Shunt Overdrainage: Reappraisal of the Syndrome and Proposal for an Integrative Model

Utility of very high-pressure valves in persistent symptomatic shunt overdrainage

INTRODUCTION

Shunt overdrainage is one of the long-term complications associated with ventriculoperitoneal shunts. Treatment of refractory cases may require further upgrading of both the valve opening pressure and antisiphon device. The aim of this paper is to describe the results of this combination in a selected group of patients.

METHODS

Retrospective cohort study that included 18 pediatric patients between 2003-2022. Previous shunts were exchanged for the combination of a SOPHYSA Polaris® SPVA-300 valve and upgraded fixed or adjustable antigravitatory devices. The following variables were collected: etiology of the hydrocephalus, age at first shunt and type of valve, number of shunt revisions, other surgical procedures, age at inclusion, clinical and radiological outcomes, and follow-up time. A descriptive analysis was done with means, medians and ranges for quantitative variables; percentages and frequencies for the analysis of qualitative data.

RESULTS

The median age at first shunt was two months (0-67). The mean number of shunt revisions before inclusion was three. Shunt removal was attempted in seven patients without success; temporary success was observed in two patients who underwent ETV. Two patients had previous cranial expansions. The mean age at inclusion was 9.1 years (2.7-15.2). After the shunt system was exchanged and upgraded, clinical improvement was observed in 94.4% (17/18) of patients, and radiological improvement was observed in 83.3% (15/18) of patients. The median follow-up was 21 months.

CONCLUSIONS

Before considering more invasive therapeutic measures, shunt system optimization by the combination of very high-pressure valves and upgraded in-line antisiphon devices is a valid and safe strategy for refractory symptomatic shunt overdrainage.

VIEshunt: towards a ventricular intelligent and electromechanical shunt for hydrocephalus therapy

BACKGROUND

Shunt systems for hydrocephalus therapy are commonly based on passive mechanical pressure valves that are driven by the intracranial, intra-abdominal, and hydrostatic pressure. The differential pressure acting on the valve determines the drainage rate of cerebrospinal fluid (CSF) but is not a gauge of the physiological condition of the patient. Internal and external influences can cause over- or underdrainage and lead to pathological levels of intracranial pressure (ICP).

METHODS

The first prototype of a ventricular intelligent and electromechanical shunt (VIEshunt) is developed, tested, and compared with previous efforts towards the development of a smart shunt. Its key components are a micro pump, a flow meter, a pressure sensor, an inertial measurement unit, a wireless communication interface, and a microcontroller. The VIEshunt prototype was tested in vitro using a hardware-in-the-loop (HiL) test bench that runs real-time patient simulations involving changes in intracranial and intra-abdominal pressure, as well as changes in posture ranging between supine and upright position. The prototype was subsequently tested in an in vivo pilot study based on an acute ovine animal model (n=1) with infusions of artificial CSF.

RESULTS

During 24 h in vitro testing, the prototype detected the simulated posture changes of the patient and automatically adapted the controller reference. The posture-specific ICP references of 12 mmHg for supine and -3 mmHg for upright position were tracked without offset, thus preventing adverse over- and underdrainage during the investigated HiL test scenario. During acute in vivo testing, the prototype first regulated the mean ICP of a sheep from 22 mmHg down to 20 mmHg. Each of the three subsequent intraventricular bolus infusions of 1 mL saline solution increased mean ICP by approximately 11 mmHg. While natural absorption alone decreased ICP by only 5 mmHg within 9 min, the prototype was able to regulate ICP back to the pre-bolus pressure value within 5 min.

CONCLUSION

The developed VIEshunt prototype is capable of posture-dependent ICP regulation and CSF drainage control. Smart shunt systems based on VIEshunt could improve patient monitoring and enable optimal physiologic therapy by adapting to the individual patient. To derive statistically relevant conclusions for the performance of VIEshunt, future work will focus on the development of a next generation prototype for use in pre-clinical studies.

