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Cerebrospinal fluid (CSF) bathing the central nervous system is produced by brain and choroid plexus within the ventricles for re-absorption into the venous circulation through arachnoid granulations (AG). Communicating hydrocephalus results from disruption of the absorptive process, necessitating surgical catheter-based shunt placement to relieve excess pressure from CSF buildup. Adjustable valve designs and antibiotic impregnation have minimally impacted persistent failure rates and postoperative complications. To confront this challenge, we have developed an innovative endovascular shunt implant biologically inspired from AG function to restore the natural dynamics of CSF drainage while concurrently addressing the predominant factors contributing to conventional shunt malfunction., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background:  Ventricular catheter (VC) placement in the selected subset of adult hydrocephalus can be highly challenging due to abnormal anatomical configuration or the need for trans-aqueductal stent placement. Transluminal endoscopy with the ShuntScope has been invented to increase the success rate of catheter placement. This study evaluates the image qualities of ShuntScope and related surgical outcomes in adults., Methods:  A retrospective analysis of all adult patients undergoing VC placement using the ShuntScope from November 2011 to July 2022 in the authors' department was performed. Demographic, clinical, and radiologic data were evaluated. The visualization quality of the intraoperative endoscopy was stratified into excellent, medium, and poor, and compared to the postoperative catheter tip placement. Follow-up evaluation included the surgical revision rate due to proximal catheter misplacement., Results:  A total of 63 ShuntScope-assisted surgeries have been performed on 60 adults. The mean age of the patients was 48.43 years. The most common underlying pathology was a tumor- or cyst-related cerebrospinal fluid (CSF) impairment in 38.33%, followed by a pseudotumor cerebri in 21.66%. The achieved image quality was excellent in 39.68%, medium in 47.62%, and poor in 12.7%. Ideal catheter placement was achieved in 79.37%. There were no intraoperative complications associated with the use of the ShuntScope. The revision rate due to suboptimal proximal VC placement was 4.76% during a mean follow-up period of 27.75 months. A statistical correlation between the image quality and accuracy of the catheter position was observed ( p  < 0.001)., Conclusion:  The ShuntScope can be considered an important addition to standard surgical tools in treating a selected subset of adult hydrocephalus. Direct visualization might even help achieve correct placement of the catheter in the cases with blurred vision and limited visual overview., Competing Interests: Joachim Oertel acted as consultant to Karl Storz Company until 2020., (Thieme. All rights reserved.)

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.

This brief report aimed to show the utility of photon-counting technology alongside standard cranial imaging protocols for visualizing shunt valves in a patient's cranial computed tomography scan. Photon-counting CT scans with cranial protocols were retrospectively surveyed and four types of shunt valves were encountered: proGAV 2.0 ® , M.blue ® , Codman Certas ® , and proSA ® . These scans were compared with those obtained from non-photon-counting scanners at different time points for the same patients. The analysis of these findings demonstrated the usefulness of photon-counting technology for the clear and precise visualization of shunt valves without any additional radiation or special reconstruction patterns. The enhanced utility of photon-counting is highlighted by providing superior spatial resolution compared to other CT detectors. This technology facilitates a more accurate characterization of shunt valves and may support the detection of subtle abnormalities and a precise assessment of shunt valves.

Cerebrospinal fluid (CSF) shunting is an established long-term treatment option for hydrocephalus, and is one of the most commonly performed neurosurgical procedures in western countries.Despite advances in CSF shunt design and management, its failure rates remain high and is most commonly due to obstruction and infection.Cerebrospinal fluidshunt failure diagnosis should be prompt and accurate in establishing timely if its revision is appropriate. Radionuclide shuntography with technetium-99m-diethylenetriaminepetaacetic acid ( 99m Tc-DTPA) is a useful technique for evaluation CSF shunts and management of patients presenting with shunt-related problems, in particular it can avoid unnecessary replacement interventions. Although its execution and interpretation require specific skills, we suggest its execution for the evaluation of device's patency. We here describe the radionuclide shuntography performed with recent hybrid multimodal technologies, with a procedure customized to a complicated patient with hydrocefalus and neoplastic disease. We suggest considering radionuclide shuntography in association with conventional imaging and strongly recommend the additional performance of single photon emission computed tomography/computed tomography (SPECT/CT) because it also provides valuable information to complete the interpretation of planar images.

Objective: The quantity of ultra-high field MRI neuroimaging studies has rapidly increased. This study tests function, safety, and image artifacts of two frequently implanted programmable ventriculo-peritoneal (VP) shunt valves in a 7T MRI system., Methods: All tests were performed using a whole-body 7T MRI system. Three proGAV 2.0 and 3 CODMAN CERTAS® Plus programmable VP-shunt valves were tested in three steps. 1) Deflection angle tests close to the bore opening at the location of a static magnetic field gradient of 3-5 T/m. 2) Valves were fixed on a spherical phantom in 3 positions (a. lateral, b. cranial, c. cranial with 22.5° tilt anteriorly) and assessed for keeping the programmed pressure setting and reprogrammability. 3) Valves were fixed on the phantom and positioned lateral in a radiofrequency head coil. MRI scans were performed for both models, including MPRAGE, GRE and SE sequences., Results: Deflection angles were moderate (13°, 14°, 13°) for the proGAV valves and close to critical (43°, 43°, 41°) for the CODMAN valves at the test location. Taking a scaling factor of 2-3 for the maximum spatial magnetic field gradient accessible to a patient within the magnet bore into account renders both valves MR unsafe regarding ferromagnetic attraction. The proGAV valves kept the pressure settings in all positions and were reprogrammable in positions a. and b. In position c., reprogrammability was lost. The CODMAN valves changed their pressure setting and reprogrammability was lost in all positions. MR image signal homogeneity was unaltered in the phantom center, artifacts limit the assessability of structures in close vicinity to the valves., Conclusion: Both tested programmable VP-shunt valves are MR unsafe for 7T systems. Novel programming mechanisms using permanent magnets with sufficient magnetic coercivity or magnet-free mechanisms may allow the development of programmable VP-shunt valves that are conditional for 7T MR systems., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Chen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

In this article, we aimed to describe some of the currently most challenging problems in neurosurgical management of hydrocephalus and how these can be reasons for inspiration for and development of research. We chose 4 areas of focus: 2 dedicated to improvement of current treatments (shunt implant surgery and endoscopic hydrocephalus surgery) and 2 dedicated to emerging future treatment principles (molecular mechanisms of cerebrospinal fluid secretion and hydrocephalus genetics)., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: External magnetic forces can have an impact on programmable valve mechanisms and potentially alter the opening pressure. As wearable technology has begun to permeate mainstream living, there is a clear need to provide information regarding safety of these devices for use near a programmable valve (PV). The aim of this study was to evaluate the magnetic fields of reference devices using smartphone-integrated magnetometers and compare the results with published shunt tolerances., Methods: Five smartphones from different manufacturers were used to evaluate the magnetic properties of various commonly used (n = 6) and newer-generation (n = 10) devices using measurements generated from the internal smartphone magnetometers. PV tolerance testing using calibrated magnets of varying field strengths was also performed by smartphone magnetometers., Results: All tested smartphone-integrated magnetometers had a factory sensor saturation point at around 5000 µT or 50 Gauss (G). This is well below the threshold at which a magnet can potentially deprogram a shunt, based on manufacturer reports as well as the authors' experimental data with a threshold of more than 300 G. While many of the devices did saturate the smartphone sensors at the source, the magnetic flux density of the objects decreases significantly at 2 inches., Conclusions: The existence of an upper limit on the magnetometers of all the smartphones used, although well below the published deprogramming threshold for modern programmable valves, does not allow us to give precise recommendations on those devices that saturate the sensor. Based on the authors' experimental data using smartphone-integrated magnetometers, they concluded that devices that measure < 40 G can be used safely close to a PV.

