Surgically managed idiopathic intracranial hypertension in adults

Idiopathic intracranial hypertension

Acta Neurochir (2015) 157:2099–2103

Idiopathic intracranial hypertension (IIH) is a rare condition that is often managed conservatively. In patients with aggressive progression of the disease surgical options are considered. There are few data on the outcomes of these patients when surgically managed. We describe our experience of surgically managed IIH and the outcomes of these patients, in particular the surgical revision rate and interventions required for resolution of symptoms.

Methods A retrospective review of all patient files coded with benign intracranial hypertension, idiopathic intracranial hypertension or pseudotumour cerebri was undertaken. Files were searched with the date of diagnosis and the date these patients were referred for surgical intervention. The surgical interventions and complications were then documented and note was made of the number of inpatient admissions and days spent in hospital.

Results From 2000–2013, 79 patients were identified as patients with IIH that had required surgical intervention; 52 % required further surgical intervention. The average number of surgical interventions was 5.6. For patients requiring further intervention the average number of surgical interventions was 8.6. On average patients with IIH also spent 42 inpatient days in neurosurgical beds, whilst those patients who required further intervention spent 63 days on average in neurosurgical beds. The length of the average individual admission was longer for patients requiring repeated surgical interventions.

Conclusion Based on our experience, patients that require surgical management of IIH frequently require further surgical interventions to control symptoms and manage complications of CSF diversion surgery. Those that require such further intervention on average will have six further operations and spend significantly longer in hospital. Lumboperitoneal (LP) shunting is an effective first line surgical intervention for 52% of our patient cohort. This sub-group of patients therefore requires specialist neurosurgical input for this long-term and challenging pathological process.

Feasibility of radiological markers in idiopathic normal pressure hydrocephalus

Feasibility of radiological markers in idiopathic normal pressure hydrocephalus

Acta Neurochir (2015) 157:1709–1719

Various radiological markers have been proposed for diagnostics in idiopathic normal pressure hydrocephalus (iNPH).We examined the usefulness of radiological markers in the diagnostics and prediction of shunt response in iNPH.

Method In this retrospective cohort study, we evaluated brain CTor MRI scans of 390 patients with suspected iNPH. Based on a 24-h intraventricular pressure monitoring session, patients were classified into a non-NPH (n=161) or probable iNPH (n=229) group. Volumes of cerebrospinal fluid compartments (lateral ventricles, sylvian and suprasylvian subarachnoid spaces and basal cisterns) were visually assessed. Disproportionally enlarged subarachnoid spaces, flow void, white matter changes, medial temporal lobe atrophy and focally dilated sulci were evaluated. Moreover, we measured quantitative markers: Evans’ index (EI), the modified cella media index, mean width of the temporal horns and callosal angle.

Results iNPH was more likely in patients with severe volumetric disproportion between the suprasylvian and sylvian subarachnoid spaces than in those without disproportion (OR 7.5, CI 95 % 4.0–14.1, P<0.0001). Mild disproportion (OR 2.6, CI 95 % 1.4–4.6, P=0.001) and narrow temporal horns (OR per 1mm0.91, CI 95%0.84–0.98, P=0.014)were also associated with an iNPH diagnosis. Other radiological markers had little association with the iNPH diagnosis in the final combined multivariate model. Interestingly, EI was higher in non-NPH than iNPH patients (0.40 vs. 0.38, P= 0.039). Preoperative radiological markers were not associated with shunt response.

Conclusions Visually evaluated disproportion was the most useful radiological marker in iNPH diagnostics. Narrower temporal horns also supported an iNPH diagnosis, possibly since atrophy was more pronounced in the non-NPH than iNPH group.

Single Port Optical Access Laparoscopic Shunt Insertion

Modern Paradigm for Peritoneal Catheter Insertion- Single Port Optical Access Laparoscopic Shunt Insertion
Operative Neurosurgery 11:205–212, 2015

