Ipsilateral Frontal Horn Research Articles

The Device for Intraventricular Entry guide: a novel solution to a perpetual problem.

The authors designed a low-profile device for reliable ventricular access and prospectively studied its safety, efficacy, and accuracy at a large academic center. A novel device for ventricular entry, the Device for Intraventricular Entry (DIVE) guide, was designed and created by the first and senior authors. Fifty patients undergoing external ventricular drainage (EVD) or shunt placement were prospectively enrolled for DIVE-assisted catheter placement at a single academic center. The primary outcome was the catheter tip location on postprocedural CT. Secondary outcomes included number of catheter passes, clinically significant hemorrhages, and procedure-related infections. Fifty patients were enrolled. Indications included subarachnoid hemorrhage, intraventricular hemorrhage, traumatic brain injury, hydrocephalus, pseudotumor, and postsurgical wound drainage. In total, 76% (38/50) of patients underwent right-sided placement and 24% (12/50) underwent left-sided placement. All 100% (50/50) of patients had successful cannulation with an average of 1.06 passes. Postprocedural head CT confirmed ipsilateral frontal horn or third ventricle placement (Kakarla grade 1) in 92% (46/50) of patients and placement in the contralateral lateral ventricle in 8% (4/50) (Kakarla grade 2). There were no clinically significant track hemorrhages or procedural infections. This single-center prospective study investigated the safety and efficacy of DIVE-assisted ventricular access. In total, 100% of procedures had successful ventricular cannulation, with 92% achieving Kakarla grade 1, with an average of 1.06 passes without any clinical complications.

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.

768 The Device for Intraventricular Entry (DIVE) Guide: A Novel Solution to a Perpetual Problem

INTRODUCTION: Safe and reliable access to the ventricular system is a necessary skill in the neurosurgical armamentarium. The freehand technique for catheter placement remains an accepted method, yet the inaccuracy rate can be as high as 40%, with as many as 3 passes per procedure, and complication rates between 10-40%. A number of devices have been developed to assist with catheter placement, however, these devices inhibit ergonomics or require larger incisions and expensive navigation technology. METHODS: A novel device for ventricular entry, the DIVE guide, was designed by the first and senior author. 50 patients undergoing extra ventricular drain (EVD) or shunt placement were prospectively enrolled for DIVE assisted catheter placement under an IRB approved study with a non-significant risk (NSR) device designation. The primary outcome is catheter location on CT. Secondary outcomes include number of catheter passes, clinically significant hemorrhages and procedure-related infections. RESULTS: 50 patients were enrolled at a single academic center for ventricular access with DIVE assistance. Indications included subarachnoid or intraventricular hemorrhage, TBI, hydrocephalus, pseudotumor and post-surgical wound drainage. 76% (38/50) underwent right sided placement and 24% (12/20) underwent left. 100% (50/50) had successful cannulation in an average of 1.06 passes. Post procedure head CT confirmed ipsilateral frontal horn or 3rd ventricle placement (Kakarla Grade 1) in 92% (46/50) and 8% (4/50) in the contralateral lateral ventricle (Grade 2). There were no significant tract hemorrhages or procedural infections. CONCLUSIONS: This a prospective study to investigate the safety and efficacy of DIVE-assisted ventricular access. 100% of procedures had successful ventricular cannulation, with 92% achieving Kakarla Grade 1, in an average of 1.06 passes.

Orthogonal external ventricular drain (EVD) trajectory from burr holes sited by junior neurosurgical staff is superior to freehand placement: An in-silico model

