Comparing ventriculoatrial and ventriculopleural shunts in pediatric hydrocephalus: a Hydrocephalus Clinical Research Network study.

OBJECTIVE: When the peritoneal cavity cannot serve as the distal shunt terminus, nonperitoneal shunts, typically terminating in the atrium or pleural space, are used. The comparative effectiveness of these two terminus options has not been evaluated. The authors directly compared shunt survival and complication rates for ventriculoatrial (VA) and ventriculopleural (VPl) shunts in a pediatric cohort. METHODS: The Hydrocephalus Clinical Research Network Core Data Project was used to identify children ≤ 18 years of age who underwent either VA or VPl shunt insertion. The primary outcome was time to shunt failure. Secondary outcomes included distal site complications and frequency of shunt failure at 6, 12, and 24 months. RESULTS: The search criteria yielded 416 children from 14 centers with either a VA (n = 318) or VPl (n = 98) shunt, including those converted from ventriculoperitoneal shunts. Children with VA shunts had a lower median age at insertion (6.1 years vs 12.4 years, p < 0.001). Among those children with VA shunts, a hydrocephalus etiology of intraventricular hemorrhage (IVH) secondary to prematurity comprised a higher proportion (47.0% vs 31.2%) and myelomeningocele comprised a lower proportion (17.8% vs 27.3%) (p = 0.024) compared with those with VPl shunts. At 24 months, there was a higher cumulative number of revisions for VA shunts (48.6% vs 38.9%, p = 0.038). When stratified by patient age at shunt insertion, VA shunts in children < 6 years had the lowest shunt survival rate (p < 0.001, log-rank test). After controlling for age and etiology, multivariable analysis did not find that shunt type (VA vs VPl) was predictive of time to shunt failure. No differences were found in the cumulative frequency of complications (VA 6.0% vs VPl 9.2%, p = 0.257), but there was a higher rate of pneumothorax in the VPl cohort (3.1% vs 0%, p = 0.013). CONCLUSIONS: Shunt survival was similar between VA and VPl shunts, although VA shunts are used more often, particularly in younger patients. Children < 6 years with VA shunts appeared to have the shortest shunt survival, which may be a result of the VA group having more cases of IVH secondary to prematurity; however, when age and etiology were included in a multivariable model, shunt location (atrium vs pleural space) was not associated with time to failure. The baseline differences between children treated with a VA versus a VPl shunt likely explain current practice patterns.

The association of COVID-19 with increased pediatric ventriculoatrial shunt failures: a national retrospective cohort.

OBJECTIVE: During the COVID-19 pandemic, the authors' institution managed ventriculoatrial (VA) shunt complications in 2 teenage patients in close proximity to a symptomatic COVID-19 infection. Systemic thrombotic events are an established complication of COVID-19 infection due to a hypercoagulable state. Thrombotic complications, particularly elevated central venous pressure, can cause VA shunt failure. The true effect of COVID-19 on patients with intravascular devices is currently unknown. In this study, the authors aimed to determine if there was an association between COVID-19 infection and VA shunt failure. METHODS: TriNetX, an aggregated electronic health record platform, was used to analyze data of more than 13 million US pediatric patients. Two matched cohorts of patients < 18 years of age with a VA shunt were defined. Group 1 (n = 311) had a positive laboratory test for COVID-19 from March 1, 2020, to March 31, 2022. Group 2 (n = 311), a control group, had any medical appointment from March 1, 2020, to March 31, 2022, and never had a positive laboratory test for COVID-19. The authors analyzed outcomes 1 year after testing positive for COVID-19 in group 1, and after the medical appointment in group 2. Outcomes included shunt complications, shunt revisions or replacements, and thromboembolic complications. To protect patient privacy, individual results of fewer than 10 patients are not specified in TriNetX. RESULTS: Group 1 had a greater odds of mechanical shunt complication than group 2 (20% vs 4%, OR 5.71, 95% CI 3.07-10.62). Group 1 had a greater odds of shunt reoperation than group 2 (11% vs < 3%, OR > 3.7, 95% CI 1.72-7.62). There were 1-10 patients in group 1 (≤ 3% of group 1) who experienced a thromboembolism due to the shunt, compared with no patients in group 2 who had a thromboembolism due to the shunt. CONCLUSIONS: This analysis demonstrates an association of shunt complications, reoperations, and thromboembolic events in patients with VA shunts following COVID-19 infection.