Ventriculoperitoneal shunting is one of the most commonly performed neurosurgical procedures. Typically, for insertion of the peritoneal catheter, a mini-laparotomy technique is used. Although generally safe, it can be cosmetically undesirable and time consuming. Complications include malpositioning, bowel injury, and delayed hernias. Laparoscopic techniques have been advocated to address these issues, but have been slow to gain traction with neurosurgeons.
OBJECTIVE: To describe our experience with single port optical access laparoscopy for placement of ventriculoperitoneal shunts. Our technique simplifies adoption of a laparoscopic technique for neurosurgeons looking to incorporate its benefits.
METHODS: All ventriculoperitoneal shunts placed by the senior author since April 2011 were retrospectively reviewed. Surgical and perioperative complications, length of postoperative stay, and need for revisions were analyzed.
RESULTS: Fifty-six patients were included in the study. There were no cases of peritoneal catheter misplacement. One intraoperative complication occurred early in the series, in which there was an injury to the gallbladder necessitating cholecystectomy. There were 7 cases followed by shunt revision inclusive of the abdomen. In 3 cases, pseudocysts were noted.
CONCLUSION: Single port optical access laparoscopy is a fast and minimally invasive technique that allows direct visualization of the layers of the abdominal wall as they are traversed and visualization of the peritoneal catheter during placement. It uses a small cosmetic incision and obviates the need for postoperative abdominal radiographic studies. The procedure has a modest learning curve, but can be safely used without the assistance of an assist surgeon after the skills are acquired.

Assessment of ETV patency with the 3D-SPACE technique

Assessment of third ventriculostomy patency with the 3D-SPACE technique

J Neurosurg 122:1347–1355, 2015

The goal of this study was to determine the value of the 3D sampling perfection with application-optimized contrasts using different flip-angle evolutions (3D-SPACE) technique in the evaluation of endoscopic third ventriculostomy (ETV) patency.

Methods Twenty-six patients with ETV were examined using 3-T MRI units. Sagittal-plane 3D-SPACE with variant flip-angle mode, 3D T1-weighted (T1W), and 3D heavily T2-weighted (T2W) images were obtained with isotropic voxel sizes. Also, sagittal-axial plane phase-contrast cine (PC)-MR images were obtained. The following findings were evaluated: diameters of stoma and third ventricle, flow-void sign on 3D-SPACE and PC-MR images, integrity of the third ventricle on heavily T2W images, and quantitative PC-MRI parameters of the stoma. Obtained sequences were evaluated singly, in combination with one another, and all together.

Results The mean area, flow, and velocity values measured at the level of stoma in patients with patent stoma were significantly higher than those measured in patients with closed stoma (p < 0.05). There was significant correlation among PC-MRI, 3D-SPACE, and 3D heavily T2W techniques regarding assessment of ETV patency (p < 0.001). The 3D-SPACE technique provided the lowest rate of ambiguous results.

Conclusions The 3D-SPACE technique seems to be the most efficient one for determination of ETV patency. The authors suggest the use of 3D-SPACE as a stand-alone first-line sequence in addition to routine brain MRI protocols in assessing patients with ETV, thereby decreasing scan time and reserving the use of a combination of additional sequences such as PC-MRI and 3D heavily T2W images in suspicious or complex cases.

Long-term Functional Outcomes and Predictors of Shunt-Dependent Hydrocephalus After Treatment of Ruptured Intracranial Aneurysms in the BRAT Trial: Revisiting the Clip vs Coil Debate

Hydrocephalus

Neurosurgery 76:608–615, 2015

Acute hydrocephalus is a well-known sequela of aneurysmal subarachnoid hemorrhage (SAH). Controversy exists about whether open microsurgical methods serve to reduce shunt dependency compared with endovascular techniques.

OBJECTIVE: To determine predictors of shunt-dependent hydrocephalus and functional outcomes after aneurysmal SAH.

METHODS: A total of 471 patients who were part of a prospective, randomized, controlled trial from 2003 to 2007 were retrospectively reviewed. All variables including demographic data, medical history, treatment, imaging, and functional outcomes were included as part of the trial. No additional variables were retrospectively collected.

RESULTS: Ultimately, 147 patients (31.2%) required a ventriculoperitoneal shunt (VPS) in our series. Age, dissecting aneurysm type, ruptured vertebrobasilar aneurysm, Fisher grade, Hunt and Hess grade, admission intraventricular hemorrhage, admission intraparenchymal hemorrhage, blood in the fourth ventricle on admission, perioperative ventriculostomy, and hemicraniectomy were significant risk factors (P < .05) associated with shunt-dependent hydrocephalus on univariate analysis. On multivariate analysis, intraventricular hemorrhage and intraparenchymal hemorrhage were independent risk factors for shunt dependency (P< .05). Clipping vs coiling treatment was not statistically associated with VPS after SAH on both univariate and multivariate analyses. Patients who did not receive a VPS at discharge had higher Glasgow Outcome Scale and Barthel Index scores and were more likely to be functionally independent and to return to work 72 months after surgery (P < .05).

