Overlap and Differences in Migraine and Idiopathic Intracranial Hypertension.

PURPOSE OF REVIEW: Migraine and idiopathic intracranial hypertension (IIH) are increasingly encountered but remain enigmatic. This review compares the similarities and differences of the diagnostic criteria, pathophysiology, and risk factors for chronic migraine and IIH. RECENT FINDINGS: While migraine and IIH are distinct diseases, both conditions are frequently found concurrently and may share a link. Increased intracranial pressure (ICP) in those with or without pre-existing migraine may present with migraine-like headaches and contribute to migraine chronification. Increased intracranial pressure may be a coincidental occurrence in patients with migraine and normalization of pressure does not always translate to headache improvement. Limited information is available regarding the standard of treatment for patients with chronic migraine and IIH without papilledema. There continues to be controversy over the normal range of cerebral spinal fluid (CSF) values. Recognizing the concurrence of both conditions advances our understanding of headache pathology and demonstrates a striking need for more research.

Retinal hemorrhages due to intracranial hypertension, is it possible to differentiate them from those associated with abuse?

BACKGROUND: Retinal hemorrhages (RHs) are suggestive of abusive head trauma (AHT). Even so, controversy persists about other possible causes, a fact that hinders the diagnosis of abuse. OBJECTIVE: To determine the prevalence and patterns of RHs associated with increased intracranial pressure (ICP) in young children. PARTICIPANTS AND METHODS: Prospective, single center study of children aged 29 days-3 years undergoing a lumbar puncture with opening pressure (OP) measured during routine clinical care in the emergency department, over a 4-year period. Children with known causes of RHs were excluded. All the children underwent a detailed ophthalmological examination within 72 h of admission. For children with RHs, an in-depth investigation was carried out to rule out AHT. RESULTS: Thirty-four patients were included: 20(58.8 %) were boys, median age 11.7 months (range 1-33 months). Overall, 29(85.3 %) had clinical findings of increased ICP. The duration of symptoms was ≤4 days in all patients except one, in whom it was 1.5 months. The median OP was 27cmH2O (range 20-60cmH2O). One of the children was found to have RHs, with evaluation resulting in a diagnosis of AHT. No RHs were found in any of the others studied. Using the Wilson method, we can be confident to an upper limit of 95 % that the probability of RHs occurring secondary to increased ICP alone is at most 0.1. CONCLUSIONS: RHs were not detected in patients with isolated nontraumatic increased ICP, measured via OP and diagnosed in the ED. Therefore, if RHs are detected, investigation into the possibility of AHT is warranted.

Intracranial Pressure Monitoring in Moderate Traumatic Brain Injury: A Systematic Review and Meta-Analysis.

BACKGROUND: The principal aim of this study was to determine the prevalence of intracranial pressure (ICP) monitoring and intracranial hypertension (IHT) in patients treated for moderate traumatic brain injury (TBI). A secondary objective was to assess factors associated with ICP monitoring. METHODS: We conducted a systematic review of the literature to identify studies that assessed ICP monitoring in moderate TBI. The meta-analysis was performed by using a random-effects model. RESULTS: A total of 13 studies comprising 116,714 patients were pooled to estimate the overall prevalence of ICP monitoring and IHT (one episode or more of ICP > 20 mm Hg) after moderate TBI. The prevalence rate for ICP monitoring was 18.3% (95% confidence interval 8.1-36.1%), whereas the proportion of IHT was 44% (95% confidence interval 33.8-54.7%). Three studies were pooled to estimate the prevalence of ICP monitoring according to Glasgow Coma Scale (GCS) (≤ 10 vs. > 10). ICP monitoring was performed in 32.2% of patients with GCS ≤ 10 versus 15.2% of patients with GCS > 10 (p = 0.59). Both subgroups were highly heterogeneous. We found no other variables associated with ICP monitoring or IHT. CONCLUSIONS: The prevalence of ICP monitoring in moderate TBI is low, but the prevalence of IHT is high among patients undergoing ICP monitoring. Current literature is limited in size and quality and does not identify factors associated with ICP monitoring or IHT. Further research is needed to guide the optimal use of ICP monitoring in moderate TBI.

The role of Cushing's reflex and the vasopressin-mediated oligoanuric response to intracranial hypertension in patients with abdominal compartment syndrome.

