Neuroendoscopic stent placement for cerebrospinal fluid pathway obstructions in adults.

OBJECTIVE Since its revival in the early 1990s, neuroendoscopy has become an integral component of modern neurosurgery. Endoscopic stent placement for treatment of CSF pathway obstruction is a rarely used and underestimated procedure. The authors present the first series of neuroendoscopic intracranial stenting for CSF pathway obstruction in adults with associated results and complications spanning a long-term follow-up of 20 years. METHODS The authors retrospectively reviewed a prospectively maintained clinical database for endoscopic stent placement performed in adults between 1993 and 2013. RESULTS Of 526 endoscopic intraventricular procedures, stents were placed for treatment of CSF disorders in 25 cases (4.8%). The technique was used in the management of arachnoid cysts (ACs; n = 8), tumor-related CSF disorders (n = 13), and hydrocephalus due to stenosis of the foramen of Monro (n = 2) or aqueduct (n = 2). The mean follow-up was 87.1 months. No deaths or infections occurred that were related to endoscopic placement of intracranial stents. Late stent dislocation or migration was observed in 3 patients (12%). CONCLUSIONS Endoscopic intracranial stent placement in adults is rarely required but is a safe and helpful technique in select cases. It is indicated when reliable and long-lasting restoration of CSF pathway obstructions cannot be achieved with standard endoscopic techniques. In the treatment of tumor-related hydrocephalus, it is a good option to avoid reclosure of the restored CSF pathway by tumor growth. Currently, routine stent placement after endoscopic fenestration of ACs is not recommended. Stent placement for treatment of CSF disorders due to tumor is a good option for avoiding CSF shunting. To avoid stent migration and dislocation, and to allow for easy removal if needed, the device should be fixed to a bur hole reservoir.

Predictors of subsequent overdrainage and clinical outcomes after ventriculoperitoneal shunting for idiopathic normal pressure hydrocephalus.

BACKGROUND: Little is known about variables associated with overdrainage complications and neurofunctional and health-related quality of life outcomes in idiopathic normal-pressure hydrocephalus (iNPH) patients after shunt surgery. OBJECTIVE: To identify candidate demographic and disease-specific predictors of overdrainage and patient-related outcomes, allowing for more personalized care of patients with iNPH. METHODS: This was a secondary analysis of the dataset of the SVASONA study, a multicenter randomized trial comparing gravitational and conventional gravitational valves for treating iNPH. We evaluated the association between baseline items and the incidence of overdrainage, using different endpoint definitions. RESULTS: We identified only a few variables associated with a possible increased risk of overdrainage. Apart from using conventional rather than gravitational valves, longer duration of surgery and female sex were associated with a higher risk of clinical signs and symptoms suggestive of overdrainage (hazard ratio: 1.02, 95% confidence interval: 1.01-1.04 and 1.84, 95% confidence interval: 0.81-4.16). The occurrence of clinical symptoms of overdrainage, and the need for exchanging a programmable by a gravitational valve may adversely affect disease-specific outcomes like the Kiefer score. CONCLUSION: Few, if any, baseline and treatment characteristics may be helpful in estimating the individual risk of complications and clinical outcomes after shunt surgery for iNPH. Patients should be informed that longer surgery for any reason may increase the risk of later overdrainage. Also, women should be counseled about a sex-associated increased risk of the development of clinical symptoms of overdrainage, although the latter cannot be distinguished from a generally higher prevalence of headaches in the female population.

Safety and efficacy of gravitational shunt valves in patients with idiopathic normal pressure hydrocephalus: a pragmatic, randomised, open label, multicentre trial (SVASONA).

OBJECTIVES: To investigate whether gravitational valves reduce the risk of overdrainage complications compared with programmable valves in ventriculoperitoneal (VP) shunt surgery for idiopathic normal pressure hydrocephalus (iNPH). BACKGROUND: Patients with iNPH may benefit from VP shunting but are prone to overdrainage complications during posture changes. Gravitational valves with tantalum balls are considered to reduce the risk of overdrainage but their clinical effectiveness is unclear. METHODS: We conducted a pragmatic, randomised, multicentre trial comparing gravitational with non-gravitational programmable valves in patients with iNPH eligible for VP shunting. The primary endpoint was any clinical or radiological sign (headache, nausea, vomiting, subdural effusion or slit ventricle) of overdrainage 6 months after randomisation. We also assessed disease specific instruments (Black and Kiefer Scale) and Physical and Mental Component Scores of the Short Form 12 (SF-12) generic health questionnaire. RESULTS: We enrolled 145 patients (mean (SD) age 71.9 (6.9) years), 137 of whom were available for endpoint analysis. After 6 months, 29 patients in the standard and five patients in the gravitational shunt group developed overdrainage (risk difference -36%, 95% CI -49% to -23%; p<0.001). This difference exceeded predetermined stopping rules and resulted in premature discontinuation of patient recruitment. Disease specific outcome scales did not differ between the groups although there was a significant advantage of the gravitational device in the SF-12 Mental Component Scores at the 6 and 12 month visits. CONCLUSIONS: Implanting a gravitational rather than another type of valve will avoid one additional overdrainage complication in about every third patient undergoing VP shunting for iNPH.