External ventricular drain (EVD) or ventriculostomy placement is one of the most common neurosurgical procedures performed worldwide and is associated with complications including haemorrhage, malposition and infection. Several authors have attempted to define an ideal trajectory for placement, and scalp-mounted guidance devices have been devised to exploit the theoretical ideal orthogonal trajectory from the scalp to the lateral ventricles. However, uptake has been limited due to lack of demonstrated superiority to freehand placement. Previous modelling studies have failed to include a true-to-life sample of patients undergoing EVD insertion and excluded cases with midline shift or non-hydrocephalus indications. Further, none have attempted to model the orthogonal insertion of EVD via actual burr holes placed by junior neurosurgical staff. In our report of 58 cases of frontal EVD insertion in a low-volume Australian neurosurgical unit freehand EVD insertion resulted in acceptable placement in the ipsilateral frontal horn in 62% of cases, any ventricle in 22%, and in eloquent or non-eloquent brain in 16% of cases. The modelled orthogonal trajectory from the same burr holes, using post-procedural computed tomography scans and the S8 Stealth Station (Medtronic), resulted in superior placement; 80% in the ipsilateral frontal horn and 20% contralateral (p = 0.007). There were no significant malpositions associated with the modelled trajectories. In our series, 18% of freehand catheters required multiple placement attempts. In conclusion, our data suggests that an orthogonal trajectory may result in improved EVD positioning compared to freehand placement.

Effectiveness of a Standardized External Ventricular Drain Placement Protocol for Infection Control

Placement of an external ventricular drain (EVD) is a common procedure routinely completed at bedside by neurosurgical residents. A standardized protocol for placement and maintenance of an EVD is potentially useful. This single-institution retrospective review analyzed all patients who underwent placement of an EVD over a 5-year span using a standardized protocol. A total of 428 EVDs in 381 patients were placed as per this protocol. Overall compliance with the practice protocol was 98.7%. Overall, our infection rate was 1.86% (8 external ventricular drain-related infection [ERIs] over 428 EVDs). There was no difference in age for the ERI cases (median 55, range (50.5-60.5), compared with the non-ERI cases (median of 53, range [38-65]) (P= 0.512). Indications for placement of EVD were hemorrhage (51.9%, n= 198), tumor (16.2%, n= 62), trauma (12.8%, n= 49), hydrocephalus (11.5%, n= 44), cerebellar stroke (2.8%, n= 11), infection (3.1%, n= 12), unknown (1.3%, n= 5). Most EVDs (77.6%, n= 296) were placed bedside by second-year residents (median PGY level 2, interquartile range 1-2.75). Computed tomography confirmed placement in the ipsilateral frontal horn in 72% (n= 277) of EVDs. EVD-related complications were noted in 8.3% of EVDs (n= 32, with 8 infections and 24 tract hemorrhages). The median EVD duration was 10 days; duration of EVD had no statistically significant impact on the risk of an ERI (P= 1). Only replacement of an EVD was associated with an increased risk of infection. Adherence to a standard EVD placement protocol is useful in maintaining a low risk of ERI regardless of the duration of catheter utilization. Replacement of the catheter through the same access hole as the original catheter is associated with an increased risk of ERI.

A simple and cost-effective model for ventricular catheter placement training: technical note.

External ventricular drain (EVD) placement is one of first cranial procedures neurosurgery residents are expected to perform independently. While proper training improves patient outcomes, there are few options for practicing EVD placement prior to placing the EVD in patients in a clinical setting. Proposed solutions to this include using cadaveric models and virtual simulations, but barriers exist with these as well in regard to authenticity. EVD simulators using virtual reality technologies are a promising new technique for training, but the cost of these devices poses a barrier to general/widespread accessibility among smaller programs or underserved hospitals. The authors desribe a novel, yet simple, and cost-effective technique (less than $5 per mold) for developing a brain model constructed of homemade ballistics gelatin that can be used for teaching and practicing the placement of EVD. A brain model is made with ballistics gelatin using an anatomically correct skull model as a mold. A 3D-printed ventricular system model is used to create a mold of an anatomically correct ventricular system in the brain model. A group of medical students (n = 10) were given a basic presentation about EVD placement, including standard landmarks and placement techniques, and were also shown a demonstration of EVD placement on the brain model. They were then allowed to perform an EVD placement using the brain model. The students were surveyed on their experience with using the brain model, including usability and practicality of the model. Accuracy of EVD placement by each student was also assessed, with adequate position of catheter tip being in the ipsilateral frontal horn. The final product is fairly inexpensive and easy to make. It is soft enough to pass a catheter through, but it is also firm enough to maintain its shape, including a cavity representing the lateral ventricles. The dense gelatin holds the catheter in its final resting position, while the two halves are separated and inspected. All participants in the test group of medical students reported that the brain model was easy to use, helped them understand the steps and technique of EVD placement, and provided good feedback on the ideal position of ventricular catheters. All of the participants in the group had adequate positioning of their ventricular catheters after one attempt. The presented brain model is easy to replicate, inexpensive, anatomically accurate, and provides a medium for neurosurgeons to teach and practice ventricular catheter placement in a risk-free environment.

