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.

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.

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.

Prediction of shunt failure facilitated by rapid and accurate volumetric analysis: a single institution's preliminary experience.

BACKGROUND: Shunt malfunction is a common complication and often presents with hydrocephalus. While the diagnosis is often supported by radiographic studies, subtle changes in CSF volume may not be detectable on routine evaluation. The purpose of this study was to develop a novel automated volumetric software for evaluation of shunt failure in pediatric patients, especially in patients who may not manifest a significant change in their ventricular size. METHODS: A single-institution retrospective review of shunted patients was conducted. Ventricular volume measurements were performed using manual and automated methods by three independent analysts. Manual measurements were produced using OsiriX software, whereas automated measurements were produced using the proprietary software. A p value < 0.05 was considered statistically significant. RESULTS: Twenty-two patients met the inclusion criteria (13 males, 9 females). Mean age of the cohort was 4.9 years (range 0.1-18 years). Average measured CSF volume was similar between the manual and automated methods (169.8 mL vs 172.5 mL, p = 0.56). However, the average time to generate results was significantly shorter with the automated algorithm compared to the manual method (2244 s vs 38.3 s, p < 0.01). In 3/5 symptomatic patients whose neuroimaging was interpreted as stable, the novel algorithm detected the otherwise radiographically undetectable CSF volume changes. CONCLUSION: The automated software accurately measures the ventricular volumes in pediatric patients with hydrocephalus. The application of this technology is valuable in patients who present clinically without obvious radiographic changes. Future studies with larger cohorts are needed to validate our preliminary findings and further assess the utility of this technology.

In vitro testing of explanted shunt valves in hydrocephalic patients with suspected valve malfunction.

Diagnosis of symptomatic valve malfunction in hydrocephalic patients treated with VP-Shunt (VPS) might be difficult. Clinical symptoms such as headache or nausea are nonspecific, hence cerebrospinal fluid (CSF) over- or underdrainage can only be suspected but not proven. Knowledge concerning valve malfunction is still limited. We aim to provide data on the flow characteristics of explanted shunt valves in patients with suspected valve malfunction. An in vitro shunt laboratory setup was used to analyze the explanted valves under conditions similar to those in an implanted VPS. The differential pressure (DP) of the valve was adjusted stepwise to 20, 10, 6, and 4 cmH2O. The flow rate of the explanted and the regular flow rate of an identical reference valve were evaluated at the respective DPs. Twelve valves of different types (Codman CertasPlus valve n = 3, Miethke Shuntassistant valve n = 4, Codman Hakim programmable valve n = 3, DP component of Miethke proGAV 2.0 valve n = 2) from eight hydrocephalic patients (four male), in whom valve malfunction was assumed between 2016 and 2017, were replaced with a new valve. Four patients suffered from idiopathic normal pressure (iNPH), three patients from malresorptive and one patient from obstructive hydrocephalus. Post-hoc analysis revealed a significant difference (p < 0.001) of the flow rate between each explanted valve and their corresponding reference valve, at each DP. In all patients, significant alterations of flow rates were demonstrated, verifying a valve malfunction, which could not be objectified by the diagnostic tools used in the clinical routine. In cases with obscure clinical VPS insufficiency, valve deficiency should be considered.

Long-term risk of shunt failure after brain tumor surgery.

