Shunt Disconnection Research Articles

Mechanical shunt failure in hydrocephalus: a common but remediable complication with technical nuances

BackgroundA ventriculoperitoneal (VP) shunt is a cerebral shunt that diverts excess cerebrospinal fluid (CSF).Obstruction in the normal outflow or decreased absorption of the fluid is the usual cause. Hydrocephalus is treated by cerebral shunts.In paediatric patients, untreated hydrocephalus can be lethal and leads to many adverse effects including increase irritabilities, chronic headaches, learning difficulties, visual disturbances, and, in more advanced cases, severe mental retardation. Malfunction of the shunt with excess CSF accumulated can increase the intracranial pressure resulting in cerebral oedema and ultimately herniation.ObjectiveTo study and evaluate the mechanical causes of shunt failure and their surgical remedies and reduce the preventable morbidity, cost and mortality associated with shunt failure.MethodsWe conducted a prospective observational study including 70 patients who developed pure mechanical shunt failure for the first time from 2017 to 2020 in the Department of Neurosurgery Sher-i-kashmir Institute of Medical Sciences. Patients with previous shunt surgeries which include VP shunting and shunt revision or failure and shunt infections were excluded. Identity of all the patients has been kept anonymus. Written informed consent was obtained from all patients or their guardians in case of minors. Shunt malfunction was in the form of catheter misplacement, kinking, displacement from the ventricle or peritoneal cavity, disconnection, migration,inadvertent suturing of the catheter, air in shunt bulb.ResultsWe found kinking at the proximal end in 25 (35%) patients as the most common cause of shunt failure. It was mostly as a result of inadequate and less spacious tunnelling made for the reservoir. Inadvertant suturing of shunt while closing abdomen in 7 (10%), shunt disconnection in 6 (8.5%), air in shunt bulb in 2 (2.8%), wrong placement at ventricular end in 10 (14.2%), shunt migration into the brain parenchyma in 5 (7.1%), shunt migration through the anal canal in 1(1.4%), pseudomeningocele around catheter valve in 3 (4.2%), placement of lower end into the preperitoneal space in 4 (5.7%) patients.ConclusionsShunt surgery is seemingly a straightforward operation for neurosurgeons. But considering the incidence of shunt failure and its associated morbidity and mortality, it should always be done with trepidation and extreme caution. Exclusive mechanical shunt malfunction is a major concern and leads to great deal of morbidity in the shunt operations. However, there are trivial remedies and technical nuances which needs to be followed during surgery to avoid these complications.

The clinical spectrum and management outcome of adult-onset aqueductal stenosis: Insight from South-West Nigeria.

Adult-onset aqueductal stenosis (AOAS) is an uncommon cause of hydrocephalus in adults. Its etiopathogenesis is poorly understood, with various proposed mechanisms, spectrum of presentation, and management. Very little has been reported on this anomaly in African literature. This study aimed to describe the pattern of presentation, clinical spectrum, and early outcomes following the shunt procedure in our population practice setting. This was a retrospective case series of patients with non-tumoral AOAS managed between 2008 and 2023 in a tertiary center in South-West Nigeria. Relevant demographic, clinical-radiologic, and outcome data were retrieved and analyzed. There were seven males and one female. Their age ranged from 18 to 50 years. The duration of symptoms ranged from 3 to 120 months. All patients admitted having headaches; however, visual deterioration (n = 5) was the most common presenting symptom. Features of endocrinopathy (n = 1), cerebellar dysfunction (n = 2), cognitive deficit (n = 2), spontaneous cerebrospinal fluid leak (n = 1), and sphincteric dysfunction (n = 1) were also observed. The mean Evan's index at the presentation was 0.43. Ventriculoperitoneal shunt (VPS) insertion was performed in seven patients with good outcomes. One patient opted for a referral. One patient had shunt revision 6 years later on account of shunt disconnection. AOAS is an infrequent cause of hydrocephalus in our setting, with most patients seeking medical consultation following visual deterioration. Proper evaluation of adults with long-standing headaches and associated features is advocated to avert total visual loss in this subgroup. VPS insertion is a viable treatment option with a good outcome.