Long-term outcome of cerebrospinal fluid diversion in patients with intracranial germinoma at Ramathibodi Hospital

INTRODUCTION

Intracranial germinoma has a favorable prognosis with modern therapies, but the long-term outcome of cerebrospinal fluid (CSF) diversion for its associated hydrocephalus has been rarely focused on.

PURPOSE

To evaluate the long-term success of CSF diversion methods-endoscopic third ventriculostomy (ETV) versus ventriculoperitoneal (VP) shunt-in intracranial germinoma patients.

METHODS

Only pure intracranial germinomas with obstructive hydrocephalus and a minimum follow-up duration of 24 months were retrospectively reviewed. Their demographics, as well as pre-and postoperative data, were recorded. Patients were stratified into the ETV and the non-ETV groups and subsequently compared to determine the longevity and morbidity related to the procedures. Factors associated with the failure of CSF diversion were examined.

RESULTS

From 1993 to 2022, eighty-three pathologically confirmed intracranial germinomas were identified. Excluding four cases of mixed pathology, eight with incomplete data, and two with insufficient follow-up, we enrolled 69 eligible patients for analysis. Among them, forty-three cases with obstructive hydrocephalus were classified into the ETV (n = 22) and non-ETV (n = 21) groups. No intraoperative or immediate postoperative complications occurred. With a median follow-up of 101 months (IQR 77.75-139.75), the ETV group had no failures. In the non-ETV cohort (median follow-up 144 months (IQR 97-210)), two VP shunt cases (9.5%) required revision due to blockage, and two patients (9.5%) experienced transient over-drainage. These 4 patients were without long-term difficulty despite short-term cumbersome events. No significant factors predicting CSF diversion failure were identified. To date, all 43 patients are alive without metastases, maintaining a good quality of life.

CONCLUSION

This study highlights ETV as a preferred CSF diversion method in pure intracranial germinoma, achieving 100% success without morbidity. Apart from simultaneous biopsy, avoiding a separate operation, this approach eliminates shunt-related complications, ensuring long-term quality of life in patients with extraordinary prognoses from modern chemo- and radiotherapy.

The impact of architectural modifications on relative resistance to fluid flow in ventricular catheters

Introduction

Although many ventricular catheter designs exist for hydrocephalus treatment, few standardized studies assess outflow resistance and the impact of design modifications on shunt drainage. This study represents the in-vitro assessment of various architectural modifications on catheter flow rate and pressure, focusing on bulk outflow dynamics and occlusion with whole blood-inoculated cerebrospinal fluid.

Methods

Catheters were manufactured utilizing a novel catheter production setup with 16 variations from standard catheters, including but not limited to changes in: hole number, hole dimensions, catheter lumen dimension, and catheter lumen impingement. These catheters were tested in a portable custom-made ventricular catheter testing device to analyze relative resistance to flow between catheter designs. A subset of catheters with varying lumen diameters was tested in 0.30 mL/min saline flow with 2.5% blood to simulate early blood exposure.

Results

With increasing hole and lumen diameter, we found a significant decrease in overall catheter relative resistance using DIH20 (P < 0.001 and P < 0.002 respectively, n = 5). With increasing lumen diameters, blood assays showed a significant increase in the time to complete obstruction (P = 0.027, n = 5). Lumen impingement, representing one obstruction-based pinch point in the lumen, showed a considerable increase in relative resistance as obstruction diameter increased and lumen diameter at the pinch point decreased (P = 0.001, n = 5). Removal of specific catheter hole rows trended toward an increase relative resistance after 75% of catheter holes were blocked, but the effect in relative outflow resistance is otherwise minimal (P > 0.05, n = 5) and no effect was observed with blocking segments.