Objective: CSF shunts are the most common procedures performed in the pediatric neurosurgical population. Despite attempts in multiple studies, a superior shunt valve has never been shown. Because of this, the authors aim was to examine the impact of shunt valve standardization at their institution to determine if there is a difference in surgical cost, operative time, or short-term postoperative shunt failure., Methods: A retrospective analysis at the authors' institution was performed for all new CSF diversion shunts, as well as shunt revisions requiring a new valve, or a new valve and at least a new proximal or distal catheter over a 1-year period (January 1, 2016, to December 31, 2016). After a period of transition, neurosurgeons were encouraged to use only one type of fixed-differential-pressure valve and one type of programmable valve when performing shunt surgeries. These patients who underwent "standardized" shunt surgery over a 1-year period (January 1, 2018, to December 31, 2018) were then compared to patients in the prestandardization epoch. All patients were followed for a 12-month period after surgery. Demographic information, surgical cost, operative time, and postoperative shunt failure data were collected in all patients in the study., Results: The authors analyzed 87 shunt surgeries in patients prior to standardization and 94 shunt surgeries in patients after standardization. The rate of violation of the standardized shunt valve policy after implementation was 5.3% (5 of 94 procedures). When comparing the prestandardization group to those who received the standardized valve, operative costs were less ($1821.04 vs $1333.75, p = 0.0034). There was no difference in operative times between groups (78 minutes vs 81 minutes, p = 0.5501). There was no difference in total number of shunt failures between the two groups at 12 months after surgery (p = 0.0859). The rate of postoperative infection was consistent with the literature at 8%., Conclusions: In accordance with quality improvement principles, the reduction of unexplained clinical variance invariably leads to a decrease in cost and, more importantly, increased value. In this study, the implementation of a standardized shunt valve decreased operative cost. There were no differences in postoperative shunt failures at 12 months after surgery and no differences in length of surgery. Standardizing shunt valves in the treatment of pediatric hydrocephalus seems to be cost-effective and safe.

Background: Hydrocephalus is managed by surgically implanting flow-diversion technologies such as differential pressure valves and antisiphoning devices; however, such hardware is prone to failure. Extensive research has tested them in flow-controlled settings using saline or de-aerated water, yet little has been done to validate their performance in a setting recreating physiologically relevant parameters, including intracranial pressures, cerebrospinal fluid (CSF) protein content, and body position., Objective: To more accurately chart the episodic drainage characteristics of flow-diversion technology. A gravity-driven benchtop model of flow was designed and tested continuously during weeks-long trials., Methods: Using a hydrostatic pressure gradient as the sole driving force, interval flow rates of 6 valves were examined in parallel with various fluids. Daily trials in the upright and supine positions were run with fluid output collected from distal catheters placed at alternating heights for extended intervals., Results: Significant variability in flow rates was observed, both within specific individual valves across different trials and among multiple valves of the same type. These intervalve and intravalve variabilities were greatest during supine trials and with increased protein. None of the valves showed evidence of overt obstruction during 30 d of exposure to CSF containing 5 g/L protein., Conclusion: Day-to-day variability of ball-in-cone differential pressure shunt valves may increase overdrainage risk. Narrow-lumen high-resistance flow control devices as tested here under similar conditions appear to achieve more consistent flow rates, suggesting their use may be advantageous, and did not demonstrate any blockage or trend of decreasing flow over the 3 wk of chronic use., (Copyright © 2020 by the Congress of Neurological Surgeons.)

Background: Programmable differential pressure (DP) valves combined with an anti-siphon device (ASD) represent the current standard of care in preemtping overdrainage associated with ventriculoperitoneal shunting for hydrocephalus., Objective: We aimed to provide comparative data of four combinations of two ASDs of different working principles in combination with two DP valves in an in vitro model in order to achieve a better understanding of the flow characteristics and potential clinical application., Methods: We analyzed the flow performance of four possible combinations of two DP valves (CHPV [HM]; proGAV 2.0[PG]) in combination with either a gravity-regulated (Shuntassistant [SA]) or a flow-regulated (SiphonGuard [SG]) ASD in an in vitro setup. A DP between 4 and 60 cmH 2 O was generated, and the specific flow characteristics were measured. In addition, the two combinations with gravity-regulated ASDs were measured in defined spatial positions., Results: Flow characteristics of the SA combinations corresponded to the DP in linear fashion and to the spatial position. Flow characteristics of the SG combinations were dependent upon the DP in a non-linear fashion and independent of the spatial position. Highest mean flow rate of the PG-SG- (HM-SG-) combination was 1.41 ± 0.24 ml/min (1.16 ± 0.06 ml/min). The mean flow rates sharply decreased with increasing inflow pressure and subsequently increased slowly up to 0.82 ± 0.26 ml/min (0.77 ± 0.08 ml/min)., Conclusion: All tested device combinations were able to control hydrostatic effect and prevent consecutive excessive flow, to varying degrees. However, significant differences in flow characteristics can be seen, which might be relevant for their clinical application.

Long-term shunt dependency rates in children treated for IIH with CSF diversion have not been established. We therefore present our experience with 4 children shunted for Idiopathic Intracranial Hypertension (IIH) during the years 1988-2000 with very long-time follow-up. Two out of these patients have experienced late or very late episodes of severe shunt failure during the second or third decade after initial shunt treatment. They were all boys and may not be representative for IIH patients as a whole. Two of them appear, however, to be permanently shunt dependent, indicating that long-term shunt dependency in children treated for IIH with CSF diversion may be more common than previously expected.

Objective: Although syringomyelia associated with extensive spinal adhesive arachnoiditis (SAA) can be a progressive disease that has potentially devastating clinical consequences, its surgical resolution has remained poorly defined. The aim of the present study was to verify the safety and efficacy of syringoperitoneal shunting for syringomyelia associated with extensive SAA., Methods: The present retrospective study included 15 patients who had undergone syringoperitoneal shunting with a programmable shunt valve for the diagnosis of syringomyelia associated with extensive SAA from October 2012 to June 2018. The shunt pressure was appropriately adjusted according to the postoperative sequential clinical condition and change in syringomyelia evaluated using magnetic resonance imaging. The average postoperative follow-up duration was 32.7 months., Results: No surgery-related complications such as shunt dysfunction or infection occurred during the follow-up period, except for 2 patients with minor issues with the shunt tube. The average shunt pressure at the last follow-up examination was 4.5 cm H 2 O. The findings from the clinical assessment suggested that the average grade on the sensory pain scale was 2.9 before surgery and had improved significantly to 2.5 at the most recent follow-up examination. Radiological analysis suggested that improvement of syringomyelia was noted in 14 of the 15 patients (93.3%), with no cases of radiological aggravation. No recurrence of syringomyelia developed during the follow-up period in the present study., Conclusion: Syringoperitoneal shunting with a programmable shunt valve was safe and effective for clinical control of syringomyelia associated with extensive SAA. Long-term follow-up is mandatory to monitor for shunt dysfunction and mechanical trouble., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Competing Interests: None

