Epidemiology and risk factors for idiopathic intracranial hypertension

Age-related variations in opening pressure in lumbar puncture: Implications for its interpretation in children

INTRODUCTION

Opening pressure in lumbar puncture (LP) is an important parameter in the diagnosis of various neurological diseases. In children pressures may vary according to age. This study aimed to analyze the variation of opening pressure in LP according to age in children.

METHODS

All LPs performed between February 2017 and March 2023 were analyzed. Patients with modifying factors for opening pressure were excluded. Descriptive analysis was conducted, along with a comparison of means and medians, local regression, and quantile regression. To identify the most relevant cutoff points, graphical analyses were employed.

RESULTS

The median opening pressure was 21.0 cm H2O, with a 10th percentile (P10) of 10 and a 90th percentile (P90) of 32. An increase in opening pressure with age was found. Graphical analysis revealed a significant cutoff point at 96 months. The median opening pressure from 1 to 96 months of age was 19.2 cm H2O, with a P10 of 8 and a P90 of 28.9. For children older than 96 months, the median was 22 cm H2O, with a P10 of 11.8 and a P90 of 35.

CONCLUSION

Opening pressures in children vary with age, with no differences related to sex. Graphical analysis indicates that 96 months of age is an important cutoff point. Above this age, standard values could be used, up to 96 months of age, however, it is necessary to conduct studies for reference values. Opening pressure alone is not sufficient for the diagnosis of intracranial hypertension in children.

Correlation between lumbar puncture opening pressure and venous sinus pressure gradient in idiopathic intracranial hypertension (IIH)

BackgroundVenous hypertension has become a recognized condition associated with idiopathic intracranial hypertension (IIH). Thresholds for dural venous sinus stenting (VSS) remain a topic of debate.MethodsIn 50 IIH patients, the lumbar puncture opening pressure (LPOP) and the pressure gradient across the dominant venous sinus were correlated. Clinical variables were compared; linear regression models were created. Venous stenting was performed in select patients with bilateral venous sinus stenosis, papilledema, LPOP >25 cmH2O, and a venous pressure gradient >10 mmHg.ResultsTwenty-nine patients were selected for venous sinus stenting (VSS); 21 patients did not meet the criteria for stenting despite some IIH symptoms. After stent implantation, patients experienced improvement in their symptoms.Across all 50 patients, there was a significant correlation between LPOP and the pressure gradient across the stenosis of the dominant venous sinus (r = 0.76, 95% confidence interval [0.53-1.00], P < .001).ConclusionsAn increased venous pressure gradient across the dominant sigmoid/transverse junction was strongly associated with an increased lumbar puncture opening pressure in IIH patients. A gradient increase of 1 mmHg correlated with an increase of LPOP by 0.85 cmH2O. Patients with higher baseline venous pressure gradients may therefore benefit the most from venous stenting.

Evaluation of predictive factors of idiopathic intracranial hypertension in different clinics

PURPOSE

Idiopathic Intracranial Hypertension (IIH) is marked by elevated intracranial pressure without an identifiable cause. This study aimed to compare predictive factors between two IIH groups: those experiencing remission (single attack) and those developing migrainous headaches, in order to identify factors influencing the disease's progression.

METHODS

This retrospective study was conducted after obtaining ethics committee approval. It involved 118 patients diagnosed with IIH who were followed up in the Neuro-ophthalmology outpatient clinic between 2011 and 2023. Data on demographics, clinical history, comorbidities, habits, neurologic and neuro-ophthalmologic findings, cranial imaging features, lumbar puncture opening pressure, and current medical treatments were collected to assess the clinical course and predictive factors. The analyzed parameters were compared between two subgroups: one experiencing remission (single attack) and the other developing migrainous headaches. Statistically significant parameters were subjected to univariate and multivariate analysis.

RESULTS

Of the 118 patients, 87 (73.7 %) were in the single-attack group, while 31 (26.3 %) were in the migrainous headache group. Key predictive factors identified between the groups were the presence of allodynia (p < 0.001), neck and back pain (p = 0.042), BMI > 27.8 kg/m² (p = 0.002), and a history of migraine (p < 0.001).

CONCLUSIONS

Allodynia, neck and back pain, a history of migraine, and a BMI > 27.8 kg/m² were found to be predictive factors for the development of migrainous headaches in IIH patients. This is the first study in the literature to compare these two patient groups and identify the factors that contribute to the development of migrainous headaches.

Idiopathic intracranial hypertension: Imaging and clinical fundamentals

Neuroimaging is a paramount element for the diagnosis of idiopathic intracranial hypertension, a condition characterized by signs and symptoms of raised intracranial pressure without the identification of a mass or hydrocephalus being recognized. The primary purpose of this review is to deliver an overview of the spectrum and the specific role of the various imaging findings associated with the condition while providing imaging examples and educational concepts. Clinical perspectives and insights into the disease, including treatment options, will also be discussed.

Spontaneous cerebrospinal fluid rhinorrhea as a primary presentation of idiopathic intracranial hypertension, management strategies, and clinical outcome

Background

Causes of cerebrospinal fluid (CSF) rhinorrhea could be divided into primary (spontaneous) and secondary (head trauma and iatrogenic). Idiopathic intracranial hypertension (IIH) has emerged as a cause for spontaneous CSF rhinorrhea but is still underestimated, may be overlooked and needs special consideration in management. The objective of this study is to demonstrate spontaneous CSF rhinorrhea as the primary presentation of IIH and explore the algorithm of management.

Methods

All patients with spontaneous (primary) CSF rhinorrhea were included with complete clinical and radiological assessment. We performed lumbar puncture and CSF pressure measurements in the lateral decubitus position for all included patients to detect those with intracranial hypertension. A pressure of 20 cmH2O in cases of CSF rhinorrhea is considered a cutoff for diagnosing raised intracranial pressure. When intracranial hypertension was diagnosed, patients were subjected immediately to lumboperitoneal shunt. If CSF leakage stopped after shunt insertion, we would not perform skull base repair, and the patient was sent for follow-up. However, if CSF leakage did not stop after shunt insertion despite normalization of intracranial tension or recurrence of CSF rhinorrhea despite shunt patency or there was intracranial pneumocephalus, skull base repair would be performed.

Results

During the period of the study, 293 cases of CSF rhinorrhea were seen. Only 42 (14.3%) patients were diagnosed with spontaneous CSF rhinorrhea, and the remaining were posttraumatic. Thirty-seven patients (88.1%) of 42 patients revealed high CSF pressure readings. All 37 patients received lumboperitoneal shunt followed by CSF rhinorrhea stoppage. Later, during follow-up, 7 patients developed recurrence of leakage; 3 of them revealed shunt obstruction, and rhinorrhea improved after shunt revision. The other 4 patients revealed patent shunt and needed skull base repair.

Conclusion

Spontaneous CSF rhinorrhea is considered secondary to IIH until proven otherwise. Initial placement of lumboperitoneal shunt may provide an effective alternative to skull base repair for the treatment of patients with IIH presenting with CSF rhinorrhea.

Long-Term Outcomes of Sigmoid Sinus Wall Reconstruction for Pulsatile Tinnitus Due to Sigmoid Sinus Wall Anomalies

OBJECTIVE

To assess the long-term outcomes of sigmoid sinus wall reconstruction (SSWR) in patients with pulsatile tinnitus (PT) with sigmoid sinus wall anomalies (SSWAs).

STUDY DESIGN

Single-center retrospective review.

SETTING

Tertiary referral center.

PATIENTS

Patients who underwent SSWR for PT with SSWAs more than 5 years prior to study initiation.

INTERVENTIONS

Therapeutic-all patients underwent sinus wall reconstruction for pulsatile tinnitus with sigmoid sinus anomalies.