Conclusion

This study implemented a novel method of rapid catheter manufacturing to systematically produce ventricular catheters with specific catheter architecture. By testing variables independently, we found that catheters with changes to the lumen diameter had the most dramatic shifts in overall relative resistance between catheter designs. Similarly, testing in the acute in-vitro blood assay demonstrated that smaller diameter catheters have a higher propensity to obstruct with blood compared to catheters with larger diameter. Relative resistance impacts fluid outflow efficiency, which may translate to clinical outcomes for hydrocephalus patients. These findings help us understand catheter architectural effects on resistance and inform future designs for specific ventricle morphologies.

Comparative Efficacy of Ventriculosubgaleal Shunt Versus Ventricular Reservoir in Achieving Shunt Independence for Infants With Posthemorrhagic Hydrocephalus by 6 Months

BACKGROUND AND OBJECTIVES

Low-birth weight, premature infants often have severe intraventricular hemorrhage (IVH), which can result in posthemorrhagic hydrocephalus (PHH), sometimes requiring cerebrospinal fluid diversion. Initial temporizing management of PHH includes placement of a ventriculosubgaleal shunt (VSGS) or ventricular access device (VAD). Studies have found similar permanent shunt conversion rates between VSGS and VAD but were limited by sample scope and size. The rate of conversion to permanent shunt within 6 months post-IVH in premature infants, comparing the efficacy of VSGS and VAD, remains underexplored.

METHODS

This retrospective study used International Classification of Diseases-10 codes in the PearlDiver Mariner database to analyze the medical records of premature infants diagnosed with grade 3 or 4 IVH who underwent VAD or VSGS treatment. A 2:1 matching process was used to control demographics, IVH severity, degree of prematurity, and associated respiratory or gastrointestinal conditions. We assessed the rates and odds of conversion to permanent shunts within 6 months, using Kaplan-Meier plots for shunt-free probability and log-rank tests for distribution comparisons.

RESULTS

Our matched analysis included 222 infants (VAD, n = 145, VSGS, n = 77) and demonstrated no difference in the proportion of gender, respiratory conditions, necrotizing enterocolitis, extreme prematurity, and Grade III or IV IVH. The odds of requiring a permanent shunt were significantly lower in the VSGS group compared with the VAD group within 6 months (odds ratio: 0.22, 95% CI [0.12, 0.41], P < .001). From day 60 onward, Kaplan-Meier plots indicated a notable divergence in shunt-free probability within 6 months (Log-Rank P < .001).

CONCLUSION

This study highlights a significant reduction in the need for permanent shunt placement within 6 months for post-IVH in premature infants who underwent VSGS vs VAD, suggesting that VSGS may be a more favorable temporizing procedure for managing PHH in this vulnerable population.

Case report: CSF hypotension secondary to a free syringo-subarachnoid-peritoneal shunt

INTRODUCTION

Syringomyelia is present in 40% of pediatric patients with Chiari malformation. Typically treated with posterior fossa decompression, some cases require further intervention such as syrinx shunting.

CASE REPORT

We report a 16-year-old female with Chiari type 1 malformation and syringomyelia who underwent posterior fossa decompression and subsequent free syringo-subarachnoid-peritoneal shunting. The patient developed symptoms of CSF overdrainage, and imaging indicated CSF hypotension. A distal catheter ligation temporarily improved symptoms, but eventually, a programmable ventricular shunt was necessary due to shunt dependence.

CONCLUSION

This case highlights the rare complication of CSF overdrainage from syrinx shunting and the importance of shunt selection considerations.

Collapse or distention of the perioptic space in children - What does it mean to pediatric radiologists? Comprehensive review of perioptic space evaluation

The perioptic space comprises the subarachnoid space [SAS] of the optic nerve communicating with the SAS of the central nervous system. Pressure variations in the SAS of the central nervous system can be transmitted to the optic papilla through the perioptic space. Variations in the diameter of the perioptic space serve as an important indicator for select intracranial pathologies in the pediatric population. Though the perioptic space can be evaluated using various imaging modalities, MRI is considered highly effective due to its superior soft tissue resolution. With advancement in MR imaging techniques, high-resolution images of the orbits can provide improved visualization of the perioptic space. It is imperative for the pediatric radiologist to routinely assess the perioptic space on brain and orbit MR imaging, as it can prompt exploration for additional features associated with select intracranial pathologies, thus improving diagnostic accuracy. This article reviews basic anatomy of the perioptic space, current understanding of the CSF dynamics between the perioptic space and central nervous system SAS, various imaging modalities utilized in the assessment of the perioptic space, MRI sequences and the optimal parameters of specific sequences, normal appearance of the perioptic space on MR imaging, and various common pediatric pathologies which cause alteration in the perioptic space.

