Search

External ventricular drain (EVD) and lumbar drain insertion are 2 of the most commonly performed neurosurgical procedures worldwide for acute hydrocephalus. Mechanical complications, such as obstruction or cerebrospinal fluid (CSF) leakage, are often seen and may contribute toward significant patient morbidity. Different CSF drainage methods are advocated to reduce the incidence of complications, but evidence regarding comparative effectiveness is limited.In this single-center prospective cohort study, the incidence of mechanical complications and associated interventional factors, including choice of drain, collecting system, and location, were studied in patients requiring CSF diversion for acute hydrocephalus. Univariate analyses were performed to explore trends within the data, followed by a repeated-measures mixed-effects regression to determine the independent influence of drain device on mechanical failure.Sixty-one patients required CSF diversion between January 2020 and March 2021, via 3 different drain types (lumbar drain, tunneled, and bolted EVD) and 2 collection systems (LiquoGuard 7 and AccuDrain), performed in either theater or intensive care. Twenty-one patients (39%) experienced a mechanical complication, with blockage being the most common. Multivariate analyses showed that bolted EVDs (odds ratio, 0.08; confidence interval, 0.01-0.58) and LiquoGuards (OR, 0.23; CI, 0.08-0.69) were significantly associated with fewer mechanical complications compared with tunneled EVDs and gravity-based collection systems, respectively (P ≤ 0.01).Drain device has an influence on the occurrence of EVD-related complications. These preliminary findings suggest that choosing bolted EVDs and motor-assisted drainage can reduce drain-associated mechanical failure. A randomized controlled trial comparing drain devices is required to confirm these findings.

External ventricular drainage (EVD) is one of the most commonly performed neurosurgical procedures. Despite this, the optimal drainage and weaning strategies are still unknown. This PRISMA-compliant systematic review and meta-analysis analysed the outcomes of patients undergoing EVD procedures, comparing continuous versus intermittent drainage and rapid versus gradual weaning. Four databases were searched from inception to 01/10/2020. Articles reporting at least 10 patients treated for hydrocephalus secondary to subarachnoid haemorrhage were included. Other inclusion criteria were the description of the EVD drainage and weaning strategies used and a comparison of continuous versus intermittent drainage or rapid versus gradual weaning within the study. Random effect meta-analyses were used to compare functional outcomes, incidence of complications and hospital length of stay. Intermittent external CSF drainage was associated with lower incidence of EVD-related infections (RR = 0.20, 95% CI 0.05–0.72, I-squared = 0%) and EVD blockages compared to continuous CSF drainage (RR = 0.45, 95% CI 0.27–0.74, I-squared = 0%). There was no clear advantage in using gradual EVD weaning strategies compared to rapid EVD weaning; however, patients who underwent rapid EVD weaning had a shorter hospital length of stay (SMD = 0.34, 95% CI 0.22–0.47, I-squared = 0%). Intermittent external CSF drainage after SAH is associated with lower incidence of EVD-related infections and EVD blockages compared to continuous CSF drainage. Patients who underwent rapid EVD weaning had a shorter hospital length of stay and there was no clear clinical advantage in using gradual weaning.

In the last 6 years, following the first pathological description of presumed amyloid-beta (Aβ) transmission in humans (in 2015) and subsequent experimental confirmation (in 2018), clinical cases of iatrogenic cerebral amyloid angiopathy (CAA)—attributed to the transmission of Aβ seeds—have been increasingly recognised and reported. This newly described form of CAA is associated with early disease onset (typically in the third to fifth decade), and often presents with intracerebral haemorrhage, but also seizures and cognitive impairment. Although assumed to be rare, it is important that clinicians remain vigilant for potential cases, particularly as the optimal management, prognosis, true incidence and public health implications remain unknown. This review summarises our current understanding of the clinical spectrum of iatrogenic CAA and provides a diagnostic framework for clinicians. We provide clinical details for three patients with pathological evidence of iatrogenic CAA and present a summary of the published cases to date (n=20), identified following a systematic review. Our aims are: (1) To describe the clinical features of iatrogenic CAA, highlighting important similarities and differences between iatrogenic and sporadic CAA; and (2) To discuss potential approaches for investigation and diagnosis, including suggested diagnostic criteria for iatrogenic CAA.

The insertion of bolt external ventricular drains (EVD) on the intensive care unit (ICU) has enabled rapid cranial cerebrospinal fluid (CSF) diversion. However, bolt EVDs tend to be perceived as a more challenging technique, particularly when dealing with small ventricles or when there is midline shift distorting the ventricular morphology. Furthermore, if neuronavigation guidance is felt to be necessary, this usually assumes a transfer to an operating theatre. In this technical note, we describe the use of electromagnetic neuronavigation for bolt EVD insertion on the ICU and assess the protocol’s feasibility and accuracy. Case series of neuronavigation-assisted bolt EVD insertion in ICU setting, using Medtronic Flat Emitter for StealthStation EM. Neuronavigation-guided bolt EVDs were placed at the bedside in n = 5 patients on ICU. Their widest frontal ventricular horn diameter in the coronal plane ranged from 11 to 20 mm. No procedural complications were encountered. Post-procedural CT confirmed the optimal placement of the EVDs. Electromagnetic neuronavigation is feasible at the ICU bedside and can assist the insertion of bolt EVDs in this setting. The preference for a bolt EVD to be inserted in ICU—as is standard practice at this unit—should not prohibit patients from benefitting from image guidance if required.

Compared with endovascular techniques, clipping of ruptured cerebral aneurysms has been shown to associate with increased morbidity in several studies. Despite this, clipping remains the preferred option for many aneurysms. The objective of this study is to describe the reported adverse events of open repair of ruptured cerebral aneurysms and their impact on patient outcome. The PubMed, Embase and Cochrane databases were searched between June 1999 and June 2019 to identify original studies of at least 100 patients undergoing surgical repair of ruptured cerebral aneurysms and in which adverse event rates were reported. Thirty-six studies reporting adverse events in a total of 12,410 operations for repair of ruptured cerebral aneurysms were included. Surgical adverse events were common with 36 event types reported including intraoperative rupture (median rate of 16.6%), arterial injury (median rate of 3.8%) and brain swelling (median rate 5.6%). Only 6 surgical events were statistically shown to associate with poor outcomes by any author and for intraoperative rupture (the most frequently analysed), there was an even split between authors finding a statistical association with poor outcome and those finding no association. Even with modern surgical techniques, the technical demands of surgical aneurysm repair continue to lead to a high rate of intraoperative adverse events. Despite this, it is not known which of these intraoperative events are the most important contributors to the poor outcomes often seen in these patients. More research directed towards identifying the events that most drive operative morbidity has the potential to improve outcomes for these patients. Electronic supplementary material The online version of this article (10.1007/s10143-020-01312-4) contains supplementary material, which is available to authorized users.