MAIN OUTCOME MEASURES

The primary outcomes were complete or partial resolution of PT lasting at least 5 years postoperatively and short-term relief from PT after surgery with long-term recurrence as determined by a self-assessment questionnaire and corroborated by the medical record.

RESULTS

Thirty-five patients (37 ears) out of 58 eligible patients 5 years postoperatively from SSWR completed the survey. Short-term and long-term success rates of SSWR are 97.3% (36/37 ears) and 83.8% (31/37 ears), respectively. Of the patients, 13.5% (5/37 ears) experienced recurrence of PT on the same side following initial resolution. Of our patients, 8.6% had a confirmed diagnosis of idiopathic intracranial hypertension (IIH) after a follow-up period of more than 5 years.

CONCLUSIONS

Sinus wall reconstruction is an effective procedure for long-term control of PT in patients with SSWAs, with an acceptable safety profile and very low additional risk of exacerbating or provoking complications associated with IIH.

Clinical Characteristics of Idiopathic Intracranial Hypertension in Older Adults

BACKGROUND

Idiopathic intracranial hypertension (IIH) is a condition that classically affects obese women of child-bearing age. However, it is sometimes encountered in older patients. The purpose of this study was to help clinicians better understand how this disease can present differently in these age groups.

METHODS

This is a retrospective chart review from a single academic center of baseline characteristics of adult patients diagnosed with IIH based on the modified Dandy criteria. The patients were divided into 2 groups: (1) those 18-44 years old and (2) those older than 45 years at diagnosis.

RESULTS

One hundred sixty-seven patients were identified; 135 in the younger group and 32 in the older group. The younger group had a higher rate of headaches (90% vs 63%, P = 0.0004), higher body mass index (38.9 vs 36.1, P = 0.046), higher opening pressure (38 vs 31 cm H 2 O, P = 0.005), and thicker peripapillary retinal nerve fiber layer average thickness (right eye 178 vs 131 μm, P = 0.02; left eye 184 vs 136 μm, P = 0.045). The older group had higher rates of empty sella (90% vs 62%, P = 0.0039). In addition in the younger group, there was a trend toward higher rates of pulsatile tinnitus (63% vs 45%, P = 0.08), transient visual obscurations (50% vs 32%, P = 0.07), and lower rates of spontaneous cerebrospinal fluid leak (4% vs 13%, P = 0.08). Sex, rates of obesity, other MRI findings typical of elevated intracranial pressure, frequency and Frisen grading of papilledema, and visual field loss were not statistically different between the groups.

CONCLUSIONS

The older age group had milder signs and symptoms of IIH and a higher prevalence of empty sella than the younger group, but otherwise had typical characteristics. These findings suggest that IIH in the older age group may represent milder chronic disease that was previously undiagnosed.

Idiopathic intracranial hypertension following childbirth: a case report and management strategies

Introduction

A postpartum headache, also known as pseudotumor cerebri, is defined as a headache and shoulder or neck pain that occur in the first 6 weeks following childbirth. Common causes of headaches during puerperium include pre-eclampsia, subarachnoid hemorrhage, cerebral venous thrombosis, meningitis, brain tumors, cerebrovascular diseases, and posterior reversible encephalopathy syndrome. Pseudotumor cerebri is an extremely rare cause of postpartum severe headache with visual disturbance with or without papilledema.

Case presentation

Here, the authors present a 32-year-old postpartum female patient who presented with a severe headache and visual disturbance for 10 days. Neurological examination did not show any focal or lateralizing deficit. However, a fundus examination showed severe bilateral papilledema. A contrast-enhanced brain MRI did not reveal a space-occupying mass lesion. MRV excluded venous occlusion. A lumbar puncture demonstrated a high opening pressure of 75 cmH2O with a normal cell count and protein and glucose levels. The patient was diagnosed with idiopathic intracranial hypertension. After 8 weeks of treatment with diazomid and topiramate, the patient improved clinically, and her papilledema regressed.

Clinical discussion

The occurrence of IIH is very rare among postpartum females. To our knowledge, very few cases of postpartum IIH have been reported in the medical literature. Although rare, patients with postpartum headache with visual disturbances should have a fundoscopic examination. The patient was diagnosed and managed in time, which led to significant clinical improvement and salvage of her vision.

Conclusion

As described in this case, idiopathic intracranial hypertension can cause severe headaches with and without visual disturbance during the postpartum period (despite being rare in this period), so it should be considered in the differential diagnosis.

Beyond the Surface: A Unique Presentation of Acute Promyelocytic Leukemia as Idiopathic Intracranial Hypertension: A Case Report

BACKGROUND

Acute promyelocytic leukemia (APL) is a subtype of acute myeloid leukemia defined by a fusion gene transcript called PML::RARA. Pseudotumor cerebri (PTC) is characterized by elevated intracranial pressure (ICP) and presents with pulsatile tinnitus, headaches, and visual disturbances. Pseudotumor cerebri has been observed in some patients undergoing long-term ATRA therapy. While both APL and PTC have been individually described in the literature, their coexistence in a single patient, especially with PTC being the first clinical manifestation of APL, is an exceptionally rare occurrence, making this case particularly unique and warranting further investigation.

CASE PRESENTATION

We present the case of a 30-year-old woman who initially presented with symptoms suggestive of PTC. The diagnosis of PTC was confirmed through a lumbar puncture. However, further investigations revealed that the patient had APL, which is typically sensitive to treatment with all-trans-retinoic acid (ATRA). To our knowledge, the association between APL and PTC as the first clinical manifestation of APL in adult patients has not been previously reported in the literature, further highlighting the exceptional rarity of this case.

CONCLUSIONS

This case underscores the importance of considering underlying systemic diseases in patients presenting with PTC, as it may represent an exceptionally rare initial manifestation of a rare underlying malignancy such as APL. The coexistence of APL and PTC in this patient highlights the need for a comprehensive evaluation and management approach to promptly diagnose and treat coexisting conditions. Healthcare providers must be aware of this association and consider the possibility of APL when evaluating patients with PTC symptoms. Such awareness can prompt timely recognition and appropriate management, thereby improving patient outcomes and preventing potential delays in diagnosis and treatment.

A systematic review of surgical and interventional radiology procedures for pediatric idiopathic intracranial hypertension

Background

Idiopathic intracranial hypertension (IIH) is defined as elevated intracranial pressure and consequent symptoms (mainly headache and visual deterioration) occurring in the absence of secondary causes. Surgical and interventional radiology procedures should be considered for refractory IIH and mainly include cerebrospinal fluid (CSF) diversion techniques, optic nerve sheath fenestration (ONSF), and venous sinus stenting (VSS). Our study aims to review the current literature on the application of these techniques in clinical practice.

Methods

A systematic literature review on the surgical and interventional radiology treatment of IIH was conducted, focusing on ONSF, VSS, and CSF diversion techniques. According to PRISMA guidelines, all reports published in PubMed in the last 30 years (1993-2023) were considered, and among 722 papers, 48 were included in the present study, resulting in a total study population of 454 children or adolescents (11 months-17 years old).

Results

Among 454 patients, 193 underwent an invasive approach, divided into CSF diversion (115/193), ONSF (65/193), VSS (11/193), cranial subtemporal decompression (8/193), and internal cranial expansion (9/193). Sixteen of the 193 patients (8%) required reintervention due to relapsing symptoms or surgical complications, particularly those who underwent CSF diversion. Furthermore, 9/115 required shunt revision due to shunt obstruction or malfunction. We extracted data on the outcome of each procedure: of the 193 patients, 71 experienced a positive outcome with symptom resolution or improvement, while 27 demonstrated a negative outcome.

