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It has been hypothesized that physiological shear forces acting on medical devices implanted in the brain significantly accelerate the rate to device failure in patients with chronically indwelling neuroprosthetics. In hydrocephalus shunt devices, shear forces arise from cerebrospinal fluid flow. The shunt’s unacceptably high failure rate is mostly due to obstruction with adherent inflammatory cells. Astrocytes are the dominant cell type bound directly to obstructing shunts, rapidly manipulating their activation via shear stress-dependent cytokine secretion. Here we developed a total internal reflection fluorescence microscopy combined with a microfluidic shear device chip (MSDC) for quantitative analysis and direct spatial-temporal mapping of secreted cytokines at the single-cell level under physiological shear stress to identify the root cause for shunt failure. Real-time secretion imaging at 1-min time intervals enabled successful detection of a significant increase of astrocyte IL-6 cytokine secretion under shear stress greater than 0.5 dyne/cm2, validating our hypothesis and highlighting the importance of reducing shear stress activation of cells., Khodadadei et al. investigate the mechanisms underlying cerebral shunt failure using a microfluidic chip to simulate shear forces in the shunt. Employing total internal reflection fluorescence imaging, their findings indicate that astrocyte interleukin-6 cytokine secretions increase under higher shunt shear stresses, informing future shunt design and potential drug therapies to reduce shunt failure in patients.

OBJECTIVEPatients with shunted hydrocephalus often accumulate high levels of radiation over their lifetimes during evaluation of hardware integrity. Current practice involves the use of a series of conventional radiographs for this purpose. Newer low-dose EOS radiography is currently used to evaluate scoliosis but has not been explored to evaluate shunt integrity on a large scale. The goal of this study was to compare the quality of imaging using EOS low-dose radiography to conventional radiography to evaluate shunt tubing.METHODSA retrospective chart review was performed on 57 patients who previously had both conventional radiographs and low-dose EOS images of their cerebral shunt tubing from 2000 to 2018. Patient demographics (age, sex, type of shunt tubing, primary diagnosis) were collected. Conventional radiographic images and low-dose EOS images were independently analyzed by a neurosurgeon and neuroradiologist in three categories: image quality, delineation of shunt, and distinction of shunt compared to adjacent anatomy.RESULTSAll patients had shunted hydrocephalus due to spina bifida and Chiari type II malformation. Ratings of EOS and conventional radiographic images by both raters did not differ significantly in terms of image quality (rater 1, p = 0.499; rater 2, p = 0.578) or delineation of shunt (p = 0.107 and p = 0.256). Conventional radiographic images received significantly higher ratings than EOS on the ability to distinguish the shunt versus adjacent anatomy by rater 1 (p = 0.039), but not by rater 2 (p = 0.149). The overall score of the three categories combined was not significantly different between EOS and conventional radiography (rater 1, p = 0.818; rater 2, p = 0.186). In terms of cost, an EOS image was less costly than a conventional radiography shunt series ($236–$366 and $1300–$1547, respectively). The radiation dose was also lower for EOS images, with an effective dose of 0.086–0.140 mSv compared to approximately 1.6 mSv for a similar field of view with conventional radiography.CONCLUSIONSThe image quality of low-dose EOS radiography does not significantly differ from conventional radiography for the evaluation of cerebral shunts. In addition, EOS affords a much lower radiation dose and a lower cost.

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 H2O. 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.

We present a dissection of the patent ductus arteriosus and pulmonary artery for surgical repair utilising cardiopulmonary bypass in the setting of vein of Galen malformation. Several strategies were employed to attenuate the cerebral shunt including pH-stat, high cardiac index, restrictive venous drainage, continuous ventilation and deep hypothermic circulatory arrest. The patient recovered from surgery with no apparent neurological sequelae.