839 Techniques for Management and Avoidance of Ventriculo Artrial Shunt Distal Catheter Complications

INTRODUCTION: Minimizing the risk of distal ventriculatrial (VA) shunt disconnection is particularly important due to the risk of catheter embolization. This rare event occurs in approximately 1.56% of implanted VA shunts. There are no clear treatment guidelines in the literature to help prevent and manage this complication. The use of a connector in the neck has been implicated in mechanical failures of ventriculoperitoneal (VP) shunts;2however, to the best of our knowledge, there was no literature describing disconnection and migration of distal VA shunt catheters due to use of a connector. METHODS: Clinical records for a single institution between 2010 and 2021 were reviewed for instances of distal catheter disconnection and migration. RESULTS: All three instances of distal disconnection were associated with use of a connector in the neck that resulted in fracture of the catheter due to repetitive sheering forces. In all three cases, the distal catheter was retrieved via an endovascular approach in conjunction with transesophageal echocardiography to assess for retrieval feasibility. An additional case is included where the distal catheter is abandoned due to adhesions and the patient was placed on anticoagulation. CONCLUSIONS: We recommend the avoidance of a straight connector when performing VA shunt placement. Catheter removal requires a multidisciplinary approach to best reduce risk of complications.

Portosystemic encephalopathy with hepatitis C cirrhosis after achieving SVR managed by percutaneous transhepatic shunt obliteration and portal systemic shunt disconnection

Portosystemic encephalopathy with hepatitis C cirrhosis after achieving SVR managed by percutaneous transhepatic shunt obliteration and portal systemic shunt disconnection

Investigation of ventriculoperitoneal shunt disconnection for hydrocephalus treatment.

This investigation is aimed at gaining a better understanding of the factors that lead to mechanical failure of shunts used for the treatment of hydrocephalus, including shunt catheter-valve disconnection and shunt catheter fracture. To determine the root cause of mechanical failure, the authors created a benchtop mechanical model to mimic mechanical stressors on a shunt system. To test shunt fracture, cyclical loading on the catheter-valve connection site was tested with the shunt catheter held perpendicular to the valve. Standard methods were used to secure the catheter and valves with Nurolon. These commercial systems were compared to integrated catheters and valves (manufactured as one unit). To test complete separation/disconnection of the shunt catheter and valve, a parallel displacement test was conducted using both Nurolon and silk sutures. Finally, the stiffness of the catheters was assessed. All mechanical investigations were conducted on shunts from two major shunt companies, assigned as either company A or company B. Cyclical loading experiments found that shunts from company B fractured after a mean of 4936 ± 1725 cycles (95% CI 2990-6890 cycles), while those of company A had not failed after 8000 cycles. The study of parallel displacement indicated complete disconnection of company B's shunt catheter-valve combination using Nurolon sutures after being stretched an average 32 ± 5.68 mm (95% CI 25.6-38.4 mm), whereas company A's did not separate using either silk or Nurolon sutures. During the stiffness experiments, the catheters of company B had statistically significantly higher stiffness of 13.23 ± 0.15 N compared to those of company A, with 6.16 ± 0.29 N (p < 0.001). Mechanical shunt failure from shunt catheter-valve disconnection or fracture is a significant cause of shunt failure. This study demonstrates, for the first time, a correlation between shunt catheters that are less mechanically stiff and those that are less likely to disconnect from the valve when outstretched and are also less likely to tear when held at an angle from the valve outlet. The authors propose an intervention to the standard of care wherein less stiff catheters are trialed to reduce disconnection.