Endoscopic aqueductoplasty and stenting.

OBJECTIVE: This paper discusses indications for and the technique of endoscopic aqueductoplasty with stenting. METHODS: We review and summarize the clinical experience with endoscopic aqueductoplasty gained over the last 15 years on pediatric and adult patients. RESULTS: Endoscopic aqueductoplasty with stenting presents a safe procedure. In well selected patients, it provides a long-term, stable clinical course. Aqueductoplasty alone has a high reclosure rate and should be avoided. CONCLUSIONS: Aqueductoplasty with stenting is the procedure of choice for the treatment of isolated fourth ventricle. Membranous and tumor-related aqueductal stenosis should be treated by endoscopic third ventriculostomy.

Experiences with a gravity-assisted valve in hydrocephalic children. Clinical article.

OBJECT: Over the past decade, a gravity-assisted valve (GAV) has become a standard device in many European pediatric hydrocephalus centers. Because past comparative clinical outcome studies on valve design have not included any GAV, the authors in this trial evaluated the early results of GAV applications in a pediatric population. METHODS: For a minimum of 2 years the authors monitored 169 of 182 hydrocephalic children who received a pediatric GAV at their first CSF shunt insertion (61.5%) or as a substitute for any differential pressure valve (38.5%) at 1 of 7 European pediatric hydrocephalus centers. Outcomes were categorized as valve survival (primary outcome) or shunt survival (secondary outcome). The end point was defined as valve explantation. RESULTS: Within a follow-up period of 2 years, the valve remained functional in 130 (76.9%) of 169 patients. One hundred eight of these patients (63.9%) had an uncomplicated clinical course without any subsequent surgery, and 22 (13%) were submitted to a valve-preserving catheter revision without any further complications during the follow-up period. Thirty-nine patients (23.1%) reached an end point of valve explantation: 13 valve failures from infection (7.7%), 8 (4.7%) from overdrainage, and 18 (10.6%) from underdrainage. CONCLUSIONS: Compared with nongravitational shunt designs, a GAV does not substantially affect the early complication rate. Valve-preserving shunt revisions do not increase the risk of subsequent valve failure and therefore should not be defined as an end point in studies on valve design. A significant impact of any well-established valve design on the early complication rate in shunt surgery is not supported by any current data; therefore, this correlation should be dismissed. As overdrainage-related complications have been shown to occur late, the presumed advantages of a pediatric GAV remain to be shown in a long-term study.

Primary diffuse leptomeningeal gliomatosis in a 2-year-old girl.

BACKGROUND: Primary diffuse leptomeningeal gliomatosis is a rare tumor disease affecting the leptomeninx of the CNS. It is thought to originate from subarachnoidal glial cell nests. The symptoms are often rather unspecific. Surgery is not an option and despite the use of chemotherapy and radiotherapy patients rarely survive for more than 12 months. CASE DESCRIPTION: We present a case of PDLG in a 2-year-old girl, the youngest patient reported on so far. She presented with increasing somnolence, intermittent strabism, and vomiting. Magnetic resonance imaging of the cranium showed enlarged ventricles and contrast enhancement of the basal leptomeninx. Cerebrospinal fluid diagnostic studies showed a mild pleocytosis and elevated protein levels but no tumor cells or evidence of infection. A ventriculoperitoneal shunt was placed and a biopsy of the leptomeninx was taken in the right Sylvian fissure. The histopathology findings suggested a nonspecific meningeal inflammation. Because the girl developed spinal symptoms with paresthesia and hyperalgesia, a spinal MRI was performed which showed a similar contrast enhancement of the spinal leptomeninx. A spinal biopsy was taken and subsequently a paucicellular astrocytic tumor was diagnosed corresponding to a WHO I diffuse leptomeningeal gliomatosis. Chemotherapy with vincristine, carboplatin, and etoposide was initiated (Protocol SIOP-LGG 2004) but was stopped by the parents when the child was in partial remission after 50 weeks because of a neurologic deterioration. The girl has so far survived for more than 29 months. CONCLUSION: Primary diffuse leptomeningeal gliomatosis must be included in the differential diagnosis of diffuse leptomeningeal contrast enhancement in young children. There are promising treatment options that need to be carefully evaluated.