BACKGROUND: We examined the link between increased intra-abdominal pressure, intracranial pressure, and vasopressin release as a potential mechanism. Intra-abdominal pressure, produced by abdominal-cavity insufflation with carbon dioxide (CO2) during laparoscopic abdominal procedures to facilitate visualization, is associated with various complications, including arterial hypertension and oliguria. METHODS: Mean arterial pressure, optic nerve sheath diameter, measured as a proxy for intracranial pressure, plasma vasopressin, serum and urine osmolarity, and urine output were measured 4 times during laparoscopic sleeve gastrectomy in 42 patients: before insufflation with CO2 (T0); after insufflation to 15 cm water (H2O) pressure, with 5 cm H2O positive end-expiratory pressure (T1); after positive end-expiratory pressure was raised to 10 cm H2O (T2); and after a return to the baseline state (T3). Mean values at T0 to T3 and the directional consistency of changes (increase/decrease/ unchanged) were compared among the 4 data-collection points. RESULTS: Statistically significant elevations (all P ≤ .001) were noted from T0 to T1 and from T0 to T2 in mean arterial pressure, optic nerve sheath diameter, and vasopressin, followed by decreases at T3. For optic nerve sheath diameter and vasopressin, the increases at T1 and T2 occurred in 98% and 100% of patients, ultimately exceeding normal levels in 88 and 97%, respectively. Conversely, urine output fell from T0 to T1 and T2 by 60.9 and 73.4%, decreasing in 88.1% of patients (all P < .001). Patients with class II obesity exhibited statistically greater increases in optic nerve sheath diameter and vasopressin, but statistically less impact on urine output, than patients with class III obesity. CONCLUSION: Increased mean arterial pressure, intracranial pressure, and vasopressin release appear to be intermediary steps between increased intra-abdominal pressure and oliguria. Further research is necessary to determine any causative links between these physiological changes.

Cerebrospinal fluid dynamics in idiopathic intracranial hypertension: a literature review and validation of contemporary findings.

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a rare disease of unknown aetiology related possibly to disturbed cerebrospinal fluid (CSF) dynamics and characterised by elevated intracranial pressure (ICP) causing optic nerve atrophy if not timely treated. We studied CSF dynamics of the IIH patients based on the available literature and our well-defined cohort. METHOD: A literature review was performed from PubMed between 1980 and 2020 in compliance with the PRISMA guideline. Our study includes 59 patients with clinical, demographical, neuro-ophthalmological, radiological, outcome data, and lumbar CSF pressure measurements for suspicion of IIH; 39 patients had verified IIH while 20 patients did not according to Friedman's criteria, hence referred to as symptomatic controls. RESULTS: The literature review yielded 19 suitable studies; 452 IIH patients and 264 controls had undergone intraventricular or lumbar CSF pressure measurements. In our study, the mean CSF pressure, pulse amplitudes, power of respiratory waves (RESP), and the pressure constant (P0) were higher in IIH than symptomatic controls (p < 0.01). The mean CSF pressure was higher in IIH patients with psychiatric comorbidity than without (p < 0.05). In IIH patients without acetazolamide treatment, the RAP index and power of slow waves were also higher (p < 0.05). IIH patients with excess CSF around the optic nerves had lower relative pulse pressure coefficient (RPPC) and RESP than those without (p < 0.05). CONCLUSIONS: Our literature review revealed increased CSF pressure, resistance to CSF outflow and sagittal sinus pressure (SSP) as key findings in IIH. Our study confirmed significantly higher lumbar CSF pressure and increased CSF pressure waves and RAP index in IIH when excluding patients with acetazolamide treatment. In overall, the findings reflect decreased craniospinal compliance and potentially depleted cerebral autoregulation resulting from the increased CSF pressure in IIH. The increased slow waves in patients without acetazolamide may indicate issues in autoregulation, while increased P0 could reflect the increased SSP.

Prevalence of Incidentally Detected Signs of Intracranial Hypertension on Magnetic Resonance Imaging and Their Association With Papilledema.