Discussion and conclusions

Severe and refractory cases of IIH are eligible for invasive treatments. CSF diversion is the most frequently used technique, despite its high failure risk and need for reintervention. ONSF has shown good results in terms of outcome and safety, particularly in children with visual symptoms. VSS is the most recent approach, indicated in children with stenosis of the venous sinus. In our study population, VSS demonstrated good results in terms of symptom resolution and need for reintervention, but its use remains limited to a few centers.

Systematic Review Registration

https://www.crd.york.ac.uk/, PROSPERO (CRD42024504244).

Intermittent spontaneous CSF rhinorrhea exacerbated by hormonal fluctuations associated with menstrual cycles

This case underscores the importance of recognizing the potential link between hormonal fluctuations during the menstrual cycle and idiopathic intracranial hypertension (IIH), which could lead to spontaneous cerebrospinal fluid (CSF) rhinorrhea. Eliciting a history of intermittent clear rhinorrhea with the onset of menstrual cycle if presenting with menstrual migraines could allow for a more prompt diagnosis and treatment of IIH and CSF leak. Early diagnosis and intervention are crucial to prevent serious complications.

Idiopathic intracranial hypertension and obstetric and neonatal outcomes: A 1:20 matched study from a population database

OBJECTIVE

Idiopathic intracranial hypertension (IIH), also known as pseudotumor cerebri, is a common pathology in reproductive-aged women, although data regarding pregnancy outcomes are scarce. In the present study, we aimed to compare pregnancy and perinatal outcomes between women who suffered from IIH to those who did not.

METHODS

A retrospective cohort study using the Healthcare Cost and Utilization Project, Nationwide Inpatient Sample. All pregnant women who delivered or had a maternal death in the US (2004-2014) were included. Women with an ICD-9 diagnosis of IIH before or during pregnancy were matched to controls without IIH according to age, race, insurance type, and income quartile, in a 1:20 ratio. Pregnancy, delivery, and neonatal outcomes were compared between the two groups.

RESULTS

Overall, 9 096 788 deliveries were identified. Of these, 1454 women (0.016%) had a diagnosis of IIH (study group) and were compared to 29 080 women without IIH (control group). Women with IIH, compared to those without, were more likely to be obese (body mass index >30 kg/m2) and suffer from pregestational diabetes mellitus and chronic hypertension (P < 0.001, all). After adjusting for confounders, patients in the IIH group, compared to those without, had a higher rate of pregnancy-induced hypertension (aOR 1.82, 95% CI: 1.57-2.1, P < 0.001), pre-eclampsia (aOR 1.98, 95% CI: 1.61-2.45, P < 0.001), preterm delivery (aOR 1.88, 95% CI: 1.59-2.23, P < 0.001), CD (aOR 2.41, 95% CI: 2.12-2.73, P < 0.001), wound complications (aOR 3.2, 95% CI: 1.89-5.42, P < 0.001), and congenital anomalies (aOR 2.18, 95% CI: 1.4-3.4, P < 0.001).

CONCLUSION

Women with IIH had a higher incidence of obstetrical complications, including preterm deliveries, hypertensive disorders of pregnancy, and congenital anomalies.

Progress and recognition of idiopathic intracranial hypertension: A narrative review

BACKGROUND

Idiopathic intracranial hypertension (IIH) mainly affects obese young women, causing elevated intracranial pressure, headaches, and papilledema, risking vision loss and severe headaches. Despite weight loss as the primary treatment, the underlying mechanisms remain unclear. Recent research explores novel therapeutic targets.

AIMS

This review aimed to provide a comprehensive understanding of IIH's pathophysiology and clinical features to inform pathogenesis and improve treatment strategies.

METHODS

Recent publications on IIH were searched and summarized using PubMed, Web of Science, and MEDLINE.

RESULTS

The review highlights potential pathomechanisms and therapeutic advances in IIH.

CONCLUSION

IIH incidence is rising, with growing evidence linking it to metabolic and hormonal disturbances. Early diagnosis and treatment remain challenging.

The diagnostic value of MRI findings in pediatric idiopathic intracranial hypertension: a case-control study

BACKGROUND

Idiopathic intracranial hypertension (IIH) is a rare medical condition in children. Based on the different radiological findings reported in various studies in pediatric IIH, this study was conducted to determine the diagnostic value of MRI findings in diagnosing IIH in children.

METHODS

In this retrospective study, the medical records of all children aged 1 to 18 years who visited Ghaem Hospital in Mashhad, Iran, between 2012 and 2022 and were diagnosed with IIH were gathered. Forty-nine cases of children with IIH and 48 control cases of children with the first unprovoked seizure with no indications of increased intracranial pressure for comparison were selected. Patient demographic information and MRI findings were extracted. The comparison between different MRI findings in the case and control groups was conducted using statistical tests.

RESULTS

In the case group, the mean diameter of the subarachnoid space expansion around the optic nerve was 5.96 ± 1.21, compared to 4.79 ± 0.33 in the control group, with statistically significant difference (P < 0.001). All the patients with flattening of the posterior globe or transverse sinus stenosis were in the case group, and the frequency of these findings in the case group was significantly higher than in the control group (P < 0.001). The majority of patients (95.5%) classified under category 3 and 4 of empty sella were part of the case group, and the statistical test results indicated a significant difference between the two groups (P < 0.001). The optic nerve sheath diameter cut-off of 5.35 mm, when used for expansion of the subarachnoid space around the optic nerve, with a sensitivity of 82% and a specificity of 100% in diagnosing IIH.

CONCLUSION

The most reliable diagnostic indicators for diagnosing IIH in children are perioptic subarachnoid space expansion with high sensitivity, and posterior globe flattening and transverse sinus stenosis with high specificity.

Collapse or distention of the perioptic space in children - What does it mean to pediatric radiologists? Comprehensive review of perioptic space evaluation

The perioptic space comprises the subarachnoid space [SAS] of the optic nerve communicating with the SAS of the central nervous system. Pressure variations in the SAS of the central nervous system can be transmitted to the optic papilla through the perioptic space. Variations in the diameter of the perioptic space serve as an important indicator for select intracranial pathologies in the pediatric population. Though the perioptic space can be evaluated using various imaging modalities, MRI is considered highly effective due to its superior soft tissue resolution. With advancement in MR imaging techniques, high-resolution images of the orbits can provide improved visualization of the perioptic space. It is imperative for the pediatric radiologist to routinely assess the perioptic space on brain and orbit MR imaging, as it can prompt exploration for additional features associated with select intracranial pathologies, thus improving diagnostic accuracy. This article reviews basic anatomy of the perioptic space, current understanding of the CSF dynamics between the perioptic space and central nervous system SAS, various imaging modalities utilized in the assessment of the perioptic space, MRI sequences and the optimal parameters of specific sequences, normal appearance of the perioptic space on MR imaging, and various common pediatric pathologies which cause alteration in the perioptic space.

Probability density and information entropy of machine learning derived intracranial pressure predictions

Even with the powerful statistical parameters derived from the Extreme Gradient Boost (XGB) algorithm, it would be advantageous to define the predicted accuracy to the level of a specific case, particularly when the model output is used to guide clinical decision-making. The probability density function (PDF) of the derived intracranial pressure predictions enables the computation of a definite integral around a point estimate, representing the event's probability within a range of values. Seven hold-out test cases used for the external validation of an XGB model underwent retinal vascular pulse and intracranial pressure measurement using modified photoplethysmography and lumbar puncture, respectively. The definite integral ±1 cm water from the median (DIICP) demonstrated a negative and highly significant correlation (-0.5213±0.17, p< 0.004) with the absolute difference between the measured and predicted median intracranial pressure (DiffICPmd). The concordance between the arterial and venous probability density functions was estimated using the two-sample Kolmogorov-Smirnov statistic, extending the distribution agreement across all data points. This parameter showed a statistically significant and positive correlation (0.4942±0.18, p< 0.001) with DiffICPmd. Two cautionary subset cases (Case 8 and Case 9), where disagreement was observed between measured and predicted intracranial pressure, were compared to the seven hold-out test cases. Arterial predictions from both cautionary subset cases converged on a uniform distribution in contrast to all other cases where distributions converged on either log-normal or closely related skewed distributions (gamma, logistic, beta). The mean±standard error of the arterial DIICP from cases 8 and 9 (3.83±0.56%) was lower compared to that of the hold-out test cases (14.14±1.07%) the between group difference was statistically significant (p<0.03). Although the sample size in this analysis was limited, these results support a dual and complementary analysis approach from independently derived retinal arterial and venous non-invasive intracranial pressure predictions. Results suggest that plotting the PDF and calculating the lower order moments, arterial DIICP, and the two sample Kolmogorov-Smirnov statistic may provide individualized predictive accuracy parameters.