The small molecule fluorescein is commonly used to guide the repair of cerebral spinal fluid leaks (CSFLs) in the clinic. We modified fluorescein so that it is also visible by positron emission tomography (PET). This probe was used to quantitatively track the fast distribution of small molecules in the CSF of rats. We tested this probe in models relevant to the clinical diagnosis and treatment of central nervous system (CNS) diseases that affect CSF flow. In this study, fluorescein was radiolabeled with fluorine-18 to produce Fc-AMBF 3 . [ 18/19 F]-Fc-AMBF 3 was introduced at trace quantities (13.2 nmols, 100 μCi) intrathecally (between L5 and L6) in rats to observe the dynamic distribution and clearance of small molecules in the CSF by both [ 18 F]-PET and fluorescence (FL) imaging. Murine models were used to demonstrate the following utilities of Fc-AMBF 3 : (1) utility in monitoring the spontaneous CSFL repair of a compression fracture of the cribriform plate and (2) utility in quantifying CSF flow velocity during neurosurgical lumboperitoneal shunt placement. Fc-AMBF 3 clearly delineated CSF-containing volumes based on noninvasive PET imaging and in ex vivo FL histology. In vivo morbidity ( n = 16 rats, <2.7 mg/kg, 77 times the PET dose) was not observed. The clearance of the contrast agent from the CNS was rapid and quantitative ( t 1/2 = 33.8 ± 0.6 min by FL and t 1/2 = 26.0 ± 0.5 min by PET). Fc-AMBF 3 was cleared from the CSF through the vasculature and/or lymphatic system that supplies the cribriform plate and the temporal bone. Fc-AMBF 3 can be used to diagnose CSFLs, image CSFL repair, and determine the CSF flow velocity in the CNS or through lumboperitoneal shunts by PET/FL imaging. In conclusion, Fc-AMBF 3 PET imaging has been demonstrated to safely and dynamically quantitate CSF flow, diagnose fistulas associated with the CSF space, and approximate the clearance of small molecules in the CSF.

Background and Purpose: We evaluated the inferior petrosal sinus (IPS) and adjacent cerebellopontine angle (CPA) cistern as a potential implantation site for a novel venous endovascular transdural CSF shunt concept to treat communicating hydrocephalus. We analyzed the dimensions of the IPS, CPA cistern, and distances to adjacent neurovascular structures., Materials and Methods: Gadolinium enhanced T1 weighted brain MRI datasets of 36 randomly selected patients, aged 20-80 years, were analyzed with three-dimensional multiplanar reconstruction to measure IPS diameter and length, CPA cistern depth, and IPS proximity to the vertebrobasilar arteries and brainstem. Statistical analysis was used to assess gender, sidedness, and age dependence., Results: Mean IPS diameter ranged from 2.27 mm to 3.31 mm at three axial levels, with >90% larger than 1.46 mm. CPA cistern adjacent to the IPS exhibited a mean depth of 3.86 mm to 7.39 mm between the dura and brainstem at corresponding axial levels. There was no side dependence except for a longer distance from the IPS to the basilar artery on the left compared with the right (9.72 vs 7.28, P<0.019). Linear regression analysis showed that the distance from the IPS to the brainstem was statistically significantly increased with age (P<0.0002) and was greater in men, with little side variation (P=0.524)., Conclusion: Our results demonstrate sufficient CSF CPA cisternal space adjacent to the IPS and support the feasibility of an endovascular catheter delivered transdural implantable shunt. Such a device could serve to mimic the function of the arachnoid granulation by establishing a regulated path for CSF flow from the intracranial subarachnoid space to the venous system and provide a treatment for communicating hydrocephalus., Competing Interests: Competing interests: AMM and CBH are co-founders and investors of CereVasc, LLC. AMM, CBH, and BMB are shareholders of CereVasc, LLC., (© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Hydrocephalus is a rare complication of brain involving acute lymphoblastic leukemia (ALL). The standard treatment is ventriculoperitoneal (VP) shunting, while ventriculoatrial (VA) shunting is the second option in a case of VP shunt failure in young children. But the presence of port catheter at the right atrium restricts and makes a VA shunt difficult to place in the same atrium. We presented a 4-year-old boy who had the diagnoses of ALL and underwent chemotherapy through a port-a-cath. He also had hydrocephalus due to the brain invasion of the ALL. He firstly underwent VP shunting for the treatment of hydrocephalus, but it failed due to an intraabdominal cyst. Then, he underwent VA shunting through the left internal jugular vein. This is the first case in the literature showing both catheters in the right atrium.

Cerebral spinal fluid (CSF) shunts are the main treatment for hydrocephalus. They divert excess CSF from the ventricular system to the abdominal, pleural, or intravascular space where it is absorbed. The shunt valve regulates flow based on intracranial pressure (ICP) to maintain a physiologically stable and safe ICP. Shunt malfunction is difficult to detect, life-threatening and common. The present study demonstrates that snap-though buckling (STB) shells can be transformed into pressure-relief valves that act in the normal physiological range of ICP. Three different shell designs in this preliminary experiment were found to have opening and closing pressures that fall within the physiologically normal range of ICP of 6 to 25 cm H 2 O. Furthermore, these STB shells demonstrate a valve actuation that is visible by ultrasound and have an implantable form-factor that is similar to currently available shunt valves. The unique characteristics of STB shell valves have potential clinical applications for shunt monitoring using ultrasound imaging and can be fabricated from antibiotic-impregnated materials to mitigate shunt infection. These characteristics make STB valves attractive for future use in cerebral shunt systems., (Copyright © 2019. Published by Elsevier Ltd.)

Background: Spinal catheter insertion in lumboperitoneal (LP) shunt surgery for idiopathic normal pressure hydrocephalus (iNPH) is frequently associated with technical difficulties especially in patients with obesity and elderly patients with vertebral deformities., Objective: To elucidate the accuracy and safety of image-guided spinal catheter placement using a paramedian approach (PMA)., Methods: We retrospectively analyzed 39 consecutive iNPH patients treated by LP shunting with spinal catheter insertion via the PMA. The success rate of catheter placement and the number of changes in puncture location were evaluated. Accuracy of catheter insertion was assessed by measuring both vertical and horizontal deviations in the point of catheter dural penetration from the center of the interlaminar space., Results: The success rate of catheter placement was 100% (39/39). The difficulty rate for catheter insertion, measured by the number of changes in puncture location, was 2.6% (1/39). No bloody punctures or surgical infections were observed. Accuracy of catheter insertion, measured as the degree of deviation, was 0.5 ± 1.9 mm horizontally and 0.0 ± 2.4 mm vertically. The rates of minor complications, including caudal catheter insertion, transient low-pressure headache, and root pain, were 5.1% (2/39), 10.4% (4/39), and 0% (0/43), respectively. Subdural hematoma requiring surgical intervention occurred in 1 case (2.6%). During the mean follow-up period of 36 mo, spinal catheter rupture at the level of the spinous processes was not observed., Conclusion: Fluoroscopic-guided spinal catheter placement via the PMA was safe, accurate, and reliable, even for use in geriatric and obese patients., (© Congress of Neurological Surgeons 2017.)