CONCLUSION: There is no difference in shunt dependency after SAH among patients treated by endovascular or microsurgical means. Patients in whom shunt-dependent hydrocephalus does not develop after SAH tend to have improved long-term functional outcomes.

DTI-MRI biomarkers in the search for normal pressure hydrocephalus aetiology

DTI chronic hydro

Neurosurg Rev (2015) 38:239–244

Normal pressure hydrocephalus (NPH) is a clinical syndrome characterized by gait disturbances, urinary incontinence and dementia. Clinical presentation overlaps with Alzheimer disease (AD).Early recognition thus early intervention (shunting) is important for successful treatment, but lack of a diagnostic test with sufficient sensitivity and specificity complicates the diagnosis.

We performed literature search and composed a structured review of imaging biomarkers of NPH. Morphometric studies are not sufficient to diagnose NPH. Hydrocephalus is a common finding in elderly people due to the symmetric brain atrophy and is even more pronounced in patients with AD. The key MRI biomarker seems to be diffusion tensor imaging (DTI). According to recent studies, the DTI analysis of the splenium corporis callosi, posterior limb of internal capsule, hippocampus and fornix combined with measurement of Evans index is a promising MRI biomarker of NPH and could be used for NPH diagnostics and in the differential diagnosis from AD and other dementias.

True aqueductal tumors: a unique entity

True aqueductal tumors-a unique entity

Acta Neurochir (2015) 157:169–177

Pure aqueductal tumors (ATs) differ from pineal region and tectal/tegmental tumors in that they are epicentered within the aqueduct. Nevertheless, these tumors are rarely described as a separate type of tumor, and are often grouped with other lesions located in the same vicinity. The present multicenter study focuses on our experience treating patients with pure ATs.

Methods Data from three large tertiary centers was collected retrospectively, including presenting symptoms, treatment paradigm, surgical approaches, pathology, and outcome.

Results Between 1999 and 2013, 16 patients with AT were diagnosed and treated at the three tertiary centers. Ages at presentation ranged from 5.5 to 57 years. Thirteen patients presented with hydrocephalus-related symptoms, and two were identified incidentally. Thirteen patients underwent an endoscopic third ventriculostomy, and two of these underwent a simultaneous endoscopic biopsy (one grade II ependymoma, one non-specified low-grade glioma). Two others underwent shunt placement. Three patients underwent resection due to tumor progression. Pathologies included glioblastoma multiforme, glioneural tumor, and ependymoma grade II. All non-resected tumors remained stable or grew only minimally.

Conclusions ATs are a rare entities that usually present with obstructive hydrocephalus. Treatment includes primarily cerebrospinal fluid drainage (preferably via an endoscopic third ventriculostomy). Simultaneous endoscopic biopsy may be done in selected cases. Tumor resection should be reserved for growing tumors; the trans-fourth ventricular or transchoroidal approaches are probably safer than other approaches used to reach the tectal region.

Predictors Of Shunt Dependency After Aneurysmal Subarachnoid Hemorrhage

Post-SAH Hydrocephalus
Acta Neurochir (2014) 156:2059–2069

Hydrocephalus (HC) after aneurysmal subarachnoid hemorrhage (aSAH) is a common sequel. Proper selection of patients in need of permanent cerebrospinal fluid (CSF) diversion is, however, not straightforward. The aim of this study was to identify predictors of CSF shunt dependency following aSAH.

Methods: We re-analyzed data acquired from aSAH patients previously enrolled in a prospective, controlled single-center clinical trial in which shunt dependency was not one of the end points. In the present study patients were allocated into two groups: those receiving a shunt (here denoted as shunt dependent) and those not receiving a shunt, based on a clinical decision process. Predictors of shunt dependency were identified by applying uni- and multivariable analysis. We tested a set of predefined possible risk factors based on the results of the clinical trial, including the impact of CSF drainage volume exceeding 1,500 ml during the 1st week after ictus.
Results: Ninety patients were included in the study. Significant predictors of shunt dependency were poor clinical grade at admission [odds ratio (OR) 4.7, 95 % confidence interval (CI) 1.2–18.4], large amounts of subarachnoid blood (OR 3.8, 95 % CI 1.0–14.0), large ventricular size on preoperative cerebral computer tomographic (CT) scans (OR 1.0, 95 % CI 1.0–1.1), and CSF volume drainage exceeding 1,500 ml during the 1st week after the ictus (OR 16.3, 95 % CI 4.0–67.1). Age ≥70 years, larger amounts of intraventricular blood, vertebrobasilar aneurysm, and endovascular treatment tended to increase the likelihood of receiving a shunt. Outcome was not significantly different between shunted and non-shunted patients.
Conclusions: In this cohort of patients with clinical grade aSAH at admission, larger amounts of subarachnoid blood and large ventricular size on preoperative cerebral CT, and CSF drainage in excess of 1,500 ml during the 1st week after the ictus were significant predictors of shunt dependency. Shunt dependency did not hamper outcome.