Lumbar Lordosis is a Risk Factor for Lumbar Catheter Fracture of Lumboperitoneal Shunt.

OBJECTIVE: This study aimed to investigate the causes of lumboperitoneal (LP) shunt failure and determine risk factors for lumbar catheter fracture. METHODS: We retrospectively investigated 149 patients who underwent LP shunting in our hospital between January 2012 and March 2023. Shunt reconstruction occurred in 22 patients (14.8%). Among these, cause of failure was lumbar catheter fracture in 5 (22.7%). Patient backgrounds, cause of LP shunt failure, surgical technique factors, and anatomical characteristics were extracted for comparative analysis and risk factors of lumbar catheter fracture were analyzed. RESULTS: Compared with the no reoperation group (n = 127), patients in the lumbar catheter fracture tended to be younger (63 ± 20 vs. 72 ± 11 years) and favorable neurologic status (modified Rankin scale score ≤2) after initial LP shunt; however, the differences were not significant. Lumbar lordosis was significantly higher in the lumbar catheter fracture group (52.7°± 14.8° vs. 37.1°± 12.3°; P = 0.0067). CONCLUSIONS: Excessive lumbar lordosis is a risk factor for lumbar catheter fracture in patients undergoing LP shunting. Younger age and higher level of postoperative activities of daily living might also be associated with lumbar catheter fracture.

Development of an in vitro ventricular shunt material testing model and utility of PEG as antifouling coating.

OBJECTIVE: CSF shunts, most commonly the ventriculoperitoneal shunt, remain a first and last line of management for children and adults with hydrocephalus. However, the failure rates of these shunts are extremely high, leaving many patients with the need for revision surgical procedures. The objective of this study was to develop a model to assess the efficacy of a nonfouling ventricular catheter. A second objective was to test polyethylene glycol (PEG) as an antifouling coating. METHODS: Microglial cells were grown on medical-grade catheter silicone with biofouling simulated by collagen incubation over a range of concentrations from 31 to 103 µg/ml and durations from 2 to 18 hours. After ideal fouling conditions were identified, catheter silicone was then coated with PEG as an antifouling surface, and cell growth on this surface was compared to that on uncoated standard catheter silicone. RESULTS: Collagen biofouling increased cell growth on silicone surfaces with an ideal concentration of 69 µg/ml and incubation of 6 hours. PEG coating of silicone catheter material yielded 70-fold lower cell growth (p < 0.0001), whereas collagen-fouled PEG-coated silicone yielded 157-fold lower cell growth (p < 0.0001). CONCLUSIONS: Catheter coating significantly reduced cell growth, particularly in the setting of biofouling. The application of antifouling surfaces to ventricular shunts shows considerable promise for improving efficacy.

Pediatric shunt failure: finding predictability in the sea of uncertainty.