Introduction:: A dynamic model to evaluate thrombus formation on intravascular catheters in vitro is presented. The model enables fluid infusion, variation in the catheter orientation, and variable flow conditions. It was applied on a catheter used to shunt cerebrospinal fluid to a vein, a dural venous sinus, for the treatment of hydrocephalus., Methods:: Fresh human blood-filled circuits were circulated in a non-occlusive roller pump. A catheter infused either with cerebrospinal fluid, Ringer's lactate, or no fluid (control) was inserted through each circuit's wall. Sixteen circuits (six cerebrospinal fluid, six Ringer's lactate, four control) ran for 60 min. Qualitative assessment was performed by measuring viscoelastic properties of blood at the start and end of the experiment; quantitative evaluation of clot formation by scanning electron microscope., Results:: Average blood velocity was 79 mm/s, with a pressure wave between 5 and 15 mm Hg. At the experiment's end, the infused fluid represented 5.88% of the blood/infusion volume in the circuit. The control circuits showed no statistical difference between the start and end for viscoelastic testing, whereas both Ringer's lactate and cerebrospinal fluid enhanced coagulation, most pronounced for the latter. Most thrombus material was observed on catheters in the cerebrospinal fluid group. Clot formation was less pronounced on the surface of the catheter facing the blood flow., Discussion:: A dynamic model for intravascular catheter testing mimics better clinical conditions when evaluating blood-material interaction. Catheter position, blood flow around the catheter, and infusion fluid all have a potential impact on the hemocompatibility of a given catheter.

Shunt systems are not perfect devices and can cause severe complications. Complications may originate from problems related to the valve, the patient, or the surgery and are more common in neonates, infants, especially preterm, by reason of the special characteristics of these patients. We, therefore, have successfully developed a useful and viable surgical technique in order to provide helpful aspects to the surgical issues mentioned above. This technique includes a "reverse J shaped" skin incision nonintersecting the shunt's hardware and distal catheter to reduce wound problems to a minimum by opening a "bone groove". We believe that the above technique described by us will both reduce issues such as scalp ulceration, wound dehiscence, and shunt exposure in premature and pediatric hydrocephalus cases with a friable scalp, and eliminate a cosmetic problem in hydrocephalic patients of all ages.

Objective: External ventricular drainage (EVD) is an emergent neurosurgical procedure. Many commercial sets are available for EVD that are not always obtainable in all hospitals. The aim of our study was to describe new techniques to perform EVD using simple improvised materials to check the real-world applicability of the same device in the management of acute hydrocephalus and its effectiveness and safety., Methods: We illustrated 2 techniques for a "do it yourself" improvised EVD device using materials available even in non-neurosurgery-dedicated operating rooms. We performed an observational study in our institution (April 2015 to December 2016). We included all patients presenting with acute hydrocephalus and requiring EVD., Results: During a 20-month period, the new EVD device was used as a lifesaving solution for 33 patients. Good outcomes were noted in 11 of the 33 patients (33%). The EVD was complicated by fatal meningitis in 4 of the patients (12%). Malfunction occurred in 6 patients. The new EVD device costs less than US$20 for the first technique and less than US$10 for the second technique. In contrast, the cost of a standard EVD set ranges from US$170 to US$380 in Tunisia., Conclusions: The new EVD device has the potential to improve the quality of efficiency of care in difficult economic times that have changed the medical landscape, because it is both easy to make and cost-effective. Because it is an inexpensive technique, it could also be suitable for low-income countries, where neurosurgery is not yet the first and foremost health priority., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Objective: Proximal obstruction due to cellular material is a major cause of shunt failure in hydrocephalus management. The standard approach to treat such cases involves surgical intervention which unfortunately is accompanied by inherent surgical risks and a likelihood of future malfunction. We report a prototype design of a proximal ventricular catheter capable of noninvasively clearing cellular obstruction. Methods: In-vitro cell-culture methods show that low-intensity ac signals successfully destroy a cellular layer in a localized manner by means of Joule heating induced hyperthermia. A detailed electrochemical model for determining the temperature distribution and ionic current density for an implanted ventricular catheter supports our experimental observations., Results: In-vitro experiments with cells cultured in a plate as well as cells seeded in mock ventricular catheters demonstrated that localized heating between 43 °C and 48 °C caused cell death. This temperature range is consistent with hyperthermia. The electrochemical model verified that Joule heating due to ionic motion is the primary contributor to heat generation., Conclusion: Hyperthermia induced by Joule heating can clear cellular material in a localized manner. This approach is feasible to design a noninvasive self-clearing ventricular catheter system., Significance: A shunt system capable of clearing cellular obstruction could significantly reduce the need for future surgical interventions, lower the cost of disease management, and improve the quality of life for patients suffering from hydrocephalus.

In this research an optimization methodology and 3D computational fluid dynamics algorithm were coupled to reach an important design objective for ventricular catheters: uniform inlet flow distribution. The optimized catheter design presented significantly improves on previous designs explored in the literature and on standard catheter designs used clinically. The automated, iterative fluid simulation framework described in this work can be used to rapidly explore design parameter influence on other flow-related objectives in the future.

Background: Since the 1950s, hydrocephalus has been be treated with cerebrospinal fluid (CSF) shunts, usually to the peritoneal cavity or to the right cardiac atrium. However, because of their siphoning effect, these shunts lead to nonphysiologic CSF drainage, with possible comorbidity and high revision rates. More sophisticated shunt valve systems significantly increase costs and technical complexity and remain unsuccessful in a subgroup of patients. In an attempt to obtain physiologic CSF shunting, many neurosurgical pioneers shunted towards the dural sinuses, taking advantage of the physiologic antisiphoning effect of the internal jugular veins. Despite several promising reports, the ventriculosinus shunts have not yet become standard neurosurgical practice., Methods: In this single-center prospective clinical study, we implanted the retrograde ventriculosinus shunt, as advocated by El-Shafei, in 10 patients. This article reports on our operation technique and long-term outcome, including 4 patients in whom this shunt was implanted as a rescue operation., Results: Implantation of a ventriculosinus shunt proved to be feasible, warranting physiologic drainage of CSF. However, in only 3 of 14 patients, functionality of the retrograde ventriculosinus shunt was maintained during more than 6 years of follow-up. In our opinion, these shunts fail because present venous access devices are difficult to implant correctly and become too easily obstructed. After discussion of possible causes of this frequent obstruction, a new dural venous sinus access device is presented., Conclusion: An easy-to-implant and thrombogenic-resistant dural venous sinus access device needs to be developed before ventriculosinus shunting can become general practice., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The ventriculosinus shunt is a promising treatment for hydrocephalus. Currently, different shunt techniques exist, and it is not clear whether one is preferable. This pilot study reports on a non-hydrocephalic goat model (Saanen breed) that provides opportunities to evaluate and optimize several aspects of the ventriculosinus shunt technique. Analysis of the coagulation properties of 14 goats by a viscoelastic coagulation monitor showed that goats have a hypercoagulable state compared to humans. This property can be partially counteracted by antiplatelet drugs. During implantation of a ventriculosinus shunt, a pulsatile reflux of blood was observed. After implantation, the animals recovered to their preoperative state, and none of them developed a superior sagittal sinus thrombosis. Evaluation of the shunts after 16 days showed an obstructing luminal clot. Several model-related factors may have promoted this obstruction: the absence of hydrocephalus, the hypercoagulability of caprine blood and the smaller dimensions of the caprine superior sagittal sinus. However, the pulsatile reflux of blood, which is caused by the compliance of the shunt system distal to the valve, may have been an important factor as well. In conclusion, the non-hydrocephalic goat model limits animal suffering and simplifies the study protocol. This model allows researchers to evaluate their implantation technique and shunt hardware but not the efficacy of the treatment or shunt survival.

