Ventricular Drainage Research Articles

Conical drill bit for optimized external ventricular drain placement: a proof-of-concept study.

Despite external ventricular drain (EVD) procedures being commonplace in neurosurgical practice, suboptimal placement rates remain high, and complications are not uncommon. The angle of the EVD catheter insertion and the accuracy of the drill hole placement are major factors determining successful EVD placement that are dependent on the drill bit morphology. The standard cylindrical 2-fluted twist drill bit creates a relatively deep and narrow drill hole that requires precise positioning, has limited visibility of the drill hole bottom and restricted catheter angular adjustment range, and poses the risk of inadvertent dural puncture. To overcome the standard problems associated with EVD drill bit morphology, the authors propose novel cone-shaped drill bits for EVD placement. Conical drill bits of 30° and 45° were designed, manufactured, and tested in a simulated laboratory setting as well as in three human cadavers with intact skull, dura mater, and brain. Drill bit performance was rated by neurosurgical trainees across various domains using Likert scale-type questions. In the laboratory, maximum drilling temperatures adjacent to the drill hole were recorded and compared for the standard drill bit and the 30° and 45° conical drill bits and were not significantly different (p = 0.631 and p = 0.326, respectively). The maximum temperature recorded directly underneath the drilling site for the 45° drill bit was significantly higher than the temperature of the standard drill bit (p = 0.043). The differences between the standard and 30° drill bits were not significant (p = 0.783). Upon cadaver testing, the drilling times with 30° and 45° conical drill bits were significantly longer than those with the standard drill bit (p = 0.036 and p = 0.002, respectively). Likert scale scores were significantly higher for the conical 30° (median [IQR] 4.7 [3.3-5]) and 45° (4 [2-5]) drill bits than for the standard drill bit (1.7 [1-2.5], p < 0.0001), indicating significantly better performance. Conical drill bits used as a "rescue" strategy allowed for an EVD catheter angular adjustment range 6 to 9 times greater than that for the standard drill bit and resulted in a zero inadvertent dural puncture rate. The 30° conical drill bit can be safely used on its own or as a rescue tool to potentially achieve improved confidence, visualization, targeting, and precision of EVD placement while essentially eliminating the possibility of unintentional dural puncture with minimal increase in the total procedure time.

Suspected medullary washout leading to severe polyuria following delayed cerebral ischemia: a case report

BackgroundDelayed cerebral ischemia is a clinical entity commonly encountered in patients presenting with acute neurological injury and is often complicated by dysnatremias, such as the cerebral salt wasting syndrome. In this case report, we described an exceptional case of polyuria attributed to an initial cerebral salt wasting phenomenon and iatrogenic-induced medullary washout.Case presentationA 53-year-old woman was admitted to our hospital for the management of a Modified Fisher scale grade 4 subarachnoid hemorrhage due to a ruptured posterior communicating aneurysm. She was initially managed with coil embolization and external ventricular drain due to secondary hydrocephalus. Throughout the course of her hospitalization, she developed severe polyuria reaching up to 40L per day. To keep up with the excessive urinary losses and maintain appropriate cerebral perfusion, fluid replacement therapy was adjusted every hour, reaching up to 1.3 L of crystalloid per hour in addition to aminergic support. An initial diagnosis of partial diabetes insipidus, followed by a cerebral salt wasting syndrome was suspected. While the urine output continued to increase, her serum urea concentration progressively decreased to a point of almost being undetectable on day 9. At that time, the presence of an interstitial medulla washout was hypothesized. Various pharmacological and non-pharmacological interventions were progressively introduced to regain normal renal homeostasis, including non-steroidal anti-inflammatory drugs, fludrocortisone, oral urea and high-protein intake. Medications were progressively weaned, and the patient was successfully discharged from the ICU.ConclusionsCerebral salt wasting should be considered in the initial differential diagnosis of a patient presenting with polyuria in the context of acute neurological injury. Early recognition of this entity is critical to quickly implement proper management. However, as shown in this case report, the concomitance of delayed cerebral ischemia may complexify that management.