Posterior fossa tumors in children: how long does it take to establish the diagnosis?

OBJECTIVE: The aim of this study is to evaluate, for our patient population, the time interval from the first chart-documented symptom to the radiological diagnosis in children and infants with posterior fossa tumors. MATERIALS AND METHODS: We retrospectively analyzed 50 consecutive children (36 men, 14 women) with posterior fossa tumor treated at our department between January 1999 and December 2003. The mean age at time of diagnosis was 98 months (6 months-16 years). The mean follow up was 27 months (6-61 months). The diagnoses included astrocytoma (n = 17), medulloblastoma (n = 15), ependymoma (n = 6), and other tumors (n = 12). RESULTS: The mean time interval between onset of symptoms and radiographic diagnosis was 142 days (5-535 days), the median was 59 days. The mean time for Grade I and II tumors was 238 days (n = 19) and for tumors Grade III and IV 117 days (n = 31). The most common presenting symptoms were headache, nausea, vomiting, ataxia, and oculomotor deficits. Approximately half of the patients were initially diagnosed and treated for other diseases (gastrointestinal infection, appendicitis, psychological behavioral problems, cervical spine strains, different ophthalmologic entities). Specialists (ophthalmologists, orthopedics) tended to diagnose and treat their specific diagnoses (e.g., strabism, torticollis). Parents play a significant role in the process of establishing the correct diagnosis. CONCLUSION: We conclude that further information and education regarding symptomatology and diagnosis of posterior fossa tumors in children is necessary. Communication has to be improved between parents and referring physicians of all specialties and neurosurgeons.

Diagnosis and management of cerebral salt wasting (CSW) in children: the role of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP).

OBJECTIVE: The aim of this study is to report our experience with diagnosis and management of cerebral salt wasting (CSW) in children and to evaluate the role of atrial natriuretic peptide/brain natriuretic peptide (ANP/BNP) in pediatric patients. MATERIALS AND METHODS: We present nine children suffering from prevalent cerebral disease--seven of whom underwent anesthesia and surgical procedures--with features of CSW, seen within a 22-month period. The symptoms, patient characteristics (including hormone status), monitoring, treatment protocol, and outcome are described. RESULTS: Natriuresis (urine Na+ concentrations 131 to >250 mmol/l) and polyuria (5.5+/-1.5 ml/kg/h) with increased Na+ turnover (maximum Na+ loss: median 1.50 mmol Na+/kg/h, range 0.47 to >3.50) vanished within 2 weeks in 6/9 patients (increase in serum Na+ from 127+/-2 mmol/l to 136+/-1). K+ excretion was also high (maximum K+ loss: median 0.18 mmol K+/kg/h, range 0.09-0.53). ANP/BNP as suspected causes of salt wasting were elevated only in 1/6 and 2/7 patients, respectively. Plasma renin activities and aldosterone levels were either suppressed or in the low normal range. CONCLUSION: Natriuresis and polyuria are the main diagnostic criteria for CSW. The fluid balance in CSW is negative, in contrast to a positive fluid balance in SIADH. The length of the disease is self-limited and generally ceases within 2 weeks, while Na+, K+, and fluid turnover should be monitored carefully. Only a minority of our children showed elevated ANP/BNP levels. A dose/effect relationship for natriuretic peptide levels and increased Na+ turnover could not be established.

Hydrocephalus in children with posterior fossa tumors: role of endoscopic third ventriculostomy.

OBJECT: Controversy exists regarding the indication for endoscopic third ventriculostomy (ETV) in children with hydrocephalus caused by posterior fossa tumors. The authors present their treatment modalities and discuss the role of ETV in the management of hydrocephalus. METHODS: The authors retrospectively reviewed the cases of 58 children who were admitted to their clinic consecutively with posterior fossa tumors between January 1999 and December 2003. Fifty-two patients presented with hydrocephalus. The mean age at the time of admission was 6 years and 3 months. The mean follow-up period was 25 months. The authors evaluated how many children required a cerebrospinal fluid (CSF) draining procedure (external ventricular drain [EVD], ventriculoperitoneal [VP] shunt, or ETV) prior to or following tumor removal. Only six patients (11.5%) required permanent treatment for hydrocephalus. Four patients received a VP shunt and two patients underwent ETV. A temporary EVD was placed in five patients (two required a shunt). Forty-six patients (88.5%) did not require a permanent CSF draining procedure. CONCLUSIONS: For children with posterior fossa tumors, ETV is not indicated as a standard operation either prior to or following tumor removal. Only six of 52 children presenting with hydrocephalus required a permanent CSF draining procedure. Endoscopic third ventriculostomy may be suitable for patients with fourth ventricle outflow obstruction and persisting or progressive hydrocephalus following tumor removal.