OBJECTIVE: Shunt malfunction is a complication that can have devastating implications. In this study, the authors aimed to evaluate the rate of shunt revision in a single institution over 5 years and to determine the factors associated with shunt revision in the pediatric population. METHODS: This retrospective report assimilated data from all patients ≤ 18 years old who underwent shunt surgery between January 2015 and April 2021 at the authors' institute with a minimum of 3 months of follow-up. Patient data regarding demographic characteristics, indications, clinical status, point of entry, operative and CSF findings, revision interval, and cause of failure were collected. RESULTS: Between January 2015 and April 2021, 1112 pediatric patients underwent initial shunt surgery at the authors' institute, among whom 934 patients met the inclusion criteria. Ninety-five patients underwent revision (shunt revision rate 10.2%). The cohort comprised 562 male and 368 female patients (no sex was recorded in 4 cases), with infratentorial tumors (37.8%) being the most common indication for the shunt. Multivariate analyses revealed that younger patient age, right-sided shunt, single surgeon, and shunt placement done in the evening and night were significantly associated with shunt failure. Among all the factors analyzed, female sex had the greatest risk of early shunt failure (OR 2.90 [95% CI 1.09-8.16], p = 0.037). The presence of prior external ventricular drainage was associated with an increased risk of multiple revisions (OR 6.67 [95% CI 1.60-32.52], p = 0.012). The most common cause of failure was obstruction, usually at the cranial end. The most common cause of distal failure was malposition of the abdominal end. CONCLUSIONS: This study identifies various factors associated with shunt failure. Various goal-directed strategies toward modifiable risk factors can significantly improve shunt survival.

Implantable Intracranial Pressure Sensor with Continuous Bluetooth Transmission via Mobile Application.

Hydrocephalus is a clinical disorder caused by excessive cerebrospinal fluid (CSF) buildup in the ventricles of the brain, often requiring permanent CSF diversion via an implanted shunt system. Such shunts are prone to failure over time; an ambulatory intracranial pressure (ICP) monitoring device may assist in the detection of shunt failure without an invasive diagnostic workup. Additionally, high resolution, noninvasive intracranial pressure monitoring will help in the study of diseases such as normal pressure hydrocephalus (NPH) and idiopathic intracranial hypertension (IIH). We propose an implantable, continuous, rechargeable ICP monitoring device that communicates via Bluetooth with mobile applications. The design requirements were met at the lower ICP ranges; the obtained error fell within the idealized ±2 mmHg margin when obtaining pressure values at or below 20 mmHg. The error was slightly above the specified range at higher ICPs (±10% from 20-100 mmHg). The system successfully simulates occlusions and disconnections of the proximal and distal catheters, valve failure, and simulation of A and B ICP waves. The mobile application accurately detects the ICP fluctuations that occur in these physiologic states. The presented macro-scale prototype is an ex-vivo model of an implantable, rechargeable ICP monitoring system that has the potential to measure clinically relevant ICPs and wirelessly provide accessible and continuous data to aid in the workup of shunt failure.

Cerebrospinal fluid shunt malfunctions: A reflective review.

PURPOSE: Pediatric hydrocephalus is a common and challenging condition. To date, the ventriculoperitoneal shunt (VPS) is still the main lifesaving treatment option. Nonetheless, it remains imperfect and is associated with multiple short- and long-term complications. This paper is a reflective review of the current state of the VPS, our knowledge gaps, and the future state of shunts in neurosurgical practice. METHODS AND RESULTS: The authors' reflections are based on a review of shunts and shunt-related literature. CONCLUSION: Overall, there is still an urgent need for the neurosurgical community to actively improve current strategies for shunt failures and shunt-related morbidity. The authors emphasize the role of collaborative efforts amongst like-minded clinicians to establish pragmatic approaches to avoid shunt complications.

Exploration of clinical predictors of the degree of ventricular catheter obstruction: a multicenter retrospective study.