Accuracy, Hemorrhagic Complications and CT Radiation Dose of Emergency External Ventricular Drain (EVD) Placement in Pediatric Patients: A 15-Year Retrospective Analysis.

To assess accuracy, the frequency of hemorrhagic complications and computed tomography (CT) radiation dose parameters in pediatric patients undergoing landmark-guided external ventricular drain (EVD) placement in an emergency setting. Retrospective analysis comprised 36 EVD placements with subsequent CT control scans in 29 patients (aged 0 to 17 years) in our university hospital from 2008 to 2022. The position of the EVD as well as the presence and extension of bleeding were classified according to previously established grading schemes. Dose length product (DLP), volume-weighted CT dose index (CTDIvol) and scan length were extracted from the radiation dose reports and compared to the diagnostic reference values (DRLs) issued by the German Federal Office for Radiation Protection. After the initial EVD placement, optimal positioning of the catheter tip into the ipsilateral frontal horn or third ventricle (Grade I), or a functional positioning in the contralateral lateral ventricle or the non-eloquent cortex (Grade II), was achieved in 28 and 8 cases, respectively. In 32 of 36 procedures, no evidence of hemorrhage was present in the control CT scan. Grade 1 (<1 mL) and Grade 2 (≥1 to 15 mL) bleedings were detected after 3 and 1 placement(s), respectively. For control scans after EVD placements, CTDIvol (median [25%; 75% quartile]) was 39.92 [30.80; 45.55] mGy, DLP yielded 475.50 [375.00; 624.75] mGy*cm and the scan length result was 136 [120; 166] mm. Exceedances of the DRL values were observed in 14.5% for CTDIvol, 12.7% for DLP and 65.6% for the scan length. None of these values was in the range requiring a report to the national authorities. Landmark-based emergency EVD placement in pediatric patients yielded an optimal position in most cases already after the initial insertion. Complications in terms of secondary hemorrhages are rare. CT dose levels associated with the intervention are below the reportable threshold of the national DRLs in Germany.

Investigation of risk factors for external ventricular drainage‑associated central nervous system infections in patients undergoing neurosurgery.

Meningitis/ventriculitis (MV) is an illness which can occur as a complication following neurosurgical procedures. Devices such as an external ventricular drain (EVD) are also related to considerable complications, such as infections. The present study examined the risk factors associated with central nervous system (CNS) infections associated with the external ventricle drainage system. The present retrospective study included all patients hospitalized between April, 2011 and August, 2018 who had been receiving therapy with EVD for developed hydrocephalus. A total of 48 out of 65 patients were classified into two groups as follows: Patients without MV (group A) and patients who developed MV (group B). The durations of hospital stay and intensive care unit (ICU) stay were significantly lower in group A (32.4±24 and 21.1±11 days, respectively) compared to group B (54.7±37 and 42±24 days, respectively) (P=0.027 and P=0.001, respectively). The Acute Physiological and Chronic Health Evaluation II (APACHE II) score and EVD distance from the wound exit side to the burr hole were significantly lower in the survivors compared to the non-survivors (17.5±6 and 15.4±4 vs. 22.5±6 and 39.8±38, respectively). Receiver operating characteristic analysis revealed that the APACHE II score with an area under the curve [(AUC) of 0.677, P=0.044, and 95% confidence interval (CI) of (0.516-0.839)] and a cut-off value of 14 could predict mortality with a sensitivity of 100% and a specificity of 71%; the EVD distance from the wound exit side from the burr hole with an AUC of 0.694 (P=0.028), 95% CI of 0.521-0.866 and a cut-off value of 11.5 mm could predict mortality with a sensitivity of 88% and a specificity of 83%. On the whole, the present study demonstrates that the EVD-related distance from the wound exit side of the burr hole can predict poor outcomes due to CNS infections in patients undergoing neurosurgery.