Background The hydrodynamics of cerebrospinal fluid shunts have been described in vitro; however, knowledge on the response of intracranial pressure (ICP) to valve settings adjustments in vivo is limited. This study describes the effect of adjusting the shunt valve setting on ICP in a cohort of patients with complex symptom management. Method Single-centre retrospective observational study. Patients who underwent ICP-guided valve setting adjustments during 24-h continuous ICP monitoring, between 2014 and 2019, were included. Patients with suspected shunt malfunction were excluded. Median night ICP before and after the valve adjustments were compared (Δ night ICP). The responses of ICP to valve adjustment were divided into 3 different groups as follows: expected, paradoxical and no response. The frequency of the paradoxical response and its potential predicting factors were investigated. Results Fifty-one patients (37 females, 14 males, mean age 38 years) receiving 94 valve setting adjustments met the study inclusion criteria. Patients’ underlying conditions were most commonly hydrocephalus (47%) or idiopathic intracranial hypertension (43%). The response of ICP to valve setting adjustments was classified as ‘expected’ in 54 cases (57%), ‘paradoxical’ in 17 cases (18%) and ‘no effect’ (Δ night ICP p = 0.01 and Medtronic Strata, p = 0.02). Conclusions Paradoxical ICP changes can occur after shunt valve setting adjustments. This observation should be taken into account when performing ICP-guided valve adjustments and is highly relevant for the future development of “smart” shunt systems.

Background Given recent positive safety evidence, ventriculoatrial (VA) shunt placement may increase in popularity once more. We describe a rare case of Tricuspid regurgitation due to VA shunt catheter tip traversing the valve. Case Description A woman aged 42 years with a preexisting VA shunt was referred to this center with 3 months of orthostatic headache, nausea, and palpitations that occurred while sleeping on her right side. An echocardiogram demonstrates a VA shunt catheter in the right atrium during cardiac diastole, which traversed the tricuspid annular plane during cardiac systole. The echocardiogram revealed mild to moderate tricuspid regurgitation. She had no clinical evidence of cardiac failure or arrhythmia and had normal electrocardiogram findings. The catheter tip appeared to be adhered to the underside of the leaflets or to the chordae tendineae. Pulling the catheter tip back could therefore cause irreversible damage to the tricuspid valve. For this reason, the catheter was not removed, and the patient was referred for close follow-up with cardiologists. A literature review was performed to determine where this rare complication fits into the spectrum of VA shunt distal catheter complications, and what techniques can be done to avoid similar occurrences. Conclusions This report reiterates the importance of ensuring the tip is carefully placed within the atrium, under fluoroscopic guidance. Although rare, the described complication is difficult to manage once it has occurred.

Slit ventricles can be a challenging target during shunt catheter insertion. Traditionally, the frontal approach has been considered optimal for small ventricles. At this center, routine use of electromagnetic (EM) stereotactic guidance (Stealth, Medtronic, Dublin, Ireland) has enabled a parietooccipital (P-O) burr hole approach to the frontal horns. We compare shunt placement and revisions required for patients with slit ventricles who had shunts inserted via a P-O approach versus frontal shunt.We studied a retrospective cohort of patients with slit ventricles and a ventricular shunt inserted using EM guidance between 2012 and 2018. Slitlike ventricles were defined as the widest point of the lateral ventricle3 mm. Outcome measures included placement accuracy and survival using the Kaplan-Meier curve. Optimal final catheter tip location was considered to be the frontal horn of the ipsilateral lateral ventricle.Eighty-two patients (77 female, 5 male) aged 34.9 ± 10.8 years (mean ± standard deviation) had ventricular shunts inserted for idiopathic intracranial hypertension (n = 63), chiari/syrinx (n = 8), congenital (n = 10), and pseudomeningocele (n = 1). Of those identified, 35 had primary P-O shunts and 46 had frontal shunts. Overall, 94% of cases had the catheter tip sitting in the frontal horn. The P-O approach was just as accurate as the frontal approach. Eight P-O shunts and 9 frontal shunts required revision over a 60-month period. There was no significant different in shunt survival between the 2 approaches (P = 0.37).EM-guided placement has enabled the P-O approach to be as safe and with equivalent survival to frontal approach. The accuracy of shunt placement between the 2 approaches was similar.

Pharmacological prophylaxis of venous thromboembolism (VTE) requires nuanced decision-making to balance the risk of VTE against haemorrhage. This problem is compounded in neurosurgical patients, in whom postoperative intracranial haemorrhage (ICH) may be catastrophic, compared to non-neuraxial bleeding in other types of surgery. Current major guidelines recommend caution when using pharmacological prophylaxis in elective cranial surgery, but incorporate low-quality evidence and lack precise guidance on timing and duration of anticoagulation.We aimed to answer the following questions for patients undergoing elective cranial surgery: (1) when is the optimal time to initiate postoperative anticoagulation, and (2) how long should postoperative anticoagulation be continued for? In this systematic review, we screened randomised and non-randomised studies reporting original data on pharmacological VTE prophylaxis in elective cranial surgery. Outcomes of interest were VTE and ICH.Three retrospective, single-centre observational studies met eligibility criteria, with a total of 923 participants. Meta-analysis was not performed due to a high risk of bias across all studies. Through narrative synthesis, we found that patients who developed VTE were significantly more likely to receive their first postoperative dose at a later time (mean: 144 vs. 29 h,The limited evidence favours earlier initiation and shorter courses of thromboprophylactic anticoagulation. These findings are specific to patients undergoing surgery for meningioma or glioma and may not apply to other populations. Randomised controlled trials or robustly designed observational studies are necessary to establish a clearer evidence base.

After craniectomy, patients are generally advised to wear a helmet when mobilising to protect the unshielded brain from damage. However, there exists limited guidance regarding head protection for patients at rest and when being transferred or turned. Here, we emphasise the need for such protocols and utilise evidence from several sources to affirm our viewpoint. A literature search was first performed using MEDLINE and EMBASE, looking for published material relating to head protection for patients post-craniectomy during rest, transfer or turning. No articles were identified using a wide-ranging search strategy. Next, we surveyed and interviewed staff and patients from our neurosurgical centre to ascertain how often their craniectomy site was exposed to external pressure and the precautions taken to prevent this. 59% of patients admitted resting in contact with the craniectomy site, in agreement with the observations of 67% of staff. In 63% of these patients, this occurred on a daily basis and for some, was associated with symptoms suggestive of raised intracranial pressure. 44% of staff did not use a method to prevent craniectomy site contact while 65% utilised no additional precautions during transfer or turning. 63% of patients received no information about avoiding craniectomy site contact upon discharge, and almost all surveyed wished for resting head protection if it were available. We argue that pragmatic guidelines are needed and that our results support this perspective. As such, we offer a simple, practical protocol which can be adopted and iteratively improved as further evidence becomes available in this area.