Importance: Magnetic resonance imaging (MRI) signs of intracranial hypertension (IH) are traditionally associated with idiopathic intracranial hypertension (IIH), but these signs are also detected among individuals with primary headaches and among asymptomatic individuals without papilledema. Objective: To examine the prevalence of MRI signs of IH among consecutive outpatients undergoing brain MRI for any clinical indication and to explore their association with papilledema. Design, Setting, and Participants: This prospective cross-sectional study of outpatients undergoing brain MRI at 1 outpatient imaging facility was conducted between August 1, 2019, and March 31, 2020, with ocular fundus photographs taken concurrently. Radiographic images from consecutive adult patients who were undergoing brain MRI and able to participate in fundus photography were analyzed for MRI signs of IH. A univariate analysis using either Fisher exact tests or t tests was performed. Main Outcomes and Measures: Prevalence of MRI signs of IH and prevalence of papilledema detected on ocular fundus photographs. Radiographic signs of IH included empty sella, optic nerve head protrusion, posterior scleral flattening, increased perioptic cerebrospinal fluid, optic nerve tortuosity, enlarged Meckel caves, cephaloceles, cerebellar tonsillar descent, and bilateral transverse venous sinus stenosis. Results: A total of 388 patients were screened for eligibility; of those, 92 patients were excluded (58 declined participation, 16 were unable to consent, 14 were unable to complete fundus photography, and 4 completed MRI and fundus photography twice, so their second set of findings was removed). Among the 296 patients included in the study, the median age was 49.5 years (interquartile range, 37.8-62.0 years), and 188 patients (63.5%) were female. The most common indication for MRI was surveillance of a brain neoplasm (82 patients [27.7%]). Investigations of headaches (26 patients [8.8%]) and disorders of intracranial pressure (4 patients [1.4%]) were uncommon. At least 1 radiographic sign of IH was present in 145 patients (49.0%). Among 296 total study patients, 98 patients (33.1%) had empty sella, 47 patients (15.9%) had enlarged Meckel caves, 32 patients (10.8%) had increased perioptic cerebrospinal fluid, 23 patients (7.8%) had optic nerve tortuosity, 2 patients (0.7%) had scleral flattening, and 4 patients (1.4%) had cephaloceles. Bilateral transverse venous sinus stenosis was present in 6 of 198 patients (3.0%). Five patients (1.7%) had papilledema. Compared with patients without papilledema, those with papilledema had a significantly higher body mass index and history of IIH, in addition to an increased prevalence of empty sella, optic nerve tortuosity, and transverse venous sinus stenosis detected on MRI. The prevalence of papilledema increased from 2.8% among patients with at least 1 MRI sign of IH to 40.0% among patients with 4 or more MRI signs of IH. Conclusions and Relevance: Magnetic resonance imaging signs of IH were common among patients undergoing brain MRI in this study but rarely associated with papilledema. The management of patients with incidentally detected signs of IH likely does not require systematic lumbar puncture unless concerning symptoms or papilledema are present.

Secondary Cerebral Ischemia at Traumatic Brain Injury Is More Closely Related to Cerebrovascular Reactivity Impairment than to Intracranial Hypertension.

The purpose of this study was to investigate the relationship between the development of secondary cerebral ischemia (SCI), intracranial pressure (ICP) and cerebrovascular reactivity (CVR) after traumatic brain injury (TBI). METHODS: 89 patients with severe TBI with ICP monitoring were studied retrospectively. The mean age was 36.3 ± 4.8 years, 53 men, 36 women. The median Glasgow Coma Score (GCS) was 6.2 ± 0.7. The median Injury Severity Score was 38.2 ± 12.5. To specify the degree of impact of changes in ICP and CVR on the SCI progression in TBI patients, logistic regression was performed. Significant p-values were <0.05. RESULTS: The deterioration of CVR in combination with the severity of ICP has a significant impact on the increase in the prevalence rate of SCI. A logistic regression analysis for a model of SCI dependence on intracranial hypertension and CVR was performed. The results of the analysis showed that CVR was the most significant factor affecting SCI development in TBI. CONCLUSIONS: The development of SCI in severe TBI depends largely on CVR impairment and to a lesser extent on ICP level. Treatment for severe TBI patients with SCI progression should not be aimed solely at intracranial hypertension correction but also at CVR recovery.

Ventriculoperitoneal Shunt for CNS Metastasis in Breast Cancer: Clinical Outcomes Based on Intrinsic Subtype.