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.

Critical Care Experience With Clinical Cerebral Autoregulation Testing in Adults With Traumatic Brain Injury.

To describe the setting, feasibility, and safety of static cerebral autoregulation testing in critically injured adults with traumatic brain injury (TBI). Methods: We reviewed static autoregulation testing using transcranial Doppler (TCD) ultrasound in patients > 18 years with TBI ICD codes between January 1, 2014, and December 31, 2021. Adverse events during testing were defined as systemic hypertension (systolic blood pressure (SBP>180 mmHg), bradycardia (HR<40 bpm), and high ICP (>30 mmHg). Impaired and absent cerebral autoregulation was defined as an autoregulatory index (ARI) <0.4 and ARI 0, respectively. We characterized prescribed changes in intracranial pressure (ICP) and cerebral perfusion pressure (CPP) targets by autoregulation testing results. Results: A total of 135 patients, median age 31 (interquartile range (IQR) 24, 43) years, 71.9% male, admission Glasgow coma scale (GCS) score 3 (IQR 3, 5.5), and 70.9% with subdural hematoma from severe (GCS 3-8; 133 (98.5%)) and moderate (GCS 9-12; 2 (1.5%)) TBI, underwent 309 attempted testing. All patients were mechanically ventilated and had ICP monitoring; 246 (80%) had brain tissue oxygen monitoring, and 68 (22%) had an external ventricular drain. The median number of autoregulation tests was two (range 1-3) tests/patient, and the median admission to the first test time was two days (IQR 1, 3). Of 55 (17.8%) tests not completed, systemic hypertension (32, 10.4%), intracranial hypertension (10, 3.2%), and bradycardia (3, 0.9%) were transient. Fifty-three (51%) of the first (n=104) autoregulation tests showed impaired/absent cerebral autoregulation. Impaired/absent autoregulation results at the first test were associated with repeat cerebral autoregulation testing (RR 2.25, 95% CI [1.40-3.60], p=0.0007) than intact cerebral autoregulation results. Pre-testing cerebral hemodynamic targets were maintained (n=131; 86.8%) when cerebral autoregulation was impaired (n=151; RR 1.49, 95% CI [1.25-1.77], p<0.0001). However, 15 (9.9%) test results led to higher ICP targets (from 20 mmHg to 25 mmHg), 5 (3.3%) results led to an increase in CPP target (from 60 mmHg to 70 mmHg), and five out of 131 (3.8%) patients underwent decompressive craniectomy and placement of an external ventricular drain. Intact cerebral autoregulation results (n=43/103, 41.7%) were associated with a change in ICP targets from 20 mmHg to 25 mmHg (RR 3.15, 95% CI [1.97-5.03], p<0.0001). Conclusions: Static cerebral autoregulation testing was feasible, safe, and useful in individualizing the care of patients with moderate-severe TBI receiving multimodal neuromonitoring. Testing results guided future testing, cerebral hemodynamic targets, and procedural decisions. Impaired cerebral autoregulation was very common.

Tunneled antibiotic-impregnated vs. bolt-connected, non-coated external ventricular drainage: a comparison of complications.