The importance of aspirin, catheterization accuracy, and catheter design in external ventricular drainage-related hemorrhage: a multicenter study of 1002 procedures.

External ventricular drainage (EVD) is the commonest neurosurgical procedure performed in daily neurosurgical practice, but relatively few studies have investigated the incidence and risk factors of its related hemorrhagic complications. This was a multicenter retrospective review of consecutive EVD procedures. Patients 18years or older who underwent EVD and had aroutine postoperative computed tomography (CT) scan performed within 24hours were included. EVD-related hemorrhage was defined as new intracranial hemorrhage immediately adjacent or within the ventricular catheter trajectory. The volume of hemorrhage and the position of the catheter tip were assessed. A review of patient-, disease-, and surgery-related factors including the ventricular catheter design utilized was conducted. The Bonferroni correction was applied to the alpha level of significance (0.05) for multivariable analysis. Nine hundred sixty-two patients underwent 1002 EVD performed by neurosurgeons in the operating theater. Sixteen percent (154) of patients were on aspirin before the procedure. Thirty-four percent (333) of patients had intracerebral hemorrhage, 25% (251) had aneurysmal subarachnoid hemorrhage and 16% (158) had traumatic brain injury. The mean duration from EVD to the first postoperative CT scan was 20 ± 4h. EVD-related hematomas were detected after 81 procedures with a per-catheter risk of 8.1%. Mean hematoma volume was 1.2 ± 3.3ml. Most were less than 1ml (grade I, 79%, 64), 1 to 15ml (grade II) in 20% (16) and a single clot larger than 15ml (grade III, 1%) were detected. Clinically significant hemorrhage that resulted in catheter occlusion occurred in 1.7% (17) of procedures. Most catheters (62%, 625) were optimally placed, i.e., its tip being within the ipsilateral frontal horn or third ventricle. Three non-antibiotic-impregnatedventricular catheter designs were used with 55% (550) being the 2.2-mm Integra™ catheter, 14% (137) being the 2.8-mm Medtronic™ catheter, and 31% (315) being the 3.1-mm Codman™ catheter. Independent significant predictors for EVD-related hemorrhage were the preoperative prescription of aspirin (adjusted OR 1.94; 95% CI 1.10-3.44), catheter malposition (aOR 1.99; 95% CI 1.22-3.23), and use of the 2.8-mm Medtronic™ catheter (aOR 4.22; 95% CI 2.39-7.41). The per-catheter risk of hemorrhage was 8.1%, but the incidence of symptomatic hemorrhage was low. The only patient risk factor was aspirin intake. This is the first study to evaluate and establish an association between catheter malposition and catheter design with EVD-related hemorrhage.

Safety, Accuracy, and Cost Effectiveness of Bedside Bolt External Ventricular Drains (EVDs) in Comparison with Tunneled EVDs Inserted in Theaters

External ventricular drain (EVD) placement is required frequently in neurosurgical patients to divert cerebrospinal fluid and monitor intracranial pressure. The usual practice is the tunneled EVD technique performed in operating theaters. EVD insertion through a bolt in intensive care also is described. We employ both practices in our institute. Herein, we compare the indications, accuracy, safety, and costs of the 2 techniques. This was a retrospective cohort study of a prospectively maintained EVD database of all patients undergoing first frontal EVD placement between January 2010 and December 2015. Those patients with preceding cerebrospinal fluid infection were excluded. We compared bolt EVD with tunneled EVD techniques in terms of accuracy of EVD tip location by analyzing computed tomography scans to grade catheter tip location as optimal (ipsilateral frontal horn) or otherwise suboptimal, and complications that include infection and revision rates. In total, 579 eligible patients aged 3 months to 84 years were identified; 430 had tunneled EVDs and 149 bolt EVDs. The most frequent diagnosis was intracranial hemorrhage (73% bolt vs. 50.4% tunneled group; P < 0.001). Other diagnoses included tumor (4.7% bolt vs. 19.1% tunneled; P < 0.001) and traumatic brain injury (17.5% bolt vs. 17.4% tunneled). In the bolt EVD group 66.4% of EVD tips were optimal, compared with 61.0% in the tunneled group (P= 0.33). Infection was confirmed in 15 (10.0%) bolt EVDs compared with 61 (14.2%) tunneled EVDs (P= 0.2). Each bolt EVD kit costs £260, whereas placing a tunneled one in the theater costs £1316. Bedside bolt EVD placement is safe, accurate, and cost effective in selective patients with hemorrhage-related hydrocephalus.