Shunt complications and opening pressure

External lumbar drain- A pragmatic test for prediction of shunt outcomes in idiopathic normal pressure hydrocephalus

J Neurosurg 121:1257–1263, 2014

This study was undertaken to investigate whether a gradual reduction of the valve setting (opening pressure) decreases the complication rate in patients with idiopathic normal-pressure hydrocephalus (iNPH) treated with a ventriculoperitoneal (VP) shunt.

Methods. In this prospective double-blinded, randomized, controlled, dual-center study, a VP shunt with an adjustable valve was implanted in 68 patients with iNPH, randomized into two groups. In one group (the 20–4 group) the valve setting was initially set to 20 cm H2O and gradually reduced to 4 cm H2O over the course of the 6-month study period. In the other group (the 12 group), the valve was kept at a medium pressure setting of 12 cm H2O during the whole study period. The time to and type of complications (hematoma, infection, and mechanical problems) as well as overdrainage symptoms were recorded. Symptoms, signs, and outcome were assessed by means of the iNPH scale and the NPH grading scale.

Results. Six patients in the 20–4 group (22%) and 7 patients in the 12 group (23%) experienced a shunt complication; 9 had subdural hematomas, 3 mechanical obstructions, and 1 infection (no significant difference between groups). The frequency of overdrainage symptoms was significantly higher for a valve setting ≤ 12 cm H2O compared with a setting > 12 cm H2O. The 20–4 group had a higher improvement rate (88%) than the 12 group (62%) (p = 0.032). There was no significant relationship between complications and body mass index, the use of an antisiphon device, or the use of anticoagulants.

Conclusions. Gradual lowering of the valve setting to a mean of 7 cm H2O led to the same rate of shunt complications and overdrainage symptoms as a fixed valve setting at a mean of 13 cm H2O but was associated with a significantly better outcome.

Comparison of techniques for ventriculoperitoneal shunting in 523 patients with subarachnoid hemorrhage

Hydrocephalus

J Neurosurg 121:904–907, 2014

It is common practice to use a new contralateral bur hole for ventriculoperitoneal shunt (VPS) placement in subarachnoid hemorrhage (SAH) patients with an existing ventriculostomy. At Thomas Jefferson University and Jefferson Hospital for Neuroscience, the authors have primarily used the ventriculostomy site for the VPS. The purpose of this study was to compare the safety of the 2 techniques in patients with SAH.

Methods. The rates of VPS-related hemorrhage, infection, and proximal revision were compared between the 2 techniques in 523 patients undergoing VPS placement (same site in 464 and contralateral site in 59 patients).

Results. The rate of new VPS-related hemorrhage was significantly higher in the contralateral-site group (1.7%) than in the same-site group (0%; p = 0.006). The rate of VPS infection did not differ between the 2 groups (6.4% for same site vs 5.1% for contralateral site; p = 0.7). In multivariate analysis, higher Hunt and Hess grades (p = 0.05) and open versus endovascular treatment (p = 0.04) predicted shunt infection, but the VPS technique was not a predictive factor (p = 0.9). The rate of proximal shunt revision was 6% in the same-site group versus 8.5% in the contralateralsite group (p = 0.4). In multivariate analysis, open surgery was the only factor predicting proximal VPS revision (p = 0.05).

Conclusions. The results of this study suggest that the use of the ventriculostomy site for VPS placement may be feasible and safe and may not add morbidity (infection or need for revision) compared with the use of a fresh contralateral site. This rapid and simple technique also was associated with a lower risk of shunt-related hemorrhage. While both techniques appear to be feasible and safe, a definitive answer to the question of which technique is superior awaits a higher level of medical evidence.

Improvement in social function and health-related quality of life after shunt surgery for idiopathic normal-pressure hydrocephalus

HRQOL in iNPH

J Neurosurg 121:776–784, 2014

Object. To investigate the impact of shunt surgery on the activity, participation, autonomy, and health-related quality of life (HRQOL) of patients with idiopathic normal-pressure hydrocephalus (iNPH) as well as the effect on caregiver burden.