Carcinomas showing thymic-like differentiation (CASTLE tumors) are very rare entities requiring an individualized therapeutic plan. This report describes a case of reconstruction of the innominate artery after radical resection of the tumor in a patient in whom a custom-made cerebral shunt was used for continuous cerebral perfusion.

Objectives Measurement of intracranial pressure (ICP) plays an important role in long-term monitoring and neuro-intensive treatment of patients with a cerebral shunt. Currently, only two complete telemetric implants with different technical features are available worldwide. This prospective pilot study aims to examine patients who had both probes implanted at overlapping times for clinical reasons and represents the first in vivo comparison of both measurement methods. Materials and methods Patients with a primary subarachnoid hemorrhage or a spontaneous intracerebral hemorrhage with ventricular hemorrhage who had received a telemetric ICP probe (Raumedic® NEUROVENT®-P-tel) were included in the study. Conventional external ventricular drainages (EVD) and ventriculoperitoneal shunts with a telemetric ICP probe (Miethke Sensor Reservoir) were implanted in patients with hydrocephalus who required CSF (cerebrospinal fluid) drainage. Absolute ICP values from all systems were obtained. Due to the overlapping implantation time, parallel ICP measurements were performed via two devices simultaneously. ICP measurements via the sensor reservoir were repeated after 3 and 9 months. Differences between the absolute ICP values measured via the NEUROVENT®-P-tel probe, the Miethke sensor reservoir®, and the EVD were analyzed. Results Seventeen patients were included in the present study between 2016 and 2018. 63% of all patients were male. In 11 patients the ICP measurements were followed up with both devices for 3 months. ICP measurements of the sensor reservoir showed corresponding trends in 9 cases compared to ICP measurement via the telemetry probe or EVD. Difference in absolute ICP values ranged between 14.5 mmHg and 0.0 mmHg. The average difference of the absolute ICP values in 8 cases was ≤ 3.5 mmHg. Conclusion ICP measurements with both systems continuously showed synchronous absolute ICP values, however absolute values of ICP measurement with the different systems did not match.

Recently published case reports relating to anesthesia in patients with coronavirus disease (COVID-19) were reviewed. The diagnosis of COVID-19 was confirmed by positive results of reverse transcriptase polymerase chain reaction test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Numerous reports handled emergency cesarean delivery. Primary symptoms and laboratory data of pregnant women with COVID-19 were similar to those of non-pregnant patients. Although the mortality rate is reported to be high after surgery in patients with COVID-19, cesarean delivery was successfully performed under regional anesthesia in most cases and postoperative course was favorable both in the parents and newborns. There is no direct evidence of vertical mother-to-child transmission of SARS-CoV-2; however, a diagnosis of COVID-19 was made in a newborn two hours after delivery from a pregnant woman with COVID-19, based on the increased immunoglobulin levels and deranged liver function, suggesting that its possibility cannot be completely eliminated. Emergency cerebral shunt reconstruction was performed repeatedly in an eight-month-old boy with COVID-19. The tracheal tube was removed in the operating room after surgery and postoperative course was uneventful. All the procedures should be performed in isolated operating rooms with medical staff with level-3 personal protection to ensure the safety of patients and health care providers.

Purpose Correct placement of the ventricle catheter directly influences the function of cerebral shunt systems. The incidence of proximal catheter misplacement reaches up to 45%. To avoid misplacements and revisions a new intra-catheter endoscope for precise ventricle catheter placement in children was evaluated. Methods The semi-rigid ShuntScope (Karl Storz GmbH & Co.KG, Tuttlingen, Germany) with an outer diameter of 1.0 mm and an image resolution of 10,000 pixels was used in a series of 27 children and adolescents (18 males, 9 females, age range 2 months–18 years). Indications included catheter placement in aqueductal stenting (n = 4), first time shunt placement (n = 5), burr hole reservoir insertion (n = 4), catheter placement after endoscopic procedures (n = 7) and revision surgery of the ventricle catheter (n = 7). Results ShuntScope guided precise catheter placement was achieved in 26 of 27 patients. In one case of aqueductal stenting, the procedure had to be abandoned. One single wound healing problem was noted as a complications. Intraventricular image quality was always sufficient to recognize the anatomical structures. In case of catheter removal, it was helpful to identify adherent vessels or membranes. Penetration of small adhesions or thin membranes was feasible. Postoperative imaging studies demonstrated catheter tip placements analogous to the intraoperative findings. Conclusions Misplacements of shunt catheters are completely avoidable with the presented intra-catheter technique including slit ventricles or even aqueductal stenting. Potential complications can be avoided during revision surgery. The implementation of the ShuntScope is recommended in pediatric neurosurgery.