Endoluminal Shuntscope-Guided Ventricular Catheter Placement: Early Experience.

Background:Placement of ventricular catheter (VC) in an optimal position is the most important factor in determining the outcome of shunt surgery. VC obstruction due to shunt tube placement in brain parenchyma, across the septa, tangled in the choroid plexuses and clogging of VC due to brain matter or other debris are common reasons resulting in shunt complete or partial dysfunction. To resolve these hurdles, many technical advancements have been made including navigation, stereotaxy, sonography, and ventriculoscope-guided VC placement.Objective:To report early experience, technique, and result of placing VC with shuntscope.Methods:We are publishing our experience of shuntscope-guided ventriculoperitoneal shunt in 9 cases done from June 2015 to April 2016. Shuntscope is a 1 mm outer diameter semi-rigid scope from Karl Storz with 10000 pixel of magnification. It has a fiber optic lens system with camera and light source attachment away from the scope to make it light weight and easily maneuverable.Results:In all cases, VC was placed in the ipsilateral frontal horn away from choroid plexuses, septae, or membranes. Septum pellucidum perforation and placement to opposite side of ventricle was identified with shunt scope assistance and corrected.Conclusion:Although our initial results are encouraging, larger case series would be helpful. Complications and cost due to shunt dysfunction can thus be reduced to a great extent with shuntscope.

Factors Predicting Ventriculostomy Revision at a Large Academic Medical Center

Freehand bedside ventriculostomy placement can result in catheter malfunction requiring a revision procedure and cause significant patient morbidity. We performed a single-center retrospective review to assess factors related to this complication. Using an administrative database and chart review, we identified 101 first-time external ventricular drain placements performed at the bedside. We collected data regarding demographics, medical comorbidities, complications, and catheter tip location. We performed univariate and multivariate statistical analyses using MATLAB. We corrected for multiple comparisons using the false discovery rate (FDR) procedure. Multivariate regression analyses revealed that revision procedures were more likely to occur after drain blockage (odds ratio [OR] 17.9) and hemorrhage (OR 10.3, FDR-corrected P values < 0.01, 0.05, respectively). Drain blockage was less frequent after placement in an "optimal location" (ipsilateral ventricle or near foramen of Monroe; OR 0.09, P= 0.009, FDR-corrected P < 0.03) but was more likely to occur after placement in third ventricle (post-hoc P values < 0.015). Primary diagnoses included subarachnoid hemorrhage (n= 30, 29.7%), intraparenchymal hemorrhage with intraventricular extravasation (n= 24, 23.7%), tumor (n= 20, 19.8%), and trauma (n= 17, 16.8%). Most common complications included drain blockage (n= 12, 11.8%) and hemorrhage (n= 8, 7.9%). In total, 16 patients underwent at least 1 revision procedure (15.8%). Bedside external ventricular drain placement is associated with a 15% rate of revision, that typically occurred after drain blockage and postprocedure hemorrhage. Optimal placement within the ipsilateral frontal horn or foramen of Monroe was associated with a reduced rate of drain blockage.