Methods. Thirty-seven patients (median age 70 years, range 50–89 years) with iNPH were evaluated before and 6 months after surgery. Symptoms and signs were assessed by the iNPH scale, activities of daily living (ADL) with the Functional Independence Measure (FIM) and Assessment of Motor and Process Skills (AMPS), autonomy and participation with Impact on Participation and Autonomy (IPA), and caregiver burden with the Caregiver Burden Scale (CBS). HRQOL was evaluated with the EQ-5D (EuroQol Group–5 Dimension health survey).

Results. Twenty-four patients (65%) improved clinically (iNPH scale score) and 31 (86%) improved their HRQOL after surgery, almost to the same level as found in the normal population. The patients became more independent in physical and cognitive activities, and participation and autonomy improved. The caregiver burden was decreased among caregivers to male patients but remained unchanged on the overall group level.

Conclusions. After shunt surgery, patients with iNPH showed improvement in most aspects of social life, they became more independent, and their quality of life returned to nearly normal.

A new look at cerebrospinal fluid circulation

A New Look At CSF Circulation (1)

Fluids and Barriers of the CNS 2014, 11:10

According to the traditional understanding of cerebrosspinal fluid (CSF) physiology, the majority of CSF is produced by the choroid plexus, circulates through the ventricles, the cisterns, and the subarachnoid space to be absorbed into the blood by the arachnoid villi.

This review surveys key developments leading to the traditional concept. Challenging this concept are novel insights utilizing molecular and cellular biology as well as neuroimaging, which indicate that CSF physiology may be much more complex than previously believed. The CSF circulation comprises not only a directed flow of CSF, but in addition a pulsatile to and fro movement throughout the entire brain with local fluid exchange between blood, interstitial fluid, and CSF. Astrocytes, aquaporins, and other membrane transporters are key elements in brain water and CSF homeostasis. A continuous bidirectional fluid exchange at the blood brain barrier produces flow rates, which exceed the choroidal CSF production rate by far. The CSF circulation around blood vessels penetrating from the subarachnoid space into the Virchow Robin spaces provides both a drainage pathway for the clearance of waste molecules from the brain and a site for the interaction of the systemic immune system with that of the brain. Important physiological functions, for example the regeneration of the brain during sleep, may depend on CSF circulation.

Should ventriculoatrial shunting be the procedure of choice for normal-pressure hydrocephalus?

hydrocephalus

J Neurosurg 120:1458–1464, 2014

Ventriculoatrial (VA) shunting is rarely used for patients with normal-pressure hydrocephalus (NPH), likely due to surgeon technical preference and case reports indicating cardiopulmonary complications. However, these complications have typically been limited to adults in whom VA shunts had been placed when they were children. Few studies have directly compared VA shunting to ventriculoperitoneal (VP) shunting in cases of NPH.

Methods. The authors retrospectively analyzed all NPH patients treated by a single surgeon at their center from January 2002 through December 2011. Thirty patients were treated with VA shunts (14 male) and 157 with VP shunts (86 male). The patients’ mean age (± SD) at surgery was 73.7 ± 9.4 years for VA shunting and 76.0 ± 8.2 years for VP shunting; the median durations of follow-up were 42.0 months (IQR 19.2–63.6 months) and 34.2 months (IQR 15.8–67.5), respectively. Statistical analysis was performed using chi-square tests and Wilcoxon rank-sum tests.

Results. Perioperative and postoperative complications for VA and VP shunting cohorts, respectively, included distal revision (2.7% vs 6.6%, p = 0.45), proximal revision (2.7% vs 2.5%, p = 0.97), and postoperative seizure (2.7% vs 1.5%, p = 0.62). Shunt drainage–related subdural hematomas/hygromas developed in 8.1%/27.0% of VA shunt– treated patients versus 6.6%/26.4% of VP shunt–treated patients (p = 0.76/0.98) and were nearly always successfully managed with programmable-valve adjustment. Symptomatic intracerebral hemorrhage (1.5%) and shunt infection (2.0%) were only observed in those who underwent VP shunting. Of note, no cardiovascular complications were observed in any patient, and there were no cases of distal occlusion of the VA shunt.

