Ultrasound-Guided Insertion of the Ventricular Catheter in Ventriculoperitoneal Shunt Surgery: Evaluation of Accuracy and Feasibility in a Prospective Cohort

ShuntScope-Guided Versus Free-Hand Technique for Ventricular Catheter Placement: A Retrospective Comparative Study of Intraventricular Catheter Tip Position and Complication Rate

BACKGROUND

 The position of the ventricular catheter (VC) is essential for a proper function of cerebrospinal fluid diversion system. A ShuntScope-guided (SG) method might be helpful in reducing complications. The purpose of this study is to compare the accuracy of catheter placement and the complication and revision rates between SG and free-hand (FH) techniques.

METHODS

 This is a retrospective study based on a prospectively acquired database of patients who underwent VC placement between September 2018 and July 2021. Accuracy of catheter placement was graded on postoperative imaging using the 3-point Hayhurst grading system. Complication and revision rates were documented and compared between both groups with an average follow-up period of 20.84 months.

RESULTS

 Fifty-seven patients were included. The SG technique was used in 29 patients (mean age was 6.3 years, 1.4-27.7 years, 48.1% females), and the FH technique was used in 28 patients (mean age was 26.7 years, 0.83-79.5 years, 67.9% female). The success rate for the optimal placement of the VC with grade I on the Hayhurst scale was significantly higher in the SG group (93.1%) than in the FH group (60.7%), p = 0.012. The revision rate was higher in the FH group with 35.7% versus 20.7% in the SG group, p = 0.211.

CONCLUSION

 VC placement using the SG technique is a safe and effective procedure, which enabled a significantly higher success rate and lower revision and complication rate. Accordingly, we recommend using the SG technique especially in patients with difficult anatomy.

Intraoperative ultrasound-guided ventricular cannulation in patients with normal-sized ventricles

INTRODUCTION

Many pathologies require normal-sized ventricle cannulation, which may be technically challenging even with neuronavigation guidance. This study presents a series of ventricular cannulation of normal-sized ventricles using intraoperative ultrasound (iUS) guidance and the outcomes of patients treated by this technique, for the first time.

METHODS

The study included patients who underwent ultrasound-guided ventricular cannulation of normal-sized ventricles (either ventriculoperitoneal (VP) shunting or Ommaya reservoir) between January 2020 and June 2022. All patients underwent iUS-guided ventricular cannulation from the right Kocher's point. The inclusion criteria for normal-sized ventricles were as follows: (1) Evans index <30%, and (2) widest third ventricle diameter <6mm. Medical records and pre-, intra- and post-operative imaging were retrospectively analyzed.

RESULTS

Nine of the 18 included patients underwent VP shunt placement; 6 had idiopathic intracranial hypertension (IIH), 2 had resistant cerebrospinal fluid fistula following posterior fossa surgery, and 1 had iatrogenic intracranial pressure elevation following foramen magnum decompression. Nine patients underwent Ommaya reservoir implantation, 6 of whom had breast carcinoma and leptomeningeal metastases and 3 hematologic disease and leptomeningeal infiltration. All catheter tip positions were achieved in a single attempt, and none were placed suboptimally. Mean follow-up was 10 months. One IIH patient (5.5%) had early shunt infection which necessitated shunt removal.

CONCLUSION

iUS is a simple and safe method for accurate cannulation of normal-sized ventricles. It provides an effective real-time guidance option for challenging punctures.

Improved Accuracy and Lowered Learning Curve of Ventricular Targeting Using Augmented Reality-Phantom and Cadaveric Model Testing

BACKGROUND

Augmented reality (AR) has demonstrated significant potential in neurosurgical cranial, spine, and teaching applications. External ventricular drain (EVD) placement remains a common procedure, but with error rates in targeting between 10% and 40%.

OBJECTIVE

To evaluate Novarad VisAR guidance system for the placement of EVDs in phantom and cadaveric models.

METHODS

Two synthetic ventricular phantom models and a third cadaver model underwent computerized tomography imaging and registration with the VisAR system (Novarad). Root mean square (RMS), angular error (γ), and Euclidian distance were measured by multiple methods for various standard EVD placements.