For the diagnosis of subarachnoid haemorrhage (SAH), the presence of cerebrospinal fluid (CSF) xanthochromia is still considered the gold standard for patients with a thunderclap headache, in the absence of blood on brain CT scan. However, a traumatic lumbar puncture (LP) typically results in high concentrations of oxyhaemoglobin in CSF, impairing the detection of xanthochromia and preventing the reliable exclusion of SAH. In this context, the value of a repeat lumbar puncture has not yet been described.A retrospective case series of suspected SAH patients, with a negative CT scan and initial traumatic LP, managed with a repeat LP to assess for CSF xanthochromia. Clinical notes, laboratory and imaging results were reviewed.Between August 2011 and January 2020, 31 patients with suspected SAH were referred to our neurosurgical unit following negative CT and traumatic LP. A repeat LP was performed in 7 of the 31 patients, 2.4 days (±0.79 SD) after the first traumatic LP. CSF spectrophotometry analysis from repeated LP in all 7 patients was negative for xanthochromia. No adverse clinical events were recorded on average 18 months following discharge.A repeat LP performed following a traumatic tap can still yield xanthochromia-negative CSF, thereby, excluding SAH, avoiding unnecessary invasive angiography and overall promoting the safer management of these patients.

The accuracy of tunneled external ventricular drain (EVD) placement has been shown to be similar among practitioners of varying experience, but this has not yet been investigated for bolt EVDs. Tunneled and bolt EVDs are distinct techniques, and it is unclear if conclusions regarding accuracy can be inferred from one method to the other. The goal of this study was to determine whether neurosurgical experience influences the accuracy of bolt EVD placement. We performed a single-center retrospective analysis of accuracy of bolt EVD placement between 1st December 2018 and 31st May 2020, comparing the accuracy outcomes between three levels of training (junior trainees (JT); mid-grade trainees (MT); senior trainees/fellows (ST)). Accuracy was determined radiologically by two methods: Kakarla grade and by measuring the distance of the catheter tip to its optimal position (DTOP) at the foramen of Monro. Eighty-seven patients underwent insertion of bolt EVDs, of which n = 19 by JT, n = 40 by MT and n = 28 by ST, with a significant difference found between training grades in the median Kakarla grade (p = 0.0055) and in the accuracy of placement as per DTOP (p = 0.0168). In contrast to previous published results on tunneled EVDs, we demonstrate that the accuracy of bolt EVD placement is dependent on neurosurgical experience. Our results draw awareness to the fact that the bolt EVD technique can represent a challenge for less experienced practitioners and underline the importance of dedicated training to support the safe insertion of bolt ventricular catheters.

Background Multimodal monitoring of intracranial pressure and brain tissue oxygen tension (PbtO2) have been increasingly used to detect delayed cerebral ischemia (DCI) after subarachnoid hemorrhage. At our center, patients who cannot be easily assessed clinically will undergo intracranial pressure and PbtO2 monitoring via a NEUROVENT-PTO bolt. We aimed to determine whether the Lindegaard ratios (LRs) computed from transcranial Doppler ultrasonography (TCDU) would correlate with, or can predict, the simultaneously recorded PbtO2 value. Methods Patients with aneurysmal subarachnoid hemorrhage, PbtO2 recordings from the middle cerebral artery territory, and simultaneous TCDU scans available from the ipsilateral middle cerebral artery and internal carotid artery from August 2018 to 2019 were included in the present study. The index test result was vasospasm (LR of ≥3) found on TCDU. The reference standard was the presence of regional hypoxia (PbtO2 Results A total of 28 patients (6 men and 22 women; age, 59.04 ± 13.75 years) were identified with simultaneous brain tissue oxygen and TCDU recordings available. Of the 28 patients, 7 had cerebral hypoxia (PbtO2 Conclusion We find TCDU to be specific for predicting cerebral hypoxia (measured via an intraparenchymal probe). Therefore, it could be a useful and noninvasive tool in the context of preventative DCI monitoring. However, given the low sensitivity, the lack of vasospasm on TCDU should not preclude the possibility of the presence of evolving DCI.

Objective Ventriculoperitoneal (VP) shunt surgery is a common and effective treatment for hydrocephalus and cerebrospinal fluid disorders. Infection remains a major cause of morbidity and mortality after a VP shunt. There is evidence that a deep skin flora microbiome may have a role to play in post-operative infections. In this technical note, we present a skin preparation technique that addresses the issue of the skin flora beyond the initial incision. Methods The patient is initially prepped, as standard, with. a single layer of 2% CHG+70% isopropyl alcohol. The novel stage is the 'double incision' whereby an initial superficial incision receives a further application of povidone-iodine prior to completing the full depth incision. Results Of the 84 shunts inserted using the double-incision method (September 2015 to September 2016), only one developed a shunt infection. Conclusion The double incision approach to skin preparation is a unique operative stage in VP shunt surgery that may have a role to play in reducing acute shunt infection.

Tinnitus is a symptom commonly associated with idiopathic intracranial hypertension (IIH) that can have a profound effect on quality of life. We aim to determine tinnitus symptom response after dural venous sinus stenting (DVSS) or CSF diversion with a shunt, in patients with both pulsatile (PT) and non-pulsatile tinnitus (NPT). Single-centre cohort of IIH patients (2006–2016) who underwent 24-h ICP monitoring (ICPM). An un-paired t test compared ICP and pulse amplitude (PA) values in IIH patients with PT vs. NPT. We identified 59 patients with IIH (56 F:3 M), mean age 32.5 ± 9.49 years, 14 of whom suffered from tinnitus. Of these 14, seven reported PT and seven reported NPT. Patients with tinnitus had a mean 24-h ICP and PA of 9.09 ± 5.25 mmHg and 6.05 ± 1.07 mmHg respectively. All 7 patients with PT showed symptom improvement or resolution after DVSS (n = 4), secondary DVSS (n = 2) or shunting (n = 1). In contrast, of the 7 with NPT, only 1 improved post intervention (DVSS), despite 2 patients having shunts and 5 having DVSS. NPT and PT were equally as common in our group of IIH patients. DVSS appears to be an effective management option for IIH patients with a clear history of pulsatile tinnitus. However, non-pulsatile tinnitus was more persistent and did not respond well to either DVSS or CSF diversion.

Background Complex hydrocephalus affecting lateral and fourth ventricles separately is occasionally managed with cerebrospinal fluid diversion via supratentorial and infratentorial ventricular catheters. The optimal configuration to reduce complications is currently unknown in adults. We describe a consistently similar clinical presentation of patients with complex hydrocephalus and a fourth ventricle separately drained by infratentorial shunt insertion. Methods This was a retrospective single-center case series. Medical notes were reviewed for clinical presentation, brain imaging, and neurophysiologic tests results. All patients underwent intracranial pressure monitoring (ICPM). Outcomes were determined by ventricular appearance on brain imaging computed tomography and symptomatic improvements postoperatively. Results Five adult patients referred to the hydrocephalus service had separate infratentorial and supratentorial shunt systems. A common clinical presentation was observed, including lower motor neuron facial palsy (confirmed with electrophysiology), ophthalmoplegia, dysarthria, impaired gait headache, and nausea. We refer to this as transtentorial distortion syndrome. Twenty-four-hour ICPM demonstrated clear low pressures. All patients underwent shunt revision connecting the transtentorial shunts via a Y-connector and the addition of a distal valve. All subjects had improved ventricular appearance on computed tomography scans post revision, and normalization of ICPM was observed. In the follow-up period of 6 months, no patient required further shunt revision. Conclusion To prevent transtentorial distortion syndrome, supratentorial and infratentorial shunt constructs in adults with encysted fourth ventricles should be similar to the shunt systems widely known in the pediatric population with Dandy-Walker syndrome (i.e., joint output to a single valve distal to the connection of the 2 proximal drainage catheters).