Atypical Presentation of Idiopathic Intracranial Hypertension: A Case Series and Literature Review

Idiopathic intracranial hypertension (IIH) is a condition in which intracranial pressure (ICP) increases without an apparent cause. Typically, patients present with headaches, dizziness, pulsatile tinnitus, visual disturbances, blurred vision, diplopia, photophobia, visual field defects, and papilledema on fundoscopy. The association between IIH, spontaneous cerebrospinal fluid (CSF) rhinorrhea, and arachnoid cysts has been discussed in the literature; however, there is no clear explanation for this association. We aimed to present a series of four patients with a confirmed diagnosis of IIH with atypical presentations, discuss the management of each case, and provide an explanation for this association to alert clinicians to the atypical presentation of IIH and facilitate early diagnosis and proper treatment of this condition by CSF diversion. This was a retrospective case series of all patients who were diagnosed with IIH and showed improvement after ventriculoperitoneal shunt insertion after failure of at least one operative intervention resulting from primary radiological and clinical findings in 2001 to 2022. Data on demographics, clinical presentation, radiological findings, surgical management, and diagnostic criteria for IIH were recorded. We identified four patients with a confirmed diagnosis of IIH who presented with atypical presentations as follows: intracranial arachnoid cyst, cervical spine arachnoid cyst, giant Virchow perivascular space, and spontaneous CSF (CSF) rhinorrhea. All patients responded to CSF diversion after failure of surgical treatment targeting the primary pathology. IIH should be suspected after the failure of primary surgical treatment in cases of spontaneous CSF rhinorrhea, spinal and cranial arachnoid cysts, and symptomatic ventriculoperitoneal shunt. Treatment in such situations should be directed toward IIH with CSF diversion.

Evaluation of the association between tetracycline-class antibiotic use in patients with acne and idiopathic intracranial hypertension risk: a population-level cohort study

We conducted a population-based retrospective cohort study on the TriNetX US Collaborative Network to investigate whether tetracycline-class antibiotic exposure is associated with idiopathic intracranial hypertension (IIH) development in people with acne. Doxycycline exposure conferred a significantly decreased risk of IIH compared with minocycline, and minocycline exposure was associated with a significantly increased risk of IIH compared with nonsystemic acne treatment. Our findings underscore the need to carefully consider the use of minocycline in acne treatment.

Pseudotumor cerebri with status epilepticus in a child: A rare presentation of vitamin D deficiency

Pseudotumor cerebri (PTC) encompasses a constellation of symptoms caused by elevated intracranial pressure of unclear etiology. Various associations have been described, rarely hypovitaminosis D. Vitamin D deficiency should be considered as a potential etiology of neurological manifestations like PTC and seizures in children. Early diagnosis and correction of vitamin D deficiency is key to preventing morbidity and achieving good outcomes.

Impact of Ramadan fasting on vision and headache-related quality of life in women with idiopathic intracranial hypertension: A prospective observational study

BACKGROUND

Ramadan fasting is an obligatory religious practice for Muslims. However, research data on the effect of Ramadan on idiopathic intracranial hypertension (IIH) symptoms are lacking. This study aimed to study the effect of Ramadan fasting on the severity of headache and visual symptoms and related quality-of-life activities.

METHODS

This prospective cohort study targeted females diagnosed with IIH (n = 102) who were eligible to fast for Ramadan in 2023. The patients were recruited from the Neurology Clinic in Beni-Suef University Hospital, Egypt. Body mass index (BMI), monthly headache days and intensity of headache attacks, six-item Headache Impact Test (HIT-6), and the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) scores during Ramadan were compared to those during the (non-fasting) month of Shaaban, the preceding month to Ramadan.

RESULTS

There was a significant increase in the BMI of patients with IIH in Ramadan compared to the (non-fasting) month of Shaaban, at a median (interquartile range [IQR]) of 30.5 (26.6-35.8) kg/m2 and 30.1 (26.6-35.2) kg/m2, respectively (p = 0.002). The median (IQR) value of monthly headache days was significantly increased during Ramadan in comparison to the (non-fasting) month of Shaaban, at 20 (11.5-30) vs. 15 (10-25) (p < 0.001). There was a statistically significant worsening in the visual analog scale (VAS) scores (median [IQR] 7 [5-8] vs. 6.5 [5-8]), HIT-6 scores (median [IQR] 61 [58-67] vs. 59 [53-61.5]), and NEI-VFQ-25 total scores (median [IQR] 1312.5 [1238.8-1435] vs 1290 [1165-1417.5]) during Ramadan in comparison to the (non-fasting) month of Shaaban (p < 0.001 for all comparisons). The change in BMI in Ramadan was positively correlated with the change in monthly headache days (r = 0.24, p = 0.014), VAS (r = 0.20, p = 0.043), HIT-6 (r = 0.25, p = 0.010) and NEI-VFQ-25 scores (r = 0.24, p = 0.016).

CONCLUSION

Ramadan fasting had an aggravating effect on headache, visual symptoms, and related quality-of-life activities, which might be attributed to weight gain during this month. Whether proper nutritional management to prevent weight gain during Ramadan may help mitigate this worsening effect is a mission of future studies.

Acute Promyelocytic Leukemia: Review of Complications Related to All-Trans Retinoic Acid and Arsenic Trioxide Therapy

The hallmark of acute promyelocytic leukemia (APL) is the presence of the characteristic fusion transcript of the promyelocytic leukemia gene with the retinoic acid receptor α gene (PML::RARA). The PML::RARA fusion is a molecular target for all-trans retinoic acid (ATRA) and arsenic trioxide (ATO). Therapies based on ATRA plus ATO have excellent outcomes in terms of complete remission rates, overall survival, and achievement of deep and durable molecular responses with a very low incidence of relapse. However, although the combination of ATRA and ATO has lower hematologic toxicity than standard chemotherapy, its use is associated with a spectrum of distinctive toxicities, such as differentiation syndrome, liver toxicity, QT interval prolongation, and neurotoxicity. Rigorous monitoring of patients' clinical evolution is indispensable for identifying and addressing each complication. The objective is to maintain an equilibrium between treatment-induced adverse events and therapeutic efficacy. This paper focused on non-hematologic complications associated with the combination of ATRA and ATO. Additionally, we discuss late-onset complications of this therapy. In summary, the majority of treatment-related adverse events are manageable, self-limiting, and reversible. More so, there seems to be a lower incidence rate of secondary neoplasms compared to standard chemotherapy. However, further research is required to assess how the ATRA plus ATO regimen affects the emergence of additional comorbidities.