P.126 A nation-wide prospective multi-centre study of external ventricular drainage accuracy, safety, and related complications: Interim analysis

Background: External ventricular drain (EVD) insertion is a common neurosurgical procedure performed in patients with life-threatening conditions, but can be associated with complications. The objectives of this study are to evaluate data on national practice patterns and complications rates in order to optimize clinical care Methods: The Canadian Neurosurgery Research Collaborative conducted a prospective multi-centre registry of patients undergoing EVD insertions at Canadian residency programs Results: In this interim analysis, 4 sites had recruited 46 patients (mean age: 53.9 years, male:female 2:1). Most EVD insertions occurred outside of the operating theatre, using free-hand technique, and performed by junior neurosurgery residents (R1-R3). The catheter tip was in the ipsilateral frontal horn or body of the lateral ventricle in 76% of cases. Suboptimally placed catheters did not have higher rates of short-term occlusion. EVD-related hemorrhage occurred in 6.5% (3/45) with only 1 symptomatic patient. EVD-related infection occurred in 13% (6/46) at a mean of 6 days and was associated with longer duration of CSF drainage (P=0.039; OR: 1.13) Conclusions: Interim results indicate rates of EVD-related complications may be higher than previously thought. This study will continue to recruit patients to confirm these findings and determine specific risk factors associated with them

Flat Panel Detector Computed Tomography−Guided Placement of External Ventricular Drains Using the BrainLAB Headband and Precalibrated Disposable Stylet Instrument: A Cadaveric Feasibility Study

The standard freehand method for the insertion of external ventricular drains (EVDs) is associated with high rates of incorrect placement. Use of neuronavigation has been shown to reduce the rates of inaccurately positioned EVDs. We present a novel neuronavigation-based approach for EVD placement using flat panel detector computed tomography (FDCT) imaging. Four cadaveric heads were used for neuronavigated placement of EVDs using the BrainLAB reference headband in combination with laser surface registration and the precalibrated disposable stylet. In 2 cases, conventional multislice CT imaging was performed to reference neuronavigation. In the other 2 cases, preprocedural imaging was performed with FDCT. After inserting the EVDs, all heads were examined again with the identical imaging method as used before the procedure, followed by evaluation of catheter position. Our data demonstrate that FDCT imaging provides adequate image quality for referencing neuronavigation and performing navigated neurosurgery. All EVDs showed an optimal position in the ipsilateral frontal horn. Use of a BrainLAB reference headband combined with laser surface registration and the precalibrated disposable stylet affords the advantage of not requiring rigid fixation in a clamp. Our presented method is fast, accurate, and easy to use. Furthermore, this study is the first to demonstrate that navigated neurosurgery can be performed on the basis of FDCT imaging.

Image guidance and improved accuracy of external ventricular drain tip position particularly in patients with small ventricles.

External ventricular drain (EVD) insertion is one of the most common emergency neurosurgical procedures. EVDs are traditionally inserted freehand (FH) in an emergency setting, but often result in suboptimal positioning. Image-guided surgery (IGS) is selectively used to assist placement. However, the accuracy and practicality of IGS use is yet to be reported. In this study, the authors set out to assess if IGS is practical and improves the accuracy of EVD placement. Case notes and images obtained in patients who underwent frontal EVD placement were retrospectively reviewed. Ventriculomegaly was determined by the measurement of the Evans index. EVD location was classified as optimal (ipsilateral frontal horn) or suboptimal (any other location). Propensity score matching of the two groups (IGS vs FH) for the Evans index was performed. Data were analyzed for patient age, diagnosis, number of EVDs, and complications. Those without postoperative CT scans were excluded. A total of 607 patients with 760 EVDs placed were identified; 331 met inclusion criteria. Of these, 287 were inserted FH, and 44 were placed with IGS; 60.6% of all unmatched FH EVDs were optimal compared with 75% of the IGS group (p = 0.067). The IGS group had a significantly smaller Evans index (p < 0.0001). Propensity score matching demonstrated improved optimal position in the IGS group when compared with the matched FH group (75% vs 43.2%, OR 4.6 [1.5-14.6]; p = 0.002). Patients with an Evans index of ≥ 0.36 derived less benefit (75% in IGS vs 66% in FH, p = 0.5), and those with an Evans index < 0.36 derived more benefit (75% in IGS vs 53% in FH, p = 0.024). The overall EVD complication rate was 36% in the FH group versus 18% in the IGS group (p = 0.056). Revision rates were higher in the FH group (p = 0.035), and the operative times were similar (p = 0.69). Long intracranial EVD catheters were associated with tip malposition irrespective of the group. Image guidance is practical and improves the accuracy of EVD placement in patients with small ventricles; thus, it should be considered for these patients.