OBJECTIVE: The aim of this study was to explore how clinical factors, including the number of lifetime revision surgeries and the duration of implantation, affect the degree of obstruction and failure rates of ventricular catheters (VCs) used to manage hydrocephalus. METHODS: A total of 343 VCs and their associated clinical data, including patient demographics, medical history, and surgical details, were collected from 5 centers and used for this analysis. Each VC was classified by the degree of obstruction after macroscopic analysis. Univariate, multivariate, and binned analyses were conducted to test for associations between clinical data and degree of VC obstruction. RESULTS: VCs from patients with 0 to 2 lifetime revisions had a larger proportion of VC holes obstructed than VCs from patients with 10 or more revisions (p = 0.0484). VCs implanted for less than 3 months had fewer obstructed holes with protruding tissue aggregates than VCs implanted for 13 months or longer (p = 0.0225). Neither duration of implantation nor the number of lifetime revisions was a significant predictor of the degree of VC obstruction in the regression models. In the multinomial regression model, contact of the VCs with the ventricular wall robustly predicted the overall obstruction status of a VC (p = 0.005). In the mixed-effects model, the age of the patient at their first surgery emerged as a significant predictor of obstruction by protruding tissue aggregates (p = 0.002). VCs implanted through the parietal entry site were associated with more holes with nonobstructive growth and fewer empty holes than VCs implanted via other approaches (p = 0.001). CONCLUSIONS: The number of lifetime revisions and duration of implantation are correlated with the degree of VC obstruction but do not predict it. Contact of the VC with the ventricular wall and the age of the patient at their first surgery are predictors of the degree of VC obstruction, while the entry site of the VC correlates with it.

Treatment of hydrocephalus in an ovine model with an intraparenchymal stent.

OBJECTIVE: While CSF diversion is highly effective at treating hydrocephalus, shunting is unfortunately associated with a very high revision rate. Studies have demonstrated that proximal catheter obstruction is a major cause of failure. A novel proximal access device was developed, and pilot testing was performed in a sheep model of hydrocephalus. METHODS: Hydrocephalus was induced in 8 sheep using a cisternal injection of 4 ml of 25% kaolin, and the sheep were randomized to either a standard ventricular catheter or a novel intraparenchymal stent (IPS). Both groups received identical valves and distal catheters. The novel device included a 3D-printed stainless steel port and a 6 × 40-mm covered peripheral vascular stent. Animals were euthanized for signs of hydrocephalus or at a time point of 2 months. MRI was performed to determine ventricular size. Time to failure and Evans indices were compared using the Wilcoxon rank-sum test. RESULTS: All 4 experimental devices were placed without difficulty into the right lateral ventricle. There was a trend toward longer survival in the experimental group (40 vs 26 days, p = 0.24). Within the IPS group, 3 of the 4 sheep did not experience clinical symptoms of shunt failure and had an average of 37% decrease in Evans index. While 3 of 4 traditional proximal catheters demonstrated debris within the inlet holes, there was no obstructive material found in the IPSs. CONCLUSIONS: An IPS was successfully used to treat hydrocephalus in a sheep model. While statistical significance was not achieved, there were clear benefits to using a stent, including a decreased clog rate and the ability to perform a percutaneous revision. Further testing is needed to ensure efficacy and safety prior to human application.

Paediatric ventriculoperitoneal shunt failures: 12-year experience from a Singapore children's hospital.

PURPOSE: Cerebrospinal fluid (CSF) shunt failures in children are devastating. The primary aims of this study are to, firstly, review our institutional series of ventriculoperitoneal shunt (VPS) insertions and identify factors associated with shunt failure. METHODS: This is a single-institution, retrospective study conducted over a 12-year period. All patients under 18 years old with VPS inserted were included. Variables of interest such as patient characteristics, hydrocephalus aetiology, shunt implant details, and outcomes were subjected to statistical analyses. RESULTS: A total of 214 VPS patients were selected for this study. The mean age at VPS insertion was 6 months with a mean follow-up duration of 44 months. The most common type of hydrocephalus was obstructive (n = 142, 66.4%), and the most frequent aetiology was tumour-related (n = 66, 30.8%). The 30-day shunt failure rate was 9.3%: 9 infections (4.2%), 7 occlusions (3.3%), and 4 others (1.9%). After multivariable analysis, only recent central nervous system (CNS) infection prior to VPS insertion remained significant (OR 15.4 (1.3-175), p = 0.028). CONCLUSION: This is the first, large-scale local study focused on the shunt failure in Singaporean children. Significant findings in our study demonstrate that recently treated CNS infection is a factor associated with 30-day shunt failure while the values of CSF constituents were not contributory.