Endoscopic third ventriculostomy in infants.

OBJECT: The failure rate following endoscopic third ventriculostomy (ETV) in infants younger than 1 year of age has been reported to be higher compared with that of older children. The authors present results of ETVs in such infants and advocate that success or failure of the procedure depends not on the age of the patient but on the cause of the hydrocephalus. METHODS: The authors retrospectively reviewed the management and outcome of 18 ETVs in infants for the treatment of hydrocephalus. The surgeries were performed between November 1996 and October 2002. The mean age at the time of surgery was 150 days (range 9-354 days). The minimal follow-up period was 18 months and the mean was 50 months. The authors divided the patients into the following three groups: obstructive hydrocephalus (four infants), communicating hydrocephalus (10 infants), and hydrocephalus associated with myelomeningocele (four infants). No perioperative death occurred, and perioperative transient morbidity related to ETV was low. The success of the procedure was determined by the cause of the hydrocephalus. Infants with obstructive hydrocephalus had a 100% success rate (four of four), and infants with communicating hydrocephalus had a 10% success rate (one of 10). In infants with hydrocephalus related to myelomeningocele, the success rate was 50% (two of four). CONCLUSIONS: The authors conclude that ETV presents an effective alternative for the treatment of obstructive hydrocephalus in infants younger than 1 year of age. Age does not present a contraindication for ETV, nor does it increase the perioperative risk. The success of ETV is determined by the cause of the hydrocephalus.

Management of tectal glioma in childhood.

Tectal glioma is a topographical diagnosis including tumors of different histology, mainly low-grade astrocytomas. Clinical symptoms are usually associated with increased intracranial pressure. This report discusses the management of this rare tumor in children. Clinical charts of 12 children with tectal glioma treated in our department between 1976 and 2001 were retrospectively reviewed. The mean age at the time of diagnosis was 6.75 years (range, 4 weeks to 16 years). The duration between first symptoms and the diagnosis of tectal glioma was in the range of 2 days to 9 years. Ten patients presented with symptoms associated with increased intracranial pressure, one patient presented with ataxia, and in one case tectal glioma was an incidental finding. First-line therapy was endoscopic third ventriculostomy in 5 cases (42%), ventriculoperitoneal shunting in 6 cases (50%), and combined partial tumor resection and shunting in one case. Histology was obtained in 5 cases (low-grade astrocytoma, n = 4; ependymoma, n = 1). All patients had good neurologic function at the end of follow-up. Tectal glioma represents a distinct subgroup of brainstem tumors associated with a good (or favorable) prognosis. Effective treatment for hydrocephalus is essential; the tumor should be monitored by regular clinical examination and magnetic resonance imaging. Biopsy is warranted in cases with tumor progression.

Endoscopic aqueductoplasty and interventriculostomy for the treatment of isolated fourth ventricle in children.

OBJECTIVE: There are different approaches for the treatment of isolated fourth ventricle in children, including a suboccipital ventriculoperitoneal shunt, suboccipital craniotomy with microsurgical fenestration, and endoscopic fenestration. We discuss the indications, surgical methods, and outcome of 18 patients who underwent endoscopic treatment for isolated fourth ventricle. METHODS: We retrospectively reviewed the medical histories of 18 patients with an isolated fourth ventricle. Surgical procedures included endoscopic aqueductoplasty, endoscopic aqueductoplasty with a stent, endoscopic interventriculostomy (lateral ventricle or third ventricle to fourth ventricle), and endoscopic interventriculostomy with a stent. Operations were performed between July 1997 and June 2002. The mean age of the patients at the time of surgery was 3 years. The mean follow-up was 29 months. All patients had a supratentorial ventriculoperitoneal shunt. RESULTS: Clinical symptoms (impairment of consciousness, tetraparesis, and ataxia) improved in all patients. Reduction of the size of the fourth ventricle was observed in all patients. Seven patients required reoperation because of restenosis (39% revision rate). Restenosis occurred between 2 weeks and 7 months after surgery (average, 3 mo). Four patients underwent reoperation with stent placement, and three patients underwent reaqueductoplasty. We had the following complications: one infection, one asymptomatic subdural hygroma, one transient oculomotor paresis, and one permanent oculomotor paresis (4 [22%] of 18 patients). CONCLUSION: The significant failure rate of fourth ventricle shunts has led to the development of alternative treatment methods. Endoscopic aqueductoplasty or interventriculostomy presents an effective, minimally invasive, and safe procedure for the treatment of isolated fourth ventricle in pediatric patients. Compared with suboccipital craniotomy and microsurgical fenestration, endoscopic aqueductoplasty is less invasive, and compared with fourth ventricle shunts, it is more reliable and effective.