BACKGROUND: Leptomeningeal metastasis (LM) is associated with a grave prognosis in breast cancer (BC) and can be controlled with a ventriculoperitoneal shunt (VPS). Information regarding LM and VPS based on intrinsic subtype is limited; thus, we investigated the clinical outcomes of BC treated with VPS. PATIENTS AND METHODS: The present retrospective study comprised 70 patients diagnosed with LM who received a VPS. The patients were divided into 4 groups based on BC subtype: hormone receptor (HR)+/human epidermal growth factor receptor 2 (HER2)-, HR+/HER2+, HR-/HER2+, and triple negative BC (TNBC). RESULTS: The most common indications for VPS were uncontrolled intracranial pressure (57.1%) and uncontrolled headache (55.7%), which improved in 54 (77.1%) of 70 patients after VPS. The median overall survival (OS) after brain or LM and overall survival after VPS were 7.6 and 2.3 months, respectively. Anti-HER2 treatment was a significant prognostic factor for better OS after brain or LM based on multivariate analysis (hazard ratio, 0.15; 95% confidence interval, 0.04-0.57; P = .005), whereas TNBC was correlated with shorter OS after central nervous system metastasis (hazard ratio, 2.82; 95% confidence interval, 1.46-5.48; P = .002). CONCLUSIONS: There were significant differences in clinical outcome based on the intrinsic subtype of patients with BC with LM who received a VPS. Anti-HER2 treatment in patients with HER2+ BC was associated with better survival in patients with metastatic BC with VPS insertion compared with those without. Survival of metastatic BC with VPS remained poor, especially in the TNBC subgroup.

Robot-Assisted Stereotactic Biopsies in 377 Consecutive Adult Patients with Supratentorial Diffuse Gliomas: Diagnostic Yield, Safety, and Postoperative Outcomes.

BACKGROUND: Multiple biopsy samples are warranted for the histomolecular diagnosis of diffuse gliomas in the current molecular era, which possibly increases morbidity. OBJECTIVE: We assessed diagnostic yield, safety, and risk factors of postoperative morbidity after robot-assisted serial stereotactic biopsy sampling along 1 biopsy trajectory for diffuse gliomas. METHODS: Observational retrospective analysis of consecutive magnetic resonance imaging-based robot-assisted stereotactic biopsies performed at a single institution to assess the diagnosis of nonresectable newly diagnosed supratentorial diffuse gliomas in adults (2006-2016). RESULTS: In 377 patients, 4.2 ± 1.9 biopsy samples were obtained at 2.6 ± 1.2 biopsy sites. The histopathologic diagnosis was obtained in 98.7% of cases. Preoperative neurologic deficit (P = 0.030), biopsy site hemorrhage ≥20 mm (P = 0.004), and increased mass effect on postoperative imaging (P = 0.014) were predictors of a new postoperative neurologic deficit (7.7%). Postoperative neurologic deficit (P < 0.001) and increased mass effect on postoperative imaging (P = 0.014) were predictors of a Karnofsky Performance Status decrease ≥20 points postoperatively (4.0%). Increased intracranial pressure preoperatively (P = 0.048) and volume of the contrast-enhanced area ≥13 cm3 (P = 0.048) were predictors of an increased mass effect on postoperative imaging (4.4%). Preoperative Karnofsky Performance Status <70 (P = 0.045) and increased mass effect on postoperative imaging (P < 0.001) were predictors of mortality 1 month postoperatively (2.9%). Preoperative neurologic deficit (P = 0.005), preoperative Karnofsky Performance Status <70 (P < 0.001), subventricular zone contact (P = 0.004), contrast enhancement (P = 0.018), and steroid use (P = 0.003), were predictors of the inability to discharge to home postoperatively (37.0%). CONCLUSIONS: Robot-assisted stereotactic biopsy sampling results in high diagnostic accuracy with low complication rates. Multiple biopsy sites and samples do not increase postoperative complications.

Patient-specific ICP Epidemiologic Thresholds in Adult Traumatic Brain Injury: A CENTER-TBI Validation Study.

BACKGROUND: Patient-specific epidemiologic intracranial pressure (ICP) thresholds in adult traumatic brain injury (TBI) have emerged, using the relationship between pressure reactivity index (PRx) and ICP, displaying stronger association with outcome over existing guideline thresholds. The goal of this study was to explore this relationship in a multi-center cohort in order to confirm the previous finding. METHODS: Using the Collaborative European Neuro Trauma Effectiveness Research in TBI (CENTER-TBI) high-resolution intensive care unit cohort, we derived individualized epidemiologic ICP thresholds for each patient using the relationship between PRx and ICP. Mean hourly dose of ICP was calculated for every patient for the following thresholds: 20, 22 mm Hg and the patient's individual ICP threshold. Univariate logistic regression models were created comparing mean hourly dose of ICP above thresholds to dichotomized outcome at 6 to 12 months, based on Glasgow Outcome Score-Extended (GOSE) (alive/dead-GOSE≥2/GOSE=1; favorable/unfavorable-GOSE 5 to 8/GOSE 1 to 4, respectively). RESULTS: Individual thresholds were identified in 65.3% of patients (n=128), in keeping with previous results (23.0±11.8 mm Hg [interquartile range: 14.9 to 29.8 mm Hg]). Mean hourly dose of ICP above individual threshold provides superior discrimination (area under the receiver operating curve [AUC]=0.678, P=0.029) over mean hourly dose above 20 mm Hg (AUC=0.509, P=0.03) or above 22 mm Hg (AUC=0.492, P=0.035) on univariate analysis for alive/dead outcome at 6 to 12 months. The AUC for mean hourly dose above individual threshold trends to higher values for favorable/unfavorable outcome, but fails to reach statistical significance (AUC=0.610, P=0.060). This was maintained when controlling for baseline admission characteristics. CONCLUSIONS: Mean hourly dose of ICP above individual epidemiologic ICP threshold has stronger associations with mortality compared with the dose above Brain Trauma Foundation defined thresholds of 20 or 22 mm Hg, confirming prior findings. Further studies on patient-specific epidemiologic ICP thresholds are required.