Understanding the pathophysiology of idiopathic intracranial hypertension (IIH): a review of recent developments

Idiopathic intracranial hypertension (IIH) is a condition of significant morbidity and rising prevalence. It typically affects young people living with obesity, mostly women of reproductive age, and can present with headaches, visual abnormalities, tinnitus and cognitive dysfunction. Raised intracranial pressure without a secondary identified cause remains a key diagnostic feature of this condition, however, the underlying pathophysiological mechanisms that drive this increase are poorly understood. Previous theories have focused on cerebrospinal fluid (CSF) hypersecretion or impaired reabsorption, however, the recent characterisation of the glymphatic system in many other neurological conditions necessitates a re-evaluation of these hypotheses. Further, the impact of metabolic dysfunction and hormonal dysregulation in this population group must also be considered. Given the emerging evidence, it is likely that IIH is triggered by the interaction of multiple aetiological factors that ultimately results in the disruption of CSF dynamics. This review aims to provide a comprehensive update on the current theories regarding the pathogenesis of IIH.

Navigating the Enigma: A Comprehensive Review of Idiopathic Intracranial Hypertension

An unidentified source of increased intracranial pressure is a hallmark of idiopathic intracranial hypertension (IIH), also referred to as pseudotumor cerebri. It mainly affects young, obese women, yet it can happen to anyone, regardless of age, gender, or weight. IIH presents with symptoms such as headaches, visual disturbances, and pulsatile tinnitus and can lead to severe complications, including vision loss, if left untreated. Diagnosis involves clinical evaluation, neuroimaging, and lumbar puncture, while management options include medical interventions and surgical procedures. This review provides a comprehensive overview of IIH, including its etiology, clinical presentation, epidemiology, complications, management approaches, and challenges. Increased awareness among healthcare professionals, standardized diagnostic criteria, and further research efforts are essential for improving outcomes and quality of life for individuals with IIH.

Idiopathic intracranial hypertension in two twin sisters

Idiopathic intracranial hypertension (IIH) is a condition of unknown aetiology characterised by an increase in the intracranial pressure. Familial cases of IIH are rare and not well-understood. We present two monozygotic twins who developed IIH two years apart. The case involves two monozygotic female twins developing IIH in their 50s. They presented with a history of blurry vision and headaches. The diagnosis included the neurological, radiological and ophthalmological examination, excluding other causes. Both patients received treatment with acetazolamide, successfully resolving the papilloedema and restoring a normal visual field. This case highlights the occurrence of IIH among twins presenting at similar periods, emphasising the potential genetic influence. Clinicians should alert and educate the family regarding the risk factors and potential symptoms of this condition in the unlikely occurrence that other family members are affected.

Changes in Prevalence of Idiopathic Intracranial Hypertension in the United States Between 2015 and 2022, Stratified by Sex, Race, and Ethnicity

BACKGROUND AND OBJECTIVES

With the obesity epidemic within the United States, the prevalence of idiopathic intracranial hypertension (IIH) is predicted to rise. IIH prevalence and racial disparities have rarely been reported in the United States. The purpose of this study was to evaluate the prevalence of IIH in a large national database while stratifying by sex, age, race, and ethnicity.

METHODS

This was a cross-sectional epidemiologic evaluation conducted in the TriNetX US Collaborative network using data from 2015 to 2022. Patients with an International Classification of Diseases code of IIH and papilledema or unspecified papilledema were included in the study. Any secondary cause of intracranial hypertension including cerebral neoplasms and hydrocephalus were excluded from the study. IIH trends were later compared with TriNetX cohort obesity trends. Prevalence and prevalence odds ratios (ORs) were calculated in Microsoft Excel and R Studio.

RESULTS

Among 85 million patients in this database, a 1.35 times increase in the prevalence of IIH occurred between 2015 and 2022 from 7.3 (95% CI 6.9-7.7) individuals per 100,000 to 9.9 (95% CI 9.5-10.3) individuals per 100,000 in 2022. In 2022, Black female individuals had the highest prevalence of IIH with 22.7 individuals per 100,000 compared with the 13.7 White female individuals per 100,000. Patients aged 11-17 years showed the largest growth of IIH prevalence with female individuals increasing by 10 individuals per 100,000 by 2022. Overall, Black and Hispanic patients had the largest prevalence OR of IIH at 1.66 (95% CI 1.49-1.85) and 1.33 (95% CI 1.14-1.56), respectively, compared with White female patients.

DISCUSSION

IIH is a rapidly increasing health care concern for the US population, particularly among adolescent patients. Black and Hispanic female individuals are most predominately affected by this incapacitating disorder.

Idiopathic intracranial hypertension secondary to fluoroquinolone therapy: French pharmacovigilance data review

We investigate spontaneous reports of IIH related to fluoroquinolones recorded in the French national pharmacovigilance database in order to detect a possible pharmacovigilance signal. The association between IIH risk and fluoroquinolone exposure was assessed using a case/non-case study. Between 1985 and July 2023, 17 reports of IIH after fluoroquinolone exposure were recorded. No specific fluoroquinolone was predominant. IIH led to death in one case and blindness in one case. The Reporting Odds Ratio was 2.58 (95% confidence interval 1.59-4.19). We highlight statistically significant disproportionality, which constitutes a pharmacovigilance signal. IIH risk after fluoroquinolone exposure is a class effect.

The Vienna idiopathic intracranial hypertension database-An Austrian registry

BACKGROUND

Idiopathic intracranial hypertension (IIH) is becoming increasingly more prevalent bearing the risk of visual impairment and affecting the quality of life. Clinical presentation and outcome are heterogeneous. Large, well-characterized cohorts are scarce.

OBJECTIVE

To characterize the clinical spectrum, diagnostic findings, therapeutic management, and outcome of IIH.

METHODS

We identified patients with IIH according to modified Friedman criteria treated at our center between 2014 and 2021. The Vienna IIH database is described in detail.

RESULTS

Of 113 patients 89% were female (mean age 32.3 years). Median body mass index (BMI) was 31.8, with 85% overweight (BMI > 25) and 5% were classified as IIH without papilledema. Headache was present in 84% and showed migraine features in 43%. Median opening pressure in lumbar puncture was 31 cmH2O. Pharmacotherapy (predominantly acetazolamide) was established in 99%, 56% required at least 1 therapeutic lumbar puncture and 13% a surgical intervention. After a median 3.7 years follow-up, 57% had achieved significant weight loss, papilledema was present in 59% and headache in 76% (58% improved). Comparing initial presentation to follow-up, perimetry was abnormal in 67% vs. 50% (8% worsened, 24% improved) and transorbital sonography in 87% vs. 65% with a median optic nerve sheath diameter of 5.4 mm vs. 4.9 mm. Median peripapillary retinal nerve fiber layer thickness decreased from 199 µm to 99 µm and ganglion cell layer volume from 1.13 mm3 to 1.05 mm3.

CONCLUSION

The large representative Vienna IIH cohort characterizes IIH-related symptoms, diagnostic findings, treatment, and outcome emphasizing substantial long-term sequelae of IIH. Future analyses will aim to refine phenotyping and identify factors predicting outcome.

Idiopathic intracranial hypertension in Omani adults: A tertiary center experience

BACKGROUND

To evaluate the clinical profile, risk factors, and ophthalmic diagnostic and monitoring tools in Omani patients with idiopathic intracranial hypertension (IIH) using optical coherence tomography (OCT).

METHODS

A retrospective single institutional cohort study on Omani patients with a fulfilled diagnosis of IIH from January 1, 2014, to January 1, 2020, was conducted. The data obtained from the neuro-ophthalmic clinic contained age of onset of the disease, gender of patients, body mass index (BMI), presence of other associated conditions, and medication use.

