traumatic or non-traumatic brain-injured patients.

METHODS

In this multicentre retrospective analysis, patients had a delayed onset of high ICP after the initial injury and/or a poor response to ICP treatments. ELD was considered in the presence of radiological signs of communicating external hydrocephalus. Changes in ICP values and side effects following the ELD procedure were reported.

RESULTS

Thirty-three patients with a median age of 51 years (25-75th percentile: 34-61 years) were admitted after traumatic (n = 22) or non-traumatic (n = 11) brain injuries. Their initial Glasgow Coma Scale score was 8 (4-11). Eight patients underwent external ventricular drainage prior to ELD. Median time to ELD insertion was 5 days (4-8) after brain insult. In all patients, ELD was dramatically effective in lowering ICP: 25 mmHg (20-31) before versus 7 mmHg (3-10) after (p < 0.001). None of the patients showed adverse effects such as pupil changes or intracranial bleeding after the procedure. One patient developed an ELD-related infection.

CONCLUSIONS

These findings indicate that ELD may be considered potentially effective in controlling ICP, remaining safe if a firm diagnosis of communicating external hydrocephalus has been made.

Factors associated with shunt-dependent hydrocephalus after decompressive craniectomy for traumatic brain injury

OBJECTIVE Posttraumatic hydrocephalus (PTH) affects 11.9%-36% of patients undergoing decompressive craniectomy (DC) and is an important cause of morbidity after traumatic brain injury (TBI). Early diagnosis and treatment of PTH can prevent further neurological compromise in patients who are recovering from TBI. There is limited data on predictors of shunting for PTH after DC for TBI. METHODS Prospectively collected data from the erythropoietin severe TBI randomized controlled trial were studied. Demographic, clinical, and imaging data were analyzed for enrolled patients who underwent a DC. All head CT scans during admission were reviewed and assessed for PTH by the Gudeman criteria or the modified Frontal Horn Index ≥ 33%. The presence of subdural hygromas was categorized as unilateral/bilateral hemispheric or interhemispheric. Using L1-regularized logistic regression to select variables, a multiple logistic regression model was created with ventriculoperitoneal shunting as the binary outcome. Statistical significance was set at p < 0.05. RESULTS A total of 60 patients who underwent DC were studied. Fifteen patients (25%) underwent placement of a ventriculoperitoneal shunt for PTH. The majority of patients underwent unilateral decompressive hemicraniectomy (n = 46, 77%). Seven patients (12%) underwent bifrontal DC. Unilateral and bilateral hemispheric hygromas were noted in 31 (52%) and 7 (11%) patients, respectively. Interhemispheric hygromas were observed in 19 patients (32%). The mean duration from injury to first CT scan showing hemispheric subdural hygroma and interhemispheric hygroma was 7.9 ± 6.5 days and 14.9 ± 11.7 days, respectively. The median duration from injury to shunt placement was 43.7 days. Multivariate analysis showed that the presence of interhemispheric hygroma (OR 63.6, p = 0.001) and younger age (OR 0.78, p = 0.009) were significantly associated with the need for a shunt after DC. CONCLUSIONS The presence of interhemispheric subdural hygromas and younger age were associated with shunt-dependent hydrocephalus after DC in patients with severe TBI.

Adult posthaemorrhagic hydrocephalus animal models

Posthaemorrhagic hydrocephalus (PHH) is often associated with high morbidity and mortality and serves as an important clinical predictor of poor outcomes after intracranial haemorrhage (ICH). We are lack of effective medical intervention methods to improve functional outcomes in patients with PHH because little is still known about the mechanisms of PHH pathogenesis. Animal models play a key role in the study of PHH. Developed a suitable animal model that will help us to be better to find preventative strategies and improve the prognosis of patients with PHH. The purpose of this review is to summarize the body of knowledge gained from animal studies.

Cerebrospinal fluid dynamics study in communicating hydrocephalus

Context:

Communicating hydrocephalus often poses a challenge in diagnosis and management decisions.

Aims:

The objective of this study is to measure the opening pressure (P_o), pressure volume index (PVI), and cerebrospinal fluid outflow resistance (R_out), in patients with communicating hydrocephalus using bolus lumbar injection method and to evaluate its diagnostic and prognostic value.

Materials and Methods:

The study was conducted in 50 patients with communicating hydrocephalus, including normal pressure hydrocephalus (NPH) (19), post-meningitic hydrocephalus (23) and post-traumatic hydrocephalus (8). An improvised bolus lumbar injection method [the Madras Institute of Neurology (MIN) method] was used.

