Pediatric idiopathic intracranial hypertension - Is the fixed threshold value of elevated LP opening pressure set too high?

Ultrasound-guided initial diagnosis and follow-up of pediatric idiopathic intracranial hypertension

BACKGROUND

Idiopathic intracranial hypertension in children often presents with non-specific symptoms found in conditions such as hydrocephalus. For definite diagnosis, invasive intracranial pressure measurement is usually required. Ultrasound (US) of the optic nerve sheath diameter provides a non-invasive method to assess intracranial pressure. Transtemporal US allows imaging of the third ventricle and thus assessment for hydrocephalus.

OBJECTIVE

To investigate whether the combination of US optic nerve sheath and third ventricle diameter can be used as a screening tool in pediatric idiopathic intracranial hypertension to indicate elevated intracranial pressure and exclude hydrocephalus as an underlying pathology. Further, to analyze whether both parameters can be used to monitor treatment outcome.

MATERIALS AND METHODS

We prospectively included 36 children with idiopathic intracranial hypertension and 32 controls. Using a 12-Mhz linear transducer and a 1-4-Mhz phased-array transducer, respectively, optic nerve sheath and third ventricle diameters were determined initially and during the course of treatment.

RESULTS

In patients, the mean optic nerve sheath diameter was significantly larger (6.45±0.65 mm, controls: 4.96±0.32 mm) and the mean third ventricle diameter (1.69±0.65 mm, controls: 2.99±1.31 mm) was significantly smaller compared to the control group, P<0.001. Optimal cut-off values were 5.55 mm for the optic nerve sheath and 1.83 mm for the third ventricle diameter.

CONCLUSIONS

The combined use of US optic nerve sheath and third ventricle diameter is an ideal non-invasive screening tool in pediatric idiopathic intracranial hypertension to indicate elevated intracranial pressure while ruling out hydrocephalus. Treatment can effectively be monitored by repeated US, which also reliably indicates relapse.

Enhancing Diagnostic Accuracy Through Neuroimaging Revisions in Pediatric Pseudotumor Cerebri Syndrome: A Cross-Sectional Study

BACKGROUND

This cross-sectional study aimed to report all neuroimaging findings suggestive of raised intracranial pressure in children with pseudotumor cerebri syndrome (PTCS), before and after re-review by two neuroradiologists.

METHODS

We included 48 children aged <18 years diagnosed with PTCS between 2016 and 2021. Clinical and radiological data were obtained from their medical files. Two neuroradiologists independently re-reviewed all neuroimages, and the average of their assessments was compared with the initial neuroimaging reports; an additional review was done to analyze inter- and intraclass correlation.

RESULTS

The initial neuroimaging reports showed under-reporting of findings, with only 26 of 48 (54.1%) patients identified with abnormal reports. After revision, the proportion of the reported findings increased to 44 of 48 (91.6%). Distention of the perioptic space was the most commonly reported finding after revision (36.5 of 48; 76%). Flattening of the posterior globe and empty sella were initially under-reported but improved after revision. Moreover, several findings suggestive of increased intracranial pressure not mandated by Friedman criteria were identified, such as narrowing of the Meckel cave, posterior displacement of the pituitary stalk, and narrowing of the cavernous sinus. Analysis of associations between neuroimaging findings and demographic and clinical characteristics yielded no statistically significant results. The inter- and intraclass correlation results demonstrated a significant agreement between raters and within each rater's assessment (P < 0.05).

CONCLUSIONS

This study highlights the impact of image revision in enhancing PTCS diagnosis. Intra- and interclass correlations underscore the reliability of the review process, emphasizing the importance of meticulous image analysis in clinical practice.

Influence of sex and disease etiology on the development of papilledema and optic nerve sheath extension in the setting of intracranial pressure elevation in children

Introduction

Dilatation of the optic nerve sheath diameter and swelling of the optic disc are known phenomena associated with intracranial pressure elevation.

Research question

Do sex and disease etiology have an impact on the development of optic disc elevation and optic nerve sheath extension in children in the setting of ICP elevation? Fundoscopic papilledema and point-of-care-ultrasound techniques-optic nerve sheath diameter (US-ONSD) and optic disc elevation (US-ODE) - were compared in this regard.