Long-term risks and survival times of ventriculoperitoneal (VP) shunts implanted due to hydrocephalus (HC) after craniotomy for brain tumors are largely unknown. The aim of this study was to establish the overall VP shunt survival rates during a decade after shunt insertion and to determine risks of shunt failure after brain tumor surgery in the long-term period. In this population-based cohort from a well-defined geographical region, all adult patients (> 18 years) from 2004 to 2013 who underwent craniotomies for intracranial tumors leading to VP shunt dependency were included. Our brain tumor database was cross-linked to procedure codes for shunt surgery (codes AAF) to extract brain tumor patients who became VP shunt dependent after craniotomy. The VP shunt survival time, i.e. the shunt longevity, was calculated from the day of shunt insertion after brain tumor surgery until the day of its failure. A total of 4174 patients underwent craniotomies, of whom 85 became VP shunt dependent (2%) afterwards. Twenty-eight patients (33%) had one or more shunt failures during their long-term follow-up, yielding 1-, 5-, and 10-year shunt success rates of 77%, 71%, and 67%, respectively. Patient age, sex, tumor location, primary/repeat craniotomy, placement of external ventricular drainage (EVD), ventricular entry, post-craniotomy hemorrhage, post-shunting meningitis/infection, and multiple shunt revisions were not statistically significant risk factors for shunt failure. Median shunt longevity was 457.5 days and 21.5 days for those with and without pre-craniotomy HC, respectively (p < 0.01). This study can serve as benchmark for future studies.

Cerebrospinal fluid hydrocephalus shunting: cisterna magna, ventricular frontal, ventricular occipital.

Despite advances in cerebrospinal fluid shunting technology, complications remain a significant concern. There are some contradictions about the effectiveness of proximal catheter entry sites that decrease shunt failures. We aim to compare efficiency of shunts with ventricular frontal, ventricular occipital, and cisterna magna entry sites. The systemic search was conducted in the database from conception to February 16, 2022 following guidelines of PRISMA. Between 2860 identified articles, 24 articles including 6094 patients were used for data synthesis. The aggregated results of all patients showed that "overall shunt failure rate per year" in mixed hydrocephalus with ventricular frontal and occipital shunts, and cisterna magna shunt (CMS) were 9.0%, 12.6%, and 30.7%, respectively. The corresponding values for "shunt failure rate" due to obstruction were 15.3%, 31.5%, and 10.2%, respectively. The similar results for "shunt failure rate" due to infection were 11.3%, 9.1%, and 27.2%, respectively. The related values for "shunt failure rate" due to overdrainage were 2.9%, 3.9%, and 13.6%, respectively. CMS was successful in the immediate resolution of clinical symptoms. Shunting through an occipital entry site had a greater likelihood of inaccurate catheter placement and location. Contrary to possible shunt failure due to overdrainage, the failure likelihood due to obstruction and infection in pediatric patients was higher than that of mixed hydrocephalus patients. In both mixed and pediatric hydrocephalus, obstruction and overdrainage were the most and least common complications of ventricular frontal and occipital shunts, respectively. The most and least common complications of mixed CMS were infection and obstruction, respectively.

Machine learning predicts risk of cerebrospinal fluid shunt failure in children: a study from the hydrocephalus clinical research network.

PURPOSE: While conventional statistical approaches have been used to identify risk factors for cerebrospinal fluid (CSF) shunt failure, these methods may not fully capture the complex contribution of clinical, radiologic, surgical, and shunt-specific variables influencing this outcome. Using prospectively collected data from the Hydrocephalus Clinical Research Network (HCRN) patient registry, we applied machine learning (ML) approaches to create a predictive model of CSF shunt failure. METHODS: Pediatric patients (age < 19 years) undergoing first-time CSF shunt placement at six HCRN centers were included. CSF shunt failure was defined as a composite outcome including requirement for shunt revision, endoscopic third ventriculostomy, or shunt infection within 5 years of initial surgery. Performance of conventional statistical and 4 ML models were compared. RESULTS: Our cohort consisted of 1036 children undergoing CSF shunt placement, of whom 344 (33.2%) experienced shunt failure. Thirty-eight clinical, radiologic, surgical, and shunt-design variables were included in the ML analyses. Of all ML algorithms tested, the artificial neural network (ANN) had the strongest performance with an area under the receiver operator curve (AUC) of 0.71. The ANN had a specificity of 90% and a sensitivity of 68%, meaning that the ANN can effectively rule-in patients most likely to experience CSF shunt failure (i.e., high specificity) and moderately effective as a tool to rule-out patients at high risk of CSF shunt failure (i.e., moderately sensitive). The ANN was independently validated in 155 patients (prospectively collected, retrospectively analyzed). CONCLUSION: These data suggest that the ANN, or future iterations thereof, can provide an evidence-based tool to assist in prognostication and patient-counseling immediately after CSF shunt placement.