Spontaneous Skull Base Cerebrospinal Fluid Leaks and Their Relationship to Idiopathic Intracranial Hypertension.

BACKGROUND: The association between spontaneous skull base cerebrospinal fluid (CSF) leaks and idiopathic intracranial hypertension (IIH) has been suggested, but its significance remains unclear. OBJECTIVE: To estimate the prevalence of IIH in spontaneous skull base CSF leak patients. METHODS: Systematic collection of demographics, neuro-ophthalmic and magnetic resonance imaging evaluation of spontaneous skull base CSF leak patients seen pre- and post-leak repair in one neuro-ophthalmology service. Patients with preexisting IIH were diagnosed with definite IIH if adequate documentation was provided; otherwise, they were categorized with presumed IIH. Classic radiographic signs of intracranial hypertension and bilateral transverse venous sinus stenosis were recorded. RESULTS: Thirty six patients were included (age [interquartile range]: 50 [45;54] years; 94% women; body mass index: 36.8 [30.5;39.9] kg/m2), among whom six (16.7%, [95% confidence interval, CI]: [6.4;32.8]) had a preexisting diagnosis of definite or presumed IIH. Of the remaining 30 patients, four (13.3%, 95%CI: [3.8;30.7]) had optic nerve head changes suggesting previously undiagnosed IIH, while one was newly diagnosed with definite IIH at initial consultation. One out of 29 patients with normal findings of the optic nerve head at presentation developed new onset papilledema following surgery (3.4%, 95%CI: [0.1;17.8]) and was ultimately diagnosed with definite IIH. Overall, the prevalence of definite IIH was 19.4% (95%CI: [8.2;36.0]). CONCLUSION: Striking demographic overlap exists between IIH patients and those with spontaneous CSF leak. Definite IIH was present in approximately 20% of our patients. However, its true prevalence is likely higher than identified by using classic criteria. We therefore hypothesize that an active CSF leak serves as an auto-diversion for CSF, thereby "treating" the intracranial hypertension and eliminating characteristic signs and symptoms at initial presentation.

Isolated intracranial hypertension associated with COVID-19.

BACKGROUND: Headache is a frequent complaint in COVID-19 patients. However, no detailed information on headache characteristics is provided in these reports. Our objective is to describe the characteristics of headache and the cerebrospinal fluid (CSF) profile in COVID-19 patients, highlighting the cases of isolated intracranial hypertension. METHODS: In this cross-sectional study, we selected COVID-19 patients who underwent lumbar puncture due to neurological complaints from April to May 2020. We reviewed clinical, imaging, and laboratory data of patients with refractory headache in the absence of other encephalitic or meningitic features. CSF opening pressures higher than 250 mmH2O were considered elevated, and from 200 to 250 mmH2O equivocal. RESULTS: Fifty-six COVID-19 patients underwent lumbar puncture for different neurological conditions. A new, persistent headache that prompted a CSF analysis was diagnosed in 13 (23.2%). The pain was throbbing, holocranial or bilateral in the majority of patients. All patients had normal CSF analysis and RT-qPCR for SARS-CoV-2 was negative in all samples. Opening pressure >200 mmH2O was present in 11 patients and, in six of these, > 250 mmH2O. 6/13 patients had complete improvement of the pain, five had partial improvement, and two were left with a daily persistent headache. CONCLUSIONS: In a significant proportion of COVID-19 patients, headache was associated to intracranial hypertension in the absence of meningitic or encephalitic features. Coagulopathy associated with COVID-19 could be an explanation, but further studies including post-mortem analysis of areas of production and CSF absorption (choroid plexuses and arachnoid granulations) are necessary to clarify this issue.