Conclusions. The authors found no significant differences in complication rates between VA and VP shunting, and VA shunting was not associated with any cardiopulmonary complications. Thus, in the authors’ experience, VA shunting is at least as safe as VP shunting for treating NPH. (http://thejns.org/doi/abs/10.3171/2014.1.JNS131808) Key Words • normal-pressure hydrocephalus • ventriculoatrial shunt • ventriculoperitoneal shunt

Endoscopic Transventricular Transaqueductal Magendie and Luschka Foraminoplasty for Hydrocephalus

Endoscopic foraminoplasty for Hydroc

Neurosurgery 74:426–436, 2014

Routinely, hydrocephalus related to fourth ventricular outlet obstruction (FVOO) has been managed with ventriculoperitoneal (VP) shunting or endoscopic third ventriculostomy (ETV). Few reports on Magendie foraminoplasty exist, and Luschka foraminoplasty has not been described.

OBJECTIVE: To present an alternative technique in the management of FVOO via an endoscopic transventricular transaqueductal Magendie and Luschka foraminoplasty and to discuss the indications, technique, findings, and outcomes.

METHODS: Between 1994 and 2011, all patients who underwent endoscopic Magendie and Luschka foraminoplasty were analyzed.

RESULTS: A total of 33 Magendie (28) and/or Luschka (5) foraminoplasties were performed in 30 patients. Twenty-three were adult and 7 were pediatric patients. The etiology of the FVOO was divided into primary etiologies (congenital membrane in 5 and atresia in 2) and secondary causes (neurocysticercosis in 14 patients, bacterial meningitis in 9). Fifteen (50%) had previously failed procedures. Intraoperative findings that led to Magendie/Luschka foraminoplasty were ETV not feasible to perform, nonpatent basal subarachnoid space, or primary FVOO. Minor postoperative complications were seen in 3 patients. Only 26 patients had long-term follow-up; 17 (65.3%) of these had clinical improvement and did not require further procedures. Nine (34.7%) did not improve. Eight required another procedure (7 shunts, and 1 endoscopic procedure). One patient died.

CONCLUSION: Flexible neuroendoscopic transventricular transforaminal Magendie and Luschka foraminoplasty is feasible and safe. These procedures may prove to be viable alternatives to standard ETV and VP shunt in appropriate patients. Adequate intraoperative assessment of ETV success is necessary to identify patients who will benefit.

Hemorrhagic complications of ventriculostomy: incidence and predictors in patients with intracerebral hemorrhage

Optimal trajectory of endoscopic third ventriculostomy

J Neurosurg 120:931–936, 2014

Ventriculostomy—the placement of an external ventricular drain (EVD)—is a common procedure performed in patients with acute neurological injury. Although generally considered a low-risk intervention, recent studies have cited higher rates of hemorrhagic complications than those previously reported. The authors sought to determine the rate of postventriculostomy hemorrhage in a cohort of patients with intracerebral hemorrhage (ICH) and to identify predictors of hemorrhagic complications of EVD placement.

Methods. Patients with ICH who underwent EVD placement and had both pre- and postprocedural imaging available for analysis were included in this study. Relevant data were prospectively collected for each patient who satisfied inclusion criteria. Variables with a p < 0.20 on univariate analyses were included in a stepwise logistic regression model to identify predictors of postventriculostomy hemorrhage.

Results. Sixty-nine patients were eligible for this analysis. Postventriculostomy hemorrhage occurred in 31.9% of patients. Among all patients with intraparenchymal hemorrhage, the mean hemorrhage volume was 0.66 ± 1.06 cm3. Stratified according to ventricular catheter diameter, patients treated with smaller-diameter catheters had a significantly greater mean hemorrhage volume than patients treated with larger-diameter catheters (0.84 ± 1.2 cm3 vs 0.14 ± 0.12 cm3, p = 0.049). Postventriculostomy hemorrhage was clinically significant in only 1 patient (1.4%). Overall, postventriculostomy hemorrhage was not associated with functional outcome or mortality at either discharge or 90 days. In the multivariate model, an age > 75 years was the only independent predictor of EVD-associated hemorrhage.

Conclusions. Advanced age is predictive of EVD-related hemorrhage in patients with ICH. While postventriculostomy hemorrhage is common, it appears to be of minor clinical significance in the majority of patients.

External lumbar drain: A pragmatic test for prediction of shunt outcomes in idiopathic normal pressure hydrocephalus

External lumbar drain- A pragmatic test for prediction of shunt outcomes in idiopathic normal pressure hydrocephalus

Surg Neurol Int 2014;5:12

The consensus on most reliable supplemental test to predict the shunt responsiveness in patients with idiopathic normal pressure hydrocephalus (iNPH) is lacking. The aim of this study is to discuss the utility of external lumbar drain (ELD) in evaluation of shunt responsiveness for iNPH patients.