Shunt disconnection is less likely using a surgeon’s knot compared with a surgical constrictor knot

Introduction Ventriculo-peritoneal shunt malfunction is a common neurosurgical presentation, which may occur as a result of shunt disconnection at the level of the valve. Previous studies assessing ligatures have suggested that the constrictor knot is stronger in securing a ligature compared to the surgeon’s knot. Our study compared the ability of each knot to secure shunt tubing to the valve. Methods A medtronic shunt valve was secured to a peritoneal catheter using the surgeon’s knot versus constrictor’s knot. The weight and subsequent force (N) required to pull off the shunt tubing at the knot site were recorded. Results The mean pull-off force was 11.7 N for the surgeon knot, and 8.9 N for the constrictor knot. There was significant difference in favour for the surgeon’s knot compared to the constrictor knot. Conclusions The surgeon’s knot is significantly stronger than the constrictor knot for securing a peritoneal catheter to a CSF shunt valve.

Three-Dimensional Computed Tomography Reconstruction Unmasks Shunt Disconnection in a Child

Three-Dimensional Computed Tomography Reconstruction Unmasks Shunt Disconnection in a Child

Patent persistent fibrous tract in a patient with disconnected lumboperitoneal shunt

Disconnection of proximal or distal catheter is seen more frequently in the complication of the lumboperitoneal (LP) shunt. A connective tissue sheath that forms around the peritoneal catheter of silicone shunt tubing is a normal biological response to foreign material. The literature did not establish whether the disconnected LP shunt can allow passage of cerebrospinal fluid (CSF) through the disconnected portion. However, proof of the passage of CSF through these sheaths has been reported in only one published study to date. We present a case of a young patient with disconnected LP shunt who reported patent persistent fibrous tract around the tube shunt. In conclusion, asymptomatic patients with shunt disconnection should be evaluated with shuntography for patency of fibrous sheath before removal of the shunt to avoid the possible complications.

Use of EOS Low-Dose Biplanar X-Ray for Shunt Series in Children with Hydrocephalus: A Preliminary Study

Shunt series (SS) are a common diagnostic tool used to verify shunt integrity. SS include X-ray films of the skull, chest, and abdomen and often are performed either when a shunted patient presents with suspected shunt malfunction or as a screening test to identify shunt disconnections or dislodgment. EOS low-dose biplanar X-rays are associated with significantly reduced radiation doses compared with ordinary X-rays and are used for various indications. This is the first publication on the use of EOS as a SS technique. Over a period of 6 months, EOS were performed at our center for various orthopedic indications, mostly for scoliosis evaluation. Nine children (<20 years of age) had a ventriculoperitoneal shunt and served as the study group. We retrospectively reviewed shunt visibility and integrity in the EOS scans as well as regular SS or plain spinal X-rays. Three patients had bilateral shunts, and 8 had previous X-rays for comparison. In all patients, the shunt integrity was easily demonstrated on the EOS images. Two patients had an identified shunt disconnection confirmed on the EOS images. No shunt-related information was missed on the EOS compared with the other X-ray images. These preliminary results suggest that EOS may be used as an alternative technology to demonstrate shunt integrity instead of regular X-ray SS. Favorable shunt visibility without the need for multiple radiation exposures and image processing (such as stitching) results in a significantly shorter examination time and significant less radiation.

Ventriculoperitoneal Shunt Disconnection Associated with Loss of Consciousness in a Child Patient: A Case Report and Review of Intra-Abdominal Complications of Vp Shunts

Ventriculoperitoneal Shunt Disconnection Associated with Loss of Consciousness in a Child Patient: A Case Report and Review of Intra-Abdominal Complications of Vp Shunts

The disconnected shunt: a window of opportunities.