Surgical repair of cardiac defects using cardiopulmonary bypass (CPB) in patients with vein of Galen malformation (VGM), presents a serious challenge to the extent that it has been reported only once before. Multiple case reports describe poor outcome, or the use of hybrid procedures avoiding CPB and recommend conservative management until the VGM has been eradicated. Of particular concern is the high blood flow shunting through the VGM which may be so significant that it might reduce cerebral and somatic perfusion to the extent that hypoxic ischaemic injury is induced. Using a combination of high cardiac index and pH-stat blood gas management maximises cerebral protection whilst cooling the patient to 18°C allows Deep Hypothermic Circulatory Arrest (DHCA) facilitated repair of the cardiac lesion to be undertaken safely. By applying resistance to the venous drainage, a positive central venous pressure (CVP) can be maintained avoiding decompression of the central veins which would otherwise exacerbate the cerebral shunt flow. Using a case study of a 23 day old female neonate with dissection of the patent ductus arteriosus (PDA) and pulmonary artery in combination with VGM, we present the key criteria for successful management and the physiological mechanisms.

Purpose: Current treatment of intraventricular hemorrhage (IVH) involves cerebral shunt placement or an invasive brain surgery. Magnetic resonance-guided focused ultrasound (MRgFUS) applied to the brains of pediatric patients presents an opportunity to treat IVH in a noninvasive manner, termed “incision-less surgery.” Current clinical and research focused ultrasound systems lack the capability to perform neonatal transcranial surgeries due to either range of motion or dexterity requirements. A novel robotic system is proposed to position a focused ultrasound transducer accurately above the head of a neonatal patient inside an MRI machine to deliver the therapy. Methods: A clinical Philips Sonalleve MRgFUS system was expanded to perform transcranial treatment. A five degree-of-freedom MR-conditional robot was designed and manufactured using MR compatible materials. The robot electronics and control were integrated into existing Philips electronics and software interfaces. The user commands the position of the robot with a graphical user interface, and is presented with real-time MR imaging of the patient throughout the surgery. The robot is validated through a series of experiments that characterize accuracy, signal-to-noise ratio degeneration of an MR image as a result of the robot, MR imaging artifacts generated by the robot, and the robot's ability to operate in a representative surgical environment inside an MR machine. Results: Experimental results show the robot responds reliably within an MR environment, has achieved 0.59 ± 0.25 mm accuracy, does not produce severe MR-imaging artifacts, has a workspace providing sufficient coverage of a neonatal brain, and can manipulate a 5 kg payload. A full system demonstration shows these characteristics apply in an application environment. Conclusions: This paper presents a comprehensive look at the process of designing and validating a new robot from concept to implementation for use in an MR environment. An MR conditional robot has been designed and manufactured to design specifications. The system has demonstrated its feasibility as a platform for MRgFUS interventions for neonatal patients. The success of the system in experimental trials suggests that it is ready to be used for validation of the transcranial intervention in animal studies.