Material and methods

72 children were included in this prospective study; 50 with proven pathology (e.g. pseudotumor cerebri, tumor), 22 with pathology excluded. Bilateral US-ONSD and US-ODE were quantified by US using a 12-MHz-linear-array-transducer. This was compared with fundoscopic optic disc findings and in 28 patients with invasive ICP values, stratified for sex and etiology.

Results

In patients with proven disease, significant more girls (69%) had fundoscopic papilledema compared with boys (37%, p < 0.05). Girls had also larger US-ODE values (0.86 ± 0.36 mm vs. 0.65 ± 0.40 mm in boys). 80% of tumor patients had initial papilledema (100% girls, 79% boys), compared with 50% in pseudotumor cerebri (PTC) (83% girls, 30% boys). US-ONSD had no sex- and no etiology-specificity.

Discussion and conclusion

Presence of papilledema appears to be influenced by sex and etiology, whereas US-ONSD is not. Girls seem more likely to develop papilledema under similar conditions. Male sex and PTC appear as risk factors for being undetected by fundoscopic findings. US-ONSD and US-ODE seem useful tools to identify pathologies with potentially increased ICP requiring treatment in children regardless of sex and etiology.

Pseudotumor cerebri syndrome in children: Clinical characteristic and re-classification

AIM

To describe the clinical characteristics of children with pseudotumor cerebri syndrome (PTCS) who were diagnosed according to the modified Dandy criteria and to reclassify them according to the newly proposed diagnostic criteria by Freidman.

METHODOLOGY

This retrospective study included the period from January 2016-to July 2021.

RESULTS

50 patients were included; 34 males and 16 females with a male to female ratio of 2.1:1. The average age at onset of symptoms was 8 years. Obesity was noticed in 6 (12%) patients; 34 (68%) had symptoms upon presentation. The most common presenting symptom was headache (28 patients; 56%), papilledema was present in 33 (66%) patients. Most patients (37; 74%) had an initial cerebrospinal fluid (CSF) pressure ≥280 mmH₂O. At last follow-up, papilledema resolved in 11/32 (34.3%) patients, and headache resolved in 17/23 (74%) patients. 22/50 (44%) patients fulfilled the definite criteria proposed by Freidman, 11/50 (22%) fulfilled the probable, 10/50 (20%) were categorized as possible, and 7 (14%) patients were categorized as unmet.

CONCLUSION

PTCS is a chronic condition. Managing patients who do not have papilledema or who do not meet the newly proposed higher CSF pressure is challenging. Although, applying the newly proposed criteria captured most of our patients, however, around one quarter were managed based on clinical experience. This study indicates a strong need for future guidelines tailored specifically for children, taking into consideration that the cut-off point of CSF pressure might not be similar for all populations.

Non-Invasive Intracranial Pressure Monitoring and Its Applicability in Spaceflight

INTRODUCTION: Neuro-ophthalmic findings collectively defined as Spaceflight-Associated Neuro-ocular Syndrome (SANS) are one of the leading health priorities in astronauts engaging in long duration spaceflight or prolonged microgravity exposure. Though multifactorial in etiology, similarities to terrestrial idiopathic intracranial hypertension (IIH) suggest these changes may result from an increase or impairing in intracranial pressure (ICP). Finding a portable, accessible, and reliable method of monitoring ICP is, therefore, crucial in long duration spaceflight. A review of recent literature was conducted on the biomedical literature search engine PubMed using the search term “non-invasive intracranial pressure”. Studies investigating accuracy of noninvasive and portable methods were assessed. The search retrieved different methods that were subsequently grouped by approach and technique. The majority of publications included the use of ultrasound-based methods with variable accuracies. One of which, noninvasive ICP estimation by optical nerve sheath diameter measurement (nICP_ONSD), presented the highest statistical correlation and prediction values to invasive ICP, with area under the curve (AUC) ranging from 0.75 to 0.964. One study even considers a combination of ONSD with transcranial Doppler (TCD) for an even higher performance. Other methods, such as near-infrared spectroscopy (NIRS), show positive and promising results [good statistical correlation with invasive techniques when measuring cerebral perfusion pressure (CPP): r = 0.83]. However, for its accessibility, portability, and accuracy, ONSD seems to present itself as the up to date, most reliable, noninvasive ICP surrogate and a valuable spaceflight asset.Félix H, Santos Oliveira E. Non-invasive intracranial pressure monitoring and its applicability in spaceflight. Aerosp Med Hum Perform. 2022; 93(6):517–531.