Methods: A retrospective review of 66 patients with iNPH was conducted. All patients underwent 4‑day ELD trial. ELD‑positive patients were offered ventriculoperitoneal shunt (VPS) surgery. The primary outcome evaluation parameters were gait and mini mental status examination (MMSE) assessment. The family and patient perception of improvement was accounted for in the outcome evaluation.

Results: There were 38 male and 28 female with mean age of 74 years (range 45-88 years). ELD trial was positive in 86% (57/66) of patients. No major complications were encountered with the ELD trial. A total of 60 patients (57 ELD‑positive, 3 ELD‑negative) underwent VPS insertion. The negative ELD trial (P = 0.006) was associated with poor outcomes following shunt insertion. The positive ELD trial predicted shunt responsiveness in 96% patients (P < 0.0001, OR = 96.2, CI = 11.6-795.3). A receiver operating characteristic (ROC) curve analysis revealed that the ELD trial is reasonably accurate in differentiating shunt responder from non‑responder in iNPH patients (area under curve = 0.8 ± 0.14, P = 0.02, CI = 0.52-1.0). The mean follow‑up period was 12‑months (range 0.3- 3 years). The significant overall improvement after VPS was seen in 92% (55/60). The improvement was sustained in 76% of patients at mean 3‑year follow‑up. The number of comorbid conditions (P = 0.034, OR = 4.15, CI = 1.2-9.04), and a history of cerebrovascular accident (CVA) (P = 0.035, OR = 4.4, CI = 1.9-14.6) were the predictors of poor outcome following shunt surgery.

Conclusion: The positive ELD test predicted shunt responsiveness in 96% of patients. With adequate technique, maximal results with minimal complications can be anticipated. The number of comorbidities, history of CVA and negative ELD test were significantly associated with poor shunt outcomes. Key Words: CSF tap test, external lumbar drain, idiopathic normal pressure hydrocephalus, supplemental test, valve pressure, ventriculoperitoneal shunt

Antibiotic-impregnated shunts: effects in pediatric population

bactiseal2

J Neurosurg Pediatrics 13:101–106, 2014

Infection after both primary and revision shunt surgeries remains a major problem in pediatric neurosurgical practice. Antibiotic-impregnated shunt (AIS) tubing has been proposed to reduce infection rates. The authors report their experience with AIS catheters in their large pediatric neurosurgery department.

Methods. The authors conducted a retrospective case review of consecutive shunt operations performed before (1993–2003) and after (2005–2009) introduction of AIS tubing, with analysis of shunt infection rates and causative organisms identified.

Results. The historical control group consisted of 1592 consecutive shunt operations (657 primary insertions), and the AIS study group consisted of 500 consecutive shunt operations (184 primary insertions). Patients ranged in age from 0–17 years. In the historical group, 135 infections were identified (8.4%). In the AIS study group, 25 infections were identified (5%), representing a significant reduction (p < 0.005). The latency to diagnosis of infection was 23 days in the historical group and 139 days in the AIS study group. The infection rates in infants 0–6 months of age were 12.2% (historical group) and 6.7% (AIS group, p < 0.005), and in infants 7–12 months of age the rates were 7.9% (historical group) and 2.7% (AIS group, p < 0.005). In the historical control group, the frequency rank order of causative organisms was coagulase-negative staphylococcus (51.9%), Staphylococcus aureus (31.6%), streptococcus or enterococcus spp. (8.8%), gram-negative organisms (4.4%), and Propionibacterium acnes (2.2%). Organisms responsible for infections in AIS were S. aureus (40%), followed by streptococcus or enterococcus spp. (20%), P. acnes and coagulase-negative staphylococcus (both 16%), and gram-negative organisms (4%). No unusually antibioticresistant bacteria were identified in either group. The authors further subdivided the AIS group into those undergoing primary AIS insertion (Subgroup 1), those undergoing revision of non-AIS systems using AIS components (Subgroup 2), and those undergoing revision of AIS systems using AIS components (Subgroup 3). Infection rates were 1.6% in Subgroup 1, 2.5% in Subgroup 2, and 11.7% in Subgroup 3. Staphylococcus aureus was the most common organism identified in infections of the Subgroups 2 and 3.

Conclusions. Use of AIS tubing significantly improves shunt infection rates in both general pediatric and infant populations with no evidence of increased antibiotic resistance, which is in agreement with previous studies. However, the increased infection rate in revision surgery in children with AIS catheters in situ raises questions about their long-term application.