Background Idiopathic normal pressure hydrocephalus (INPH) has no reliable biomarker to assist in the selection of patients who could benefit from ventriculo-peritoneal (VP) shunt insertion. The neurodegenerative markers T-tau and Aβ1-42 have been found to successfully differentiate between Alzheimer’s disease (AD) and INPH and therefore are candidate biomarkers for prognosis and shunt response in INPH. The aim of this study was to test the predictive value of cerebrospinal fluid (CSF) T-tau and Aβ1-42 for shunt responsiveness. In particular, we pay attention to the subset of INPH patients with raised T-tau, who are often expected to be poor surgical candidates. Methods Single-centre retrospective analysis of probable INPH patients with CSF samples collected from 2006 to 2016. Index test: CSF levels of T-tau and Aβ1-42. Reference standard: postoperative outcome. ROC analysis assessed the predictive value. Results A total of 144 CSF samples from INPH patients were analysed. Lumbar T-tau was a good predictor of post-operative mobility (AUROC 0.80). The majority of patients with a co-existing neurodegenerative disease responded well, including those with high T-tau levels. Conclusion INPH patients tended to exhibit low levels of CSF T-tau, and this can be a good predictor outcome. However levels are highly variable between individuals. Raised T-tau and being shunt-responsive are not mutually exclusive, and such patients ought not necessarily be excluded from having a VP shunt. A combined panel of markers may be a more specific method for aiding selection of patients for VP shunt insertion. This is the most comprehensive presentation of CSF samples from INPH patients to date, thus providing further reference values to the current literature.

Cerebral aneurysms in complex anatomical locations and intraoperative rupture of aneurysms are challenging for neurosurgeons and anaesthetists alike. Mechanical and non-mechanical methods to reduce blood flow into aneurysms are well-recognised techniques to facilitate aneurysm exclusion from the circulation. Mechanical methods like temporary clipping of parent arteries, carotid artery ligation and endovascular balloon occlusion are commonly used in clinical practice. However, non-mechanical techniques such as rapid ventricular pacing and adenosine-induced cardiac standstill with hypotension are still emerging strategies. The aim of this study is to report our units’ experience in the use of adenosine in aneurysm clipping and arteriovenous malformation (AVM) resection and review the literature. The records of all patients who had adenosine-assisted clipping of intracranial aneurysms and AVM resections in our institute between November 2015 and December 2016 were extracted from prospectively maintained database. The following data were collected: patient demographics, comorbidities, size and location of the aneurysms or AVM, number of boluses and total dose of adenosine administered, duration of cardiac standstill and hypotension (systolic blood pressure

To improve quality of care for patients presenting with chronic subdural haematoma (CSDH) by introducing a multi-disciplinary integrated care pathway.CSDH is a common neurological condition. Incidence rises with age and currently affects around 58/100 000 people over 70 years. Six-month mortality is high (26%), however integrated care pathways have been shown to improve patient outcomes in other surgical subspecialties.A baseline retrospective audit completed in 2012 identified areas for improvement in patient management. Stakeholder meetings were held with subsequent development and implementation of a patient care pathway. A post-implementation prospective audit was completed between January and October 2015.patient demographics, medical co-morbidities, use of anti-platelet and anti-coagulant medication, timing of surgery, length of hospital stay, morbidity and mortality data, and reaccumulation rate.Patient groups were similar with a high incidence of multi-morbidity. The key areas targeted for improvement included enhanced pre-operative optimisation and time to surgery. Implementation of the patient care pathway significantly increased the number of patients undergoing surgery within 24 hours of admission (43% vs. 75%, p = 0.0006) but length of hospital stay did not change. Operative morbidity and mortality remained similar and there was no significant difference in CSDH reaccumulation rate.Our patient care pathway appears to have improved pre-operative care and significantly increased the proportion of patients undergoing surgery within 24 hours of admission. Difficulties were encountered with changing existing practice. Prospective research is required to demonstrate the full benefits, which may include a reduction in health and social care costs.

The ever present need to balance over drainage with under drainage in hydrocephalus has required innovations including adjustable valves with antigravity devices. These are activated in the vertical position to prevent siphoning. We describe a group of bedridden patients who presented with unexplained under drainage caused by activation of antigravity shunt components produced by peculiar head/body position. Retrospective single centre case series of hydrocephalus patients, treated with ventriculo-peritoneal (VP) shunt insertion between April 2014 - February 2016. These patients presented with clinical and radiological under drainage syndrome. Medical notes were reviewed for clinical picture and outcome. Radiological studies were reviewed assessing shunt placement and ventricular size. Seven patients presented with clinical and radiological under drainage syndrome. A consistent posturing of long term hyper-flexion of the neck whilst lying supine was observed. All patients had similar shunt construct (adjustable Miethke ProGAV valve and shunt assistant anti-gravity component). In each of those patients a hypothesis was formulated that neck flexion was activating the shunt assistance anti-gravity component in supine position. Five patients underwent shunt revision surgery removing the shunt assistant device from the cranium and adding an anti-gravity component to the shunt system at the chest. One had the shunt assistant completely removed and one patient was managed conservatively with mobilisation. All patients had clinical and radiological improvement. Antigravity shunt components implanted cranially in bedridden hydrocephalus patients will produce underdrainage due to head flexion induced anti-gravity device activation. In these patients, anti-gravity devices should be placed at the chest. Alternatively, special nursing attention should be paid to head-trunk angle.

Raised white cell count (WCC) in lumbar CSF is a commonly used marker of meningitis. The effect of cranial neurosurgery per se on lumbar WCC is not established. At this single centre, many patients undergo ICPM followed by lumboperitoneal shunt (LPS), with lumbar CSF WCC samples taken during insertion. We aimed to determine the effect of ICP bolt insertion on lumbar CSF WCC. We undertook a retrospective analysis of lumbar CSF samples in patients who had recently undergone 24-h ICPM. Thirty-three patients (16F:7M) aged 43.31 ± 12.1 years (mean ± SD) had lumbar CSF samples after ICPM. Fourteen had CSF sampled within 6 weeks and 19 after 6 weeks of ICPM. Twenty-five samples were taken during LPS insertion, 5 during lumbar drainage/puncture and 3 during LPS revision. All 33 patients were afebrile at the point of CSF sampling. The mean lumbar WCC within 6 weeks of ICPM was significantly higher than the mean lumbar WCC after 6 weeks, being 15.4 ± 18.0 and 2.32 ± 1.79 cells/microlitre respectively respectively. There was no significant increase in RBC. In patients with raised CSF WCC, 60% of raised WCC were predominantly lymphoctyes and 40% predominantly neutrophils. Only one patient grew an organism (S. aureus). We conclude that lumbar CSF WCC can be raised following minor intracranial surgery, despite no clinical sign of infection. We caution against using lumbar CSF WCC values independently as the only marker of infection following neurosurgery.