Objectives: Hydrocephalus can be defined as clinically symptomatic dilatation of the internal ventricular system at the expense of brain and blood volume. Shunt insertion is the mainstay of therapy for communicating hydrocephalus. One of the most frequently used valves is the programmable Codman Medos Hakim valve which enables the pressure level to be adjusted from 30 to 200 mmH2O. The problem of functional over- or underdrainage and the associated complications should be significantly reduced if not excluded. Especially in the clinical application of the Codman Medos Hakim Shunt System in hydrocephalus of other etiology only a few studies can be found. This study aims to increase knowledge of both the safety of Codman Medos valves with SiphonGuard in the clinical application as well as the correct choice of the pressure level for different indications., Patients and Methods: In this retrospective study, 101 patients were included who underwent surgery with the adjustable "Codman Medos Hakim" valve with "SiphonGuard" between January 2010 and July 2013. We analyzed the patient files and imaging (CCT, cMRT) data. The statistical examinations were performed using the WINStat program for Excel., Results: Our results show that an initial pressure level of 120mmH2O proved to be suitable in all subgroups. After optimization of the initial pressure level 70.3% of the valves (71 valves) had a pressure level of 120mmH2O. Importantly, only in the SAH subgroup the clinical improvement was correlated with a reduction in the measured indices. But in all subgroups a clinical deterioration was associated with an increased ventricular size., Conclusion: Overall, the clinical data show that an initial pressure level of 120mmH2O seems to be appropriate for most patients treated in this series. Measured indices from the cranial imaging can provide valuable indications for the presence of a suboptimal valve setting for the individual patient., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: Device infection is a major complication of placement external ventricular drains (EVD). Diagnostic features are often masked by underlying disease or cerebrospinal fluid (CSF) contamination by blood. We aim to assess which diagnostic modalities are applied for EVD-related infection (ERI) diagnosis and evaluate their accuracy., Methods: This observational prospective study included 187 adult patients with an EVD. Modalities of clinical diagnosis of ERI diagnosed by treating physicians on clinical grounds and blood and CSF analysis (clinically diagnosed ERI (CD-ERI)) were assessed prospectively. Additionally, the diagnostic accuracy of clinical and laboratory parameters for the diagnosis of culture proven ERI (CP-ERI) was evaluated, using data of the study patients and including a retrospective cohort of 39 patients with CP-ERI., Results: Thirty-one CD-ERIs were diagnosed in the prospective cohort. Most physicians used CSF analysis to establish the diagnosis. ROC analysis revealed an AUC of 0.575 (p = 0.0047) for the number of positive SIRS criteria and AUC of 0.5420 (p = 0.11) for the number of pathological neurological signs for diagnosis of CP-ERI. Diagnostic accuracy of laboratory values was AUC 0.596 (p = 0.0006) for serum white blood cell count (WBCC), AUC 0.550 (p = 0.2489) for serum C-reactive protein, AUC 0.644 (p < 0.0001) for CSF WBCC and AUC 0.690 for CSF WBC/red blood cell count ratio (both p < 0.0001). Neither a temporal trend in potential predictors of CP-ERI nor a correlation between clinical diagnosis and proven CSF infection was found., Conclusions: Clinicians base their diagnosis of ERI mostly on CSF analysis and occurrence of fever, leading to over-diagnosis. The accuracy of the clinical diagnosis is low. Commonly used clinical and laboratory diagnostic criteria have a low sensitivity and specificity for ERI.

The appearance of a subdural hygroma after the rupture of an arachnoid cyst wall is extremely rare, with very few cases described in the literature. Most cases are due to a traumatic cause. The therapeutic approach in symptomatic cases is controversial, with a current tendency toward conservative management initially. In those cases that require surgical treatment, multiple therapeutic options are available, with fenestration techniques being recommended as first-line treatment. We describe 2cases treated in our centre and review the literature., (Copyright © 2018 Sociedad Española de Neurocirugía. Publicado por Elsevier España, S.L.U. All rights reserved.)

Background: Ventriculitis is a serious complication when using external ventricular drains (EVDs). Bactericidal silver coating has been reported to reduce risk of infection. In the clinical setting, the diagnosis is often made based on symptoms and analyses of cerebrospinal fluid, with treatment initiated before infection is verified by culture. The bactericidal effect might not correlate with a reduced rate of clinically diagnosed infections. This retrospective study aimed to analyze if use of silver-coated EVDs is associated with a reduced rate of ventriculitis., Methods: During 1 year, clinical routine was changed from inserting noncoated catheters to silver-coated catheters. Rate of ventriculitis was compared between patient groups based on catheter type. To examine the clinical impact of silver coating, ventriculitis was defined as cases where antibiotic treatment was initiated on clinical suspicion., Results: Among 296 patients (186 noncoated and 110 silver-coated catheters), 18.9% were treated for ventriculitis, with 21.0% in the noncoated group and 15.5% in the silver-coated group (P = 0.242). Silver coating did not reduce the rate of positive cultures. Duration of EVD treatment was the single significant risk factor for ventriculitis. Silver-coated catheters did not reduce the need for cerebrospinal fluid shunt placement, days with antibiotics, days with EVD, or days in the intensive care unit., Conclusions: The previously reported bactericidal effect of silver-coated EVDs did not alter the clinical course to significantly reduce the number of treated cases of ventriculitis. The introduction of silver-coated EVDs cannot be motivated by reduced use of antibiotics or shorter hospital stay., (Copyright © 2018 Elsevier Inc. All rights reserved.)

OBJECTIVE Subdural hematoma (SDH) is the most common serious adverse event in patients with shunts. Adjustable shunts are used with increasing frequency and make it possible to noninvasively treat postoperative SDH. The objective of this study was to describe the prevalence and treatment preferences of SDHs, based on fixed or adjustable shunt valves, in a national cohort of patients with shunted idiopathic normal pressure hydrocephalus (iNPH), as well as to evaluate the effect of SDH and treatment on long-term survival. METHODS Patients with iNPH who received a CSF shunt in Sweden from 2004 to 2015 were included in a prospective quality registry (n = 1846) and followed regarding SDH, its treatment, and mortality. The treatment of SDH was categorized into surgery, opening pressure adjustments, or no treatment. RESULTS During the study period, the proportion of adjustable shunts increased from 75% to 95%. Ten percent (n = 184) of the patients developed an SDH. In 103 patients, treatment was solely opening pressure adjustment. Surgical treatment was used in 66 cases (36%), and 15 (8%) received no treatment. In patients with fixed shunt valves, 90% (n = 17) of SDHs were treated surgically compared with 30% (n = 49) in patients with adjustable shunts (p < 0.001). There was no difference in long-term patient survival between the SDH and non-SDH groups or between different treatments. CONCLUSIONS SDH remains a common complication after shunt surgery, but adjustable shunts reduced the need for surgical interventions. SDH and treatment did not significantly affect survival in this patient group, thus the noninvasive treatment offered by adjustable shunts considerably reduces the level of severity for this common adverse event.