RESULTS

Computerized tomography measurements on a phantom model (0.5-mm targets showed a mean Euclidean distance error of 1.20 ± 0.98 mm and γ of 1.25° ± 1.02°. Eight participants placed EVDs in lateral and occipital burr holes using VisAR in a second phantom anatomic ventricular model (mean RMS: 3.9 ± 1.8 mm, γ: 3.95° ± 1.78°). There were no statistically significant differences in accuracy for postgraduate year level, prior AR experience, prior EVD experience, or experience with video games ( P > .05). In comparing EVDs placed with anatomic landmarks vs VisAR navigation in a cadaver, VisAR demonstrated significantly better RMS and γ, 7.47 ± 0.94 mm and 7.12° ± 0.97°, respectively ( P ≤ .05).

CONCLUSION

The novel VisAR AR system resulted in accurate placement of EVDs with a rapid learning curve, which may improve clinical treatment and patient safety. Future applications of VisAR can be expanded to other cranial procedures.

Distal shunt placement in pediatric ventriculoperitoneal shunt surgery: an international survey of practice

OBJECTIVE

Ventriculoperitoneal shunt (VPS) surgery is a common treatment for hydrocephalus in children and adults, making it one of the most common procedures in neurosurgery. Children being treated with a VPS often require several revisions during their lifetime with a lifetime revision rate of up to 80%. Several different techniques exist for inserting the distal catheter, while mini-laparotomy, trocar, or laparoscopy is traditionally used. As opposed to adults, only few studies exist, comparing the outcome of the different distal catheter placement techniques in children. This international survey aims to investigate the current daily practice concerning distal shunt placement techniques in children.

MATERIAL AND METHODS

An online questionnaire investigating the different techniques used to place the distal catheter in pediatric VPS surgery was distributed internationally. All results were analyzed using descriptive and comparative statistics.

RESULTS

A total of 139 responses were obtained. Mini-laparotomy was reported to be the most frequently used technique (n = 104, 74.8%) for distal shunt placement in children, while laparoscopic or trocar-assisted placements were only used by 3.6% (n = 5) and 21.6% (n = 30) of all respondents, respectively. Over half (n = 75, 54.0%) of all respondents do not believe that laparoscopic placement improves the outcome.

CONCLUSION

This international survey shows that mini-laparotomy is the most frequently used technique for distal VPS placement in children all over the world. Further randomized trials are needed to elucidate this matter.

The Birmingham Standardized Idiopathic Intracranial Hypertension Shunt Protocol: Technical Note

BACKGROUND

Insertion of cerebrospinal fluid (CSF) shunts in patients with idiopathic intracranial hypertension (IIH) is challenging mainly due to the small ventricles and phenotypical body habitus. In this report the authors present their surgical protocol for insertion of a ventriculoperitoneal shunt (VPS) in patients with IIH and the associated revision rates.

METHODS

The protocol comprises the following: shunt surgery by neurosurgeons with expertise in CSF disorders; a frontal VPS usually right sided but left sided if the left ventricle is bigger; use of the proGAV 2.0 valve with gravitational unit, set at 10 and the M.scio telemetric sensor; cannulation of the ventricle with StealthStation EM navigation system; and laparoscopic insertion of the peritoneal catheter. The authors describe the protocol and rationale and evidence behind each component and present the results of a prospective analysis on revision rates.

RESULTS

The protocol has been implemented since 1 July, 2019, and by 28 February, 2022, sixty-two patients with IIH had undergone primary VPS insertion. The 30-day revision rate was 6.5%, and overall 11.3% of patients underwent revision during the study period, which compares favorably with the literature. The etiology for early failures was related to the surgical technique.

CONCLUSIONS

The components of the Birmingham standardized IIH shunt protocol are evidence based and address the technical challenges of CSF diversion in patients with IIH. This protocol is associated with a low revision rate, and the authors recommend standardization for CSF shunting in IIH.

Image-Guided versus Freehand Ventricular Drain Insertion: Systematic Review and Meta-analysis

BACKGROUND

Ventricular drain insertion is a common neurosurgical procedure, typically performed using freehand approach. Use of image-guidance during drain insertion could improve the accuracy and reduce the incidence of drain failure. This review aim to assess the impact of image-guidance on drain placement accuracy, failure rate, and number of ventricular cannulation attempts.

METHODS

MEDLINE, EMBASE and Cochrane Library databases were searched from inception to February 2021 for studies comparing image-guided versus freehand ventricular drain insertion. Two reviewers independently screened studies for eligibility, extracted data, and assessed risk of bias and quality of evidence. Pooled data were reported using random effects model. ROBINS-I tool was used to assess risk of bias and GRADE approach was used to assess quality of evidence.