Background Patients with normal pressure hydrocephalus (NPH) are often elderly, frail and affected by multimorbidity. Treatment is surgical with cerebrospinal diversion shunts. The selection of patients that are of an acceptable level of risk to be treated surgically has been a matter of debate for years and has deprived some patients of life-changing surgery. The aim of this service evaluation was to investigate the preoperative risk factors and early postoperative morbidity of patients with NPH using a standardized postoperative survey. Materials and methods Consecutive NPH patients admitted for neurosurgical management of NPH between May 2017 and May 2018 were included in this prospective service evaluation. In addition to the collection of traditional outcome measures, the cardiac version of the Postoperative Morbidity Survey (C-POMS) was conducted on postoperative days 4, 7, and 10 to identify postoperative morbidity. Results Eighty-eight patients (63 males, age mean±SD, 75±7 y) underwent 106 surgical procedures (61 lumbar drains, 45 ventriculoperitoneal shunts). There was no 30-day mortality and no unexpected return to the operating room or admission to intensive care unit. There was 1 conservatively managed surgical complication. On postoperative day 4, the C-POMS identified no postoperative morbidity in 72% of the patients, and mild morbidity (postoperative nausea and mobility issues) in 28%. There was a delay in discharge in 50% of the patients with no postoperative morbidity on day 4, highlighting areas of our service requiring improvement. Conclusions Early postoperative outcomes of NPH patients are good after both ventriculoperitoneal shunt insertion and lumbar drainage. This evaluation provides initial evidence on the utility of the C-POMS as a service evaluation tool in the standardized assessment postoperative outcomes in neurosurgery patients.

Purpose of review This article describes the physiology of cerebrospinal fluid (CSF). We review current evidence and new concepts relating to CSF physiology with respect to CSF secretion, circulation and resorption and we highlight key pathophysiological associations including the relationship between CSF and intracranial pressure. Recent findings CSF secretion occurs primarily via the choroid plexus. Various transport mechanisms facilitate CSF secretion but the role Aquaporins play in this process is a recent discovery and an area of ongoing research. CSF circulation is a dynamic process but the importance of the perivascular 'Glymphatic system' and extraarachnoidal pathways of resorption are relatively new concepts. Summary CSF physiology is dependent on various interacting factors and is critical for normal brain development and function.

Selecting probable idiopathic normal pressure hydrocephalus (INPH) patients for shunt insertion presents a challenge because of coexisting comorbidities and other conditions that could mimic NPH. The characteristic appearance of DESH (Disproportionately Enlarged Subarachnoid Space Hydrocephalus) on brain imaging has been shown to have a high positive predictive value in identifying shunt responsive INPH patients (SINPHONI trial). However, the negative predictive value of this radiological sign was not clearly demonstrated. The aim of the present study was to calculate the negative predictive value of the DESH sign.A single centre study of probable INPH patients, who underwent ventriculoperitoneal (VP) shunt insertion. Shunt responsive INPH patients were identified as those having improvement in their walking speed, neuropsychological assessment and continence one year post operatively. Preoperative images were reviewed for DESH sign. Negative and Positive Predictive Values (NPV and PPV) of DESH sign were determined post analysis.A total of 103 probable INPH patients were included (31 were DESH positive (30%) and 72 were DESH negative (70%)). A total of 78 patients showed measurable improvement one year post shunt insertion (76%); 24 (31%) of these patients were DESH positive and 54 (69%) were DESH negative (p=0.001). Therefore, the DESH sign had an estimated PPV of 77% and NPV of 25%.DESH sign demonstrates a low negative predictive value. We conclude that DESH negative patients should still undergo prognostic tests for iNPH, such as an extended lumbar drainage protocol, and should not be excluded from shunt insertion.

Cerebrospinal fluid (CSF) leak following spinal surgery is a relatively common surgical complication. A disturbance in the underlying CSF dynamics could be the causative factor in a small group of patients with refractory CSF leaks that require multiple surgical repairs and prolonged hospital admission. A retrospective case series of patients with persistent post spinal surgery CSF leak referred to the hydrocephalus service for continuous intracranial pressure (ICP) monitoring. Patients’ notes were reviewed for medical history, ICP data, radiological data, and subsequent management and outcome. Five patients (two males/three females, mean age, 35.4 years) were referred for ICP monitoring over a 12-month period. These patients had prolonged CSF leak despite multiple repair attempts 252 ± 454 days (mean ± SD). On ICP monitoring, all five patients had abnormal results, with the mean ICP 8.95 ± 4.41 mmHg. Four had abnormal pulse amplitudes, mean 6.15 mmHg ± 1.22 mmHg. All five patients underwent an intervention. Three patients underwent insertion of ventriculoperitoneal (VP) shunts. One patient had venous sinus stent insertion and one patient underwent medical management with acetazolamide. All five of the patients’ CSF leak resolved post intervention. The mean time to resolution of CSF leak post intervention was 10.8 ± 12.9 days. Abnormal cerebrospinal fluid dynamics could be the underlying factor in patients with a persistent and treatment-refractory CSF leak post spinal surgery. Treatments aimed at lowering ICP may be beneficial in this group of patients. Whether abnormal pressure and dynamics represent a pre-existing abnormality or is induced by spinal surgery should be a subject of further study.

The diagnosis of ventricular shunt lumen obstruction remains a challenging area. Common methods of assessment are often invasive, while routine imaging techniques are unhelpful in diagnosing shunt obstruction in cases where ventricular size remains unaffected. Constructive Interference in Steady State (CISS) is a 3D gradient echo MRI sequence that accentuates T2 values between cerebrospinal fluid (CSF) and surrounding structures. This clinical image demonstrates the use of CISS MRI, for the first time, to non-invasively demonstrate proximal shunt lumen obstruction in three patients presenting with suspected shunt catheter obstruction.