Background: The flow pattern of the cerebrospinal fluid is probably the most important factor related to obstruction of ventricular catheters during the normal treatment of hydrocephalus. To better comprehend the flow pattern, we have carried out a parametric study via numerical models of ventricular catheters. In previous studies, the flow was studied under steady and, recently, in pulsatile boundary conditions by means of computational fluid dynamics (CFD) in three-dimensional catheter models., Objective: This study aimed to bring in prototype models of catheter CFD flow solutions as well to introduce the theory behind parametric development of ventricular catheters., Methods: A preceding study allowed deriving basic principles which lead to designs with improved flow patterns of ventricular catheters. The parameters chosen were the number of drainage segments, the distances between them, the number and diameter of the holes on each segment, as well as their relative angular position., Results: CFD results of previously unreleased models of ventricular catheter flow solutions are presented in this study. Parametric development guided new designs with better flow distribution while lowering the shear stress of the catheters holes. High-resolution 3D printed catheter solutions of three models and basic benchmark testing are introduced as well., Conclusions: The next generation of catheter with homogeneous flow patterns based on parametric designs may represent a step forward for the treatment of hydrocephalus, by possibly broadening their lifespan.

Aim: To evaluate the effect of shunt selection on the rate of shunt revision due to early shunt complications in neonatal myelomeningocele-associated hydrocephalus., Material and Methods: The data of 157 neonatal myelomeningocele cases in three pediatric neurosurgery centers (Ankara University, Kocaeli University, Selcuk University) who underwent shunt surgery at the time of myelomeningocele repair between 2000 and 2014 were retrospectively analyzed. Clinical features of the patients, shunt types, and early shunt complications within the first three months were recorded. The patients were classified according to several features of the shunt systems, such as the valve type, valve size/contour and catheter type., Results: Of all patients, 71 (45.2%) underwent early shunt revision surgery due to various complications. Mechanical complications were the most frequent cause of shunt failure, followed by infection. There was no significant difference among the valve types. Also, no significant difference was observed among the catheter types. Only valve contour/size (contoured regular/ultra-small/burr-hole/ cylindrical/neonatal) seemed to significantly affect the rate of early complications. The patients with neonatal-design valves or ultrasmall valves had significantly less complications, such as poor wound-healing, wound-dehiscence, cerebrospinal fluid leak or shunt exposure. The infection rate secondary to these complications was found to be lower., Conclusion: Myelomeningocele patients with prominent hydrocephalus frequently have a friable skin, due to reduced macrocrania-related subcutaneous tissues. Small-sized (neonatal-design or ultra-small) valves may significantly reduce the early shunt complication rate among this population.

Background: Ventriculoatrial (VA) shunt is a routine technique for the treatment of hydrocephalus. The correct position at the superior vena cava-right atrium junction is generally assessed by radiography. We present the first experience of an alternative, nonradiographic technique to assess the distal end of the VA shunts through an electrocardiographic (EKG) method. The technique has developed from the large experience of central venous catheters (CVC) worldwide; the EKG-guided method is a common and validated alternative to standard radiologic control of the location of the tip of any CVC., Methods: Five consecutive patients underwent VA shunt with venous catheter positioned with the EKG-guided technique. The position of the catheter tip was verified by standard chest radiography., Results: Four men and 1 woman (mean age, 45.4 years) underwent VA shunt for hydrocephalus with the EKG-guided technique. The side of internal jugular vein puncture was the right side in 4 cases and the left side in 1 case. As confirmed by radiography, all VA shunt tips were located within the correct range. There was no radiologic evidence of procedure-related complication or catheters that had to be replaced., Conclusions: The EKG-guided technique for VA shunts is as accurate as fluoroscopy, but simpler, more readily available, less expensive, safer, and more cost effective. It reduces the need of radiography and radiologic exposition for both patients and operators. The EKG method may be a valid and cost-effective alternative to standard radiologic control in VA shunts, as for any central venous access device, and could become the preferential method for confirming tip position during VA shunt surgery., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background/aims: The management of extracerebral collections of fluid in patients with hydrocephalus can be problematic for either their simultaneous separate management or sequential management, each of which may require multiple surgeries and the management of external drains. The object of this report is to review the experience with a shunt configuration that simultaneously diverts ventricular fluid and extracerebral fluid, whether subdural or subarachnoid in location, through different outflow resistances., Methods: The medical records, including neuroimaging of patients with hydrocephalus and clinically significant extracerebral collections of low density who were managed by implanting a differential pressure type shunt, were retrospectively reviewed., Results: Four patients, 3 children and 1 adult, met inclusion criteria. Three had the entire differential pressure shunt implanted under 1 anesthetic, and 1 had a catheter inserted into the subdural space and connected into an existing ventriculoperitoneal shunt system. The extracerebral fluid collections cleared in all 4 patients, and the CSF shunt continued to function normally., Conclusion: A single surgical procedure to implant a differential pressure shunt can simultaneously drain and obliterate an extracerebral fluid collection while managing the hydrocephalus. Compared to routines that include external drainage, differential pressure shunting requires fewer surgeries, shorter hospitalization, with expected less expense., (© 2017 S. Karger AG, Basel.)

Purpose: In this study, we investigate the occurrence rate of early shunt infection and malfunction in pediatric patients after converting an external ventricular drainage (EVD) to a ventriculo-peritoneal shunt (VPS) without replacing the ventricular catheter., Methods: Data was retrospectively reviewed for 17 pediatric patients (11 male (64.7%), mean age 7.5 years, range 0.25-15 years) who underwent 18 consecutive direct conversions of tunneled EVD to VPS without replacing the ventricular catheter between 2008 and 2017. In each case, the EVD was inserted in sterile fashion within the operating room and tunneled subcutaneously 5-7 cm away from the insertion site. Primary outcome measure was the occurrence of early (within 30 days) VPS infection or malfunction. The mean follow-up time was 56.8 months (±35.7 months)., Results: The mean period of EVD before VPS placement was 9.0 days (±3.6 days, range 2-18 days). Five patients had shunt infections/malfunctions. One patient (5.6%) had an early shunt infection after 30 days. One patient had a late shunt infection after 9 months. One patient had an early shunt malfunction after 9 days. Two patients (11.1%) had late shunt malfunctions after 6.5 months and 9 years. There were no other incidents of shunt-related complications or shunt-related mortality., Conclusion: In the pediatric population, the conversion of a tunneled EVD to a VPS without replacing the ventricular catheter can be safely done. Cranial entry is spared, while the rates of shunt infection and malfunction do not increase significantly.

Background: Intraventricular hemorrhage requiring ventriculostomy placement is a frequent complication of spontaneous intracerebral hemorrhage. Although a subset of patients will require permanent ventricular shunt placement, little is known about contemporary practices regarding the timing of ventriculostomy and ventricular shunt placement after intracerebral hemorrhage., Methods: Using the 2010-2012 National Inpatient Sample, we identified patients with International Classification of Diseases, Ninth Revision codes for intracerebral hemorrhage, excluded secondary causes, and examined procedure dates., Results: Of 35,899 patients with primary intracerebral hemorrhage, 2443 (6.8%) received ventriculostomy, 93% within the first 3 days of admission and 66% within the first day. Permanent shunt placement occurred in 173 (7.1%) patients following ventriculostomy at a median interval of 15 days (interquartile range: 11-20). Among those remaining alive and in hospital at 14, 21, and 28 days, 5%, 11%, and 15%, respectively, underwent shunt placement following ventriculostomy, and 24% of those with multiple ventriculostomy insertions required permanent shunt by 4 weeks of hospitalization. Multiple ventriculostomies, tracheostomy, and black race were associated with longer time to permanent shunt., Conclusions: A wide variation in delay to permanent shunt placement is present, with substantial and increasing prevalence with time in hospital. Better understanding of the risk factors associated with persistent hydrocephalus will help optimize patient selection and timing of treatment., (Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.)