RESULTS

Of 1102 studies retrieved, 17 were included with a total of 3404 patients. . All included studies were of non-randomized design. Pooled data on drain accuracy and drain failure rates showed favourable effect of image-guidance with risk ratio of 1.31 (95% CI of 1.13 - 1.51, low quality evidence) and 0.63 (95% CI 0.48 - 0.83, moderate quality evidence), respectively. Pooled data were equivocal for number of attempts with mean difference score of -0.11 times (95% CI -0.31 - 0.09, very low-quality evidence). Heterogeneity was substantial for drain accuracy and failure rate outcomes.

CONCLUSIONS

In patients undergoing ventricular drain insertion, the use of image-guidance may enhance drain accuracy and reduce drain failure rate. The use of image-guidance probably does not decrease number of drain insertion attempts.

Versatile Use of Intraoperative Ultrasound Guidance for Brain Puncture

BACKGROUND

Intraoperative ultrasound (iUS) is an effective guidance and imaging system commonly used in neuro-oncological surgery. Despite the versatility of iUS, its utility for single burr hole puncture guidance remains fairly underappreciated.

OBJECTIVE

To highlight the simplicity, versatility, and effectiveness of iUS guidance in brain puncture by presenting the current case series and technical note collection.

METHODS

We present 4 novel uses of iUS guidance for single burr hole brain puncture: cannulation of normal-sized ventricles, endoscopic third ventriculostomy (ETV) guidance, evacuation of interhemispheric empyema, and stereotactic biopsy assistance.

RESULTS

All techniques were performed successfully in a total of 16 patients. Normal-sized ventricles were cannulated in 7 patients, among whom 5 underwent Ommaya reservoir placement and 2 underwent ventriculoperitoneal shunt placement for idiopathic intracranial hypertension. No more than 1 attempt was needed for cannulation. All ventricular tip positions were optimal as shown by postoperative imaging. iUS guidance was used in 5 ETV procedures. The working cannula was successfully introduced to the lateral ventricle, providing the optimal trajectory to the third ventricular floor in these cases. Interhemispheric subdural empyema was aspirated with iUS guidance in 1 patient. Volume reduction was clearly visible, allowing near-total evacuation of the empyema. iUS guidance was used for assistive purposes during stereotactic biopsy in 3 patients. No major perioperative complications were observed throughout this series.

CONCLUSION

iUS is an effective and versatile guidance system that allows for real-time imaging and can be easily and safely employed for various brain puncture procedures.

Intraoperative ultrasound-guided compared to stereotactic navigated ventriculoperitoneal shunt placement: study protocol for a randomised controlled study

BACKGROUND

Ventriculoperitoneal shunt (VPS) placement is one of the most frequent neurosurgical procedures and the operation is performed in a highly standardised manner under maintenance of highest infection precautions. Short operation times are important since longer duration of surgery can increase the risk for VPS complications, especially infections. The position of the proximal ventricular catheter influences shunt functioning and survival. With freehand placement, rates of malpositioned VPS are still high. Several navigation techniques for improvement of shunt placement have been developed. Studies comparing these techniques are sparse. The aim of this study is to prospectively compare ultrasound (US) guided to stereotactic navigated shunt placement using optical tracking with the focus on operation time and efficiency.

METHODS

In this prospective randomised, single-centre, partially-blinded study, we will include all patients undergoing VPS placement in our clinic. The patients will be randomised into two groups, one group undergoing US-guided (US-G) and the other group stereotactic navigated VPS placement using optical tracking. The primary outcome will be the surgical intervention time. This time span consists of the surgical preparation time together with the operation time and is given in minutes. Secondary outcomes will be accuracy of catheter positioning, VPS dysfunction and need for revision surgery, total operation and anaesthesia times, and amount of intraoperative ventricular puncture attempts as well as complications, any morbidity and mortality.

DISCUSSION

To date, there is no prospective data available comparing these two navigation techniques. A randomised controlled study is urgently needed in order to provide class I evidence for the best possible surgical technique of this frequent surgery.

TRIAL REGISTRATION

Business Administration System for Ethical Committees (BASEC) 2019-02157, registered on 21 November 2019, https://www.kofam.ch/de/studienportal/suche/88135/studie/49552 ; clinicalTrials.gov: NCT04450797 , registered on 30 June 2020.