Sheath formation around peritoneal tube: possible explanation for unknown cause of ventriculoperitoneal shunt failure.

Ventriculoperitoneal (VP) shunt failures are common and are frequently associated with an obstruction of the peritoneal tube. This study aimed to explore the possible causes of peritoneal tube obstruction, which are largely unknown. From January 1981 to June 2018, we performed VP shunting in 646 patients with hydrocephalus. Among the procedures performed, 148 shunt revision procedures were performed in 98 patients with VP shunt failure. Of the study participants, 64 (43.2%) patients were diagnosed with peritoneal tube obstruction and five patients developed sheath formation that obstructed the end of the peritoneal tubes. Sheath formation around the peritoneal tube is a possible cause of VP shunt dysfunction.

Changes of third ventricle diameter (TVD) mirror changes of the entire ventricular system at acute shunt failure and after shunt revision in pediatric hydrocephalus.

PURPOSE: In hydrocephalic children, regular investigations of the ventricles are important for initial diagnosis and after initial treatment. Our recent study showed that changes of the third ventricle diameter (TVD) reliably reflect changes of the entire ventricular system at diagnosis and following initial therapy. This study compares changes of TVD with changes of ventricle indices at acute shunt failure and after shunt revision in hydrocephalic children. METHODS: A total of 117 children with hydrocephalus were included in this study. MRI/CT images of 30 children were evaluated at the time of acute shunt dysfunction and after subsequent shunt revision. Measurements included axial TVD and three standard measures of lateral ventricles (Evans index, frontal occipital horn ratio (FOHR), and cella media index (CMI)). In 97 children, correlation between axial and coronal/diagonal TVD was evaluated at the time of initial diagnosis of hydrocephalus. RESULTS: At acute shunt dysfunction, the best linear correlation was found between TVD and CMI (r = 0.702, p < 0.01). Changes of TVD correlated very well to changes of FOHR (r = 0.74, p < 0.01) after shunt revision. The correlation between axial and coronal/diagonal TVD was outstanding (r = 0.995, p < 0.01). CONCLUSION: TVD showed a significant correlation with all lateral ventricle indices at acute shunt dysfunction and after shunt revision. It is therefore not only an excellent mirror of ventricular changes at initial hydrocephalus diagnosis and therapy, but it can also reliably reflect changes of the ventricular system in relevant clinical situations associated with the lifelong treatment of pediatric hydrocephalus.

A good choice for the patients with prior failed ventriculoperitoneal shunt treatment of suprasellar arachnoid cysts: endoscopic fenestration.