How do presentation age and CSF opening pressure level affect long-term prognosis of pseudotumor cerebri syndrome in children? Experience of a single tertiary clinic

BACKGROUND

Diagnosis and treatment of pseudotumor cerebri syndrome in children is still a challenge for clinicians. The aim of this study is to reveal the influence of presentation age and CSF opening pressure on long-term prognosis of pseudotumor cerebri and share our clinical data of the very young age (≤ 5-year) group.

METHOD

This retrospective study includes the patients followed by the Marmara University Pediatric Neurology Clinic between years 2012 and 2020 diagnosed with definite, probable, or suggestive pseudotumor cerebri syndrome according to modified Friedman criteria. Patients were classified into three groups according to presentation age: group 1: ≤ 5 years old; group 2: 6-10 years; and group 3 > 10 years old. CSF opening pressure was also categorized into three groups as CSF < 20 cmH20; CSF 20-30 cmH20; and CSF > 30 cmH20.

RESULTS

One hundred three patients, 62.1% female (n = 64), were enrolled in the study. Group 1 consisted of 16 patients (60% male), group 2 consisted of 30 patients (63.3% female), and group 3 consisted of 57 patients (66.7% female). The mean CSF opening pressure did not differ between the three age groups in our study (p > 0.05). Treatment response was not correlated with CSF opening pressure. Papilledema presence and level of CSF opening pressure were independent of age (p > 0.05).

CONCLUSIONS

Age at presentation and CSF opening pressure at diagnosis are not any predictive factors that influence long-term prognosis of pseudotumor cerebri syndrome in children. Evaluation and follow-up of children should be done in personalized approach.

Pseudotumor Cerebri Syndrome: From Childhood to Adulthood Risk Factors and Clinical Presentation

INTRODUCTION

Although considered uncommon, pseudotumor cerebri syndrome (PTC) is a significant cause of headache among children and adults. However, the presenting symptoms may be different among diverse age groups. In the present study, we compared the risk factors and clinical presentation of PTC across life-from childhood to adulthood.

METHODS

A retrospective survey of PTC patients aged 7 years or older between 2011 and 2013 was carried out. Pooled analyses were performed comparing characteristics from our data with those of published data subdivided into 3 age groups: pre-young children, adolescents, and adults.

RESULTS

Our cohort consisted of 72 patients: 32 children (10 pre-young children, 22 adolescents) and 40 adults. Within the pre-young children age group: 20% were females versus 82% in the adolescent age group and 85% of the adult age group. Obesity was found in 10% of the young children group, 64% of the adolescents, and 80% of the adults. Headache was reported in 70% young children, 82% adolescents, and 83% adults. Pooled analysis of 1499 patients showed that young children with PTC tend to complain less about headache compared with older ones. Vomiting and visual impairment were most common among adolescents, and dizziness and tinnitus were most common in adults.

CONCLUSION

PTC has different risk factors and clinical presentation throughout life. In young children, there is no gender preference and most patients are not obese. Risk factors in adolescents resemble those of adults.

Asymptomatic Versus Symptomatic Idiopathic Intracranial Hypertension in Children

BACKGROUND

Idiopathic intracranial hypertension is a rare neurologic condition characterized by elevated intracranial pressure with normal cerebrospinal fluid analysis and neuroimaging. A subset of pediatric idiopathic intracranial hypertension patients are coincidentally found to have papilledema and elevated intracranial pressure without symptoms (eg, headache, visual blurring, tinnitus). This study aims to investigate the features of asymptomatic pediatric idiopathic intracranial hypertension.

METHODS

Retrospective case-control study of patients aged 0 to 18 years who received idiopathic intracranial hypertension diagnosis from 2005 to 2016. Subjects were included if they met established diagnostic criteria for idiopathic intracranial hypertension diagnosis. Subjects were classified as symptomatic if they presented with 1 symptom related to elevated intracranial pressure, and asymptomatic if no symptoms were present. Statistical analysis was performed to compare the 2 groups.

