Pulsatile versus non-pulsatile tinnitus in idiopathic intracranial hypertension.

INTRODUCTION: 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). METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Effect of venous stenting on intracranial pressure in idiopathic intracranial hypertension.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Shunting of the over 80s in normal pressure hydrocephalus.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: Our data supports the assertion that, with proper patient selection, shunting of the over 80s with iNPH is a safe and effective procedure.

Early Postoperative Outcomes of Normal Pressure Hydrocephalus: Results of a Service Evaluation.

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.

Interpretation of lumbar cerebrospinal fluid leukocytosis after cranial surgery: The relevance of aseptic meningitis.

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.

Superficial and Deep Skin Preparation with Povidone-Iodine for Ventriculoperitoneal Shunt Surgery : A Technical Note.

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.

Natural history of ventriculomegaly in adults: a cluster analysis.

OBJECTIVE: Chronic ventriculomegaly in the absence of raised intracranial pressure (ICP) is a known entity in adult hydrocephalus practice. The natural history and indication for treatment is, however, poorly defined. A highly heterogeneous group, some adults with ventriculomegaly are asymptomatic, while others have life-threatening deteriorations. The authors hypothesized that the various presentations can be subtyped and represent different stages of decompensation. A cluster analysis was performed on a cohort of patients with chronic ventriculomegaly with the aim of elucidating typical clinical characteristics and outcomes in chronic ventriculomegaly in adults. METHODS: Data were collected from 79 patients with chronic ventriculomegaly referred to a single center, including demographics, presenting symptoms, and 24-hour ICP monitoring (ICPM). A statistical cluster analysis was performed to determine the presence of subgroups. RESULTS: Four main subgroups and one highly dissimilar group were identified. Patients with ventriculomegaly commonly have a perinatal event followed by one of four main presentations: 1) incidental ventriculomegaly with or without headache; 2) highly symptomatic presentation (including reduced consciousness) and raised ICP; 3) early presenting with symptoms of headache and nausea (with abnormal pulsatility); and 4) late presenting with features common to normal pressure hydrocephalus. Each symptomatic group has characteristic radiological features, ICPM, and responses to treatment. CONCLUSIONS: Cluster analysis has identified subgroups of adult patients with ventriculomegaly. Such groups may represent various degrees of decompensation. Surgical interventions may not be equally effective across the subgroups, presenting an avenue for further research. The identified subtypes provide further insight into the natural history of this lesser studied form of hydrocephalus.

Transtentorial Distortion Syndrome: Consistent Complication Following Lateral and Fourth Ventricular Shunting in Adults.

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).