To investigate the effectiveness of endoscopic fenestration in the patients with prior failed ventriculoperitoneal (VP) shunt treatment of suprasellar arachnoid cysts (SACs). Between 2012 and 2018, four pediatric patients of SACs with previous failed VP shunt treatment were surgically treated using endoscopic ventriculocystocisternostomy (VCC) in our hospital. The clinical symptoms, imaging data, and surgical outcomes were collected and analyzed retrospectively. A literature review is provided with regard to the reasons of shunt failure and surgical outcome of further endoscopic fenestration in the previously reported patients of SACs with prior failed VP shunt. For the 4 cases, the initial clinical symptoms relieved or even disappeared after shunt placement, but, respectively, recurred 2, 6, 11, and 6 months later. MR scans were conducted when the clinical symptoms reappeared and showed a cyst had greatly enlarged after shunt placement. Furthermore, VP shunt-related slit ventricle was also demonstrated in 3 cases. Clinical improvement and cysts shrinkage occurred in all 4 patients after VCC. Slit ventricle and hydrocephalus were also resolved. Three patients had their shunt apparatus removed after VCC, and another patient's guardian refused to remove the shunt apparatus. Subdural hematoma occurred in one case after shunt apparatus removal. Four patients have been stable during follow-up period (mean follow-up 26.5 months). All the three patients whose VP shunt were removed were shunt independence. There were 24 patients who underwent endoscopic fenestration as an alternative to the failed VP shunt treatment in the published reports. Added our 4 patients to the published group, the effective rate of endoscopic fenestration for SACs following previous failed VP shunt treatment was approximately 93% (26/28). Of the 24 patients, the shunt apparatuses were in situ or reimplantation in 9 patients due to shunt dependence. The correction to recognize the SAC is the first condition to select the optimal management philosophy. The analysis of the series suggests endoscopic operation is still an effective and safe option in the SAC patients with previous failed VP shunt, and the shunt apparatus can be removed for some patients. The short interval time between shunt operation and endoscopic fenestration is conductive to return patients to the shunt-free state.

The ventriculo-cholecystic shunt: does CSF volume matter?

INTRODUCTION: The management of hydrocephalus in paediatric patients where the peritoneum has failed can be challenging. One option is to perform a ventriculo-cholecystic shunt. However, little is known about the capacity of the gall bladder to accommodate cerebrospinal fluid (CSF). METHODS: A retrospective case series was performed to include all paediatric patients who received a ventriculo-cholecystic shunt at a single centre, Sheffield Children's Hospital. RESULTS: We identified three patients who had a ventriculo-cholecystic shunt inserted. The shunt survived past 1 year in two patients, who had pre-operative external ventricular drain (EVD) outputs of 8 and 10 ml/h respectively. One patient shunt failed at day four post-op due to distal dysfunction, his pre-operative EVD was over 30 ml/h. CONCLUSIONS: When considering a patient for a ventriculo-cholecystic shunt, caution should be taken if a high CSF output is known, for example, as per an EVD measurement.

One year failure rates for de-novo ventriculo-peritoneal shunts in under 3-month-old children.

Introduction: Ventriculo-peritoneal shunts (VPS) are still the mainstay treatment for hydrocephalus in children. It is generally accepted that VPS failure and infection rates are higher for neonates than for older children. We compared our 1-year failure and infection rates in under 3-month-old children compared with older children in our department. Results: We identified 58 children under 3 months of age who underwent VPS insertion between January 2007 and December 2016. They had a 29.3% (17) shunt failure rate over the first year. There were two confirmed shunt infections (3.4%). Discussion: The 1-year shunt failure rate at our institution for VPS insertion in children over 3 months is 26.1% and the infection rate is 4.3% (9). The literature suggests that the outcome for VPS in younger children is worse than for older children. Our work shows similar outcomes for all children compared to those under 3 months at time of VPS insertion alone. Conclusion: Children under 3-months-old undergoing VPS insertion should not automatically expect an increased 1-year failure or infection rate compared with older children. The reasons for this may be as a result of increased subspecialisation, the more widespread use of antibiotic-impregnated catheters and improved neonatal care.

Ultrasound-guided placement of ventricular catheters in first-time pediatric VP shunt surgery.