Shunt disconnection (SD), or migration of the distal end to extra-peritoneal tissues, may lead to shunt malfunction or be diagnosed incidentally. We present a systematic approach for treatment options that is tailored to each patient's personalized history, CSF physiology, and distribution (MRI), as well as a careful informed consent process. We present two algorithms, for symptomatic and asymptomatic SD. In cases presenting with symptomatic elevated intracranial pressure, a distal shunt revision (DSR), or, in selected patients, an endoscopic third ventriculostomy (ETV), should be performed. In asymptomatic patients, several options exist. The first decision is whether to intervene or follow. When action is recommended, a planned shunt revision is possible. The other option is to externalize the shunt and close it under careful clinical and radiological follow-up. Patients are then stratified to three main groups-those that are not shunt dependent, those that have radiological evidence of obstructed hydrocephalus, and the remaining patients. Patients are accordingly treated by ligation of the shunt without or with an endoscopic third ventriculostomy or with a distal shunt revision. Twenty-one patients were diagnosed with a shunt disconnection. Seventeen were diagnosed at screening tests, while four were presented with shunt malfunction symptoms. Sixteen incidental cases were followed (3-111months, 39±37), of which three became symptomatic. One patient had an elective ETV followed by a DSR, and three followed-up patients became symptomatic and thus underwent surgery. All symptomatic patients underwent treatment (5 DSR, 2 ETV). Shunt disconnection opens a window of opportunities into better understanding the pathophysiology of the hydrocephalic process in a specific patient. Distal shunt revision or ETV (in selected patients) is indicated in symptomatic cases. In asymptomatic patients, options exist. Choosing between those options mandates a careful individual assessment and a detailed informed consent process.

Intermittent entrapment of choroid plexus in ventricular catheter

Abstract Ventriculoperitoneal (VP) shunt placement remains the primary treatment option for most cases of pediatric hydrocephalus. However, these devices have a relatively high complication with malfunction commonly attributed to proximal catheter occlusion. Factors augmenting shunt malfunction include infection, valve failure, proximal or distal catheter obstruction, distal catheter migration, shunt disconnection. In this case report, we describe the perioperative course of a neonate with communicating hydrocephalus who required a VP shunt, with real time sonographic documentation of the transient occlusion of the ventricular catheter tip by choroid plexus immediately after surgery.

Case Report of a V-P Shunt Dependent Child with Shunt Disconnection and Infection with Extended-Spectrum beta-Lactamase-Producing Klebsiella pneumoniae (ESBL-KP)

Shunt malfunction superadded with infection in a shunt dependent child always lead to significant mortality and morbidity. Infections of central nervous system with Extended-Spectrum β-Lactamase-Producing Klebsiella pneumoniae (ESBL-KP) are very atypical, only occurs in immunosuppressive state and inappropriate treatment increases mortality and morbidity. Use of central catheter or ‘ommaya reservoir’ is a very good method of C.S.F drainage and intraventricular administration of some antibiotics. Here we report a shunt dependent baby of three and half years with history of recurrent respiratory tract infections, gastroenteritis and UTIs as she presented to us with shunt disconnection and simultaneous meningitis with Extended-Spectrum β-Lactamase- Producing Klebsiella pneumoniae (ESBL-KP). This patient was treated with removal of infected shunt, reservoir implantation, parenteral antibiotics and lastly reintroduction of V-P shunt with removal of ‘ommaya reservoir’.

Ventriculoperitoneal Shunt Complications in a Developing Country: a Single Institution Experience