Decompressive craniectomy in aneurysmal subarachnoid hemorrhage: Who and when? - A systematic review and meta-analysis.

OBJECTIVE: Decompressive craniectomy (DC) is a standard neurosurgical procedure against intractable intracranial hypertension. Patients with severe aneurysmal subarachnoid hemorrhage (aSAH) are prone to intracranial hypertension, necessitating DC in certain cases. However, the clinical utility of DC after aSAH remains unclear. Hereby we present a systematic review and meta-analysis summarizing the published studies on DC in aSAH patients. MATERIAL AND METHODS: We systematically searched PubMed, Scopus, Web of Science and Cochrane Library for articles published before Jul 10, 2019 reporting on rates, outcome, indications, timing and complications of SAH patients undergoing DC. RESULTS: Of 1085 identified unique records, 28 observational studies published between 1993 and 2018 were included. In total, data of 2788 aSAH patients was extracted including 2014 patients with DC. The mean DC rate was 10.9 % (range 3.3%-25.6%). Good initial clinical condition (p = 0.01; odds ratio (OR) = 2.93; confidence interval (95 % CI) 1.30-6.61) and younger patients' age (p = 0.02; mean difference (MD) = -4.50; 95 % CI -8.36 - -0.64) increased the chance of good outcome after DC. Overall, patients with primary DC showed a tendency towards better outcome than those that underwent secondary DC (p = 0.08; OR = 1.50; 95 % CI 0.96-2.35). Younger age (p < 0.00001; MD = -3.63; 95 % CI -5.20 to -2.06), presence of intracerebral hemorrhage (ICH; p < 0.00001; OR = 6.63; 95 % CI 3.98-11.03), poor initial clinical condition (p < 0.00001; OR = 4.81; 95 % CI 2.88-8.03) and treatment modality (coiling, p < 0.00001; OR = 0.19; 95 % CI 0.10-0.35) were associated with the indication to DC. CONCLUSIONS: Around 10 % of aSAH individuals undergo DC. Younger individuals, with poor initial clinical condition, additional ICH and aneurysm clipping are more likely to be selected for DC. Due to expected outcome benefit, younger individuals with good-grade aSAH should be considered for early decompression in case of increased intracranial pressure.

The incidence of obesity, venous sinus stenosis and cerebral hyperaemia in children referred for MRI to rule out idiopathic intracranial hypertension at a tertiary referral hospital: a 10 year review.

BACKGROUND: Children referred to a tertiary hospital for the indication, "rule out idiopathic intracranial hypertension (IIH)" may have an increased risk of raised venous sinus pressure. An increase in sinus pressure could be due to obesity, venous outflow stenosis or cerebral hyperemia. The purpose of this paper is to define the incidence of each of these variables in these children. METHODS: Following a data base review, 42 children between the ages of 3 and 15 years were found to have been referred over a 10 year period. The body mass index was assessed. The cross sectional areas and circumferences of the venous sinuses were measured at 4 levels to calculate the hydraulic and effective diameters. The arterial inflow, sagittal and straight sinus outflows were measured. Automatic cerebral volumetry allowed the brain volume and cerebral blood flow (CBF) to be calculated. The optic nerve sheath diameter was used as a surrogate marker of raised intracranial pressure (ICP). The sagittal sinus percentage venous return was used as a surrogate marker of elevated venous pressure. Age and sex matched control groups were used for comparison. RESULTS: Compared to controls, the obesity rates were not significantly different in this cohort. Compared to controls, those at risk for IIH had a 17% reduction in transverse sinus and 14% reduction in sigmoid sinus effective cross sectional area (p = 0.005 and 0.0009). Compared to controls, the patients at risk for IIH had an arterial inflow increased by 34% (p < 0.0001) with a 9% larger brain volume (p = 0.02) giving an increase in CBF of 22% (p = 0.005). The sagittal and straight sinus venous return were reduced by 11% and 4% respectively (p < 0.0001 and 0.0009) suggesting raised venous sinus pressure. Forty five percent of the patients were classified as hyperemic and these had optic nerve sheath diameters 17% larger than controls (p < 0.0002) suggesting raised ICP. CONCLUSION: In children with the chronic headache/ IIH spectrum, the highest associations were with cerebral hyperemia and mild venous sinus stenosis. Obesity was not significantly different in this cohort. There is evidence to suggest hyperemia increases the venous sinus pressure and ICP.

Anticoagulation delay does not affect the functional outcome of cerebral venous thrombosis.