PURPOSE: Ventriculo-peritoneal (VP) shunts are effective for treatment of hydrocephalus in all age groups; however, they are associated with complications, a common one being ventricular catheter (VC) obstruction. VC position is likely to influence VC survival; however, most VCs are positioned freehand without guidance. This paper describes the accuracy of ultrasound guidance for VC placement and the impact of tip location on VC occlusion rate. METHODS: This is a retrospective cohort study of hydrocephalic children with first-time VP shunt and ultrasound-guided VC placement. Data recorded were age, sex, cause of hydrocephalus, side (left or right) and location (frontal or occipital) of VC, and exact postoperative position within the ventricle on first postoperative imaging: middle of ventricle (optimal position), near or touching the medial or lateral ventricle wall, within the third ventricle, and at the contralateral side. RESULTS: Of the 128 screened patients, 85 had a first postoperative imaging that clearly defined the VC position and were included. The follow-up was at least 12 months. Seventy-three percent of VCs were placed on the right and 71% via a frontal burhole. Eighty-three of 85 VC tips (95%) were in the intended ventricle, 61% at optimal position. Nine of 85 VCs (10%) obstructed within the first 12 months. Seven of nine (78%) obstructed VCs were located in a nonoptimal position (p = 0.016). Two of nine (22%) obstructed VCs entered through a frontal and seven of nine (78%) through an occipital burrhole (p = 0.016). CONCLUSION: Ultrasound-guided VC placement is as precise as frameless navigated placement. The optimal VC position was associated to a significant lower VC obstruction rate. The frontal position was superior to the occipital. Intraoperative US guidance is fast with almost no extra time and no extra cost. US-guided VC placement should become standard of care in VP shunt surgery.

Risk Factors for Failure of Systemic-to-Pulmonary Artery Shunts in Biventricular Circulation.

Systemic-to-pulmonary artery shunt placement is an established palliative procedure for congenital heart disease, but it is associated with high morbidity and mortality. Data of all patients with biventricular circulation who underwent systemic-to-pulmonary artery shunt implantation between 2000 and 2016 were reviewed. Endpoints of the study were shunt failure and shunt-related mortality. Shunt failure was defined as any shunt dysfunction requiring intervention or reoperation. Shunt-related mortality was defined as death due to shunt dysfunction. A total of 217 shunts (central shunt, n = 131, Blalock-Taussig shunt, n = 86) were implanted in 178 patients. The median age of the patients was 98 days [1 day to 1.2 years]. Corrective surgery was performed at a median time of 0.6 years [3 months to 7 years] after shunt placement. Shunt failure was diagnosed in 21 patients (9.6%) at a median time of 14.6 days [0 days to 2 years]. Causes of shunt failure were stenosis (n = 11; 5%) and thrombosis (n = 10; 4.6%). The rate of freedom from shunt failure was 89.9 ± 2.6% at 1 year, the rate of shunt-related mortality was 3% (n = 5), and the rate of freedom from shunt-related mortality at 1 year was 97.5 ± 1%. Platelet transfusion was required in 43 patients (20%), all for postoperative thrombocytopenia. Perioperative platelet transfusion (p = 0.03) and shunt size of 3 mm (p = 0.03) were identified as risk factors for shunt failure. Shunt size of 3 mm was also identified as a risk factor for shunt-related mortality. The ideal shunt size in patients with biventricular circulation requiring a systemic-to-pulmonary artery shunt is 3.5 mm or larger. Platelet transfusion increases the risk of shunt failure and should be avoided. Type of shunt and diagnosis have no influence on morbidity or mortality after shunt placement.

Intra-catheter endoscopy for various shunting procedures-a retrospective analysis on surgical practicability, catheter placement, and failure rates.

BACKGROUND: The long-term function of a cerebral shunt is directly influenced by the placement of the ventricle catheter. In this work, an intra-luminal endoscope for best possible catheter positioning was used. Practicability, postoperative imaging, and shunt failure rates were retrospectively evaluated. METHODS: Between January 2012 and June 2016, an intra-catheter endoscope was applied in 71 procedures. Endoscopic technique was used for catheter placement in first-time shunting or cerebrospinal fluid reservoir insertion (n = 38), revision surgery in proximal shunt failure (n = 13), and various intraventricular stenting procedures (n = 20). Catheter positioning was graded on postoperative imaging using a four-point scale. All patients were regularly followed up (mean, 31.6 months) to recognize shunt failures. RESULTS: Endoscopic application could be completed as intended in 68 of 71 procedures. Postoperative imaging could exclude complete misplacement of all catheters, but optimal positioning was only achieved in 64.7% (44/68 cases). Four catheters had to be revised due to malfunction (failure rate, 5.8%). Another five catheters had to be removed due to infectious complications or wound-healing disorders. Direct correlations between catheter complications and suboptimal catheter positioning were not seen. Slit or distorted ventricles also did not prove to be a risk factor for the observed complications. CONCLUSIONS: Versatile application possibilities of the intra-catheter endoscope reflect the advantages of the technique. Independent of the performed procedure, unintended positionings or even complete catheter misplacements could be avoided. However, in more than one-third of all cases, suboptimal catheter placements became obvious. Interestingly, negative influences on later shunt failures were not seen.