External ventricular drainage (EVD) is a common emergency neurosurgical procedure, but it is not free of adverse events. The aim of this study is to compare the complication rate of two frequently used EVD types, namely, tunneled antibiotic-impregnated catheters (Bactiseal©) and bolt-connected non-coated devices (Camino©). All EVDs placed between 1 March 2015 and 31 December 2017 were registered. Procedures performed with any catheter different from Bactiseal© or Camino© EVD with incomplete follow-up and those EVDs placed due to infectious disease were excluded. Demographic and clinical variables, as well as the overall complication rate (infection, hemorrhage, obstruction, malposition of the catheter, and involuntary pull-out of the device) and the need for replacement of the EVD, were collected. A total of 77 EVDs were finally considered for analysis (40 Bactiseal® and 37 Camino®). There was a statistically significant difference in diagnosis and also in the location of the procedure, as more bolt-connected EVD was placed outside the operating room (97.3 vs. 23.5%, p < 0.001) due to emergent pathologies such as vascular diseases and spontaneous hemorrhages. In the univariate analysis, a statistically significantly higher rate of catheter involuntary pull-out (29.7 vs. 7.5%, p = 0.012) and the need for EVD replacement (32.4 vs. 12.5%, p = 0.035) was found in the Camino cohort. However, those differences could not be confirmed with multivariable analysis, which showed no association between the type of catheter and any of the studied complications. Ventriculostomy duration was identified as a risk factor for infection (OR 1.09, 95% CI 1.02-1.18). No significant differences were observed regarding infection, hemorrhage, obstruction, malposition, involuntary catheter pull-out, and the need for EVD replacement when comparing non-impregnated bolt-connected EVDs (Camino®) with tunneled antibiotic-impregnated catheters (Bactiseal®). The duration of EVD was associated with an increased risk of infection.

Delayed Intracerebral Hematoma after Ventriculoperitoneal Shunt in the Context of Ruptured Brain Arteriovenous Malformation: A Literature Review.

Hemorrhagic complications arising from ventricular drainage procedures are typically asymptomatic and of low volume. A particular subset of these complications, known as delayed intracranial hemorrhage (DICH), is however recognized for its particularly poor prognosis. We primarily aimed to identify epidemiological characteristics associated with DICH, to shed light on its occurrence and potential risk factors. To do so, we performed a retrospective analysis of a series of ten patients who presented with DICH in the context of a ruptured brain arteriovenous malformation (bAVM) and a systematic literature review of all DICH cases reported in the literature. Our ten patients showed delayed neurological deterioration after a ventriculoperitoneal shunt (VPS) procedure, with a computed tomography (CT) scan revealing a DICH surrounding the ventricular catheter, distinct and away from the nidus of their previously ruptured bAVM. Four patients (40%) rapidly declined and passed away, three (30%) required surgical management and the remaining three (30%) demonstrated gradual clinical improvement with conservative management. In the literature, most patients presenting with DICH had hydrocephalus associated with neurovascular disorders (47% of cases), such as bAVM rupture in our present series. These constatations point out the significance of the underlying pathologies potentially being predisposed to these unusual complications.

Simulation Method for the Physical Deformation of a Three-Dimensional Soft Body in Augmented Reality-Based External Ventricular Drainage.

Intraoperative navigation reduces the risk of major complications and increases the likelihood of optimal surgical outcomes. This paper presents an augmented reality (AR)-based simulation technique for ventriculostomy that visualizes brain deformations caused by the movements of a surgical instrument in a three-dimensional brain model. This is achieved by utilizing a position-based dynamics (PBD) physical deformation method on a preoperative brain image. An infrared camera-based AR surgical environment aligns the real-world space with a virtual space and tracks the surgical instruments. For a realistic representation and reduced simulation computation load, a hybrid geometric model is employed, which combines a high-resolution mesh model and a multiresolution tetrahedron model. Collision handling is executed when a collision between the brain and surgical instrument is detected. Constraints are used to preserve the properties of the soft body and ensure stable deformation. The experiment was conducted once in a phantom environment and once in an actual surgical environment. The tasks of inserting the surgical instrument into the ventricle using only the navigation information presented through the smart glasses and verifying the drainage of cerebrospinal fluid were evaluated. These tasks were successfully completed, as indicated by the drainage, and the deformation simulation speed averaged 18.78 fps. This experiment confirmed that the AR-based method for external ventricular drain surgery was beneficial to clinicians.

