Freehand External Ventricular Drain Research Articles

Freehand frontal external ventricular drain (EVD) placement: Accuracy and complications

Ventriculostomy placement is a life-saving procedure. Our aim was to determine the predictors of inaccurate placement, our infection and hemorrhage rate. This was a retrospective study of EVD placements between January - November 2019. Data related to hemorrhage, infection and catheter misplacement were collected. Univariate and multivariate analyses of predictors of suboptimal catheter placement were performed. 131 consecutive patients underwent freehand EVD placement. The indications were subarachnoid hemorrhage in 36 (27.5%) patients, hemorrhagic stroke in 36 (27.5%), and trauma in 32 (24.4%) patients. Nine patients (6.8%) had culture-proven CSF bacterial infection. Sixteen (12.2%) patients developed small tract hemorrhage, while 8 (6.1%) patients developed large intraparenchymal hemorrhage. There was no correlation between tract hemorrhage or large hemorrhage with the use of antiplatelet or anticoagulation medicines on presentation, diagnosis or Kakarla grade. Trauma diagnosis (odds ratio 2.59, p-value 0.05), left side of EVD placement (odds ratio 2.84, p-value 0.03), increasing midline shift (odds ratio 1.09, p-value 0.03), and lower bicaudate index (odds ratio 0.56, p-value 0.02) were all predictors of Kakarla grade 3 suboptimal placement. When Kakarla grade 2 and 3 were combined, similar results were obtained except that midline shift was no longer statistically significant. The multivariable regression model predicting Kakarla 3 suboptimal placement revealed that low bicaudate index and left sided EVD were predictors of misplaced EVD.

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.

Is Image Guidance Essential for External Ventricular Drain Insertion?

This study aimed to compare the external ventricular drain (EVD) placement accuracy and complication rates, between neuronavigation-guided, ultrasound-guided, and freehand techniques in our single-center cohort, and through an additional meta-analysis of the currently available literature. A retrospective review of patients who underwent EVD insertion from January 2016 to April 2019 was conducted. Information regarding demographics, indication, Evans index, use of image guidance, accuracy of catheter tip placement, and procedural complications was extracted from electronic records and imaging systems. The accuracy of the EVD tip placement was classified according to the Kakarla grading system into optimal, or suboptimal based on its proximity to the Foramen of Monro and involvement of noneloquent/eloquent structures. In total, 294 patients (median age of 54 years) underwent EVD insertion during the study period. A total of 183 catheters were placed freehand, 66 neuronavigation-guided, and 45 ultrasound-guided; the mean Evans ratios were 0.33, 0.29, and 0.31, respectively. Whilst there was a tendency for lower rates of suboptimal placement were guidance was used, with rates of 10.6% and 15.6% for neuronavigation- and ultrasound-guidance, respectively, compared to 20.8% in freehand placement, this did not reach statistical significance (P = 0.168). However, pooling this data with two additional studies on meta-analysis found a significant reduction in the risk of suboptimal placement for image-guided vs. freehand EVDs (odds ratio: 0.50, 95% CI: 0.32-0.77, P = 0.002). Surgeon seniority and other procedure-related factors had no significant impact on EVD placement accuracy or complications. Our results, pooled with those of previous studies, suggest image-guided EVD placement significantly reduced the rate of suboptimally placed EVDs. We conclude in appropriately selected cases that image-guided EVD insertions may improve accuracy of catheter placements and reduce associated complications of the procedure.

Freehand external ventricular drain insertion - is there a learning curve?

Background: Accuracy of freehand insertion of external ventricular drains (EVDs) is influenced by many factors including etiology and presence of midline shift. We sought to assess if junior neurosurgical trainees’ performance in accurately inserting EVDs improves with experience, using a radiological grading system.Methods: EVD insertion procedures from the first 3 years of training were identified from the operative logbooks of three trainees. Postoperative CT head scans were graded for accuracy of placement and intraventricular catheter length.Results: 40 frontal EVDs performed primarily by the trainees were identified, after 34 assists, revision surgeries, parietal, or occipital insertions were excluded from the study. The mean number (±1 SD) of procedures was 7.7 ± 4.5 at ST3, 4.7 ± 2.5 at ST2, and 1 ± 1 at ST1. About 80% of EVDs were optimally inserted. There was no statistically significant difference in placement accuracy between the three training grades (P = 0.669), nor any difference in intraventricular catheter length (P = 0.697). There were no statistically significant differences between surgeons’ accuracy at each grade.Conclusion: We report good accuracy of EVDs tip position inserted by junior neurosurgery trainees. Trainees perform more procedures independently as they progress in their career. Further studies including senior years of training performance, other procedure factors and outcome should be considered.