Shunting a hydrocephalus is among the most commonly performed neurosurgical procedures. Hydrocephalus constitute a significant medical problem in terms of urgency and treatment. Shunting of cerebrospinal fluid has dramatically reduced the morbidity and mortality of hydrocephalus, but they have potential complications that may need multiple surgical procedures during a patient's lifespan. We evaluated the following individual characteristics in relation to shunt complication rates: sex, ethnicity, age at the time of the first shunt placement (1 month [neonate], 1 to 12 months [infant], 1 to 18 years [child], 18 years [adult]), hydrocephalus type (spina bifida, congenital excluding spina bifida, communicating, obstructive) and socioeconomic status. In this retrospective study 193 patients were analyzed, unfortunately 27 where lost in the procedure of follow up and 12 died this patients were excluded from studies. Obstructive hydrocephalus (47.9%) was the most common diagnosis followed by communicating hydrocephalus (13.3%). Patients with ventriculoperitoneal shunt that were followed over time in 37% of cases experienced at least one surgical shunt complication during the study period and 13% of patients had multiple shunt complications. The causes for shunt malfunction include shunt infection, obstruction, distal catheter migration, shunt disconnection etc. Neonates and children experienced the highest complication rates. By 5 years of follow-up almost half of the children required a repeat surgical procedure. Children with obstructive hydrocephalus experienced the greatest risk of needing an initial shunt revision. Ventriculoperitoneal shunts constitute a significant medical problem, in terms of both urgency of treatment and economic costs. In conclusion, young infants are at highest risk for CSF shunt revision.

Successful laparoscopic division of a patent ductus venosus: report of a case

Patent ductus venosus (PDV) is a rare condition of a congenital portosystemic shunt from the umbilical vein to the inferior vena cava. This report presents the case of an adult patient with PDV, who was successfully treated with laparoscopic shunt division. A 69-year-old male was referred with hepatic encephalopathy. Contrast-enhanced CT revealed a large connection between the left portal vein and the inferior vena cava, which was diagnosed as PDV. The safety of a shunt disconnection was confirmed using a temporary balloon occlusion test for the shunt, and the shunt division was performed laparoscopically. The shunt was carefully separated from the liver parenchyma with relative ease, and then divided using a vascular stapler. Portal flow was markedly increased after the operation, and the liver function of the patient improved over the 3-month period after surgery. Although careful interventional evaluation for portal flow is absolutely imperative prior to surgery, a minimally invasive laparoscopic approach can be safely used for treating PDV.

Onyx embolization of high flow spontaneous cervical vertebral arteriovenous fistula

High flow spontaneous vertebral arteriovenous shunts in patients with fibromuscular dysplasia (FMD) are rare. We present a 59-year-old woman with progressive dizziness, pre-syncopal episodes and tinnitus. Catheter-based angiography identified features of FMD and a high flow, right cervical vertebral artery arteriovenous shunt. Onyx-18 embolization (Onyx liquid embolic system, eV3, Irvine, CA, USA) of the principal draining veins was performed with initial detachable coil placement. Complete disconnection of the shunt was achieved without sacrifice of the parent vertebral artery. Thus, spontaneous high flow vertebral arteriovenous shunts can be successfully occluded with Onyx/detachable coil embolization of the principal recipient veins. To our knowledge, this is the first report of Onyx embolization of the recipient veins with shunt disconnection and preservation of the affected vertebral artery in a patient with FMD.

Onyx Embolization of High-Flow Spontaneous Cervical Vertebral Arteriovenous Fistula

High-flow spontaneous vertebral arteriovenous shunts in patients with fibromuscular disease (FMD) are rare. Onyx embolization of the recipient veins with shunt disconnection and preservation of the affected vertebral artery in a patient with FMD has not been reported. A 59-year-old female presented with progressive dizziness, pre-syncopal episodes, and tinnitus. Catheter-based angiography identified features of fibromuscular dysplasia and a high-flow right cervical vertebral artery arteriovenous shunt. Onyx embolization of the principle draining veins was performed with initial detachable coil placement. Complete disconnection of the shunt was achieved without sacrifice of the parent vertebral artery. Spontaneous high-flow vertebral arteriovenous shunts can be successfully occluded with Onyx/detachable coil embolization of the principle recipient veins.