Intracranial Arachnoiditis and Hydrocephalus

A 62-year-old man presented a diffuse and predominantly cisternal acute nonaneurysmal subarachnoid hemorrhage associated with hydrocephalus. An external ventricular drain was placed, followed by clinical deterioration after its removal. At this point, a heavily T2-weighted high-resolution sequence of a brain magnetic resonance imaging showed acute hydrocephalus recrudescence and multiple arachnoid adhesions in the supravermian and interpeduncular cisterns, creating a loculated/cystic appearance. The diagnosis of intracranial arachnoiditis was made. Intracranial arachnoiditis results from meningeal inflammation. Fibrosis and adhesions at the subarachnoid spaces may follow, restricting cerebrospinal fluid circulation, particularly at the cranial base. Hydrocephalus probably resulted from the combination of subarachnoid hemorrhage and extensive scaring at the basal cisterns, precluding transdural and transvenous cerebrospinal fluid efflux. Heavily T2-weighted high-resolution magnetic resonance imaging sequences allow an exquisite depiction of arachnoiditis, displaying obstructive cisternal membranes, and contribute to better etiologic assessment and management of hydrocephalus.

Ventriculostomy Associated with Reduced Mortality in Severe Traumatic Brain Injury Compared to Parenchymal ICP Monitoring: A Propensity Score–Adjusted Analysis

There is a lack of data on whether intracranial pressure (ICP)-guided therapy with an intraparenchymal fiberoptic monitor (IPM) or an external ventricular drain (EVD) leads to superior outcomes. Our goal is to determine the relationship between ICP-guided therapy with an EVD or IPM and mortality. Retrospective analysis of severe traumatic brain injury cases that required IPM or EVD placement for ICP-guided therapy from January 1, 2010 to December 31, 2020. The data were obtained from the Pennsylvania Trauma Systems Foundation registry. A total of 2305 patients met the inclusion criteria, with 1048 (45.5%) IPM and 1257 (54.5%) EVD placed. Inpatient mortality occurred in 337 (32.2%) and 334 (26.6%) patients in the IPM and EVD cohorts, respectively (P= 0.003). Even among those treated medically only, inpatient mortality occurred in 171 (30.8%) of those with an IPM and in 100 (23.4%) of those with an EVD (P= 0.010). Multivariable logistic regression analysis showed that older age (odds ratio [OR] 1.03, P < 0.001), lower Glasgow Coma Scale (GCS) score (OR 1.16, P < 0.001), requiring surgery (OR 1.22, P= 0.049), and an IPM (OR 1.40, P= 0.001) were significant predictors of mortality. Propensity score-adjusted analysis using inverse probability of treatment weighted method revealed a 28% decrease in mortality and a 14% decrease in length of hospital stay with EVD use when adjusting for age, sex, GCS, Injury Severity Score, surgery, and Hispanic ethnicity. A significant mortality benefit was associated with the use of EVD compared to IPM. This mortality benefit was observed regardless of whether patients required surgery or not.

Power Drill Craniostomy for Bedside Intracranial Access in Traumatic Brain Injury Patients.