Available knowledge about the impact of anticoagulation delay on outcomes of patients with cerebral venous thrombosis (CVT) is limited. We therefore assessed the factors influencing anticoagulation delay and investigated the effect of this delay on outcomes of CVT patients. Anticoagulation delay was defined as the time interval between symptom onset and anticoagulation initiation. The primary outcome was a modified Rankin Scale (mRS) score > 2 at the final follow-up. A total of 164 eligible patients were included. The median anticoagulation delay was 9 days. Cerebral hemorrhage on admission neuroimaging correlated with earlier anticoagulation (p = 0.040). Anticoagulation delay was not associated with poor functional outcome (mRS > 2), but it was associated with residual headache across the entire cohort (earlier anticoagulation: 15/76 [19.7%] vs. later anticoagulation: 28/79 [35.4%]; p = 0.029) and in the subgroup with isolated intracranial hypertension (earlier anticoagulation: 4/25 [16.0%] vs. later anticoagulation: 14/27 [51.9%]; p = 0.007). Anticoagulation delay was found to be common among patients with CVT. Anticoagulation delay was not associated with poor functional outcome, but may have led to an increased risk of residual headache across our entire cohort and in the subgroup with isolated intracranial hypertension.

Involvement of the Nervous System in SARS-CoV-2 Infection.

As a severe and highly contagious infectious disease, coronavirus disease 2019 (COVID-19) has caused a global pandemic. Several case reports have demonstrated that the respiratory system is the main target in patients with COVID-19, but the disease is not limited to the respiratory system. Case analysis indicated that the nervous system can be invaded by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and that 36.4% of COVID-19 patients had neurological symptoms. Importantly, the involvement of the CNS may be associated with poor prognosis and disease worsening. Here, we discussed the symptoms and evidence of nervous system involvement (directly and indirectly) caused by SARS-CoV-2 infection and possible mechanisms. CNS symptoms could be a potential indicator of poor prognosis; therefore, the prevention and treatment of CNS symptoms are also crucial for the recovery of COVID-19 patients.

The incidence of significant venous sinus stenosis and cerebral hyperemia in childhood hydrocephalus: prognostic value with regards to differentiating active from compensated disease.

BACKGROUND: Symptomatic or active hydrocephalus in children is linked to an elevation in intracranial pressure (ICP), which is likely to be multifactorial in origin. The CSF outflow resistance, venous sinus resistance and total cerebral blood flow are likely factors in the ICP elevation. The purpose of this paper is to define the incidence, site and significance of venous sinus stenosis and/or cerebral hyperemia in a cohort of children diagnosed with hydrocephalus at a tertiary referral hospital. METHODS: The imaging database was reviewed over a 10 year period and the index MRI of all children between the ages of 4 months and 15 years, who were diagnosed with treatment naive hydrocephalus of any type (excluding secondary to tumor) and had magnetic resonance venography (MRV) and flow quantification were selected. Patients were compared with children undergoing an MRI with MRV and flow quantification who were subsequently shown to have no abnormality. The cross-sectional area and circumference of the sinuses were measured at 4 levels. The hydraulic and effective diameters were calculated. An area stenosis of 65% or greater was deemed significant. A total cerebral blood flow greater than two standard deviations above the mean for controls was taken to be abnormal. RESULTS: There were a total of 55 children with hydrocephalus compared to 118 age matched control MRV's and 35 control flow quantification studies. A high grade stenosis occurred in 56% of patients but in none of the controls (p < 0.0001). The commonest site of narrowing was in the distal sigmoid sinus. Cerebral hyperemia occurred in 13% of patients but did not occur in the controls. CONCLUSIONS: The elevation in ICP in symptomatic hydrocephalus is multifactorial. Both high grade venous stenosis and cerebral hyperemia are common in childhood hydrocephalus. High grade stenosis was noted to be a risk factor for conservative management failure. Hyperemia was a good prognostic indicator.

Fulminant Idiopathic Intracranial Hypertension.

PURPOSE OF REVIEW: The goal of this review is to describe the presenting features of fulminant idiopathic intracranial hypertension (IIH) and outline the multimodal approach to its treatment. RECENT FINDINGS: Venous sinus stenting may be an appropriate alternative to optic nerve sheath fenestration or cerebrospinal fluid shunting in select patients with fulminant IIH. Prompt surgical intervention maximizes the chance of visual recovery in patients with fulminant IIH. "Fulminant IIH" is defined as intracranial hypertension with no secondary cause, severe vision loss within 4 weeks of symptom onset, and progressive vision loss over days. Rapid recognition of the fulminant phenotype of IIH by emergency department physicians, neurologists, and ophthalmologists is critical. Without appropriate triage and rapid medical and surgical intervention, patients with fulminant IIH are at high risk for profound, permanent vision loss. Prompt surgical intervention with optic nerve sheath fenestration, cerebrospinal fluid shunting, or venous sinus stenting minimizes the chance of poor visual outcome. If a delay is anticipated, serial lumbar punctures or temporary cerebrospinal fluid drainage and medical therapy may forestall irreversible vision loss.