Comparison of outcomes in the management of abdominal pseudocyst in children with shunted hydrocephalus: a Hydrocephalus Clinical Research Network study.

OBJECTIVE: Abdominal pseudocyst (APC) can cause distal site failure in children with ventriculoperitoneal shunts and is specifically designated as an infection in Hydrocephalus Clinical Research Network (HCRN) protocols. Specific management and outcomes of children with APCs have not been reported in a multicenter study. In this study, the authors investigated the management and outcomes of APC in children with shunted hydrocephalus who were treated at centers in the HCRN. METHODS: The HCRN Registry was queried to identify children < 18 years old with shunts who were diagnosed with an APC (i.e., a loculated abdominal fluid collection containing the peritoneal catheter with abdominal distention and/or displacement of peritoneal contents). The primary outcome was shunt failure after APC treatment. The primary variable was reimplantation of the distal catheter after pseudocyst treatment back into the peritoneum versus implantation in a nonperitoneal site. Other risk factors for shunt failure after APC treatment and variability in APC management were investigated. RESULTS: Among 141 children from 14 centers who underwent first-time management of an APC over a 14-year period, the median time from previous shunt surgery to APC diagnosis was 3.8 months. Overall, 17.7% of children had a positive culture: APC cultures were positive in 14.2% and CSF cultures in 15.6%. Six other children underwent shunt revision without removal; all underwent reoperation within 1 month. There was no difference in shunt survival (log-rank test, p = 0.42) or number of subsequent revisions within 6, 12, or 24 months for shunts reimplanted in the abdomen versus those implanted in a nonperitoneal location. Nonperitoneal implantation was associated with more noninfectious revisions (42.3% vs 22.9%, p = 0.019), whereas infection was more common after reimplantation in the abdomen (25.7% vs 7.0%, p = 0.003). Univariable analysis demonstrated that younger age at APC diagnosis (8.3 vs 12.2 years, p = 0.006) and prior shunt procedure within 12 weeks of APC diagnosis (59.5% vs 40.5%, p = 0.012) were associated with shunt failure after APC treatment. Multivariable modeling confirmed that prior shunt surgery within 12 weeks of APC diagnosis was independently associated with failure (HR 1.79 [95% CI 1.04-3.07], p = 0.035). CONCLUSIONS: In the HCRN, APCs in the setting of CSF shunts are usually managed with externalization. Shunt surgery within 12 weeks of APC diagnosis was associated with risk of failure after APC treatment. Although no differences were found in overall shunt failure rate, noninfectious shunt revisions were more common in the nonperitoneal distal catheter sites, and infection was a more common reason for failure after reimplantation of the shunt in the abdomen.

Ventriculopleural shunt outcomes for pediatric hydrocephalus: a single-institution experience.

PURPOSE: The aim of this study is to analyze rates of ventriculopleural (VPL) shunt failure and complications among patients with pediatric hydrocephalus, and to analyze which factors may predict early (< 1 year) or late (> 1 year) VPL shunt failure in this sample. METHODS: A retrospective chart review was conducted of all consecutive VPL shunt placements from 2000 to 2019 at our institution. Data was collected on patient characteristics, shunt history, and shunt type. Primary endpoints include rates of VPL shunt survival and rates of symptomatic pleural effusion. The Kaplan-Meier method was used to calculate shunt survival, and Fisher's exact test and t-test were used to compare differences between categorical variables and means, respectively (p < 0.05). RESULTS: Thirty-one patients with pediatric hydrocephalus underwent VPL shunt placement (mean age 14.2 years). Of the 27 patients with long-term follow-up (mean 46 months), VPL shunt revision was required in 19, seven of which were due to pleural effusion. Overall shunt survival rates at 1, 3, 5, and 7 years were 76%, 62%, 55%, and 46%, respectively. Mean duration of shunt survival was 26.74 months. Overall pleural effusion rate was 26%. No patient-specific factors, including shunt valve type, were significantly associated with shunt survival, risk of early revision, or risk of pleural effusion. CONCLUSIONS: Our results are comparable to those reported in the literature and represent one of the largest case series on the topic. VPL shunts are a viable second-line option when ventriculoperitoneal (VP) shunt placement is not possible or desirable, though there are high rates of shunt revision and pleural effusion.