Determinants of accuracy of freehand external ventricular drain placement by neurosurgical trainees.

The external ventricular drain (EVD) placement is one of the most common neurosurgical procedures. This operation is performed by freehand technique in the majority of cases; therefore, the operator's experience plays an important role in success and possible morbidity of this procedure. To evaluate the accuracy and safety of EVD placement by junior neurosurgery residents and factors predicting accuracy of EVD placement. This is a prospective cohort study conducted at our academic medical center, between September 2017 and August 2018. All patients 18years or older who required EVD placement were included. The accuracy and complications of EVD placement were assessed in the first and second year resident cohorts as well as by their level of experience, using descriptive statistics. Univariate and multivariate models were used to assess predictive factors for optimal EVD. A total of 100 EVDs were placed in 100 patients during the study period. According to Kakarla classification, the catheter was optimally placed in 80% of cases. The first year residents had a significantly higher rate of suboptimal burr hole placement compared to the second year residents (66.7% versus 27.1%, p = 0.004). The trainees with less than 10 EVD placement experience also had a significantly higher rate of suboptimal burr hole placement (55.2% vs. 23.9%, p = 0.003), significantly longer duration of operation (43.1min ± 14.9SD vs 34.2min ± 9.6 p = 0.005), and significantly lower rate of optimal EVD location (85.9% versus 65.5%, p = 0.023). Optimal location of the burr hole was the only significant predictor of optimal EVD placement in multivariate analysis (OR 11.9, 95% CI 3.2-44.6, p < 0.001). Neurosurgery residents experience and optimal burr hole placement are the main predicators of accurate EVD placement.

A virtual reality-based data analysis for optimizing freehand external ventricular drain insertion.

This work exploits virtual reality technique to analyse and optimize the preoperative planning of freehand external ventricular drain (EVD) insertion. Based on the three-dimensional (3D) virtual brain models, neurosurgeons can directly observe the anatomical landmarks and complete the simulated EVD insertion. Simulation data is used to optimize preoperative planning parameters to ensure the surgical performance. We used the computed tomography (CT) scans to construct the 3D virtual brain models. A group of EVD insertions were simulated by inserting virtual catheters at different entry points. The key parameters including the location of entry point, the catheter orientation, the catheter tip position on lateral ventricles, and the insertion depth were recorded. A data analysis method was then applied to optimize these parameters, resulting in the optimal parameters for the EVD insertion. When the lateral distance of entry point ranged from 2.5 to 3cm, the success rate of 204 cases was 97.79%, which was higher than that of the classic method (59.52%). The optimal insertion angle towards the sagittal plane ranged from 10.46° to 12.73°. To prevent penetrating the lateral ventricles, the insertion depth was optimized to be 3.28 to 4.58cm. The proposed data analysis method is helpful to optimize the key parameters of the preoperative planning, and provides useful references for neurosurgeons to perform the freehand EVD insertion. The EVD insertion experiments on 3D printing model had a success rate of 93.75%, which verified the effectiveness of the data analysis.

Accuracy of freehand external ventricular drain placement in patients after a large decompressive hemicraniectomy

Our study aim is to evaluate the accuracy of freehand external ventricular drain (EVD) placement, without the use of adjuncts to placement, immediately following a large decompressive hemicraniectomy (DC). We performed a retrospective cohort analysis comparing patients who underwent freehand EVD placement immediately after a DC, to those who underwent freehand EVD placement without DC. Computed tomography (CT) studies were used to assess accuracy based on catheter tip location. Intracranial catheter length, pre- and post-operative Evan’s Index, and midline shift pre- and post-operatively were analysed as separate variables in each group. A previously described grading system was used to assess the accuracy of free hand EVD placement. There were a total 110 patients overall; DC group, n = 50; non-DC group, n = 60. There was a significant reduction from pre-operative midline shift to post-operative midline shift in the DC group (9.13 vs 6.02 mm; p = 0.0064). There was no significant difference in accuracy between the two groups (p = 0.8917), and similar rates of Grade 1 – i.e. optimal – catheter tip location (DC = 78% vs non-DC = 81%) were found. All analysed variables comparing both Grade 1 subgroups (pre- and postoperative Evan’s Index, and midline shift) showed significant differences between them. Mean catheter length in Grade 1 EVD placement showed a statistically significant difference between the DC and non-DC groups (63.78 vs 59.96 mm, respectively; p = 0.009). An EVD, after DC for traumatic and non-traumatic intracranial pathologies, can be accurately placed by freehand.