Invasive neuromonitoring is a bedrock procedure in neurosurgery and neurocritical care. Intracranial hypertension is a recognized emergency that can potentially lead to herniation, ischemia, and neurological decline. Over 50,000 external ventricular drains (EVDs) are performed in the United States annually for traumatic brain injuries (TBI), tumors, cerebrovascular hemorrhaging, and other causes. The technical challenge of a bedside ventriculostomy and/or parenchymal monitor placement may be increased by complex craniofacial trauma or brain swelling, which will decrease the tolerance of brain parenchyma to applied procedural force during a craniostomy. Herein, we report on the implementation and safety of a disposable power drill for bedside neurosurgical practices compared with the manual twist drill that is the current gold standard. Mechanical testing of the drill's stop extension (n = 8) was conducted through a calibrated tensile tester, simulating an axial plunging of 22.68 kilogram (kg) or 50 pounds of force (lbf) and measuring the strength-responsive displacement. The mean displacement following compression was 0.18 ± 0.11 mm (range of 0.03 mm to 0.34 mm). An overall cost analysis was calculated based on the annual institutional pricing, with an estimated $64.90 per unit increase in the cost of the disposable electric drill. Power drill craniostomies were utilized in a total of 34 adult patients, with a median Glasgow Coma Scale (GCS) score of six. Twenty-seven patients were male, with a mean age of 50.7 years old. The two most common injury mechanisms were falls and motor vehicle/motorcycle accidents. EVDs were placed in all subjects, and additional quad-lumen neuromonitoring was applied to 23 patients, with no incidents of plunging events or malfunctions. One patient developed an intracranial infection and another had intraparenchymal tract hemorrhaging. Two illustrative TBI cases with concomitant craniofacial trauma were provided. The disposable power drill was successfully implemented as an option for bedside ventriculostomies and had an acceptable safety profile.

External Ventricular Drains versus Intraparenchymal Pressure Monitors in the Management of Moderate to Severe Traumatic Brain Injury: Experience at Two Academic Centers over a Decade

The choice between external ventricular drain (EVD) and intraparenchymal monitor (IPM) for managing intracranial pressure in moderate-to-severe traumatic brain injury (msTBI) patients remains controversial. This study aimed to investigate factors associated with receiving EVD versus IPM and to compare outcomes and clinical management between EVD and IPM patients. Adult msTBI patients at 2 similar academic institutions were identified. Logistic regression was performed to identify factors associated with receiving EVD versus IPM (model 1) and to compare EVD versus IPM in relation to patient outcomes after controlling for potential confounders (model 2), through odds ratios (ORs) and 95% confidence intervals (CIs). Of 521 patients, 167 (32.1%) had EVD and 354 (67.9%) had IPM. Mean age, sex, and Injury Severity Score were comparable between groups. Epidural hemorrhage (EDH) (OR 0.43, 95% CI 0.21-0.85), greater midline shift (OR 0.90, 95% CI 0.82-0.98), and the hospital with higher volume (OR 0.14, 95% CI 0.09-0.22) were independently associated with lower odds of receiving an EVD whereas patients needing a craniectomy were more likely to receive an EVD (OR 2.04, 95% CI 1.12-3.73). EVD patients received more intense medical treatment requiring hyperosmolar therapy compared to IPM patients (64.1% vs. 40.1%). No statistically significant differences were found in patient outcomes. While EDH, greater midline shift, and hospital with larger patient volume were associated with receiving an IPM, the need for a craniectomy was associated with receiving an EVD. EVD patients received different clinical management than IPM patients with no significant differences in patient outcomes.

External ventriculostomy-associated infection reduction after updating a care bundle

BackgroundDespite the clinical benefits of external ventricular drains (EVD), these devices can lead to EVD-related infections (EVDRI). The drainage insertion technique and standardized guidelines can significantly reduce the risk of infection, mainly caused by gram-positive bacteria. However, gram-negative microorganisms are the most frequent causative microorganisms of EVDRI in our hospital. We aimed to determine whether a new bundle of measures for the insertion and maintenance of a drain could reduce the incidence of EVDRI. This cohort study of consecutive patients requiring EVD from 01/01/2015 to 12/31/2018 compared the patients’ characteristics before and after introducing an updated protocol (UP) for EVD insertion and maintenance in 2017.ResultsFrom 204 consecutive patients, 198 requiring EVD insertion were included (54% females, mean age 55 ± 15 years). The before-UP protocol included 87 patients, and the after-UP protocol included 111 patients. Subarachnoid (42%) and intracerebral (24%) hemorrhage were the main diagnoses at admission. The incidence of EVDRI fell from 13.4 to 2.5 episodes per 1000 days of catheter use. Gram-negative bacteria were the most frequent causative microorganisms. Previous craniotomy remained the only independent risk factor for EVDRI. EVDRI patients had increased mechanical ventilation durations, hospital and ICU stays, and percutaneous tracheostomy requirements.ConclusionsA care bundle focusing on fewer catheter sampling and more accurate antiseptic measures can significantly decrease the incidence of EVDRI. After implementing the management protocol, a decreased incidence of infections caused by gram-negative and gram-positive bacteria and reduced ICU and hospital lengths of stay were observed.