Preliminary Results of Emergency Computed Tomography–Guided Ventricular Drain Placement—Precision for the Most Difficult Cases

External ventricular drainage (EVD) catheter placement is one of the most commonly performed neurosurgical procedures. The study's objective was to compare a computed tomography (CT) bolt scan-guided approach for the placement of EVDs with conventional landmark-based insertion. In this retrospective case-control study, we analyzed patients undergoing bolt-kit EVD catheter placement, either CT-guided or landmark-based, between 2013 and 2016. The CT bolt scan-guided approach was based on a dose-reduced CT scan after bolt fixation with immediate image reconstruction along the axis of the bolt to evaluate the putative insertion axis. If needed, angulation of the bolt was corrected and the procedure repeated before the catheter was inserted. Primary endpoint was the accuracy of insertion. Secondary endpoints were the overall number of attempts, duration of intervention, complication rates, and cumulative radiation dose. In total, 34 patients were included in the final analysis. In the group undergoing CT-guided placement, the average ventricle width was significantly smaller (P=0.04) and average midline shift significantly more pronounced (P= 0.01). CT-guided placement resulted in correct positioning of the catheter in the ipsilateral frontal horn in all 100% of the cases compared with landmark-guided insertion (63%; P= 0.01). Application of the CT-guided approach increased the number of total CT scans (3.6 ± 1.9) and the overall radiation dose (3.34 ± 1.61 mSv) compared with the freehand insertion group (1.84 ± 2.0 mSv and 1.55 ± 1.66 mSv). No differences were found for the other secondary outcome parameters. CT-guided bolt-kit EVD catheter placement is feasible and accurate in the most difficult cases.

Adjustable Ghajar Guide Technique for Accurate Placement of Ventricular Catheters: A Pilot Study.

ObjectiveAn adjustable Ghajar guide is presented to improve the accuracy of the original Ghajar guide technique. The accuracy of the adjustable Ghajar guide technique is also investigated.MethodsThe coronal adjustment angle from the orthogonal catheter trajectory at Kocher’s point is determined based on coronal head images using an electronic picture archiving and communication system. For the adjustable Ghajar guide, a protractor is mounted on a C-shaped basal plate that is placed in contact with the margin of a burrhole, keeping the central 0° line of the protractor orthogonal to the calvarial surface. A catheter guide, which is moved along the protractor and fixed at the pre-determined adjustment angle, is then used to guide the ventricular catheter into the frontal horn adjacent to the foramen of Monro. The adjustable Ghajar guide technique was applied to 20 patients, while a freehand technique based on the surface anatomy of the head was applied to another 47 patients. The accuracy of the ventricular catheter placement was then evaluated using postoperative computed tomography scans.ResultsFor the adjustable Ghajar guide technique (AGT) patients, the bicaudate index ranged from 0.23 to 0.33 (mean±standard deviation [SD]: 0.27±0.03) and the adjustment angle ranged from 0° to 10° (mean±SD: 5.2°±3.2°). All the AGT patients experienced successful cerebrospinal fluid diversion with only one pass of the catheter. Optimal placement of the ventricular catheter in the ipsilateral frontal horn approximating the foramen of Monro (grade 1) was achieved in 19 patients (95.0%), while a suboptimal trajectory into a lateral corner of the frontal horn passing along a lateral wall of the frontal horn (grade 3) occurred in 1 patient (5.0%). Thus, the AGT patients experienced a significantly higher incidence of optimal catheter placement than the freehand catheterized patients (95.0% vs. 68.3%, p=0.024). Moreover, none of the AGT patients experienced any tract hemorrhages along the catheter or procedure-related complications.ConclusionThe proposed adjustable Ghajar guide technique, using angular adjustment in the coronal plane from the orthogonal trajectory at Kocher’s point, facilitates accurate freehand placement of a ventricular catheter for hydrocephalic patients.

Ventriculostomy-associated hemorrhage: a risk assessment by radiographic simulation.