Endoscopic aqueductoplasty: stent or not to stent?

OBJECTIVE: The aim of this study is to evaluate if the long-term interventricular communication following aqueductoplasty is determined by the etiology of the aqueductal stenosis (AS). METHODS: We retrospectively analyzed 27 patients who underwent endoscopic aqueductoplasty or endoscopic interventriculostomy with or without a stent for the treatment of AS or isolated fourth ventricle. Surgeries were performed between July 1997 and June 2003. Mean age at the time of surgery was 8 years. Mean follow-up is 24 months. RESULTS: We divided the patients into three groups. Group 1 consisted of 5 patients with membranous distal AS. Four patients were sufficiently treated by aqueductoplasty alone and 1 asymptomatic restenosis occurred. Group 2 consisted of 4 patients with AS due to a periaqueductal tumor. Three patients underwent aqueductoplasty and tumor biopsy with subsequent restenosis of the aqueduct. One patient underwent aqueductoplasty with a stent and tumor biopsy at the same time. Group 3 consisted of 18 patients with isolated fourth ventricle. The initial surgery was successful in 11 patients. Seven patients required revisions. CONCLUSION: The long-term communication following aqueductoplasty is determined by the etiology and morphology of the AS. In patients with a membranous distal AS aqueductoplasty alone will suffice. In patients with tumor-associated AS aqueductoplasty alone will not stay open. Those patients would better be treated with third ventriculostomy. In patients with isolated fourth ventricle the risk of restenosis is high. Therefore, we favor primary stent placement.

Cerebral edema leading to decompressive craniectomy: an assessment of the preceding clinical and neuromonitoring trends.

The aim of this study was to examine the pre-operative clinical and neuromonitoring courses in patients with a decompressive craniectomy to assess and to compare clinical and neuromonitoring signs indicating extensive cerebral edema. We conducted a retrospective analysis of the clinical signs and courses of simultaneous monitoring of intracranial pressure (ICP) and cerebral oxygenation (PtiO2) in 26 consecutive patients who were sedated and treated with a decompressive craniectomy due to extensive cerebral edema after aneurysmal subarachnoid hemorrhage (SAH) (n = 20) or severe head injury (SHI) (n = 6). Pathological monitoring trends always preceded clinical deterioration. In 18 of 26 patients extensive cerebral edema was indicated solely by increasing ICP > 20 mmHg or decreasing PtiO2 < 10 mmHg or both. Anisocoria occurred in only 8 of 26 patients. As opposed to SHI patients, 9 of 20 SAH patients showed decreasing PtiO2 as first warning sign clearly before neurological deterioration or ICP increase. This series shows the utility of combined ICP and PtiO2 monitoring in patients who develop extensive cerebral edema. Pathological monitoring trends indicate deterioration prior to clinical signs which offers a wider therapeutical window. PtiO2 monitoring appears to be particularly valuable after aneurysmal SAH as adjunct to ICP monitoring and CT imaging.

Endoscopic intraventricular surgery for treatment of hydrocephalus and loculated CSF space in children less than one year of age.

Controversy exists regarding whether children under 1 year of age have a higher risk of treatment failure after neuroendoscopic procedures for the treatment of hydrocephalus than older children. We retrospectively reviewed the surgical management and clinical outcome of 15 infants who underwent neuroendoscopic surgery for the treatment of CSF space loculation and hydrocephalus. We performed 8 third ventriculostomies, 3 endoscopic arachnoid cyst fenestrations, 2 aqueductoplasties, 1 septostomy and in 1 patient, three endoscopic fenestrations for isolated ventricular compartments. Two of the third ventriculostomies, 1 of the aqueductoplasties and the 1 septostomy failed, and these patients underwent placement of a ventriculoperitoneal shunt. In all other patients, symptoms and signs related to hydrocephalus or CSF space loculation were relieved effectively after the endoscopic procedure. We conclude that neuroendoscopy presents an effective alternative for the treatment of hydrocephalus and CSF loculation in infants less than 1 year of age.