Pediatric patients with multiloculated hydrocephalus represent a neurosurgical challenge. While multiloculated hydrocephalus is a relatively rare occurrence, patients with this pathology may require multiple surgeries and complicated shunt designs. Additionally, their neurological outcome tends to be poorer than hydrocephalic patients without loculations. This chapter describes risk factors for multiloculated hydrocephalus such as neonatal infection and intraventricular hemorrhage. Diagnostic criteria and methods for imaging multiloculated hydrocephalus are also discussed. Several common treatments are discussed including shunting, craniotomy for fenestration of loculations, and neuroendoscopic fenestration of loculations. Finally, possible methods for the prevention of multiloculated hydrocephalus are discussed.

OBJECT Cerebral shunt malfunction is common but often difficult to effectively diagnose. Current methods are invasive, involve ionizing radiation, and can be costly. The authors of this study investigated the feasibility of quantitatively measuring CSF flow in a shunt catheter using contrast-enhanced ultrasound. METHODS A syringe pump was used to push a solution of gas-filled microbubbles at specific flow rates through a shunt catheter while a high-frequency ultrasound imaging system was used to collect ultrasound images for offline processing. Displacement maps and velocity profiles were generated using a speckle-tracking method based on a cross-correlation algorithm. An additional correction factor, to account for a predictable underestimation and to adjust the measured flow rates, was calculated based on the geometry of the ultrasound imaging plane and assuming a simple model of laminar flow. RESULTS The developed method was able to differentiate between physiologically relevant flow rates, including no flow and 0.006 to 0.09 ml/min, with reasonable certainty. The quantitative measurement of flow rates through the catheter using this method was determined to be in good agreement with the expected flow rate. CONCLUSIONS This study demonstrated that contrast-enhanced ultrasound has the potential to be used as a minimally invasive and cost-effective alternative method for outpatient shunt malfunction diagnosis.

We present two cases of cerebral shunts - a ventriculopleural shunt and a ventriculoperitoneal shunt, with their associated complications. We also hope to provide a comprehensive literature review on various imaging modalities, including nuclear medicine studies in evaluating cerebral shunt complications.

Enlarged vestibular aqueduct syndrome (EVAS) is the most common congenital ear anomaly that causes sensorineural hearing loss in children and may predispose a child to sudden hearing loss from sudden pressure changes or minor head trauma. We report a case of a 4-year-old boy with a history of a ventriculoperitoneal shunt and migraines who presented to the emergency department with parental and child care provider reports of acute hearing loss, without a history of trauma, infection, or hardware malfunction, who was diagnosed with bilateral EVAS. Diagnosis of EVAS occurs with specific temporal bone imaging with either high-resolution, thin-cut computed tomography or magnetic resonance imaging scans. Enlarged vestibular aqueduct syndrome is typically refractory to medical treatment and often results in hearing loss that is too severe to benefit from amplification, requiring cochlear implantation.

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. 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. 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. 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.

Among childhood cancer survivors (CCSs), non-melanoma skin cancer (NMSC) is the most common type of second malignancy. Morbidity related to the development of NMSC in this group of patients may be sometimes unpredictable and difficult to manage. We present the case of a 49-year-old female who was a CCS and developed giant superficial basal cell carcinomas (sBCCs) over the previously irradiated field of the scalp. BCC involved the atrophic skin overlying the catheter of the peritoneal cerebral shunt that was set there for the management of hydrocephalus. Topical treatment with imiquimod 5% resulted in local skin reaction that was further complicated with catheter exposure. The patient underwent an emergency neurosurgery for reposition of the cerebral shunt. Subsequent treatment with imiquimod resulted in complete resolution of sBCC. Given the increased risk for the development of BCCs in CCSs, awareness of neurosurgeons is crucial. Avoidance of setting the catheter of the cerebral shunt within the radiotherapy field is highly recommended, in order to avoid unnecessary future surgeries and subsequent morbidity, as in our case.