An unusual case of a rare disease pelvic arteriovenous malformation concealing a spinal dural arteriovenous fistula

Dear Editor,Due to the nonspecific nature of clinical symptoms, there isa long delay between onset of first symptoms and definitivediagnosis of SDAVF often. We report the case of a patientwith congestive myelopathy believed to be caused by alarge pelvic arteriovenous malformation, which concealed athoracic SDAVF.Case reportA 62-year-old man presented with progressive myelopathy.T2-weighted MRI of the entire spinal cord revealed a highintramedullary signal from Th7-Th9, accompanied byintradural dilated perimedullary vessels. These finding areconsistent with dural arteriovenous fistulas; therefore,selective spinal angiograms (DSA) were performed. How-ever, two DSAs failed to reveal any SDAVF; but, a largepelvic arteriovenous malformation (pAVM), with feedersfrom the internal iliac arteries and massively dilateddraining veins into the inferior caval vein, was incidentallyfound. Following the assumption that the pAVM waspossibly obstructing the drainage of the spinal veins therebycausing congestive damage to the spinal cord, it wasdecided to perform a partial embolization of the AVMbecause a complete embolization or surgical removal wasbelieved to harm the patient. However, several partialembolizations failed to relieve his symptoms. Thereafter,the patient was referred to our department for re-evaluation.A further spinal DSA failed to detect any SDAVFs.Therefore, we performed a complete embolization of thepAVM followed by surgical shunt disconnection. Hissymptoms regressed.Two months later, his symptoms progressed again. MRIshowed congestive changes of the cord. A pelvic angio-gram showed no revascularization of the pAVM. By then,due to the matching clinical signs and MRI findings, anSDAVF became highly suspicious again. However, aSDAVF was not detected by two complete spinal DSAs.Finally, using a multidetector computed tomographicangiography (MDCTA), at Th3 an arteriovenous fistulawas revealed. The feeder was from the sixth spinal artery,which sprouted from a bronchial artery that originated fromthe thoracic aorta a few millimeters above the seventhspinalartery(Fig.1). Therefore, this bronchial artery was notdetected by spinal angiography because the neuroradiologist,not expecting such an anatomic anomaly, was able tocatheterize the seventh spinal artery, only. The MDCTAfinding was then confirmed by a targeted DSA (Fig. 1).Finally, the fistula was clipped and the patient’ssymptomswere regressive.Six months later, the patient presented again with aprogressive myelopathy. MRI revealed an enlargement ofthe T2-signal intensity of the thoracic spine but without anyperimedullary dilated veins. A MDCTA did not show anysigns of a SDAVF recurrence. CSF and blood laboratoryexams found no evidence for any inflammation or

Acute respiratory failure following shunt disconnection

Background A sixteen year old boy with a Meningomyocele/Arnold Chiari Malformation was admitted to the Emergency Department of a large community regional hospital, with acute respiratory failure. His back defect had been closed shortly after birth and a ventriculoperitoneal (VP) shunt inserted. He had had only one shunt revision, when he was thirteen months old, and he underwent an uneventful scoliosis repair at twelve years of age for a significant scoliosis.

Removal of Ventricular Shunts

Background: Although most patients with an implanted ventriculoperitoneal shunt device will require cerebrospinal fluid diversion over the course of their lifetime, there appears to be a small number of patients that are shunt independent and may benefit from shunt removal. Methods: We retrospectively analyzed 661 patients with hydrocephalus treated over a 10-year period at a single institution. In 10 patients, a systematic shunt weaning protocol was attempted before removal of the cerebrospinal fluid shunt. Results: Ten patients underwent an attempt at shunt removal. Seven of these patients were successfully weaned and 3 were not. The indications to attempt shunt removal for the 7 patients that were successfully weaned were recurrent complications and infections requiring multiple shunt externalizations and revisions in 4 patients, asymptomatic shunt disconnection in 2 patients, and symptomatic overdrainage in 1 patient. None of the patients that were successfully weaned had a history of shunt failure resulting in ventriculomegaly. Two of the 3 patients who failed shunt weaning attempts had a history of shunt failure that resulted in ventriculomegaly. Conclusion: A small number of patients with shunted hydrocephalus may benefit from removal of their shunt.