RESULTS

Our study group comprised 21 patients with IIH with an annual incidence rate of 2.8 per 100,000 population. Female-to-male ratio was 9.5:1 with a mean age of 27.24 ± 7.1. Headaches appeared to be the most prevalent symptom in 21 (100%) patients, followed by transient obscuration of vision in 9 (42.9%) patients and diplopia in 3 (14.3%) patients, and the least common symptom was pulsatile tinnitus in 2 (9.5%) patients. Increased BMI was seen in 19 (90.5%) patients and noted to be the most prevalent predisposing factor among our study group. The use of oral contraceptive pills was documented in 4 (19%) patients and 1 (4.8%) patient was noted to have polycystic ovary syndrome. All patients (100%) had a best-corrected visual acuity of 1.0 in both eyes pre- and postrecovery and 7 (33.3%) patients had an enlarged blind spot on visual field testing. All patients had papilledema on presentation and an average of 14.1 months to resolve to normal clinically and on OCT monitoring. All patients were treated with medications and only 1 (4.8%) continued to have intractable headaches that did not respond to maximum medical therapy and required surgery.

CONCLUSION

The incidence of IIH in the Omani population was found to be less than neighboring countries but comparable worldwide. OCT is considered a useful tool to confirm and document papilledema and more importantly monitor recovery.

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.

Non-invasive Measurement of the Viscoelasticity of the Optic Nerve and Sclera for Assessing Papilledema: A Pilot Clinical Study

OBJECTIVE

The purpose of this study was to evaluate our novel ultrasound vibro-elastography (UVE) technique for assessing patients with papilledema by non-invasively measuring shear wave speed (SWS), elasticity and viscosity properties of the optic nerve and sclera.

METHODS

Shear wave speeds were measured at three frequencies-100, 150 and 200 Hz-on the optic nerve and sclera tissues for assessing patients with papilledema resulting from idiopathic intracranial hypertension (IIH). The method was evaluated in six papilledema patients and six controls on two separate locations for each participant (i.e., optic nerve and posterior sclera). SWSs of the optic nerve and sclera were analyzed by using a 2-D speed map technique within a circular region of interest (ROI) (i.e., the diameter of the ROI was 1.5 mm × 3.0 mm at the optic nerve and sclera, respectively). Elasticity and viscosity were then analyzed using the wave speed dispersion over the three frequencies.

RESULTS

We measured values of SWS at both locations, optic nerve and sclera, of the right eye and left eye at three different frequencies in IIH patients and controls. The SWS (mean ± standard deviation [m/s]) of the right eye was significantly higher at the sclera in IIH patients compared with controls (i.e., patients vs. controls: 5.91 ± 0.54 vs. 3.86 ± 0.56, p < 0.0001 at 100 Hz), but there was no significant difference at the optic nerve (i.e., patients vs. controls: 3.62 ± 0.39 vs. 3.36 ± 0.35, p = 0.1100 at 100Hz). We observed increased elasticity (kPa) in IIH patients, indicating there are significant differences in elasticity between patients and controls at the optic nerve and sclera (i.e., right eye [patients vs. controls]: 14.42 ± 6.59 vs. 6.5 ± 5.71, p = 0.0065 [optic nerve]; 33.04 ± 10.62 vs. 9.16 ± 7.15, p < 0.0001 [sclera]). Viscosity was also (Pa·s) higher in the sclera and optic nerve of the left eye (i.e., left eye [patient vs. control]: 8.89 ± 4.37 vs. 7.27 ± 5.01, p = 0.3790 (optic nerve); 16.05 ± 10.79 vs. 8.49 ± 6.09, p < 0.0194 [sclera]).

CONCLUSION

This research illustrates the feasibility of using our UVE system to evaluate stiffness of different tissues in the eye non-invasively. It suggests that the viscoelasticity of the posterior sclera is higher than that of the optic nerve. We found that the posterior sclera is stiffer than the optic nerve in patients with papilledema resulting from IIH, making UVE a potential non-invasive technique for assessing papilledema.

Levonorgestrel intrauterine device use and incident idiopathic intracranial hypertension among commercially insured women

OBJECTIVES

To estimate the hazard of incident idiopathic intracranial hypertension, a potentially blinding condition, among women using levonorgestrel intrauterine devices (LNG-IUD) compared to copper IUD, as conflicting associations have been reported.

STUDY DESIGN

This retrospective, longitudinal cohort study identified women ages 18-45 years in a large care network (January 1, 2001, to December 31, 2015) using LNG-IUD, subcutaneous etonogestrel implant, copper IUD, tubal device/surgery, or hysterectomy. Incident idiopathic intracranial hypertension was defined as the first diagnosis code for after 1 year without any codes and following brain imaging or lumbar puncture. Kaplan-Meier analysis estimated time-dependent probabilities of idiopathic intracranial hypertension at 1 and 5 years after incident contraception use, stratified by type. Cox regression estimated the hazard of idiopathic intracranial hypertension associated with LNG-IUD use compared to copper IUD (primary comparison) after adjusting for sociodemographics and factors associated with idiopathic intracranial hypertension (e.g., obesity) or contraception selection. A sensitivity analysis with propensity score-adjusted models was performed.

RESULTS

Of 268,280 women, 78,175 (29%) used LNG-IUD, 8715 (3%) etonogestrel implant, 20,275 (8%) copper IUD, 108,216 (40%) hysterectomy, 52,899 (20%) tubal device/surgery, and 208 (0.08%) developed idiopathic intracranial hypertension over a mean follow-up of 2.4 ± 2.4 years. Also, 1-/5-year Kaplan-Meier idiopathic intracranial hypertension probabilities were 0.0004/0.0021 for LNG-IUD and 0.0005/0.0006 for copper IUD users. LNG-IUD use did not show significantly different hazard of idiopathic intracranial hypertension compared to copper IUD (adjusted hazard ratio 1.84 [95% CI 0.88, 3.85]). Sensitivity analyses were similar.

CONCLUSIONS

We did not observe a significantly increased hazard of idiopathic intracranial hypertension among women using LNG-IUD compared to copper IUDs.

IMPLICATIONS

The lack of an association between LNG-IUD use and idiopathic intracranial hypertension in this large observational study provides reassurance to women considering initiation or continued use of this highly effective contraceptive method.

Frontonasal Encephalocele Complicated With Pseudotumor Cerebri: A Case Report and Literature Review

Primary pseudotumor cerebri syndrome (PPTS) is a rare disorder of elevated intracranial pressure (ICP) in the absence of an identifiable underlying etiology. Afflicted patients are usually obese women in their reproductive age presenting with symptoms of elevated ICP. Seldom, patients can present with an encephalocele. We reported a case of a 31-year-old female who initially presented to our center with complaints of headaches, foreign body sensation in the nasal cavity, and decreased ability to smell. Brain computed tomography (CT) scan showed a large intranasal encephalocele and defect along the frontal skull base, through which brain tissue was herniating. The patient was successfully treated surgically by implantation of a lumboperitoneal shunt to manage the high ICP caused by her PPTS. In combination, reconstruction of the frontal skull base defect for the encephalocele was performed. Currently, the patient is doing well despite some on-and-off headaches.

Hydroxyapatite Use in Repair of Lateral Skull Base CSF Leaks Via Transmastoid Approach: When Does It Work?

OBJECTIVE

The objective of this study is to evaluate the efficacy and outcomes of using a transmastoid approach with hydroxyapatite cement to repair lateral skull base cerebrospinal fluid (CSF) leaks.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary-level care hospital.

PATIENTS

Surgical patients 18 years or older between 2013 and 2022 with spontaneous CSF leak.

INTERVENTIONS

Trans-mastoid approach for skull base repair using hydroxyapatite cement.

MAIN OUTCOME MEASURES

Failure rate of repair; location and size of defect, patient demographic factors.