Characteristics of shunt failure in 38,095 adult shunt insertion surgeries: a systematic review and meta-analysis.

OBJECTIVE: The management of excess CSF in patients with hydrocephalus typically requires using a shunt to divert CSF. Unfortunately, there is a high rate of shunt failure despite improvements in device components and insertion techniques. Reoperation is frequently necessary, which contributes to patient harm and increased healthcare costs. While factors affecting shunt failure are well defined in the pediatric population, information regarding adults is lacking. The authors undertook a systematic review and meta-analysis to determine how shunt failure in the adult population is reported and investigated the etiologies of shunt failure. METHODS: This review is reported according to PRIMSA and utilized the MEDLINE, Embase, and Google Scholar databases. Abstracts were screened by two independent reviewers, and data were extracted in duplicate by two independent reviewers. Statistical analyses were performed using SPSS and Stata. RESULTS: The pooled rates of shunt failure were 10% (95% CI 5%-15%) in studies with a mean follow-up time of less than 1 year, 12% (95% CI 8%-14%) with a follow-up time between 1 and 2 years, and 32% in studies with a follow-up time of 2 years or greater (95% CI 19%-43%). The pooled rate of failure was 17% across all studies. The most common cause of shunt failure was obstruction at 3.0% (95% CI 2%-4%), accounting for 23.2% of shunt failures. Infection was the second most common at 2.8% (95% CI 2%-3%), accounting for 22.5% of shunt failures. The most common location of shunt failure was the distal catheter, with a failure rate of 4.0% (95% CI 3%-5%), accounting for 33.4% of shunt failures. The definition of shunt failure was heterogeneous and varied depending on institutional practices. The combination of symptoms with either CT or MRI was the most frequently reported method for assessing shunt failure. CONCLUSIONS: Important variation regarding how to define, investigate, and report shunt failure was identified. The overall shunt failure rate in adults is at least 32% after 2 years, which, while lower than that typically reported in the pediatric population, is significant. The most common causes of shunt failure in adults are infection and obstruction. The most common site of failure occurred at the distal catheter, highlighting the need to develop strategies to both report and mitigate distal shunt failure in adult shunt patients.

Ventriculoperitoneal Shunt Surgery for Hydrocephalus: One of the Common Neurosurgical Procedures and Its Related Problems.

Objective This study was conducted to assess the outcome in patients with hydrocephalus who underwent ventriculoperitoneal (VP) shunt surgery. Methods This retrospective study was conducted at the neurosurgery department of a tertiary care hospital. The time frame was three years and five months from January 2017 to May 2020 with a follow-up of six months. Results This study included 1030 patients, out of whom 64.2% were male and 35.8% were female. While the majority of the patients were more than 11 years of age (466), age did not have any significant impact on the outcome of the ventriculoperitoneal shunt surgery. The most common cause of hydrocephalus was congenital (47.6%). A good outcome was seen in 63.4%, mortality was 10.6%, and complications were identified for 25.8%. The underlying pathology had a significant impact on the outcome in our study (p-value < 0.05) where the congenital cause of hydrocephalus showed a better outcome than any other cause. Conclusion Ventriculoperitoneal shunt is a good way to manage hydrocephalus, but there is always a high risk of complications.

Endoscopic third ventriculostomy for shunt malfunction in the pediatric population: a systematic review, meta-analysis, and meta-regression analysis.