OBJECTIVE Ventriculostomy entry sites are commonly selected by freehand estimation of Kocher's point or approximations from skull landmarks and a trajectory toward the ipsilateral frontal horn of the lateral ventricles. A recognized ventriculostomy complication is intracranial hemorrhage from cortical vessel damage; reported rates range from 1% to 41%. In this report, the authors assess hemorrhagic risk by simulating traditional ventriculostomy trajectories and using CT angiography (CTA) with venography (CTV) data to identify potential complications, specifically from cortical draining veins. METHODS Radiographic analysis was completed on 50 consecutive dynamic CTA/CTV studies obtained at a tertiary-care academic neurosurgery department. Image sections were 0.5 mm thick, and analysis was performed on a venous phase that demonstrated high-quality opacification of the cortical veins and sagittal sinus. Virtual ventriculostomy trajectories were determined for right and left sides using medical diagnostic imaging software. Entry points were measured along the skull surface, 10 cm posteriorly from the nasion, and 3 cm laterally for both left and right sides. Cannulation was simulated perpendicular to the skull surface. Distances between the software-traced cortical vessels and the virtual catheter were measured. To approximate vessel injury by twist drill and ventricular catheter placement, veins within a 3-mm radius were considered a hemorrhage risk. RESULTS In 100 virtual lines through Kocher's point toward the ipsilateral ventricle, 19% were predicted to cause cortical vein injury and suspected hemorrhage (radius ≤ 3 mm). Little difference existed between cerebral hemispheres (right 18%, left 20%). The average (± SD) distance from the trajectory line and a cortical vein was 7.23 ± 4.52 mm. In all 19 images that predicted vessel injury, a site of entry for an avascular zone near Kocher's point could be achieved by moving the trajectory less than 1.0 cm laterally and less than 1.0 cm along the anterior/posterior axis, suggesting that empirical measures are suboptimal, and that patient-specific coordinates based on preprocedural CTA/CVA imaging may optimize ventriculostomy in the future. CONCLUSIONS In this institutional radiographic imaging analysis, traditional methods of ventriculostomy site selection predicted significant rates of cortical vein injury, matching described rates in the literature. CTA/CTV imaging potentiates identification of patient-specific cannulation sites and custom trajectories that avoid cortical vessels, which may lessen the risk of intracranial hemorrhage during ventriculostomy placement. Further development of this software is underway to facilitate stereotactic ventriculostomy and improve outcomes.

Optimizing ventriculoperitoneal shunt placement in the treatment of idiopathic intracranial hypertension: an analysis of neuroendoscopy, frameless stereotaxy, and intraoperative CT.

Cerebrospinal fluid shunting can effectively lower intracranial pressure and improve the symptoms of idiopathic intracranial hypertension (IIH). Placement of ventriculoperitoneal (VP) shunts in this patient population can often be difficult due to the small size of the ventricular system. Intraoperative adjuvant techniques can be used to improve the accuracy and safety of VP shunts for these patients. The purpose of this study was to analyze the efficacy of some of these techniques, including the use of intraoperative CT (iCT) and frameless stereotaxy, in optimizing postoperative ventricular catheter placement. The authors conducted a retrospective review of 49 patients undergoing initial ventriculoperitoneal shunt placement for the treatment of IIH. The use of the NeuroPEN Neuroendoscope, intraoperative neuronavigation, and iCT was examined. To analyze ventricular catheter placement on postoperative CT imaging, the authors developed a new grading system: Grade 1, catheter tip terminates optimally in the ipsilateral frontal horn or third ventricle; Grade 2, catheter tip terminates in the contralateral frontal horn; Grade 3, catheter terminates in a nontarget CSF space; and Grade 4, catheter tip terminates in brain parenchyma. All shunts had spontaneous CSF flow upon completion of the procedure. The average body mass index among all patients was 37.6 ± 10.9 kg/m2. The NeuroPEN Neuroendoscope was used in 44 of 49 patients. Intraoperative CT scans were obtained in 24 patients, and neuronavigation was used in 32 patients. Grade 1 or 2 final postoperative shunt placement was achieved in 90% of patients (44 of 49). In terms of achieving optimal postoperative ventricular catheter placement, the use of iCT was as effective as neuronavigation. Two patients had their ventricular catheter placement modified based on an iCT study. The use of neuronavigation significantly increased time in the operating room (223.4 ± 46.5 vs. 190.8 ± 31.7 minutes, p = 0.01). There were no shunt infections in this study. The use of iCT appears to be equivalent to the use of neuronavigation in optimizing ventricular shunt placement in IIH. Additionally, it may shorten operating room time and limit overall costs.