Paediatric hydrocephalus

Hydrocephalus is classically considered as a failure of cerebrospinal fluid (CSF) homeostasis that results in the active expansion of the cerebral ventricles. Infants with hydrocephalus can present with progressive increases in head circumference whereas older children often present with signs and symptoms of elevated intracranial pressure. Congenital hydrocephalus is present at or near birth and some cases have been linked to gene mutations that disrupt brain morphogenesis and alter the biomechanics of the CSF-brain interface. Acquired hydrocephalus can develop at any time after birth, is often caused by central nervous system infection or haemorrhage and has been associated with blockage of CSF pathways and inflammation-dependent dysregulation of CSF secretion and clearance. Treatments for hydrocephalus mainly include surgical CSF shunting or endoscopic third ventriculostomy with or without choroid plexus cauterization. In utero treatment of fetal hydrocephalus is possible via surgical closure of associated neural tube defects. Long-term outcomes for children with hydrocephalus vary widely and depend on intrinsic (genetic) and extrinsic factors. Advances in genomics, brain imaging and other technologies are beginning to refine the definition of hydrocephalus, increase precision of prognostication and identify nonsurgical treatment strategies.

Chronic Pediatric Headache as a Manifestation of Shunt Over-Drainage and Slit Ventricle Syndrome in Patients Harboring a Cerebrospinal Fluid Diversion System: A Narrative Literature Review

The main subject of the current review is a specific subtype of headache, which is related to shunt over-drainage and slit ventricle syndrome, in pediatric patients harboring an implanted shunt device for the management of hydrocephalus. This clinical entity, along with its impairment regarding the quality of life of the affected individuals, is generally underestimated. This is partly due to the absence of universally agreed-upon diagnostic criteria, as well as due to a misunderstanding of the interactions among the implicated pathophysiological mechanisms. A lot of attempts have been performed to propose an integrative model, aiming at the determination of all the offending mechanisms of the shunt over-drainage syndrome, as well as the determination of all the clinical characteristics and related symptomatology that accompany these secondary headaches. This subcategory of headache, named postural dependent headache, can be associated with nausea, vomiting, and/or radiological signs of slim ventricles and/or subdural collections. The ultimate goal of our review is to draw clinicians' attention, especially that of those that are managing pediatric patients with permanent, long-standing, ventriculoperitoneal, or, less commonly, ventriculoatrial shunts. We attempted to elucidate all clinical and neurological characteristics that are inherently related to this type of headache, as well as to highlight the current management options. This specific subgroup of patients may eventually suffer from severe, intractable headaches, which may negatively impair their quality of daily living. In the absence of any other clinical condition that could be incriminated as the cause of the headache, shunt over-drainage should not be overlooked. On the contrary, it should be seriously taken into consideration, and its management should be added to the therapeutic armamentarium of such cases, which are difficult to be handled.

Risk factors, treatment, and outcome in dogs and cats with subdural hematoma and hemispheric collapse after ventriculoperitoneal shunting of congenital internal hydrocephalus

BACKGROUND

Overshunting and hemispheric collapse are well-known complications after ventriculoperitoneal shunt (VPS) implantation. Risk factors that predispose to overshunting, treatment options, and prognosis after therapeutic intervention have not been described.

HYPOTHESIS/OBJECTIVES

To identify preoperative risk factors for overshunting, the effect of surgical decompression, and their outcomes.

ANIMALS

Seventy-five dogs and 7 cats.