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.

Augmented Reality-Assisted versus Freehand Ventriculostomy in a Head Model.

Ventriculostomy (VST) is a frequent neurosurgical procedure. Freehand catheter placement represents the standard current practice. However, multiple attempts are often required. We present augmented reality (AR) headset guided VST with in-house developed head models. We conducted a proof of concept study in which we tested AR-guided as well as freehand VST. Repeated AR punctures were conducted to investigate if a learning curve can be derived. Five custom-made 3D-printed head models, each holding an anatomically different ventricular system, were filled with agarose gel. Eleven surgeons placed two AR-guided as well as two freehand ventricular drains per head. A subgroup of four surgeons did a total of three series of AR-guided punctures each to test for a learning curve. A Microsoft HoloLens served as the hardware platform. The marker-based tracking did not require rigid head fixation. Catheter tip position was evaluated in computed tomography scans. Marker-tracking, image segmentation, and holographic display worked satisfactorily. In freehand VST, a success rate of 72.7% was achieved, which was higher than under AR guidance (68.2%, difference not statistically significant). Repeated AR-guided punctures increased the success rate from 65 to 95%. We assume a steep learning curve as repeated AR-guided punctures led to an increase in successful attempts. Overall user experience showed positive feedback. We achieved promising results that encourage the continued development and technical improvement. However, several more developmental steps have to be taken before an application in humans can be considered. In the future, AR headset-based holograms have the potential to serve as a compact navigational help inside and outside the operating room.

Bilateral vocal cord palsy as complication of CNS tuberculosis

BackgroundTuberculous meningitis, a rare but severe form of extrapulmonary tuberculosis, frequently affects cranial nerves. While nerves III, VI and VII are commonly involved, involvement of caudal cranial nerves is rarely described. Here, we report a rare case of bilateral vocal cord palsy secondary to caudal cranial nerve involvement in tuberculous meningoencephalitis, that occurred in Germany, a country with low tuberculosis incidence.Case presentationA 71-year-old woman was transferred for further treatment of hydrocephalus as a complication of presumed bacterial meningitis with unknown pathogen at that time. Because of decreased consciousness, intubation was performed and an empiric antibiotic therapy with ampicillin, ceftriaxone and acyclovir was initiated. Upon admission to our hospital, an external ventricular drainage was placed. Cerebrospinal fluid analysis revealed Mycobacterium tuberculosis as the causative pathogen, and antitubercular treatment was initiated. Extubation was possible one week after admission. Eleven days later, the patient developed inspiratory stridor that worsened within a few hours. Flexible endoscopic evaluation of swallowing (FEES) revealed new-onset bilateral vocal cord palsy as the cause of respiratory distress, which required re-intubation and tracheostomy. The bilateral vocal cord palsy persisted despite continued antitubercular therapy on the follow-up examination.ConclusionConsidering the aetiology of infectious meningitis, cranial nerve palsies may be suggestive for tuberculous meningitis as underlying disease given their rarity in other bacterial forms of meningitis. Nevertheless, intracranial involvement of inferior cranial nerves is rare even in this specific entity, as only extracranial lesions of inferior cranial nerves have been reported in tuberculosis. With this report of a rare case of bilateral vocal cord palsy due to intracranial involvement of the vagal nerves, we emphasize the importance of timely initiation of treatment for tuberculous meningitis. This may help to prevent serious complications and associated poor outcome since the response to anti-tuberculosis therapy may be limited.