RESULTS

Of the 60 total defects (55 patients, 5 bilateral repairs) that underwent CSF leak repair using hydroxyapatite cement, the success rate was 91.66% (55 successful repairs). The average defect size in unsuccessful repairs was 1.15 cm compared with 0.71 cm for successful repairs. In addition, 80% (4/5) of the failed repairs were in the tegmen tympani region. Higher failure rate was noted in women (3/5) and in former smokers (4/5). Average time to recurrent symptoms was 1.75 years in the failed repair cohort. Of the patients with failed repairs, 4/5 were prescribed acetazolamide before their second procedure with successful second repair. In addition, five patients experienced postoperative headaches, three (5.4%) of whom required placement of VP shunts to relieve increased intracranial pressure. Two patients (3.6%) had complications of either infection or hearing loss.

CONCLUSIONS

Transmastoid approach utilizing hydroxyapatite is a successful approach for CSF leak repair, with a low complication and failure rate. Women, prior smoking history, and larger defects in the tegmen tympani region may need alternative materials or approach for repair. Long follow-up is warranted as recurrence of symptoms might be delayed. In cases of benign intracranial hypertension, adjuvant treatment with either acetazolamide or VP shunt placement may prevent failures.

A Case Report of Pseudotumor Cerebri Syndrome with a Huge Retroperitoneal Cyst

Background: Aside from primary pseudotumor cerebri syndrome (PTCS) with an unknown etiology (i.e., idiopathic intracranial hypertension), which typically occurs in association with obesity, several conditions including cerebral venous abnormalities, drug use, and hormonal imbalance may be a secondary cause of PTCS. However, a focal space-occupying lesion outside of the brain as a cause of PTCS has rarely been reported. Case Presentation: A previously healthy 34-year-old man presented with blurred vision for three weeks. The patient had a three-month preceding history of worsening headache. On admission, he was hypertensive (160/90 mmHg) and underweight with a body mass index of 18.4 kg/m2. Fundus examination documented papilledema in both eyes. Neurological examination was unremarkable except for mild nuchal rigidity, and results of routine serologic testing were normal. Gadolinium-enhanced brain magnetic resonance imaging revealed bilateral posterior scleral flattening, suggesting intracranial hypertension. There was no other abnormal brain parenchymal lesion or meningeal enhancement. Cerebrospinal fluid (CSF) assay showed a markedly increased opening pressure (30.0 cmH2O) with normal CSF composition. A tentative diagnosis of PTCS was made based on ophthalmological, neuroradiological, and laboratory findings. During differential diagnosis, abdomen computed tomography demonstrated a huge benign cystic lesion (14.7 × 10.6 × 16.4 cm) in the right retroperitoneal space, which originated from the mesentery and resulted in hydronephrosis and renovascular hypertension due to external compression of the right kidney. Other evaluations were unremarkable. After successful surgical removal of the cyst, clinical symptoms such as headache, blurred vision, and papilledema on fundus examination were markedly improved, and blood pressure was normalized during the three-month follow-up period. Conclusions: A large retroperitoneal cyst that can increase intra-abdominal pressure could be a rare cause of PTCS. Therefore, meticulous evaluation is warranted for patients with PTCS, especially those without known risk factors.

Clinical course of asymptomatic patients with papilledema from idiopathic intracranial hypertension

OBJECTIVE

Idiopathic intracranial hypertension (IIH) is defined as elevated intracranial pressure (ICP) with normal cerebrospinal fluid content in the absence of an identifiable cause. Patients often experience symptoms related to elevated ICP (e.g., headache); however, a subgroup of patients with elevated ICP may have optic disc edema without any associated symptoms. There are limited data about this subgroup in the literature. Our aim in this study was to characterize the initial clinical findings and visual outcomes over the follow-up period in this group of asymptomatic patients.

METHODS

We performed a retrospective review of all patients who were referred to the neuro-ophthalmology service at Baylor College of Medicine for evaluation of papilledema between January 2012 and June 2020. Medical records of 139 consecutive patients with papilledema were reviewed. Patients were included in the analysis if they met the criteria for the diagnosis of IIH, had bilateral optic disc edema, and did not have any symptoms of elevated ICP.

RESULTS

Of the 139 charts reviewed, 5 patients met the inclusion criteria. All 5 patients were female with a mean age of 25.2 years (range, 13-48 years). The mean body mass index was 36.3 kg/m2 (range, 31.5-40 kg/m2), and the mean follow-up period was 3 years (range, 12 months-5 years).

CONCLUSION

Our results demonstrate that the disease course for patients who present with asymptomatic IIH can be variable, yet still visually significant. Despite the absence of symptoms, patients can progress to symptomatic disease or experience persistent optic disc swelling or pallor even with the use of medication to lower ICP. To our knowledge, this is the first retrospective study characterizing the clinical course of papilledema from IIH in asymptomatic individuals.

Endoscopic endonasal optic nerve sheath decompression (EONSD) for idiopathic intracranial hypertension: Technical details and meta-analysis

BACKGROUND

The neurosurgical management of idiopathic intracranial hypertension (IIH) remains controversial. Although shunting and newer endovascular stenting techniques are part of the neurosurgical armamentarium to treat medically refractory IIH symptoms, optic nerve sheath fenestration has traditionally been performed by ophthalmologists.

OBJECTIVE

We present a detailed cadaveric dissection that simulates the endoscopic endonasal optic nerve sheath decompression (EONSD) technique along with the literature review.

METHODS

EONSD was performed in four freshly injected cadaveric specimens. Additionally, a systematic review from different electronic databases has been done.

RESULTS

Bilateral EONSD was performed in all specimens without significant technical difficulties. Based on our experience, there is no need to expose the periorbita or orbital apex. The primary anatomic landmarks were the optic canal, the lateral opticocarotid recess, the tuberculum, the limbus, and the clinoid segment of the internal carotid artery. Based on the systematic review, 68 patients (77.9% female) underwent EONSD, with a mean age of 33.4 ± 6.9 years in adult patients. Follow-up ranged from 3 to 58 months across different studies. The pooled meta-analysis showed headache, papilledema, and visual disturbance improvement in 78% [95%CI 0.65-0.90], 72% [95%CI 0.61-0.83], and 88% [95%CI 0.80-0.96] of cases who underwent EONSD, respectively. The subgroup analysis showed there was no statistically significant difference between unilateral and bilateral EONSD in terms of different measured outcomes.

CONCLUSION

EONSD is a feasible surgical procedure that may obviate the need for shunting in patients with IIH. Although clinical studies showed that EONSD is a safe and effective technique, further studies are required to establish the preferences of either unilateral or bilateral approaches.

Venous Sinus Stenting: Safety and Health Care Resource Evaluation for Optimal Recovery in an Evolving Health Care Environment

BACKGROUND

Increasing evidence supports the effectiveness of venous sinus stenting (VSS) with favorable outcomes, safety, and expenses compared with shunting for idiopathic intracranial hypertension. Yet, no evidence is available regarding optimal postoperative recovery, which has increasing importance with the burdens on health care imposed by the coronavirus disease 2019 pandemic. We examined adverse events and costs after VSS and propose an optimal recovery pathway to maximize patient safety and reduce stress on health care resources.

METHODS

A retrospective review was undertaken of elective VSS operations performed from May 2008 to August 2021 at a single institution. Primary data included hospital length of stay, intensive care unit (ICU) length of stay, adverse events, need for ICU interventions, and hospital costs.

RESULTS

Fifty-three patients (98.1% female) met the inclusion criteria. Of these patients, 51 (96.2%) were discharged on postoperative day (POD) 1 and 2 patients were discharged on POD 2. Both patients discharged on POD 2 remained because of groin hematomas from femoral artery access. There were no major complications or care that required an ICU. Eight patients (15.1%) were lateralized to other ICUs or remained in a postanesthesia care unit because the neurosciences ICU was above capacity. Total estimated cost for initial recovery day in a neurosciences ICU room was $2361 versus $882 for a neurosurgery/neurology ward room. In our cohort, ward convalescence would save an estimated $79,866 for bed placement alone and increase ICU bed availability.