METHODS

Retrospective case cohort study. Age, breed, sex, body weight, number of dilated ventricles, ventricle brain ratio, intraventricular pressure, and implanted pressure valve systems were evaluated as possible risk factors.

RESULTS

Overshunting had a prevalence of 18% (Cl 95% 9.9-26.66). An increase of 0.05 in VBR increased the risk of overshunting by OR 2.23 (Cl 95% 1.4-3.5; P = .001). Biventricular hydrocephalus had the highest risk for overshunting compared to a tri- (OR 2.48 with Cl 95% 0.5-11.1) or tetraventricular hydrocephalus (OR 11.6 with Cl 95% 1.7-81.1; P = .05). There was no influence regarding the use of gravitational vs differential pressure valves (P > .78). Overshunting resulted in hemispheric collapse, subdural hemorrhage, and peracute deterioration of neurological status in 15 animals. Subdural hematoma was removed in 8 dogs and 2 cats with prompt postoperative improvement of clinical signs.

CONCLUSIONS AND CLINICAL IMPORTANCE

Biventricular hydrocephalus and increased VBR indicate a higher risk for overshunting. The use of differential valves with gravitational units has no influence on occurrence of overshunting related complications and outcomes. Decompressive surgery provides a favorable treatment option for hemispheric collapse and has a good outcome.

Preterm-related posthemorrhagic hydrocephalus: Review of our institutional series with a long-term follow-up

INTRODUCTION

Preterm-related posthemorrhagic hydrocephalus is a major cause of neurological impairment and a common indication for a ventriculoperitoneal shunt in infants that are prone to diverse complications. Protocols of diagnosis and treatment are in continuous evolution and require evaluation of their results.

OBJECTIVE

To review the clinical characteristics and results of a series of preterm-related posthemorrhagic hydrocephalus needing a definitive shunt from 1982 to 2020 in our institution. As a secondary objective we evaluated the safety of the changes in our protocol of treatment from 2015.

METHODS

Retrospective review, clinical investigation.

RESULTS

133 patients were implanted a shunt in the study period. Shunt infection was diagnosed in 15 patients. Proximal shunt obstruction as the first complication was diagnosed in 30% of cases at one year, 37% at two years and 46% at five years. 61 patients developed very small or collapsed ventricles at last follow-up. Two thirds of our patients achieved normal neurological development or mild impairment. Changes in protocol did not significantly modify clinical results although improvement in most outcomes was observed. Mean follow-up was over nine years.

CONCLUSIONS

Clinical outcomes are comparable to previous reported data. Changes in protocol proved to be safe and improved our results. Programmable shunts can be used safely in preterm patients although they may not prevent tendency towards ventricular collapse, which is very common after long follow-up.

How to define CSF overdrainage: a systematic literature review

PURPOSE

Overdrainage (OD) is one of the most frequent complications related to drainage of the cerebrospinal fluid (CSF). It is mostly associated with valve-bearing shunt systems but should probably be considered as a risk factor in any type of CSF diversion procedure. There is extreme variation in the reported incidence of OD due to the lack of consensus on defining criteria and an unclear perception of the pathophysiology. Hence, OD is probably underreported and underestimated. The objective of this paper was to establish a definition of OD, based on a systematic review of the literature.

METHODS

A systematic search was conducted in MEDLNE and EMBASE. Studies providing a definition or a description of diagnostic findings related to OD in ventriculoperitoneal shunt treated hydrocephalus were included. Non-English titles, abstracts and manuscripts were excluded. Extracted descriptions were graded into five groups (class I-V studies) based on how precise the terminology used to describe OD was. Class I studies were included for further analysis and characteristics of OD were extracted. The quality of included descriptions was assessed by a clinical expert panel.

RESULTS

A total of 1309 studies were screened, 190 were graded into groups, and 22, which provided specific definitions or descriptions of OD, were graded as class I studies. We extracted 32 different characteristics consistent with OD (e.g., clinical symptoms, radiological signs, and syndromes).