Cerebrospinal fluid diversion has become the mainstay treatment in hydrocephalus for over 50 years. As the number of patients with ventricular shunt systems increases, neurointensivists are becoming the first-line physicians for many of these patients. When symptoms of a shunt malfunction are suspected and access to a neurosurgeon is limited or delayed, workup and temporizing measures must be initiated. The article highlights the functional nuances, complications, and management of current programmable shunt valves and their MRI sensitivity.

Objectives: Shunt implantation is an option in the treatment of hydrocephalus. However, the benefits and adverse effects of programmable shunt valves have not been well assessed., Materials and Methods: Randomized controlled trials (RCTs) and observational studies assessing the efficacy and safety of programmable valves (PV) treatment for hydrocephalus were identified from electronic databases (PubMed, EMBASE, and Cochrane library). The meta-analysis was performed with the fixed-effect model or random-effect model according to heterogeneity., Results: Three RCTs and eight observational studies met the inclusion criteria including 2622 subjects. Compared with non-PV, PV treatment did not have a statistically significant effect on one-year shunt survival rate [relative risk (RR), 1.06; 95% confidence interval (CI), 0.84-1.35], Substantial heterogeneity was observed between studies (P = 0.09; I 2  = 65%). PV administration significantly reduced revision rate (RR, 0.56; 95% CI, 0.45-0.69; I 2  = 29%; P = 0.23) and over- or under-drainage complications rate (RR, 0.55; 95% CI, 0.32-0.96). PV was not associated with increased rates of other adverse events, including overall complications rate, infection rate and catheter-related complications rate., Conclusions: PV treatment is safe and may reduce the revision rate and over- or under-drainage complication rate, especially in patients aged less than 18 years with hydrocephalus. PV treatment is not associated with decreased overall complication rates in patients with hydrocephalus, but the trial sequential analysis indicate more studies are needed to confirm this result., (Copyright © 2017. Published by Elsevier Ltd.)

Background: Three different types of anti-siphon devices (ASDs) have been developed to counteract siphoning-induced overdrainage in upright posture. However, it is not known how the different ASDs affect CSF dynamics under the complex pressure environment seen in clinic due to postural changes. We investigated which ASDs can avoid overdrainage in upright posture best without leading to CSF accumulation., Methods: Three shunts each of the types Codman Hakim with SiphonGuard (flow-regulated), Miethke miniNAV with proSA (gravitational), and Medtronic Delta (membrane controlled) were tested. The shunts were compared on a novel in vitro setup that actively emulates the physiology of a shunted patient. This testing method allows determining the CSF drainage rates, resulting CSF volume, and intracranial pressure in the supine, sitting, and standing posture., Results: The flow-regulated ASDs avoided increased drainage by closing their primary flow path when drainage exceeded 1.39 ± 0.42 mL/min. However, with intraperitoneal pressure increased in standing posture, we observed reopening of the ASD in 3 out of 18 experiment repetitions. The adjustable gravitational ASDs allow independent opening pressures in horizontal and vertical orientation, but they did not provide constant drainage in upright posture (0.37 ± 0.03 mL/min and 0.26 ± 0.03 mL/min in sitting and standing posture, respectively). Consequently, adaptation to the individual patient is critical. The membrane-controlled ASDs stopped drainage in upright posture. This eliminates the risk of overdrainage, but leads to CSF accumulation up to the volume observed without shunting when the patient is upright., Conclusions: While all tested ASDs reduced overdrainage, their actual performance will depend on a patient's specific needs because of the large variation in the way the ASDs influence CSF dynamics: while the flow-regulated shunts provide continuous drainage in upright posture, the gravitational ASDs allow and require additional adaptation, and the membrane-controlled ASDs show robust siphon prevention by a total stop of drainage.

Background: In hydrocephalus shunt surgery, a peritoneal catheter is traditionally inserted with laparotomy incision. The abdominal incision length will not be shorter than 3 cm in most cases. A longer incision has to be made in obese patients. The lateral position in lumboperitoneal shunt (LPS) surgery also increases the difficulty of laparotomy. This report introduces a simple technique of pneumoperitoneal puncture for peritoneal catheter placement in LPS surgery., Methods: Twenty-eight communicating hydrocephalus cases underwent pneumoperitoneal puncture in an LPS operation. Abdominal incision length, time for peritoneal catheter placement, and postoperative complications were recorded., Results: The length of the abdominal incision was 1 cm, and the average time for peritoneal catheter placement was 3.5 minutes. No patient suffered from infection and obstruction. Two cases of subdural hematoma because of cerebrospinal fluid overdrainage occurred., Conclusions: The pneumoperitoneal puncture technique has proven, in our experience, to be a minimally invasive, simple, and reliable method in a peritoneal catheter placement procedure. This technique, which needs to be assessed further by larger case series, may be considered a new method of choice for peritoneal catheter placement in LPS surgery., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Objective: This study aimed to determine whether smartphones affect programmable shunts., Methods: iPhone 5S (Apple Inc., Cupertino, CA, USA) and Samsung Galaxy S5 (Samsung Electronics, Gumi, South Korea) smartphones were chosen for this study. For both phones, magnetic field mapping was performed with 3-dimensional magnetic scanning systems constructed with high-precision motorized stages, and a Hall effect sensor was used to measure the flux density on the smartphone surface. The distance (h) between the distal outlet of the reservoir and the rugby ball of the Strata valve (Medtronic Inc., Minneapolis, MN, USA) was measured using highly sensitive microanalysis optical method. During optical microanalysis, while keeping a 3-cm distance between the valve and the magnetic generator, the h value (μm) was recorded for different magnetic flux densities (MFDs). Then, direct x-ray radiography was performed for radiologic assessment after each process under different magnetic fields. For analysis of the Codman Certas valve (Codman Neuro, Raynham, MA, USA), the magnet orientation and the angle between the magnet with the tantalum ball were measured with the same optical analysis., Results: Maximum MFDs found 62 G for iPhone 5S and 61 G for Samsung Galaxy S5. When the magnetic generator formed a current at 0, 30, 60, and 90 G, the h values of the Strata valve adjusted to 100 mm H 2 O opening pressure were 320, 280, 190, and 175 μm, respectively. When the magnetic generator was removed from the environment, the h value returned to 320 μm. In direct graphs taken after each optical analysis at different Gauss values, substitution was not observed at the indicator. The angle in the Codman Certas valve was 123.9°, 112.5°, and 103.6° at the magnetic flux densities of 0, 60, and 90 G, respectively. When the magnetic field was removed (0 G), the angle was still 103.6°, suggesting an irreversible effect in the shunt construct., Conclusions: Smartphones exert reversible effects on Strata programmable valves without producing remarkable radiologic findings and irreversible effects on Codman Certas valves., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Cerebrospinal fluid (CSF) shunts are life-long implants, and patients have reported anecdotally on noises associated with their shunts. There is, however, a marked lack of information regarding acoustic phenomena related to CSF shunts., Methods: We identified all patients who had been treated or followed in our neurosurgical department within a 15-year period from January 2000 up to the end of 2014. After approval of the local ethics committee all patients who were cognitively intact were explored by a questionnaire and by personal interview about acoustic phenomena related to their shunts., Results: Three hundred forty-seven patients were eligible for the survey, and 260 patients completed the questionnaire. Twenty-nine patients (11.2%) reported on noises raised by their shunts. All of them experienced short-lasting noises while changing body posture, mainly from a horizontal to an upright position, or while reclining the head. Most of the patients reported on soft sounds, but loud and even very loud noises occurred in some patients. Seventy-six percent of the patients were not bothered by these noises as they considered it as a normal part of the therapy or as proof that the shunt device was functioning. Modern valves with gravitational units are prone to produce noises in young adults, but nearly all valve types can evoke noises., Conclusions: Noises caused by a shunt do occur in a considerable number of patients with shunts. One should be aware of this phenomenon, and these patients must be taken seriously.