To compare multidisciplinary team (MDT) decision making at our centre with the suggested management from the recently published Unruptured Intracranial Aneurysm Treatment Score (UIATS), with particular focus on disagreements between the two bodies of expert opinion.A retrospective audit of local practice.Adult patients with incidental cerebral saccular aneurysms referred to The National Hospital for Neurology and Neurosurgery Neurovascular MDT.Review of MDT records from 2010-2015 and collection of UIATS criteria. MDT decisions for each aneurysm were designated as conservative or treatment group, then assessed for correlation with the UIATS.Data was collected on 398 aneurysms from 296 patients. 57% of aneurysms were managed conservatively and 43% were treated with endovascular or open repair. Total follow up was 8409 aneurysm months (mean: 21 months per aneurysm). The overall proportion of agreement (p0) was 66.6% (95% CI: 61.9-71.2). Cohen's Kappa (k) was 0.325 suggesting only a "fair" level of agreement between the two raters. Absolute agreement rates increased from 60% in 2010 to 74% in 2015. Aneurysm size was an important factor for disagreement, 77% of aneurysms treated following MDT, but not in agreement with the UIATS, were7 mm, compared with only 70.5% in those treated following MDT and in agreement with UIATS.There was disagreement between the two expert opinions analysed in this study. A key factor was aneurysm size, with decision making at our centre seemingly more guided by older landmark papers such as work by the International Study of Unruptured Intracranial Aneurysms (ISUIA) group. However, agreement was at its highest at the end of the study period, suggesting increasing convergence between the two bodies of expert opinion. The reasons for disagreement and particularly clinicians' reliance on aneurysm size in decision making is something that needs consideration when planning and auditing aneurysm services.

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. 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. 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. 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.

OBJECTIVEIdiopathic intracranial hypertension (IIH) is commonly associated with venous sinus stenosis. In recent years, transvenous dural venous sinus stent (DVSS) insertion has emerged as a potential therapy for resistant cases. However, there remains considerable uncertainty over the safety and efficacy of this procedure, in particular the incidence of intraprocedural and delayed complications and in the longevity of sinus patency, pressure gradient obliteration, and therapeutic clinical outcome. The aim of this study was to determine clinical, radiological, and manometric outcomes at 3–4 months after DVSS in this treated IIH cohort.METHODSClinical, radiographic, and manometric data before and 3–4 months after DVSS were reviewed in this single-center case series. All venographic and manometric procedures were performed under local anesthesia with the patient supine.RESULTSForty-one patients underwent DVSS venography/manometry within 120 days. Sinus pressure reduction of between 11 and 15 mm Hg was achieved 3–4 months after DVSS compared with pre-stent baseline, regardless of whether the procedure was primary or secondary (after shunt surgery). Radiographic obliteration of anatomical stenosis correlating with reduction in pressure gradients was observed. The complication rate after DVSS was 4.9% and stent survival was 87.8% at 120 days. At least 20% of patients developed restenosis following DVSS and only 63.3% demonstrated an improvement or resolution of papilledema.CONCLUSIONSReduced venous sinus pressures were observed at 120 days after the procedure. DVSS showed lower complication rates than shunts, but the clinical outcome data were less convincing. To definitively compare the outcomes between DVSS and shunts in IIH, a randomized prospective study is needed.

Elective intraparenchymal intracranial pressure (ICP) monitoring is useful for the diagnosis and treatment of hydrocephalus and cerebrospinal fluid (CSF) disorders. This retrospective study analyzes median ICP and pulse amplitude (PA) recordings in neurosurgically naive patients undergoing elective ICP monitoring for suspected CSF disorders. Retrospective review of prospectively collated database of neurosurgically naive patients undergoing elective ICP monitoring for suspected hydrocephalus and CSF disorders. Following extraction of the median ICP and PA values (separated into all, day and night time recordings), principal component analysis (PCA) was performed to identify the principal factors determining the spread of the data. Exploratory comparisons and correlations of ICP and PA values were explored, including by post hoc diagnostic groupings and age. A total of 198 patients were identified in six distinct diagnostic groups (n = 21–47 in each). The PCA suggested that there were two main factors accounting for the spread in the data, with 61.4% of the variance determined largely by the PA and 33.0% by the ICP recordings. Exploratory comparisons of PA and ICP between the diagnostic groups showed significant differences between the groups. Specifically, significant differences were observed in PA between a group managed conservatively and the Chiari/syrinx, IIH, and NPH/LOVA groups and in the ICP between the conservatively managed group and high-pressure, IIH, and low-pressure groups. Correlations between ICP and PA revealed some interesting trends in the different diagnostic groups and correlations between ICP, PA, and age revealed a decreasing ICP and increasing PA with age. This study provides insights into hydrodynamic disturbances in different diagnostic groups of patients with CSF hydrodynamic disorders. It highlights the utility of analyzing both median PA and ICP recordings, stratified into day and night time recordings.

Introduction. Idiopathic normal pressure hydrocephalus (iNPH) is a shunt- reversible syndrome of the elderly. Shunt management is aimed at achieving a balance between clinical improvement and the complications associated with overdrainage. Although clinical improvement occurs at low pressure, these benefits may be negated by the increase in complication rates observed at lower pressures. The addition of gravity-switch devices has been shown to reduce over drainage problems even at a low valve pressure setting. At our centre the Miethke proGAV is used and commonly lowered below 5 cmH2O to gain further clinical improvement. Object. To determine whether lowering the opening pressure to below 5cmH2O using the proGAV valve in iNPH patients results in a) improved clinical features; and b) no significant increase in complication rates. Methods. A retrospective case series of iNPH patients was undertaken with 24 patients who had the proGAV shunt system inserted with an initial opening pressure of 5cmH2O. ...

Management of headache in a subgroup of shunted idiopathic intracranial hypertension (IIH) patients is a well- described and difficult task. We present our series of shunted IIH patients with medication overuse headache (MOH) and discuss the role of careful pain management in this group of patients.A retrospective review of shunted IIH patients with headache, who had their shunt function assessed by monitoring their intracranial pressure and were subsequently diagnosed with MOH.A total of 15 patients were identified. The mean time between the diagnosis of IIH and the diagnosis of medication overuse headache was 6 years (standard deviation 4.9, range 2-18 years). The majority of patients in this group (12/15) had undergone multiple shunt revisions.Medication overuse headache in shunted IIH patients can lead to the requirement of hospital admission, investigations and procedures. We suggest that opiates and non-steroidal anti-inflammatory analgesics (NSAIDs) are used for a specified duration post-operatively and reviewed regularly. We suggest that patients are counselled regarding medication overuse headache in a multidisciplinary setting.

Intracranial arteriovenous shunts (AVSs) in children can be divided into pial arteriovenous malformations, vein of Galen malformations, and arteriovenous fistulae (AVF). Dural AVF and dural sinus malformations are rare entities within this group. The relative immaturity of the anatomy and physiology of the neonatal and infant brain results in the inability of the hydrovenous system to compensate in the face of such disorders. Thus, the clinical presentation reflects this difference in the underlying anatomy, physiology, and disorder between children and adults. In this article, we briefly review the presentation, natural history and management of these entities.