Background: Endoscopic third ventriculostomy (ETV) is the process of intra cranial CSF diversion to relieve the pressure inside the ventricles. This allows the cerebrospinal fluid to flow directly to the basal cisterns, thereby shortcutting any obstruction. It is used as an alternative to a cerebral shunt surgery. Objectives: To observe the Endoscopic third ventriculostomy (ETV) with causal factors and outcome. Methodology: The study was conducted in the Department of Neurosurgery in National Institute of Neurosciences (NINS) during the period from June, 2013 to August, 2014. All the study subjects included in the study were selected for endoscopic third ventriculostomy (ETV) following clinical and radiological diagnosis of hydrocephalus or raised ICP irrespective of age, sex and causal factors. The patients were followed post operatively to follow the outcome. Result: ETV was performed among 38 males and 35 females with a mean age of 24.67 years. Three major causal factors for ETV were aqueductal stenosis, posterior fossa SOL and CP angle tumour observed in 25 (34.3%), 22(30.2%), 11(15.1%) cases respectively. The successful ETV was done in 49 (67.1%) patients varied widely by diagnosis and patient age. Other 32.9% had suffered from several complications like local CSF drainage, local infection, meningitis and subarachnoid haemorrhage and treated conservatively. Conclusion: Endoscopic third ventriculostomy (ETV) is a safe and successful procedure in the management obstructive hydrocephalus. J. Natl Inst. Neurosci Bangladesh 2015;1(1):5-7

Introduction: Infections are still the most common complications of cerebral shunt procedures. Even though fungal etiologies are considered to be rare, they are associated with significant morbidity and mortality. Due to their uncommonness, diagnostic procedures and optimal therapy are poorly defined. We report a case of Candida tropicalis infection of ventriculo-peritoneal cerebrospinal fluid (CSF) shunt in a 49-year-old immune competent male treated with voriconazole (VOR). Methods: Microbiological and CSF markers (1,3-b-D-glucan-BDG) of fungal infection, biofilm production capacity, sensitivity of serial isolates of the pathogen, and the concentration of the antifungal drug have been monitored and related to the clinical course of this infection. Results: Despite appropriate treatment with VOR, in terms of adequate achieved CSF drug concentrations and initial effective therapeutic response, loss of VOR susceptibility of the C tropicalis and treatment failure were observed. Conclusion: Biofilm production of the C. tropicalis isolate might have had a significant role in treatment failure. Of interest, clinical and microbiological unfavorable outcome was anticipated by persistence of BDG in CSF. Rising titers of this marker were associated with relapse of fungal infection.

Purpose The purpose of this study is to describe an intravessel cerebral shunt that allows perfusion of both cerebral hemispheres through the axillary artery. Description The cerebral shunt is a 10-cm to 12-cm long cannula with a lumen for blood perfusion and two balloons, one at each distal end. The proximal ballon is adapted for retaining the proximal end of the catheter in the innominate artery; the second inflatable balloon is adapted for retaining the distal end of the catheter into the left common carotid artery. Evaluation Three consecutive patients received bilateral brain perfusion through the right axillary artery with the use of this cerebral shunt. Conclusions The cerebral shunt allowed bilateral cerebral perfusion as verified with cerebral oxymetry in the absence of any evident neurologic dysfunction.