CONCLUSION

There was an overall agreement that CSF overdrainage following implantation of a ventriculoperitoneal shunt in a mixed pediatric and adult population is characterized as a persistent condition with clinically manifestations as postural dependent headache, nausea, and vomiting and/or radiological signs of slim ventricles and/or subdural collections.

External-internal cranial expansion to treat patients with craniocerebral disproportion due to post-shunt craniosynostosis: a case series

INTRODUCTION

Secondary craniosynostosis subsequent to shunting is one of the late complications of ventricular shunt placement in the early childhood. Several interventions have been used to treat high intracranial pressure associated with this condition. This study aimed to evaluate the patients' clinical symptoms and head circumference before and after a method of decompressive craniotomy, coined as external-internal cranial expansion (EICE).

METHODS

A retrospective study was conducted, and the patients who had undergone EICE for the treatment of post-shunt craniosynostosis between 2010 and 2020 were enrolled. This approach was a combination of a hinge multiple-strut decompressive craniectomy and internal cranial flap thinning by drill. Data, extracted from medical records, were used to evaluate the patients' symptoms and head circumferences before and 12 months after surgery.

RESULTS

A total of 16 patients were enrolled in the study, of which eight were females. Before the surgery, 9 patients (56.2%) suffered from visual impairment, and all had intractable headache. Papilledema was recorded in all, with 3 cases having optic disc paleness. After cranial expansion, only two patients had headaches, diagnosed as migraine-type and psychosomatic headaches, respectively. In two patients, progressive visual impairments got worsening after surgery, which would be due to severe preoperative optic nerve atrophy. Patients' head circumferences significantly increased after the surgery (mean of 48.97 ± 4.28 cm vs. 45.78 ± 4.31 cm; P value < 0.0001).

CONCLUSION

In lower resource countries, where newer technologies like distraction osteogenesis is not easily available, external-internal cranial expansion can be considered an effective alternative for patients with post-shunt craniosynostosis.

Incidental and Clinical Significance of Slit Ventricles in Fixed Pressure Valves

INTRODUCTION

Slit ventricle syndrome (SVS) is a recognized delayed complication of cerebrospinal fluid (CSF) shunting in children. It had been linked to the use of low-pressure shunts and considered an argument for the use of programmable valves. In this study, we aim to assess the rate of SVS in children that were shunted using fixed-pressure valves.

METHODOLOGY

This study is a retrospective cohort study that occurred in King Abdulaziz Medical City, Jeddah, which reviews 100 patients with a median age of 15.5 months that were shunted by using fixed pressure valves during the period from 2010 to 2018. Fixed low-pressure valves were used in 69% of patients, while fixed medium-pressure valves were used in 31% of patients. SVS was defined by the presence of slit-like ventricles (fronto-occipital [F-O] horns ratio was ≤ 0.2 on any post-shunt CT scan) and the occurrence of slit-like ventricle-related symptoms (chronic headache, nausea, vomiting, and altered conscious level_ in the absence of other causes of shunt malfunction.

RESULTS

The overall SVS rate in the cohort was 6%. Nine children had slit-like ventricles, but only six of them were symptomatic. Relatively higher SVS rates were observed in younger male children, obstructive hydrocephalus, and medium-pressure valves. Slit-like ventricle-related symptoms in the absence of a slit-like ventricle were reported in 24 out of 91 (26%) patients. A total of 42 patients underwent shunt revisions for other complications. All SVS patients were treated conservatively. There was a temporal fluctuation in the F-O horns ratio and in some patients with SVS their F-O horns ratio returned to normal at further follow-up without intervention.

CONCLUSIONS

The overall SVS rate following the use of fixed-pressure CSF valves in children is low and managed conservatively. Not all patients with slit-like ventricles are symptomatic and the radiological appearance of SVS may improve on further follow-up without intervention. Fixed pressure valves remain an acceptable device in the treatment of hydrocephalus in children.