EVENTS ASSOCIATED WITH THE OCCURRENCE OF INTRACRANIAL HYPERTENSION IN PEDIATRIC PATIENTS WITH SEVERE CRANIOENCEPHALIC TRAUMA AND MONITORING OF INTRACRANIAL PRESSURE.

OBJECTIVE: To determine the events associated with the occurrence of intracranial hypertension (ICH) in pediatric patients with severe cranioencephalic trauma. METHODS: This was a prospective cohort study of patients 18 years old and younger with cranioencephalic trauma, scores below nine on the Glasgow Coma Scale, and intracranial pressure monitoring. They were admitted between September, 2005 and March, 2014 into a Pediatric Intensive Care Unit. ICH was defined as an episode of intracranial pressure above 20 mmHg for more than five minutes that needed treatment. RESULTS: A total of 198 children and adolescents were included in the study, of which 70.2% were males and there was a median age of nine years old. ICH occurred in 135 (68.2%) patients and maximum intracranial pressure was 36.3 mmHg, with a median of 34 mmHg. A total of 133 (97.8%) patients with ICH received sedation and analgesia for treatment of the condition, 108 (79.4%) received neuromuscular blockers, 7 (5.2%) had cerebrospinal fluid drainage, 105 (77.2%) received mannitol, 96 (70.6%) received hyperventilation, 64 (47.1%) received 3% saline solution, 20 (14.7%) received barbiturates, and 43 (31.9%) underwent a decompressive craniectomy. The events associated with the occurrence of ICH were tomographic findings at the time of admission of diffuse or hemispheric swelling (edema plus engorgement). The odds ratio for ICH in patients with Marshall III (diffuse swelling) tomography was 14 (95%CI 2.8-113; p<0.003), and for those with Marshall IV (hemispherical swelling) was 24.9 (95%CI 2.4-676, p<0.018). Mortality was 22.2%. CONCLUSIONS: Pediatric patients with severe cranioencephalic trauma and tomographic alterations of Marshall III and IV presented a high chance of developing ICH.

Long-Term Effect of Decompressive Craniectomy on Intracranial Pressure and Possible Implications for Intracranial Fluid Movements.

BACKGROUND: Decompressive craniectomy (DC) is used in cases of severe intracranial hypertension or impending intracranial herniation. DC effectively lowers intracranial pressure (ICP) but carries a risk of severe complications related to abnormal ICP and/or cerebrospinal fluid (CSF) circulation, eg, hygroma formation, hydrocephalus, and "syndrome of the trephined." OBJECTIVE: To study the long-term effect of DC on ICP, postural ICP regulation, and intracranial pulse wave amplitude (PWA). METHODS: Prospective observational study including patients undergoing DC during a 12-mo period. Telemetric ICP sensors (Neurovent-P-tel; Raumedic, Helmbrechts, Germany) were implanted in all patients. Following discharge from the neuro intensive care unit (NICU), scheduled weekly ICP monitoring sessions were performed during the rehabilitation phase. RESULTS: A total of 16 patients (traumatic brain injury: 7, stroke: 9) were included (median age: 55 yr, range: 19-71 yr). Median time from NICU discharge to cranioplasty was 48 d (range: 16-98 d) and during this period, mean ICP gradually decreased from 7.8 ± 2.0 mm Hg to -1.8 ± 3.3 mm Hg (P = .02). The most pronounced decrease occurred during the first month. Normal postural ICP change was abolished after DC for the entire follow-up period, ie, there was no difference between ICP in supine and sitting position (P = .67). PWA was markedly reduced and decreased from initially 1.2 ± 0.7 mm Hg to 0.4 ± 0.3 mm Hg (P = .05). CONCLUSION: Following NICU discharge, ICP decreases to negative values within 4 wk, normal postural ICP regulation is lost and intracranial PWA is diminished significantly. These abnormalities might have implications for intracranial fluid movements (eg, CSF and/or glymphatic flow) following DC and warrants further investigations.