Results:

In the NPH Group, the CSF dynamics studies correlated well with the clinico-radiological classification. The prediction of shunt responsiveness by CSF dynamics studies correlated with good outcome in 87.5%. In the post-meningitic hydrocephalus group, the value of CSF dynamics studies in predicting patients needing shunt was 89.5%. The CSF dynamics studies detected patients who needed shunt earlier than clinical or radiological indications. In the post-traumatic hydrocephalus group, 62.5% of patients improved with the treatment based on CSF dynamics studies.

Conclusions:

The improvised bolus lumbar injection method (MIN method) is a very simple test with fairly reliable and reproducible results. Study of CSF dynamics is a valuable tool in communicating hydrocephalus for confirmation of diagnosis and predicting shunt responsiveness. This is the first time that the value of CSF dynamics has been studied in patients with post-meningitic hydrocephalus. It was also useful for early selection of cases for shunting and for identifying patients with atrophic ventriculomegaly, thereby avoiding unnecessary shunt.

The Association Between Ventriculo-Peritoneal Shunt and Acute Appendicitis in Patients with Traumatic Brain Injury: A 14-Year, Population-Based Study

OBJECTIVE

The association between preexisting ventriculoperitoneal (VP) shunt and the risk of new-onset acute appendicitis in patients with traumatic brain injury (TBI) is not well established. The aim of the present study was to determine the relationships between VP shunt and acute appendicitis in patients with TBI.

METHODS

A longitudinal cohort study matched by a propensity score in patients with TBI with (4781 patients) or without (9562 patients) VP shunt was conducted using the National Health Insurance Research Database in Taiwan between January 1993 and December 2013.

RESULTS

The main outcome studied was diagnosis of acute appendicitis. The cumulative probability of acute appendicitis was not different between these 2 groups (P = 0.6244). A Cox model showed central nervous system (CNS) infection to be an independent predictor of acute appendicitis with an adjusted hazard ratio of 2.98. Patients with TBI with both a VP shunt and a CNS infection had a greater risk of developing new-onset acute appendicitis (hazard ratio 4.25; 95% confidence interval 1.84-9.81) compared patients with TBI without a VP shunt or CNS infection.

CONCLUSIONS

We concluded that VP shunt is not a risk factor in the development of appendicitis in patients with TBI. Patients with TBI with a shunt and a CNS infection may have a greater risk of developing acute appendicitis. Therefore, care in avoiding CNS infection is a key for the prevention acute appendicitis in this patient population.

Revisiting secondary normal pressure hydrocephalus: does it exist? A review

OBJECTIVE There are several etiologies that can lead to the development of secondary normal pressure hydrocephalus (sNPH). The aim of this study was to evaluate the etiology, diagnosis, treatment, and outcome in patients with sNPH and to highlight important differences between the separate etiologies. METHODS A comprehensive review of the literature was performed to identify studies conducted between 1965 and 2015 that included data regarding the etiology, treatment, diagnosis, and outcome in patients with sNPH. Sixty-four studies with a total of 1309 patients were included. The inclusion criteria of this study were articles that were written in English, included more than 2 patients with the diagnosis of sNPH, and contained data regarding the etiology, diagnosis, treatment, or outcome of NPH. The most common assessment of clinical improvement was based on the Stein and Langfitt grading scale or equivalent improvement on other alternative ordinal grading scales. RESULTS The main etiologies of sNPH were subarachnoid hemorrhage (SAH) in 46.5%, head trauma in 29%, intracranial malignancies in 6.2%, meningoencephalitis in 5%, and cerebrovascular disease in 4.5% of patients. In 71.9% of patients the sNPH was treated with ventriculoperitoneal shunt placement, and 24.4% had placement of a ventriculoatrial shunt. Clinical improvement after shunt placement was reported in 74.4% and excellent clinical improvement in 58% of patients with sNPH. The mean follow-up period after shunt placement was 13 months. Improvement was seen in 84.2% of patients with SAH, 83% of patients with head trauma, 86.4% of patients with brain tumors, 75% of patients with meningoencephalitis, and 64.7% of patients with NPH secondary to stroke. CONCLUSIONS Secondary NPH encompasses a diverse group of clinical manifestations associated with a subset of patients with acquired hydrocephalus. The most common etiologies of sNPH include SAH and traumatic brain injury. Secondary NPH does indeed exist, and should be differentiated from idiopathic NPH based on outcome and on clinical, pathophysiological, and epidemiological characteristics, but should not be considered as a separate entity.