Shunt age-related complications in adult patients with suspected shunt dysfunction. A recommended diagnostic workup.

BACKGROUND: Patients admitted for suspicion of shunt dysfunction (SD) often show unspecific symptoms and require time-consuming, expensive and even invasive diagnostics involving significant radiation exposure. The purpose of this retrospective study was to analyse the current diagnostic procedures and to propose a process optimisation. METHOD: As all patients admitted for suspicion of SD receive imaging studies, we searched for adult patients receiving neuroimaging in the period from January 2010 to July 2013, analysing referring diagnosis, clinical signs, products, diagnostic process and final diagnosis. Recursive partitioning was used to define time intervals for differentiating types of SD. RESULTS: A total of 148 patients, aged 18-89 (mean, 54) years, were studied. Forty-two percent were referred by a hospital or rehabilitation centre, 30% by general practitioners and 24% were self-referrals. The admission diagnosis was in the majority "shunt dysfunction" only. Further differentiations were rarely made. An SD was confirmed in 46% of the patients. In 17%, the symptoms were based on another cause and in 37% they could not be clearly attributed to any specific disorder. Abdominal dislocations (2%) and shunt infections (5%) were found within the first 6 months. Over- (3%) and under-drainage (14%) were the most frequent complications during the first 4 years. Disconnections (13%) occurred generally 4 years or more after implantation. Only shunt obstruction (9%) showed no temporal pattern. CONCLUSIONS: Symptoms of SD remain mostly unspecific. This study showed that the type of SD depends on the time interval from implantation. We propose a workup strategy for patients with SD based on the temporal profile.

Efficacy of an Extracellular Matrix in Systemic Loading Conditions in Congenital Heart Surgery.

Extracellular matrices (ECM) are commonly used to repair congenital heart defects; however, there is a lack of literature pertaining to outcomes with ECM use in high-pressure conditions. Between 2011 and 2014, a total of 202 patients underwent congenital heart disease repair using the ECM placed in a systemic pressure condition. The operative sites included: defects in the ventricular septum, mitral valve, aortic valve, ascending aorta, and aortic arch. Patients were followed and evaluated for mortality and reoperations due to loss of ECM integrity. Echocardiograms were evaluated for graft malfunction such as aneurysmal dilation, VSD formation, valve malfunction, or outflow tract obstruction. Patients were followed for an average of 1492 days (Median = 1583). Out of the 202 patients, 7 (3.5%) died due to complications unrelated to ECM, and 10 (5%) underwent reoperations due to complications of ECM integrity. Reoperations were as follows: two of 6 patients receiving aortic leaflet replacement required reoperation for leaflet failure; four of 12 patients receiving mitral valve leaflet repairs required reoperation for leaflet failure; and four of 142 patients with VSD repair required reoperation for residual shunting. The average time to reoperation was 208 days. There were no outflow tract obstructions or aneurysmal dilatations observed. This modern case series suggests that the ECM is efficacious and sustainable under systemic conditions in congenital heart defect repair. However, concerns remain about the use of ECM in aortic valve repair and infant mitral valve repair. Further studies are needed to evaluate long-term ECM integrity.