Obstructive Infantile Hydrocephalus Secondary to Meningoventriculitis: A Case Report

Obstructive infantile hydrocephalus may arise due to anatomic or functional obstruction of cerebrospinal fluid flow. Obstruction of the aqueduct of sylvius (aqueductal stenosis) causes dilation of the lateral and third ventricles, while the size of the fourth ventricle remains relatively normal. Obstructive infantile hydrocephalus with meningoventriculitis is a rare phenomenon, and literature with only 2 other children with similar findings have been reported. We hereby report a case of a 16-week-old infant who developed Escherichia coli meningoventriculitis, later complicated by the development of hydrocephalus, challenging the management. The diagnosis was based on the magnetic resonance imaging of the brain, which showed hydrocephalus, and the cerebrospinal fluid culture showing Escherichia coli meningoventriculitis. The case was managed with serial ventricular drainage along with antibiotics followed by staged ventriculoperitoneal shunting. Serial measurement of head circumference is essential to prompt diagnostic suspicion in the case of paediatric meningitis.

Unilateral rete mirabile in multiple intracranial arteries with ipsilateral agenesis of the internal carotid artery: a case report

BackgroundRete mirabile of the cerebral artery is a rare anomaly, with most previous cases occurring in the middle cerebral artery or internal carotid artery. Here, we present the first report of unilateral rete mirabile in multiple intracranial arteries with ipsilateral internal carotid artery agenesis.Case presentationA 64-year-old Japanese woman was brought to the emergency department of our hospital in a deep coma. Computed tomography of the head showed severe intraventricular hemorrhage with subarachnoid hemorrhage. Computed tomography angiography showed not only congenital left internal carotid artery agenesis, but also rete mirabile of the left posterior communicating artery, the left posterior cerebral artery, and the left anterior cerebral artery. This unilateral vessel anomaly complex may have contributed to the formation of a peripheral aneurysm arising from a perforating branch of the pericallosal artery, which ruptured. The patient underwent urgent bilateral external ventricular drainage, but deteriorated and was declared brain dead.ConclusionsWe report the first case of unilateral rete mirabile in multiple intracranial arteries. Because the cerebral arteries in patients with rete mirabile may be vulnerable, close attention should be paid to the development of cerebral aneurysms.

Comparison of External Ventricular Drains with Ventricular Access Devices for the Emergency Management of Adult Hydrocephalus

We compared external ventricular drains (EVDs) with percutaneous continuous CSF drainage via ventricular access devices (VADs) for the acute management of hydrocephalus in adults. This was a retrospective review of all ventricular drains inserted for a new diagnosis of hydrocephalus into non-infected CSF over 4 years. We compared infection rates, return to theatre, and patient outcome between EVDs and VADs. We explored the effect of duration of drainage, frequency of sampling, hydrocephalus aetiology, and catheter location on these outcomes using multivariable logistic regression modelling. We included 179 drains (76 EVDs and 103 VADs). EVDs were associated with a higher rate of unplanned return to theatre for replacement or revision (27/76, 36%, vs 4/103, 4%, OR:13.4 95%CI:4.3-55.8). However, infection rates were higher in VADs (13/103, 13% vs 5/76, 7%, OR:2.0, 95%CI:0.65-7.7). EVDs were 91% antibiotic impregnated whereas VADs were 98% non-impregnated. In multivariable analysis, infection was associated with duration of drainage (median:11 days prior to infection for infected drains vs 7 days total for non-infected drains), but not drain type (VADs vs EVDs OR:1.6, 95%CI:0.5-6). EVDs had a higher rate of unplanned revisions but a lower infection rate compared to VADs. However, in multivariable analysis choice of drain type was not associated with infection. We suggest a prospective comparison of antibiotic impregnated VADs and EVDs using similar sampling protocols to assess whether VADs or EVDs for acute hydrocephalus have a lower overall complication rate.