Introduction Over 25% of the more than 725,000 cases of nosocomial infection in the United States are related to an implantable device. Despite the standard typical strategies available, infection rates for breast implants, cerebrospinal shunts, and penile implants remain unacceptably high. This paper will review use of a “no-touch” technique in varied surgical procedures from orthopedic fracture repair, cerebrospinal fluid shunt placement, and breast reconstruction/augmentation to penile prosthesis implantation. Aim One of our aims was to investigate whether the “no-touch” concept was unique to the field of penile implants and if similar results were obtained in other subspecialties. The other was to examine whether the low infection rate initially obtained with the “no-touch” technique was maintained for a larger number of penile implant procedures. Methods The literature was reviewed for the use of the “no-touch” technique in procedures as varied as orthopedic fracture repair, cerebrospinal fluid shunt placement, breast reconstruction/augmentation, and penile prosthesis implantation. In addition, a single surgeon's experience with 3342 penile implant surgeries with and without the use of the “no-touch” technique was reviewed. Main outcome measure Penile implant infection rate was examined for 3342 consecutive cases between January 2002 and December 2014. Infection of standard technique was compared with rate of infection with antibiotic impregnated devices and starting in 2006 with the addition of the “no-touch” enhancement. Results Literature review revealed that the “no-touch” technique decreased postoperative cerebral shunt infection from 9.1% to 2.9%. Breast implant reconstruction surgical site infection decreased from 19% to none with the “no-touch” technique. Penile implant infection rate fell from 5.3% in 2002 to 1.99% with the use of antibiotic impregnated devices and to 0.44% with the addition of the “no-touch” technique. Conclusion Use of a “no-touch” technique involving a mechanical barrier makes a difference in preventing infection of an implantable device.

Basic neurosurgical procedures used to treat neurological conditions and emergencies include creating a burr hole, doing a craniotomy for access to the brain, laminectomy for access to the spinal cord, and placing a cerebral shunt. A burr hole is a small opening in the skull that is drilled to reach the dura mater. A craniotomy is a surgical procedure that requires removal of a piece of the skull to access the brain. Removal of the lamina of the spine (laminectomy) is done to gain access to the spinal cord. And finally, a cerebral shunt is used to transport fluids, most commonly cerebrospinal fluid (CSF), from the brain to another body cavity in order to decrease intracranial pressure (ICP). Steps involved in performing these basic neurosurgical procedures are described in this chapter.

This study described the cerebrospinal fluid (CSF) exposure of vancomycin in 8 children prescribed intravenous vancomycin therapy for cerebral ventricular shunt infection. Vancomycin CSF concentrations ranged from 0.06 to 9.13 mg/L and the CSF: plasma ratio ranged from 0 to 0.66. Two of 3 children with a staphylococcal CSF infection had CSF concentrations greater than minimal inhibitory concentration at the end of the dosing interval.

Object As part of a project to devise evidence-based safety interventions for specialty surgery, the authors sought to review current evidence in CSF shunt surgery concerning the frequency of adverse events in practice, their patterns, and the state of knowledge regarding methods for their reduction. This review may also inform future and ongoing efforts for the advancement of neurosurgical quality. Methods The authors performed a PubMed search using search terms “cerebral shunt,” “cerebrospinal fluid shunt,” “CSF shunt,” “ventriculoperitoneal shunt,” “cerebral shunt AND complications,” “cerebrospinal fluid shunt AND complications,” “CSF shunt AND complications,” and “ventriculoperitoneal shunt AND complications.” Only papers that specifically discussed the relevant complication rates were included. Papers were chosen to be included to maximize the range of rates of occurrence for the adverse events reported. Results In this review of the neurosurgery literature, the reported rate of mechanical malfunction ranged from 8% to 64%. The use of programmable valves has increased but remains of unproven benefit even in randomized trials. Infection was the second most common complication, with the rate ranging from 3% to 12% of shunt operations. A meta-analysis that included 17 randomized controlled trials of perioperative antibiotic prophylaxis demonstrated a decrease in shunt infection by half (OR 0.51, 95% CI 0.36–0.73). Similarly, use of detailed protocols including perioperative antibiotics, skin preparation, and limitation of OR personnel and operative time, among other steps, were shown in uncontrolled studies to decrease shunt infection by more than half. Other adverse events included intraabdominal complications, with a reported incidence of 1% to 24%, intracerebral hemorrhage, reported to occur in 4% of cases, and perioperative epilepsy, with a reported association with shunt procedures ranging from 20% to 32%. Potential management strategies are reported but are largely without formal evaluation. Conclusions Surgery for CSF shunt placement or revision is associated with a high complication risk due primarily to mechanical issues and infection. Concerted efforts aimed at large-scale monitoring of neurosurgical complications and consistent quality improvement within these highlighted realms may significantly improve patient outcomes.