RESULTS

12 (22.6%) of 53 pediatric idiopathic intracranial hypertension subjects were asymptomatic. Compared to symptomatic idiopathic intracranial hypertension, asymptomatic idiopathic intracranial hypertension had younger age of onset, lower initial opening pressure on lumbar puncture, lower optic nerve edema grades bilaterally, lower likelihood of globe flattening on magnetic resonance imaging (MRI), and smaller required dose of acetazolamide for resolution of papilledema (all P < .05).

CONCLUSION

Asymptomatic idiopathic intracranial hypertension is common among pediatric patients with papilledema and is an important disease entity that requires special clinical management. It may exist as a milder version of idiopathic intracranial hypertension that occurs in younger children, or as a precursor state that later evolves into symptomatic disease.

Dural sinus collapsibility, idiopathic intracranial hypertension, and the pathogenesis of chronic migraine

Available evidences suggest that a number of known assumption on idiopathic intracranial hypertension (IIH) with or without papilledema might be discussed. These include (1) the primary pathogenetic role of an excessive dural sinus collapsibility in IIH, allowing a new relatively stable intracranial fluids pressure balance at higher values; (2) the non-mandatory role of papilledema for a definite diagnosis; (3) the possibly much higher prevalence of IIH without papilledema than currently considered; (4) the crucial role of the cerebral compliance exhaustion that precede the raise in intracranial pressure and that may already be pathologic in cases showing a moderately elevated opening pressure; (5) the role as "intracranial pressure sensor" played by the trigeminovascular innervation of dural sinuses and cortical bridge veins, which could represent a major source of CGRP and may explain the high comorbidity and the emerging causative link between IIHWOP and chronic migraine (CM). Accordingly, the control of intracranial pressure is to be considered a promising new therapeutic target in CM.

Pseudotumor Cerebri Syndrome in Children

PURPOSE OF REVIEW

Pseudotumor cerebri syndrome (PTCS) may affect both children and adults; however, the risk factors and clinical presentation vary greatly between these populations. This review aims to highlight the entity of PTCS in children and the unique considerations in this population; review the epidemiology and demographics; discuss the clinical presentation, revised diagnostic criteria, and approach to evaluation; review management strategies; and discuss the prognosis and long-term outcomes in children with PTCS.

RECENT FINDINGS

Clinical presentation can be variable in children and may be less obvious than in their adult counterparts. Papilledema can also be challenging to diagnose in this population. The upper limits for opening pressure on lumbar puncture differ in children, with a cut-off of 25 cm H20 (or 28 cm H2O in a sedated or obese child). Morbidity related to visual loss, pain and reduced quality of life lends urgency towards accurately identifying, evaluating and managing children with PTCS. There are no randomised controlled studies to allow for evidence-based recommendations for the management of PTCS in children. Further studies are needed to clarify and consolidate management approaches in this population.

Comparing invasive with MRI-derived intracranial pressure measurements in healthy elderly and brain trauma cases: A pilot study

BACKGROUND

Intracranial pressure (ICP) is an important physiological parameter in several neurological disorders. Considerable effort has been made to measure ICP noninvasively. MR-based ICP (MR-ICP) is a nonempirical method based on principles of cerebrospinal fluid (CSF) physiology, where ICP is obtained from measurements of blood and CSF flows to and from the cranium during the cardiac cycle.

PURPOSE

To compare MR-ICP with invasive ICP measurements obtained using lumbar puncture (LP) or external ventricular drainage (EVD).

STUDY TYPE

Prospective, cross-sectional, observational study.

SUBJECTS

Ten cognitively healthy elderly subjects (age 69.6 ± 6.6 years; seven females) and six brain trauma patients (age 36.8 ± 19.7 years; two females).

FIELD STRENGTH

Velocity encoding cine phase-contrast at 1.5 T and 3 T.

ASSESSMENT

MR-ICP and craniospinal compliance distribution were estimated from arterial inflow and venous outflow to and from cranium, and craniospinal CSF flow at the upper cervical region, measured using cine phase contrast MRI. LP (done 177 ± 163 days after scan) and EVD measurements (at the time of scan) were performed in lateral recumbent and supine positions, respectively.