Background: Syringomyelia is a progressive cerebrospinal fluid disorder that can lead to irreversible spinal cord injury. To date, the optimal management of syringomyelic cavities remains controversial. Multiple studies have emphasized the importance of the craniocervical decompression or shunting procedures; however, except for syrinx related to Chiari malformation, nearly one-half of patients need to undergo reoperation. The purpose of the present study was to describe a simple and efficient surgical technique and to report the long-term radioclinical outcomes., Material and Methods: We report a series of 17 consecutive patients (10 male, 7 female) with symptomatic syringomyelia treated by myringotomy tube between January 1999 and January 2014. The mean follow-up was 43.6 months (5-118). For each case, a laminectomy was carried out at the level of the most expanded part of the syrinx. The myringotomy tube was then placed through a puncture myelotomy., Results: Clinical examination showed disappearance of symptoms in 3 cases, a significant improvement in 8 cases, stabilization in 5 patients, and continuation of neurologic deterioration in 1 case. Thus, favorable long-term outcomes were observed in two-thirds of patients. No permanent postoperative complication was reported. The postoperative imaging showed complete or almost complete disappearance of the syrinx in 11 cases and a reduction over 80% in 4 cases. In 2 cases, the cavity remained stable. Moreover, just 2 patients had to undergo reoperation with the placement of a syringoperitoneal shunt., Conclusion: A myringotomy tube is a simple surgical technique that seems to be an efficient and safe treatment for syringomyelic cavities., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Aim: To investigate whether programmable cerebrospinal fluid (CSF) shunts are influenced by exposure to the magnetic field and to compare the effects of magnetic field in 4 different brands of programmable CSF shunts., Material and Methods: This experimental study was performed in the laboratory using a novel design of magnetic field. Four types of programmable CSF shunts (Miethke®, Medtronic®, Sophysa® and Codman®Hakim®) were exposed to the magnetic field generated by an apparatus consisting of Helmholtz coil for 5 minutes. In every CSF shunt, initial pressures were adjusted to 110 mm H2O and pressures after exposure to magnetic field were noted. These measurements were implemented at frequencies of 5 Hz, 20 Hz, 30 Hz, 40 Hz, 60 Hz and 80 Hz. In each type, three shunts were utilized and evaluations were made twice for every shunt., Results: At 5, 30, 40 and 60 Hz, Groups 1, 2 and 3 had significantly higher average pressures than Group 4. At 20 and 80 Hz, Groups 1 and 2 had notably different pressure values than Groups 3 and 4. Group 3 displayed the highest pressure, while Group 4 demonstrated the lowest pressure., Conclusion: Exposure to magnetic fields may affect the pressures of programmable CSF shunts. However, further controlled, clinical trials are warranted to elucidate the in-vivo effects of magnetic field exposure.

Although cerebrospinal fluid (CSF) shunt placement is the most common procedure performed by pediatric neurosurgeons, shunts remain among the most failure-prone life-sustaining medical devices implanted in modern medical practice. This article provides an overview of the mechanisms of CSF shunt failure for the 3 most commonly employed definitive CSF shunts in the practice of pediatric neurosurgery: ventriculoperitoneal, ventriculopleural, and ventriculoatrial. The text has been partitioned into the broad modes of shunt failure: obstruction, infection, mechanical shunt failure, overdrainage, and distal catheter site-specific failures. Clinical management strategies for the various modes of shunt failure are discussed as are research efforts directed towards reducing shunt complication rates. As it is unlikely that CSF shunting will become an obsolete procedure in the foreseeable future, it is incumbent on the pediatric neurosurgery community to maintain focused efforts to improve our understanding of and management strategies for shunt failure and shunt-related morbidity., (© 2017 S. Karger AG, Basel.)

Cerebrospinal fluid diversion via ventricular shunting is the prevailing contemporary treatment for hydrocephalus. The CSF shunt appeared in its current form in the 1950s, and modern CSF shunts are the result of 6 decades of significant progress in neurosurgery and biomedical engineering. However, despite revolutionary advances in material science, computational design optimization, manufacturing, and sensors, the ventricular catheter (VC) component of CSF shunts today remains largely unchanged in its functionality and capabilities from its original design, even though VC obstruction remains a primary cause of shunt failure. The objective of this paper is to investigate the history of VCs, including successful and failed alterations in mechanical design and material composition, to better understand the challenges that hinder development of a more effective design.

Background: Anti-siphon devices and gravitational-assisted valves have been introduced to counteract the effects of overdrainage after implantation of a shunt system. The study examined the flow performance of two gravitational-assisted valves (shunt assistant - SA and programmable shunt assistant - proSA, Miethke & Co. KG, Potsdam, Germany) in an in vitro shunt laboratory with and without motion., Methods: An in vitro laboratory setup was used to model the cerebrospinal fluid (CSF) drainage conditions similar to a ventriculo-peritoneal shunt and to test the SA (resistance of +20 cmH2O in 90°) and proSA (adjustable resistance of 0 to +40 cmH2O in 90°). The differential pressure (DP) through the simulated shunt and tested valve was adjusted between 0 and 60 cmH2O by combinations of different inflow pressures (40, 30, 20, 10, and 0 cmH2O) and the hydrostatic negative outflow pressure (0, -20, and -40 cmH2O) in several differing device positions (0°, 30°, 60°, and 90°). In addition, the two devices were tested under vertical motion with movement frequencies of 2, 3, and 4 Hz., Results: Both gravity-assisted units effectively counteract the hydrostatic effect in relation to the chosen differential pressure. The setting the proSA resulted in flow reductions in the 90° position according to the chosen resistance of the device. Angulation-related flow changes were similar in the two devices in 30-90° position, however, in the 0-30° position, a higher flow is seen in the proSA. Repeated vertical movement significantly increased flow through both devices. While with the proSA a 2-Hz motion was not able to induce additional flow (0.006 ± 0.05 ml/min), 3- and 4-Hz motion significantly induced higher flow values (3 Hz: +0.56 ± 0.12 ml/min, 4 Hz: +0.54 ± 0.04 ml/min). The flow through the SA was not induced by vertical movements at a low DP of 10 cmH2O at all frequencies, but at DPs of 30 cmH2O and higher, all frequencies significantly induced higher flow values (2 Hz: +0.36 ± 0.14 ml/min, 3 Hz: +0.32 ± 0.08 ml/min, 4 Hz: +0.28 ± 0.09 ml/min)., Conclusions: In a static setup, both tested valves effectively counteracted the hydrostatic effect according to their adjusted or predefined resistance in vertical position. Motion-induced increased flow was demonstrated for both devices with different patterns of flow depending on applied DP and setting of the respective valve. The documented increased drainage should be considered when selecting appropriate valves and settings in very active patients.