Current perspectives on the recognition and diagnosis of low CSF pressure headache syndromes

INTRODUCTION

Headaches occur when cerebrospinal fluid (CSF) pressure drops following dural puncture or trauma or spontaneously. As the features of these headaches and their accompanying symptoms might not be typical, low CSF pressure headache syndromes, and spontaneous intracranial hypotension in particular, are often misdiagnosed and underdiagnosed.

AREAS COVERED

The aim of this narrative review is to summarize the most recent evidence regarding the clinical presentation and the diagnosis of low CSF pressure headache syndromes.

EXPERT OPINION

The clinical spectrum low CSF pressure headache syndromes varies significantly and key signs might be missing. Low CSF pressure headache syndromes should be included in the differential diagnosis of any case of refractory headache, even when the headache is not orthostatic, or there are normal neuroimaging findings, and/or lumbar puncture opening pressure is within normal limits. Future research should focus on controlled interventional studies on the treatment of low CSF pressure headache syndromes, which are currently lacking.

A case of hydrocephalus confounded by suprasellar arachnoid cyst and concomitant reversible cerebral vasoconstriction syndrome

Background:

Obstructive hydrocephalus is a neurologic condition that has varied clinical and imaging presentations, as well as a multitude of congenital etiologies including aqueductal stenosis and less commonly arachnoid cysts. Aqueductal stenosis is a physical limitation to cerebrospinal fluid flow along the course of the aqueduct, which results in enlargement of the third and lateral ventricles. Arachnoid cysts are thin walled and fluid filled central nervous system lesions that can result in mass effect on adjacent structures. While arachnoid cysts are mostly asymptomatic, they may present with neurological symptoms that vary depending on the location of the lesion. Suprasellar cysts in particular may cause obstructive hydrocephalus as well as endocrine dysfunction. Reversible cerebral vasoconstriction syndrome (RCVS) is an unusual condition caused by cerebral arterial vasoconstriction that often presents initially with a thunderclap headache. Frequently, there is some environmental trigger associated with this condition. RCVS more commonly affects women and can induce stroke.

Case Description:

A 57-year-old female presented to the emergency department with progressive headache and visual changes. Initial workup suggested the patient’s symptoms where related to RCVS but subsequent surgical management of what was presumed to be long standing, compensated hydrocephalus resulted in resolution of the patient’s symptoms.

Conclusion:

We report, to the best of our knowledge, the first case of aquedutal stenosis and suprasellar arachnoid cyst with concomitant RCVS. The presence of multiple pathologies found on radiologic imaging illustrates the challenges presented by incidental findings and subsequent anchoring bias in medical diagnosis.

The Role of Antisiphon Devices in the Prevention of Central Ventricular Catheter Obliteration for Hydrocephalus: A 15-Years Institution's Experience Retrospective Analysis