OBJECTIVE: Despite growing published evidence of the merits of endoscopic third ventriculostomy (ETV) instead of shunt revision at the time of shunt malfunction (secondary ETV), concerns about its efficacy and complications remain and ETV is still not used widely in this context. This study aimed to carry out a comprehensive meta-analysis and reports on the success and safety of secondary ETV in the pediatric age group. METHODS: In accordance with the PRISMA guidelines, systematic searches of Medline, Embase, and Cochrane Central were undertaken from database inception to September 7, 2022. ETV success was defined as the lack of need for a shunt and was the primary outcome measure. Secondary outcome measures were the rates of complications and mortality. A random-effects model was used. Summary-level meta-regression was performed to identify predictors for success in accordance with the ETV Success Score (ETVSS). RESULTS: Sixteen studies reporting on 584 patients who underwent secondary ETV for shunt malfunction were included in the meta-analysis. The overall pooled mean (95% CI) age was 6.1 (3-9) years, and 57.0% of patients were male. The pooled prevalence rates of the hydrocephalus etiologies were as follows: aqueduct stenosis (39.3%); myelomeningocele (27.6%); postinfectious (17.1%); posthemorrhagic (13.0%); neoplasm (13.0%); and malformation (11.3%). The overall pooled success rates of ETV for shunt malfunction at 3 months, 6 months, and 12 months were 65.69% (95% CI 52%-77%, prediction interval 47%-81%, I2 = 0, p = 0.775); 63.25% (95% CI 54%-72%, prediction interval 38%-83%, I2 = 65, p < 0.001); and 53.37% (95% CI 24%-81%, prediction interval 1%-99%, I2 = 47, p = 0.154). The overall pooled prevalence of intraoperative bleeding was 4.96% (95% CI 0%-64%, prediction interval 0%-99%, I2 = 85, p < 0.001). The overall rates of complications were low, with new neurological deficit (transient or permanent) having the highest rate at 1.61% (95% CI 0.68%-3.72%, prediction interval 0.67%-3.78%, I2 = 0, p > 0.999). On meta-regression, age (p = 0.138), proportion of patients with postinfectious hydrocephalus (p = 0.8736), and number of shunt revisions (p = 0.1775) were not statistically significant predictors of secondary ETV success at 6 months. CONCLUSIONS: This meta-analysis demonstrates that secondary ETV after shunt malfunction in pediatric patients is a feasible option with acceptable success rates and low complication rates. Clinical trial registration no.: CRD42022359573 (PROSPERO).

Clinical Outcome of Endoscopic Procedure in Patients with Shunt Malfunction.

OBJECTIVE: The goal of this study was to analyze the clinical outcomes of endoscopic third ventriculostomy (ETV) and endoscopic septostomy when shunt malfunction occurs in a patient who has previously undergone placement of a ventriculoperitoneal shunt. METHODS: From 2001 to 2020 at Seoul National University Children's Hospital, patients who underwent ETV or endoscopic septostomy for shunt malfunction were retrospectively analyzed. Initial diagnosis (etiology of hydrocephalus), age at first shunt insertion, age at endoscopic procedure, magnetic resonance or computed tomography image, subsequent shunting data, and follow-up period were included. RESULTS: Thirty-six patients were included in this retrospective study. Twenty-nine patients, 18 males and 11 females, with shunt malfunction underwent ETV. At the time of shunting, the age ranged from 1 day to 15.4 years (mean, 2.4 years). The mean age at the time of ETV was 13.1 years (range, 0.7 to 29.6 years). Nineteen patients remained shunt revision free. The 5-year shunt revisionfree survival rate was 69% (95% confidence interval [CI], 0.54-0.88). Seven patients, three males and four females, with shunt malfunction underwent endoscopic septostomy. At the time of shunting, the age ranged from 0.2 to 12 years (mean, 3.9 years). The mean age at the time of endoscopic septostomy was 11.9 years (range, 0.5 to 29.5 years). Four patients remained free of shunt revision or addition. The 5-year shunt revision-free survival rate was 57% (95% CI, 0.3-1.0). There were no complications associated with the endoscopic procedures. CONCLUSION: The results of our study demonstrate that ETV or endoscopic septostomy can be effective and safe in patients with shunt malfunction.