Childhood intracranial aneurysms differ from those in the adult population in incidence and gender prevalence, cause, location, and clinical presentation. Endovascular treatment of pediatric aneurysms is the suggested approach because it offers both reconstructive and deconstructive techniques and a better clinical outcome compared with surgery; however, the long-term durability of endovascular treatment is still questionable, therefore long-term clinical and imaging follow-up is necessary. The clinical presentation, diagnosis, and treatment of intracranial aneurysms in children are discussed, and data from endovascular treatments are presented.

Idiopathic intracranial hypertension (IIH) is characterised by an increased intracranial pressure (ICP) in the absence of any central nervous system disease or structural abnormality and by normal CSF composition. Management becomes complicated once surgical intervention is required. Venous sinus stenosis has been suggested as a possible aetiology for IIH. Venous sinus stenting has emerged as a possible interventional option. Evidence for venous sinus stenting is based on elimination of the venous pressure gradient and clinical response. There have been no studies demonstrating the immediate effect of venous stenting on ICP. Patients with a potential or already known diagnosis of IIH were investigated according to departmental protocol. ICP monitoring was performed for 24 h. When high pressures were confirmed, CT venogram and catheter venography were performed to look for venous stenosis to demonstrate a pressure gradient. If positive, venous stenting would be performed and ICP monitoring would continue for a further 24 h after deployment of the venous stent. Ten patients underwent venous sinus stenting with concomitant ICP monitoring. Nine out of ten patients displayed an immediate reduction in their ICP that was maintained at 24 h. The average reduction in mean ICP and pulsatility was significant (p = 0.003). Six out of ten patients reported a symptomatic improvement within the first 2 weeks. Venous sinus stenting results in an immediate reduction in ICP. This physiological response to venous stenting has not previously been reported. Venous stenting could offer an alternative treatment option in correctly selected patients with IIH.

Idiopathic normal pressure hydrocephalus is predominantly a disease of the elderly. By its nature, many of those who present to clinic are in advanced old age with multiple comorbidities. Majority of patients treated are younger than 80 years old. We present the clinical outcomes and complication rates of patients over the age of 80 years at the time of operation, during the past 11 years at a single institution. Retrospective analysis of clinical records of all patients over the age of 80 years, who presented to our institution between 2006 and 2016. Results were analysed for co-morbidities, immediate and delayed complications, change in mobility/cognitive function post shunting of hydrocephalus. 39 patients (24 male, 15 female) met criteria. Mean [SD] age at the time of shunt insertion was 84 years (+/− 3.22) (range 80–94). No patients developed immediate CSF infection or sub-dural collection, or extended length of stay due to surgical or anaesthetic complications. There were no peri-operative or anaesthetic complications. 4 patients required a delayed surgical revision to encourage greater CSF drainage. 3 patients went on to develop delayed subdural haematoma, 1 of which was associated with trauma, 2 through overdrainage. 1 patient experienced poor post-operative wound healing and subsequently underwent removal of shunt. Of the 34 patient followed up, 27 patients (79.4%) improved in their mobility. (64.7%) patients/families reported symptomatic improvement in their cognition and memory. 6 (17.7%) patients did not experience an improvement in either mobility or cognitive function. Our data supports the assertion that, with proper patient selection, shunting of the over 80s with iNPH is a safe and effective procedure.

Intracranial pressure monitoring is commonly undertaken to assess and manage acute patients following head injury. However, ICP monitoring can also be a useful diagnostic tool in the management of CSF dynamics in elective patients. To date, there is little published research to suggest how long these elective patients require ICP monitoring in order to gain an accurate picture of a patient’s ICP dynamics. At the author’s institution, a minimum of 48-h data collection is currently undertaken in patients with a suspected ICP abnormality. A retrospective audit was undertaken comparing overall median ICP and overall median pulse amplitude data at three time points, 24 h, 48 h and total time analysed (if longer than 48 h). Paired T-test was used to assess if there were statistically significant differences between 24-h versus 48-h monitoring and total duration of monitoring. All patients admitted over a 6-month period for ICPM who met the inclusion/exclusion criteria were included. Eighteen patients met the criteria. Median age was 45.8 years, range 22–83 years, 12 female and 6 male. No complications were experienced as a result of ICPM. Diagnosis included NPH, IIH, suspected shunt malfunction and Chiari malformation. The results demonstrated that there is no statistical difference between 24 h and 48 h or longer for both overall median ICP and pulse amplitude. The results of this study demonstrate that ICP monitoring of elective adult patients using a Spiegelberg intraparenchymal bolt for 24 h gives an accurate picture of a patient’s ICP dynamics compared with longer periods of monitoring.

OBJECTIVEThe peritoneal cavity is widely used as the destination of choice for cerebrospinal fluid shunts. Various alternative sites have been used, particularly in the presence of certain contraindications. The pleural cavity has been used; however, a paucity of evidence details ventriculopleural (VPL) shunt survival, complication, and revision rates in adults. The aim of this study was to present a single center's experience with VPL shunts, identifying complication, revision, and survival rates.METHODSA single-center, retrospective case series analysis was conducted for VPL shunt insertions and revisions over a period of 5 years. Demographic as well as clinical data were collected. Ventriculopleural shunt survival was assessed using Kaplan-Meier curves and the log rank (Cox-Mantel) test.RESULTSTwenty-two VPL shunts were inserted in 19 patients. Median survival of the VPL shunts was 14 months. Pathological indication for the VPL shunt did not significantly affect survival. A total of 10 complications was observed: 2 infections, 2 cases of overdrainage, 2 obstructions, 1 distal catheter retraction, 2 symptomatic pleural effusions, and 1 asymptomatic pleural effusion.CONCLUSIONSVentriculopleural shunting is a safe and viable second-line procedure for cases in which ventriculoperitoneal shunts are unsuitable. While VPL shunts have a high revision rate, their complication rate is comparable to that of VP shunts. Ventriculopleural shunt survival can be improved by careful patient selection and the implementation of a combination of valves with antisiphon devices.

BACKGROUND: Overdrainage is a common complication associated with shunt insertion in normal-pressure hydrocephalus (NPH) patients. Using adjustable valves with antigravity devices has been shown to reduce its incidence. The optimal starting setting of an adjustable shunt valve in NPH is debatable.OBJECTIVE: To audit our single-center practice of setting adjustable valves.METHODS: We performed a retrospective review of clinical records of all NPH patients treated in our unit between 2006 and 2009 by the insertion of shunts with a proGAV valve, recording demographic and clinical data, shunt complications, and revision rates. Radiological reports of postoperative follow-up computed tomography scans of the brain were reviewed for detected subdural hematomas.RESULTS: A proGAV adjustable valve was inserted in 50 probable NPH patients between July 2006 and November 2009. Mean +/- SD age was 76 +/- 7 years. Mean follow-up was 15 months. The initial shunt setting was 6 +/- 3 cm H2O, and the final setting was 4.9 +/- 1.9 cm H2O. Nineteen patients required 24 readjustment procedures (readjustment rate, 38%; readjustment number, 0.48 times per patient). One patient (2%) developed delayed bilateral subdural hematoma after readjustment of his shunt valve setting as an outpatient.CONCLUSION: Starting with a low opening pressure setting on a proGAV adjustable shunt valve does not increase the chances of overdrainage complications and reduces the need for repeated readjustments.