Freehand Insertion of External Ventricular Drainage Catheter: Evaluation of Accuracy in a Single Center.

Introduction:External ventricular drain (EVD) placement is the gold standard for managing acute hydrocephalus. Freehand EVD, using surface anatomical landmarks, is performed for ventricular cannulation due to its simplicity and efficiency. This study evaluates accuracy and reason(s) for misplacements as few studies have analyzed the accuracy of freehand EVD insertion.Patients and Methods:Preoperative and postoperative computed tomography scans of patients who underwent EVD insertion in 2014 were retrospectively reviewed. Diagnosis, Evans ratio, midline shift, position of burr hole, length of the catheter, and procedural complications were tabulated. The procedures were classified as satisfactory (catheter tip in the frontal horn ipsilateral lateral ventricle) and unsatisfactory. Unsatisfactory cases were further analyzed in relation to position of burr hole from midline and length of the catheter.Results:Seventy-seven EVD placements in seventy patients were evaluated. The mean age of the patients was 57.5 years. About 83.1% were satisfactory placements and 11.7% were unsatisfactory in the contralateral ventricle, corpus callosum, and interhemispheric fissure. Nearly 5.2% were in extraventricular locations. Almost 2.6% EVD placements were complicated by hemorrhage and 1 catheter was reinserted. Suboptimal placements were significantly associated with longer intracranial catheter length. The mean length was 66.54 ± 10.1 mm in unsatisfactory placements compared to 58.32 ± 4.85 mm in satisfactory placements. Between the two groups, no significant difference was observed in Evans ratio, midline shift, surgeon's experience, distance of burr hole from midline, and coronal suture.Conclusion:Freehand EVD insertion is safe and accurate. In small number of cases, unsatisfactory placement is related to longer catheter length.

A wearable mixed-reality holographic computer for guiding external ventricular drain insertion at the bedside.

The goal of this study was to explore the feasibility and accuracy of using a wearable mixed-reality holographic computer to guide external ventricular drain (EVD) insertion and thus improve on the accuracy of the classic freehand insertion method for EVD insertion. The authors also sought to provide a clinically applicable workflow demonstration. Pre- and postoperative CT scanning were performed routinely by the authors for every patient who needed EVD insertion. Hologram-guided EVD placement was prospectively applied in 15 patients between August and November 2017. During surgical planning, model reconstruction and trajectory calculation for each patient were completed using preoperative CT. By wearing a Microsoft HoloLens, the neurosurgeon was able to visualize the preoperative CT-generated holograms of the surgical plan and perform EVD placement by keeping the catheter aligned with the holographic trajectory. Fifteen patients who had undergone classic freehand EVD insertion were retrospectively included as controls. The feasibility and accuracy of the hologram-guided technique were evaluated by comparing the time required, number of passes, and target deviation for hologram-guided EVD placement with those for classic freehand EVD insertion. Surgical planning and hologram visualization were performed in all 15 cases in which EVD insertion involved holographic guidance. No adverse events related to the hologram-guided procedures were observed. The mean ± SD additional time before the surgical part of the procedure began was 40.20 ± 10.74 minutes. The average number of passes was 1.07 ± 0.258 in the holographic guidance group, compared with 2.33 ± 0.98 in the control group (p < 0.01). The mean target deviation was 4.34 ± 1.63 mm in the holographic guidance group and 11.26 ± 4.83 mm in the control group (p < 0.01). This study demonstrates the use of a head-mounted mixed-reality holographic computer to successfully perform hologram-assisted bedside EVD insertion. A full set of clinically applicable workflow images is presented to show how medical imaging data can be used by the neurosurgeon to visualize patient-specific holograms that can intuitively guide hands-on operation. The authors also provide preliminary confirmation of the feasibility and accuracy of this hologram-guided EVD insertion technique.

Accuracy and Complications of Free-Hand External Ventricular Drain Placement: Preliminary Results of a Prospective Observational Study

Accuracy and Complications of Free-Hand External Ventricular Drain Placement: Preliminary Results of a Prospective Observational Study