Escape from prism.

A 14-year-old boy with a history of shunted congenital hydrocephalus began having headaches with nausea and vomiting after transcontinental flights. He gradually developed horizontal diplopia indicative of mild bilateral sixth nerve palsy, without papilledema or ventriculomegaly. Intracranial pressure monitoring showed no signs of elevation. After he subsequently developed papilledema, surgical exploration showed shunt malfunction, and shunt replacement produced rapid resolution of symptoms. This case demonstrates the importance of relying on clinical history and neuro-ophthalmologic examination in patients with hydrocephalus and suspected shunt failure, even when objective confirmatory evidence of intracranial pressure elevation is lacking.

Preoperative nomogram predicting ventriculoperitoneal shunt longevity after initial shunt failure.

Background and objectives: Initial shunt failure following ventriculoperitoneal (VP) shunt surgery has a significant impact on the working time of the shunt. However, there are few studies regarding factors affecting VP shunt longevity. Hence, in this study, we aimed to build a nomogram to predict the longevity of the replacement VP shunt in patients with initial shunt failure. Methods: From 2011 to 2021, 142 patients with initial VP failure who underwent VP shunt revision were enrolled and relevant clinical and demographic factors were analyzed. Univariate and multivariate Cox proportional hazard regression models were used to choose predictors, and a nomogram was constructed using nine independent prognostic variables: sex, age, hydrocephalus type, intensive care unit admission, tracheostomy, decompressive craniectomy, craniotomy, lumbar cisterna drainage, and ventricular drainage. The prediction models' discrimination, accuracy, calibration, and clinical value were evaluated using Harrell's C-index, a calibration plot, and decision curve analysis. Results: At 1 month, 3 months, and 5 years, the nomogram's C-index was 0.680, 0.708, and 0.694, respectively. The nomogram's calibration plot provided a good fit for the overall prediction over the course of 1 year. Decision curve analysis predicted that 1-3 months after surgery will yield good net benefits between 30 and 50% probability thresholds. Conclusion: A preoperative nomogram may be an effective tool for assessing VP shunt longevity after initial VP shunt placement.

Partial Obstruction of Ventricular Catheters Affects Performance in a New Catheter Obstruction Model of Hydrocephalus.

OBJECTIVE: One of the major causes of cerebral ventricular shunt failure is proximal catheter occlusion. We describe a novel ventricular cerebrospinal fluid (CSF) flow replicating system that assesses pressure and flow responses to varying degrees of catheter occlusion. METHODS: Ventricular catheter performance was assessed during conditions of partial and complete occlusion. The catheters were placed into a three-dimensionally-printed phantom ventricular replicating system. Artificial CSF was pumped through the ventricular system at a constant rate of 1 mL/min to mimic CSF flow, with the proximal end of the catheter in the phantom ventricle. Pressure transducer and flow rate sensors were used to measure intra-phantom pressure, outflow pressure, and CSF flow rates. The catheters were also inserted into silicone tubing and pressure was measured in the same manner for comparison with the phantom. RESULTS: Pressure measured in the ventricle phantom did not change when the outflow of the ventricular catheter was partially occluded. However, the intraventricular phantom pressure significantly increased when the outflow catheter was 100% occluded. The flow through the catheter showed no significant difference in rate with any degree of partial occlusion of the catheter. At the distal end of the partially occluded catheters, there was less pressure compared with the nonoccluded catheters. This difference in pressure in partially occluded catheters correlated with the percentage of catheter hole occlusion. CONCLUSIONS: Our model mimics the physiological dynamics of the CSF flow in partially and completely obstructed ventricular catheters. We found that partial occlusion of the catheter had no effect on the CSF flow rate, but did reduce outflow pressure from the catheter.