Ventriculoperitoneal Shunt 30-Day Failure Rate

Gravity assisted vs. medium pressure valves for communicating hydrocephalus show similar valve-revision rates

Neurosurgery 74:29–34, 2014

With the need for transparency of surgical results, 30-day outcome measures have become increasingly important. Ventriculoperitoneal (VP) shunt failure is a substantial burden to patients and health care systems.

OBJECTIVE: This study introduces the 30-day VP shunt failure rate as a possible barometer of surgical outcome and demonstrates its use in a national (United Kingdom [UK]) study and makes comparison with 2 published randomized, controlled trials (RCT).

METHODS: A cohort study of all (except 1) pediatric neurosurgical centers in the UK and Ireland. All new and revision VP shunt operations were recorded for 2008 and 2009. Both newly placed and revised VP shunts were subject to Kaplan-Meier analysis, and 30-day failure rate was obtained. Data from 2 RCTs investigating new VP shunt technology were analyzed, and the 30-day failure rate was extracted for comparative purposes.

RESULTS: The overall 30-day and 1-year failure rates for new shunts were 12.9% and 28.8%, respectively. The 30-day failure rate from 2 RCTs was comparable (14% and 16%, respectively). The failure rate of the subsequent revision of those new shunts was 20.7% at 30 days and 40.4% at 1 year. According to these data, shunt survival appears to be better if performed by a consultant pediatric neurosurgeon for revision surgery only.

CONCLUSION: VP shunt survival in the UK is comparable to the published multicenter data investigating shunt survival. The 30-day failure rate may represent a better barometer of surgical outcome and should be used as a separate outcome measure in the design of future trials.

The callosal angle measured on MRI as a predictor of outcome in idiopathic normal-pressure hydrocephalus

The callosal angle measured on MRI as a predictor of outcome in idiopathic normal-pressure hydrocephalus

J Neurosurg 120:178–184, 2014

Different neuroimaging biomarkers have been studied to find a tool for prediction of response to CSF shunting in idiopathic normal-pressure hydrocephalus (iNPH). The callosal angle (CA) has been described as useful in discriminating iNPH from ventricular dilation secondary to atrophy. However, the usefulness of the CA as a prognostic tool for the selection of shunt candidates among patients with iNPH is unclear. The aim of this study was to compare the CA in shunt responders with that in nonresponders and clarify whether the CA can serve as a predictor of the outcome.

Methods. Preoperative MRI brain scans were evaluated in 109 patients who had undergone shunt surgery for iNPH during 2006–2010. Multiplanar reconstruction was performed interactively to obtain a coronal image through the posterior commissure, perpendicular to the anterior-posterior commissure plane. The CA was measured as the angle between the lateral ventricles on the coronal image. The patients were examined clinically before surgery and at 12 months postoperatively.

Results. Shunt responders had a significantly smaller mean preoperative CA compared with nonresponders: 59° (95% CI 56°–63°) versus 68° (95% CI 61°–75°) (p < 0.05). A CA cutoff value of 63° showed the best prognostic accuracy.

Conclusions. The preoperative CA is smaller in patients whose condition improves after shunt surgery and may be a useful tool in the selection of shunt candidates among patients with iNPH.

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Endoscopic third ventriculostomy: can we predict success during surgery?

ETV-1

Neurosurg Rev (2014) 37:89–97

Endoscopic third ventriculostomy (ETV) is widely used as an alternative technique for hydrocephalus treatment. ETV success or failure may be influenced by numerous factors. In this study, we have analyzed preoperative and intraoperative risk factors and suggest an intraoperative scale to predict etV failure.

Fifty-one patients (27 adults and 24 children) underwent an etV at Carlos Haya University Hospital, Malaga. Intraoperative video records were assessed and the following intraoperative findings were recorded: (1) abnormal ventricular anatomy, (2) intraoperative incident, (3) Liliequist membrane opening in a second endoscopic maneuver, (4) thickened or scarred membranes in the subarachnoid space, (5) absence or “weakness” of pulsation of third ventricle floor at etV completion, and (6) floppy premammillary membrane that needs edge coagulation. An intraoperative scale ranging from 0 to 6 points was performed.

A significant relation was found between a higher result on the prognosis scale and etV failure (p <0.0001). An absence or weakness of pulsation of the third ventricle floor at etV completion was significantly related to etV failure (p <0.0001).

The presence of thickened or scarred membranes in the subarachnoid space was significantly related to etV failure (p <0.04) as well as the Liliequist membrane opening in a second endoscopic maneuver (p <0.008). Intraoperative factors should be taken into account for prediction of etV success. More studies with larger case series are needed to determine the influence of all intraoperative factors over etV success