Case Report: A case report of dry tap during ventriculostomy.

Pneumocephalus following ventriculoperitoneal (VP) shunt insertion is an exceptionally rare occurrence. We report such an event after attempting ventricular puncture (ventriculostomy) for VP shunt insertion and then discuss the management of the same. Dry tap can lead to multiple attempts for ventriculostomy with the associated added risks of complications, as well as complicating the subsequent management. In addition, there is an increased risk of tension pneumocephalus, seizure and shunt failure due to a blockage by air bubbles. Our patient presented with features of raised intracranial pressure two months following craniotomy and evacuation of traumatic subdural hematoma. External ventricular puncture revealed egress of CSF under pressure. Upon attempting VP shunting for post-traumatic hydrocephalus, we experienced dry tap during ventricular puncture that complicated further management. We placed the proximal shunt in the presumed location of the foramen of Monro of ipsilateral frontal horn of lateral ventricle and did not remove the external ventricular drain. Post-operative CT scan revealed pneumoventriculi as the cause for the dry tap during ventricular puncture. Patient was managed with 100% oxygen. He showed gradual improvement and was later discharged. This case shows that variations in the procedure, including head down positioning, adequate cruciate dural incision prior to cortex puncture, and avoiding excessive egress of CSF can help to prevent such complications.

Case Report: A case report of dry tap during ventriculostomy

Pneumocephalus following ventriculoperitoneal (VP) shunt insertion is an exceptionally rare occurrence. We report such an event after attempting ventricular puncture (ventriculostomy) for VP shunt insertion and then discuss the management of the same. Dry tap can lead to multiple attempts for ventriculostomy with the associated added risks of complications, as well as complicating the subsequent management. In addition, there is an increased risk of tension pneumocephalus, seizure and shunt failure due to a blockage by air bubbles. Our patient presented with features of raised intracranial pressure two months following craniotomy and evacuation of traumatic subdural hematoma. External ventricular puncture revealed egress of CSF under pressure. Upon attempting VP shunting for post-traumatic hydrocephalus, we experienced dry tap during ventricular puncture that complicated further management. We placed the proximal shunt in the presumed location of the foramen of Monro of ipsilateral frontal horn of lateral ventricle and did not remove the external ventricular drain. Post-operative CT scan revealed pneumoventriculi as the cause for the dry tap during ventricular puncture. Patient was managed with 100% oxygen. He showed gradual improvement and was later discharged. This case shows that variations in the procedure, including head down positioning, adequate cruciate dural incision prior to cortex puncture, and avoiding excessive egress of CSF can help to prevent such complications.

Guiding protractor for accurate freehand placement of ventricular catheter in ventriculoperitoneal shunting.

While frameless stereotaxis can be used for shunt ventricular catheter placement in patients with smaller ventricles, the ventricular catheter is still commonly placed based on the surface anatomy of the head for patients with larger ventricles. Thus, surgical techniques and guides facilitating accurate and reliable freehand placement of the ventricular catheter still need to be devised. With the patient in a supine position and the axis of their head maintained horizontally, the guiding protractor is placed horizontally in the frontal burrhole at Kocher's point. Using the guiding angle between the head axis and the frontal horn of the lateral ventricle based on coronal head computed tomography (CT) or magnetic resonance (MR) images, the ventricular catheter is then placed in the catheter guide within the guiding protractor. In 20 hydrocephalic patients with a bicaudate index >0.2 or bifrontal distance >25 mm, the ideal guiding angle ranged from 17 to 23° (mean ± standard deviation [SD], 19.6° ± 1.6°). In all these patients, ventricular catheterization was successfully achieved with only one pass of the catheter, and postoperative CT scans showed satisfactory placement of the catheter in the ipsilateral frontal horn of the lateral ventricles. The proposed surgical technique using a guiding protractor facilitates accurate freehand placement of a ventricular catheter for patients with a bicaudate index >0.2 or bifrontal distance >25 mm.