ObjectivesA subset of idiopathic Normal Pressure Hydrocephalus (NPH) patients respond to VP shunt insertion temporarily. Adjustable anti-gravity devices are designed to control position-induced CSF drainage changes; we aim to assess to effect of using these devices to achieve controlled overdrainage in temporary shunt responders.DesignA single-centre retrospective study of patients undergoing VP shunt valve revision from an adjustable differential pressure valve with fixed anti-siphon (ProGAV +Shuntassistant) to a system incorporating an adjustable anti-siphon valve (ProGAV +ProSA) (April 2013-April 2018).Subjects21 patients diagnosed with temporary shunt-responsive NPH who improved on high volume shunt reservoir tap (10M: 11F). Mean age at first VP shunt insertion was 74.5±7.87 years.MethodsMedical records were retrospectively reviewed for demographics, interventions and clinical outcomes.ResultsMean duration until revision with a ProSA valve was 31.5±16.8 months (mean ±SD). Mean follow up was 31.4±15.9 months. Of 20 patients with sufficient follow-up, 12 made objective improvements in walking and/or neuropsychological test outcome. 15 patients made subjective improvements in mobility or cognitive impairment.ConclusionsVP shunting with adjustable differential pressure valves and fixed antigravity devices may not drain sufficient CSF for optimum management of low pressure hydrocephalus. Addition of adjustable anti-gravity devices at lower shunt settings in temporary shunt responders may improve outcome.

ObjectivesAcetazolamide has frequently been used as a first-line treatment for idiopathic Intracranial Hypertension (IIH) and other disorders which lead to a non-acute rise in intracranial pressure (ICP). The effect of acetazolamide has been observed through lumbar puncture, however the effect of acetazolamide on ICP has not been studied in continuous ICP measurement.DesignA retrospective study of a prospectively built ICP databaseSubjectsAll patients with continuous ICP monitoring demonstrating 24 hours on and 24 hours off acetazolamide were included in the study.MethodsPatients median ICP and median pulse amplitude over 24 hour monitoring period on and off Diamox was assessed.Results12 patients (9F, 3M) underwent ICP monitoring with data collected during the same admission. 8 patients had IIH, 1 Chiari Malformation, 3 new diagnostic ICP procedures. 10 patients saw a reduction in ICP while on acetazolamide. Overall, patients experienced a Median reduction of 1.14 mmHg (Mean 1.16 mmHg, Range 4.24 to −4.445 mmHg). Patients (n9) who were on ≥1 g of acetazolamide per day experienced a median reduction in ICP of 1.595 mmHg (Mean 1.91 mmHg, Range 4.24–0.5 mmHg).ConclusionsOur data suggests acetazolamide can reduce ICP quickly following commencement, however this reduction was relatively small. The effect seems greater with a higher dose. Larger numbers of patients are required to gain a greater understanding into the significance of acetazolamide on ICP, particularly the affect at larger doses.

ObjectivesPatients with Parkinson’s disease (PD) presenting with worsening gait and ventriculomegaly could have underlying normal pressure hydrocephalus (NPH). We aim to identify features of concurrent PD and NPH, assess investigations and benefits of intervention.DesignSingle-centre retrospective cohort study of patients diagnosed with PD and NPH, presenting to neurosurgery between April 2004 – April 2018.Subjects24 patients (20M: 4F) with concurrent PD and NPH, mean age 74.5±6.49 years (mean ±SD). 22 patients were diagnosed with PD prior to NPH diagnosis.MethodsMedical records were studied for demographics, symptoms, and response to ventriculoperitoneal (VP) shunting. Chi-square test was used to compare frequency of post-operative symptoms against a local database of NPH patients.ResultsAll patients presented to neurosurgery with gait disturbances, 21/24 with cognitive impairment, and 18/24 with urinary incontinence. 19 patients underwent VP shunt insertion; 5 patients were not suitable having failed a lumbar drain trial. Patients with PD and NPH improved in walking test outcomes and in urinary continence similarly to other NPH patients. Cognitive impairment did not respond well to VP shunting in patients with concurrent PD, significantly less than NPH patients without PD (pConclusionsDiagnosis of NPH in patients with PD is a complex clinical problem due to frequent overlap of symptoms. Benefits may be gained if this subset of patients do reach neurosurgical services and receive intervention.

ObjectivesComparing surgical versus endovascular management of pericallosal artery aneurysm.DesignRetrospective case series.SubjectsPatients managed in our unit for pericallosal artery aneurysms.MethodsPatients medical and radiological records were reviewed collecting data about presentation, management, complications. Clinical outcome was assessed by mRS at 3,6 and 12 months. Imaging were reviewed to report aneurysm size and treatment outcome.ResultsAverage follow up period 3.3 years SD ±3.5. 38 patients had SAH and 19 were incidentally discovered. Initial CT showed SAH in 21 patients, IVH in 3,ICH in 3 IVH and ICH in 9. 33 patients treated using endovascularly, 13 patients conservatively and 2 by surgical clipping. 33% of endovascular group had stroke caused by approach related complications. 41.3% of the patients had mRS (0–2) at 3 months period. Increased to 46.5% at 12 months. Average imaging follow up was 1.5 years (SD ±1.6). 36.3% of endovascular group showed aneurysm remnant filling or recurrence.ConclusionsPericallosal artery aneurysms are complex in nature and both management modalities are challenging. Complications were high in endovascular group. Surgical intervention should be considered in selected patients where complex intervention is required.

ObjectivesTimely and correct prescription of patients’ regular medications on admission to neurosurgical unit is noticed not to be fully compliant with set standards. This audit aims to review the practice of medication prescription by junior doctors during patient admission to a national neurosurgical unit, and to identify areas of improvement for prompt and accurate prescription.DesignProspective clinical audit.Subjects130 patients admitted to the neurosurgical unit in 2 weeks.MethodsPrescription of patient’s regular medications on admission was audited. The prescription practice was compared against the set standards, and between different settings (in-hour vs. out-of-hour, emergency vs. elective, experienced vs. new SHOs).Results18% of patients had no regular medications prescribed by clerking doctors, the majority of which were elective admissions during in-hour clerking and performed by experienced SHOs. Of the patients who had their regular medications prescribed on admission, 29% were prescribed inaccurately, and 16% in wrong doses. Total percentage of missed and error prescription was 46%, in which only 18% were corrected within 24 hours and 21% corrected up to 48 hours after admission.ConclusionsAreas of improvement identified: prescription practice of experienced SHOs during elective admissions, medication and dose check on prescription in both elective and emergency settings, medication reconciliation within 24 hours and thereafter. Changes (e.g. an alert system) are being implemented and re-audit is in plan.