STATISTICAL TESTS

Linear regression was used to assess the relationships of MR-ICP with invasive ICP, and the dependency of these measurements on age, weight, height, and BMI. A Shapiro-Wilks test and Bland-Altman plot were respectively used to evaluate the normality and agreement between these two pressure distributions. Student's t-test was used throughout the analysis to compare differences between the EVD and LP cohorts.

RESULTS

In the combined cohort, MR-ICP and invasive ICP were positively correlated (r = 0.95, P < 0.001), with invasive ICP being higher than MR-ICP by 2.2 mmHg on average. In the healthy cohort, the cranial contribution to total craniospinal compliance was negatively correlated with MR-ICP (r = -0.90, P < 0.001).

DATA CONCLUSION

MR-ICP provides a reliable estimate of ICP, with 14 out of 16 datapoints within the clinically acceptable error. Craniospinal compliance distribution plays a role in modulating ICP in supine position.

LEVEL OF EVIDENCE

3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:975-981.

Idiopathic intracranial hypertension: Proposal of a stratification strategy for monitoring risk of disease progression

OBJECTIVES

A general consensus based on a multidisciplinary perspective involving an international panel was recently developed for management of patients with idiopathic intracranial hypertension (IIH). In this paper, the authors sought to develop further on the aspect of this consensus that concerns monitoring progression of the disease.

PATIENTS AND METHODS

A systematic literature review of previous publications on monitoring disease progression in IIH and a meta-analysis to examine efficacy of method of monitoring employed in each study. The authors present a brief descriptive analysis of challenges with monitoring progression of the disease and propose a risk stratification to aid monitoring.

RESULTS

Of a total of 382 publications identified from the literature search, only 8 studies (144 patients) satisfied inclusion criteria and were included for analysis. Among these, 3 were based on ICP monitoring while the remaining 5 focused on ophthamological evaluation. Interestingly, there were neither any studies on monitoring with progression of clinical features nor any study on monitoring with symptomatology associated with IIH among the selected studies.

CONCLUSION

There is a paucity of studies in the literature on methods of monitoring disease progression in IIH. Though close attention to adequate evaluation and proper care of patients with IIH remains the key in managing this problem, this proposed risk stratification will be an objective tool and useful guide to better monitor these patients according to their extent of risk from the disease and possibly for planning treatment and intervention.

Intracranial hypertension: a current review

PURPOSE OF REVIEW

To provide a current review of recent publications with regards to intracranial hypertension.

RECENT FINDINGS

Attempts were made to provide pediatric data; however, the recent completion of the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT) has provided a wealth of data with regards to adult intracranial hypertension.The pediatric incidence of intracranial hypertension ranges between 0.63 and 0.71 per 100 000 children. A majority of pediatric cases responded to acetazolamide, with resolution of headache averaging 3.8 weeks. Most patients require less than 1 year of treatment with male sex, older age at diagnosis, primary intracranial hypertension, and lack of headache being predictors of good response. Fluorescein angiography has the highest accuracy in distinguishing true papilledema from pseudopapilledema. The IIHTT found Frisen grade of papilledema was within 1 grade in 92.8% of patients. Monitoring of potassium levels is not required and aplastic anemia was not seen in patients taking acetazolamide.

SUMMARY

Although the newer pediatric studies report incidence rates in pediatric intracranial hypertension are lower than seen in adults, intracranial hypertension is still a concern in pediatrics. There has been a wealth of information with regards to symptomatology, treatment, and outcomes from the IIHTT that will hopefully assist with management in the pediatric population.

Pediatric Intracranial Hypertension: a Current Literature Review

PURPOSE OF REVIEW

The purpose of this review is to provide an update on pediatric intracranial hypertension.

RECENT FINDINGS

The annual pediatric incidence is estimated at 0.63 per 100,000 in the USA and 0.71 per 100,000 in Britain. The Idiopathic Intracranial Hypertension Treatment Trial found improvement in visual fields, optical coherence tomography, Frisen grade, and quality of life with acetazolamide compared to placebo in adult patients, and these findings have been translated to the pediatric population. Pediatric intracranial hypertension is a disorder that if left untreated can lead to poor quality of life and morbidity. There are no current treatment studies in pediatrics, but adult data suggests acetazolamide remains an acceptable first-line medication.