Shunt over-drainage in patients harboring a ventriculoperitoneal shunt constitutes one of the most devastating, and difficult to manage, side effects associated with this operation. Siphoning is one of the most important contributing factors that predispose to this complication. Based on the fact that the predisposing pathophysiologic mechanism is considerably multiplicated, amelioration of that adverse condition is considerably difficult to achieve. A lot of evidence suggests that the widespread utilization of gravitational valves or antisiphon devices is of utmost importance, in order to minimize or even avoid the occurrence of such complications. The recent literature data highlight that gravity-related, long-lasting shunt over-drainage consists of a momentous factor that could be considered one of the main culprits of central shunt failure. A lot of efforts have been performed, in order to design effective means that are aimed at annihilating siphoning. Our tenet was the investigation of the usefulness of the incorporation of an extra apparatus in the shunt system, capable of eliminating the impact of the siphoning effect, based on the experience that was gained by their long-term use in our institution. A retrospective analysis was performed, based on the data that were derived from our institution’s database, centered on patients to which an ASD was incorporated into their initial shunt device between 2006 and 2021. A combination of clinical, surgical, radiological findings, along with the relevant demographic characteristics of the patients were collected and analyzed. We attempted to compare the rates of shunt dysfunction, attributed to occlusion of the ventricular catheter, in a group of patients, before and after the incorporation of an anti-siphon device to all of them. A total number of 120 patients who have already been shunted due to hydrocephalus of different etiologies, were managed with the insertion of an ASD. These devices were inserted at different anatomical locations, which were located peripherally to the initially inserted valvular mechanism. The data that were collected from a subpopulation of 17 of these patients were subjected to a separate statistical analysis because they underwent a disproportionately large number of operations (i.e., >10-lifetime shunt revisions). These patients were studied separately as their medical records were complicated. The analysis of our records revealed that the secondary implementation of an ASD resulted in a decrease of the 1-year and 5-year central catheter dysfunction rates in all of our patients when compared with the relevant obstruction rates at the same time points prior to ASD insertion. According to our data, and in concordance with a lot of current literature reports, an ASD may offer a significant reduction in the obstruction rates that is related to the ventricular catheter of the shunt. These data could only be considered preliminary and need to be confirmed with prospective studies. Nevertheless, this study could be considered capable of providing supportive evidence that chronic shunt over-drainage is a crucial factor in the pathophysiology of shunt malfunction. Apart from that, it could provide pilot data that could be reviewed in order to organize further clinical and laboratory studies, aiming toward the assessment of optimal shunt valve systems that, along with ASD, resist siphoning.

Differential Diagnosis of Cyclic Vomiting and Periodic Headaches in a Child with Ventriculoperitoneal Shunt: Case Report of Chronic Shunt Overdrainage

Fourteen months after the implantation of a ventriculoperitoneal shunt catheter, a six-year-old boy developed recurrent, severe headaches and vomiting every three weeks. The attacks were of such severity that hospitalizations for analgesic and antiemetic therapies and intravenous rehydration and electrolyte substitution were repeatedly required. The patient was asymptomatic between the attacks. After an extensive diagnostic workup-including repeated magnetic resonance imaging (MRI) and neurosurgical examinations-common differential diagnoses, including shunt overdrainage, were ruled out. The patient was transferred to a specialized pediatric pain clinic with suspected cyclic vomiting syndrome (CVS). Despite intensive and in part experimental prophylactic and abortive pharmacological treatment, there was no improvement in his symptoms. Consecutive MRI studies reinvestigating the initially excluded shunt overdrainage indicated an overdrainage syndrome. Subsequently, the symptoms disappeared after disconnecting the shunt catheter. This case report shows that even if a patient meets CVS case definitions, other differential diagnoses must be carefully reconsidered to avoid fixation error.

About gladiators and a sacred disease

In this special edition of the Biomedical Journal the reader gains an insight into drug-resistant epilepsy and according treatment approaches involving deep brain stimulation, the ketogenic diet and fecal microbiota transplant. Another emphasis is put on personalized medicine strategies, and covered in articles about the use of natriuretic peptides against cancer, along with an article about companion diagnostics involving extracellular vesicles. Recurrent infection with Clostridium difficile, associated risk factors and therapeutic options are discussed. We learn about a mechanism that helps Leishmania evade a host control mechanism, receive an update about human adenovirus and are presented with characteristic magnetic resonance neuroimaging in COVID-19 pediatric patients. An advanced assessment in pediatric septic shock and an improved model for a pediatric early warning system are proposed. Some of the genetic causes of renal hypomagnesemia are explored, the impact of air pollution on children is examined, and an antisiphon device is described for surgical treatment of hydrocephalus. The relation between energy metabolism, circadian rhythm and its influence on the ATPase in the SCN are investigated, and among others some of the genetics influencing smoking duration and lung cancer. Finally it is discussed how embryo quality can be improved in in vitro fertilization, and what impact high estradiol has on blastocyst implantation. The outcome of surgery to correct mandibular deficiency is assessed, and in two letters the inclusion of observational studies in the evaluation of clinical trials related to COVID-19 is elaborated.