especially in regions with irregular use of antibiotics in the general population. This study was conducted in the main refer -ral center in Tehran, Iran from April 2008 to March 2009 to identify the etiologies of shunt infections and antibiotic resistance. Patients with cerebral shunt who had been admitted to the Childrens Medical Center, Pediatrics Center of Excellence in Iran, were enrolled in this study. Cerebrospinal fluid (CSF) specimens were processed immediately by microbiological standard methods, including Gram staining and bacterial culture. Susceptibility to antibiotics was determined by diffusion method, according to CLSI standards.Fifty-seven cases with cerebral shunt and positive CSF culture were included in this study. The Gram staining was positive for 32 out of 57 subjects (56.1%). Culture identification re-vealed coagulase-negative

In The Lancet, Turgay Saritas and colleagues report a case with the valuable reminder that chronic low-grade infection of an implanted device can lead to glomerulonephritis. This complication was fi rst described 50 years ago in patients with implanted cerebral shunts, so-called shunt nephritis, but in this case was associated with a newer and increasingly widely used implanted device, the left ventricular assist device (LVAD). Such glomerulonephritis can cause relentless progressive kidney failure, even with antibiotic therapy, especially if circumstances do not allow device removal. There is, of course, nothing specifi c about the cerebral shunt; it was simply the most widely used device needing long-term placement in the circulation at the time of the fi rst report. Any indwelling artifi cial device is prone to biofi lm formation and consequent infection and recurrent bacteraemia, so chronic low-grade infection is hardly unexpected in view of the many challenges such devices pose for immunity. It is interesting to consider how the wide variety of clinical consequences from infection of such a device might refl ect diff erences in host immunity and the infecting organism. Why do some patients get overt septicaemia, whereas others develop endocarditis or abscesses in bone or soft tissues? Yet others, such as in this case, do not develop clinically apparent infection, but a chronic antibody response to the bacteraemia that is insuffi cient to clear bacterial antigens, followed by tissue injury that probably results from the formation and deposition of antigen-antibody complexes. Case Report Comment Glomerulonephritis from a chronically infected implanted device

A 70-year-old woman was examined because of increasing problems with cognition. She had a history of a cerebral shunt placed surgically 10 years previously. Introduction of Tc-99m DTPA directly into the ventricular cavity revealed good ventricular distribution, followed by progression downward, as though into a previous ventriculoperitoneal shunt. However, a chest radiograph revealed what appeared to be a shunt tube in the right atrium. Delayed lateral images showed activity in proximity to the vertebral column, indicating migration of tracer and cerebrospinal fluid into the dorsal and lumbar subarachnoid space.

Many techniques have been developed for the treatment of hydrocephalus since Kausch in 1908 (1) inserted a rubber tube from the lateral ventricle of the brain into the peritoneal cavity. Most of these techniques employ tubes of rubber, plastic material, or metal to drain cerebrospinal fluid (CSF) from the CSF space to other body cavities or into a vein. Many of these shunts require mechanical valves of plastic material or metal for both interposed along the course of the conductive tubing to promote unidirectional flow of SCF and to prevent reflux of blood or other body fluids. In consequence a large number of complications are common, such as disconnection or blocking of the tubing, valve insufficiency, bacterial colonization and outgrowing the length of the catheter (2). It has also been shown that rapid decompression following ventriculoatrial or ventriculo-peritoneal shunts may result in an epidural or subdural haematoma (30). Furthermore, the rapid removal of CSF may also cause ventricular collapse with the draining cerebral shunt catheter trapped between the abutting ventricular walls with high risk of occlusion of the catheter (4). In 1963 Scarff (2) found that the incidence of severe late complications was many times greater after most shunt operations with foreign material than after those techniques where foreign material was not introduced. All this indicates that the techniques at present in routine use are far from perfect, and that further research is required.