CONCLUSIONS

Our findings reaffirm the safety of VSS. These patients should recover on a neurosurgery/neurology ward, which would save health care costs and increase ICU bed availability.

Prevalence and utility of overnight pulse oximetry as a screening tool for obstructive sleep apnoea in newly diagnosed idiopathic intracranial hypertension

BACKGROUND

Idiopathic intracranial hypertension (IIH) is a condition of raised intracranial pressure (ICP). Obstructive sleep apnoea (OSA) has been shown to cause episodic rises in ICP and is frequently reported in patients with IIH. The aim of this study is to identify the prevalence of OSA in a cohort of IIH patients.

METHODS

We conducted a retrospective case notes review as part of a service evaluation of newly diagnosed IIH patients who were all referred for OSA screening with overnight pulse oximetry. The 3% oxygen desaturation index (3% ODI) was used to evaluate the presence and severity of OSA. The clinical outcomes of patients who received continuous positive airway pressure (CPAP) therapy as treatment for OSA were reviewed.

RESULTS

In our cohort of newly diagnosed IIH patients, the yield of overnight pulse oximetry as a screening tool was 48.6% for OSA and 15.3% for moderate to severe OSA. We found that age (p = 0.0008), BMI (p < 0.0001), vitamin B₁₂ (p = 0.0183), and a higher Epworth Sleep Score (p = 0.0269) correlated with more severe OSA. Eleven (10%) patients had CPAP therapy and those with good adherence alongside weight loss or medical therapy found improvements in symptoms of raised ICP.

CONCLUSION

We report the largest series of consecutive IIH patients screened for OSA using overnight pulse oximetry. The high rate of OSA highlights a potential role for the recognition and management of OSA in the IIH patient cohort. Further studies on the potential contribution of OSA as a cause of raised ICP in the IIH cohort is warranted.

[Impact of COVID-19 lockdown on patients with idiopathic intracranial hypertension in Spain]

INTRODUCTION

The nationwide lockdown implemented in Spain in March 2020 in response to the 2019 coronavirus disease pandemic (COVID-19) could have had an effect on the clinical situation, disease management and access to care in patients with idiopathic intracranial hypertension.

PATIENTS AND METHODS

A cross-sectional observational study was conducted by means of an online survey. The frequency and impact of headache, visual symptoms, dizziness, cognitive symptoms, diplopia, anxiety and depression on patients' quality of life were recorded. Disease treatment and delays experienced in accessing care were recorded. Participants were grouped according to the time elapsed since diagnosis.

RESULTS

A total of 112 patients participated in the study (103 women). The average time since disease onset was 6.25 years. Headache, anxiety and depression were responsible for considerable impact in the period prior to lockdown. The impact of headache was not aggravated during lockdown, but anxiety and depression did become significantly worse. Recently diagnosed participants reported higher rates of anxiety, depression, dizziness and diplopia; chronically diagnosed participants reported a higher frequency of cognitive symptoms.

CONCLUSIONS

The clinical situation of the participants deteriorated during lockdown, although the differences were smaller than previously thought. This was probably because the baseline situation was more severe than expected. Further studies are needed to clarify the medium and long-term impact of the COVID-19 pandemic on patients with idiopathic intracranial hypertension.

Telltale Signs of Idiopathic Intracranial Hypertension With Normal Opening Cerebrospinal Fluid Pressure

Introduction

Idiopathic Intracranial Hypertension (IIH) with normal opening cerebrospinal fluid (CSF) pressure comprises a rare IIH variant.

Case Report

We report the case of a non-obese Caucasian woman, who presented with asymmetrical papilledema, typical IIH-findings on optic nerve sonography and brain magnetic resonance imaging (MRI), and was diagnosed with IIH despite normal opening CSF pressure. Following treatment with acetazolamide, a complete remission of her symptoms was achieved, accompanied by significant improvement of the fundoscopy findings.

Conclusion

Although normal opening CSF pressure in IIH patients is rare, clinicians should be aware of this IIH variant and promptly indicate IIH treatment in patients presenting with typical clinical symptoms and neuroimaging findings suggestive of IIH.

Pseudotumor Cerebri Postpartum: A Case Report

Idiopathic intracranial hypertension (IIH), called pseudotumor cerebri, could cause postpartum headaches. Generally, this diagnosis is idiopathic and treatment is mainly medical to avoid serious complications of possible vision loss. In this paper, we report the case of a 24-year-old lady who developed a similar constellation of symptoms and was diagnosed with this condition. Postpartum, the patient demonstrated symptoms of headache and vision disturbances. Workup ruled out infectious processes and intracranial pathologies. Normal cranial magnetic resonance imaging (MRI) and high cerebrospinal fluid (CSF) pressure during lumbar puncture led to a diagnosis of IIH. Initiation of medication allowed rapid improvement of symptoms and evaded imminent morbidity. Further discussion in light of the latest findings of the literature is held after the presentation of the case. This case sheds light on the importance on importance of fundoscopy in patients demonstrating new-onset headaches especially postpartum with the absence of intracranial pathologies.

Features of Idiopathic Intracranial Hypertension on MRI With MR Elastography: Prospective Comparison With Control Individuals and Assessment of Postintervention Changes

BACKGROUND. Understanding of dynamic changes of MRI findings in response to intracranial pressure (ICP) changes in idiopathic intracranial hypertension (IIH) is limited. Brain stiffness, as assessed by MR elastography (MRE), may reflect changes in ICP. OBJECTIVE. The purpose of this study was to compare pituitary height, ventricular size, and brain stiffness between patients with IIH and control individuals and to evaluate for changes in these findings in patients with IIH after interventions to reduce ICP. METHODS. This prospective study included 30 patients (28 women, two men; median age, 29.9 years) with IIH and papilledema and 21 control individuals (21 women, 0 men; median age, 29.1 years), recruited from January 2017 to July 2019. All participants underwent 3-T brain MRI with MRE; patients with IIH underwent additional MRI examinations with MRE after acute intervention (lumbar puncture with normal closing pressure; n = 11) and/or chronic intervention (medical management or venous sinus stenting with resolution or substantial reduction in papilledema; n = 12). Pituitary height was measured on sagittal MP-RAGE images. Ventricular volumes were estimated using unified segmentation, and postintervention changes were assessed by tensor-based morphometry. Stiffness pattern score and regional stiffness values were estimated from MRE. RESULTS. In patients with IIH, median pituitary height was smaller than in control individuals (3.1 vs 4.9 mm, p < .001) and was increased after chronic (4.0 mm, p = .05), but not acute (2.3 mm, p = .50), intervention. Ventricular volume was not different between patients with IIH and control individuals (p = .33) and did not change after acute (p = .83) or chronic (p = .97) intervention. In patients with IIH, median stiffness pattern score was greater than in control individuals (0.25 vs 0.15, p < .001) and decreased after chronic (0.23, p = .11) but not acute (0.25, p = .49) intervention. Median occipital lobe stiffness was 3.08 kPa in patients with IIH versus 2.94 kPa in control individuals (p = .07) and did not change after acute (3.24 kPa, p = .73) or chronic (3.10 kPa, p = .83) intervention. CONCLUSION. IIH is associated with a small pituitary and increased brain stiffness pattern score; both findings may respond to chronic interventions to lower ICP. CLINICAL IMPACT. The "partially empty sella" sign and brain stiffness pattern score may serve as dynamic markers of ICP in IIH.

Bilateral papilledema with vision loss due to post-COVID-19-induced thiamine deficiency: illustrative case

BACKGROUND

Bilateral papilledema with vision loss is considered a neurosurgical emergency due to high intracranial pressure. However, it may not be the only cause of papilledema. The authors reported an association among coronavirus disease 2019 (COVID-19), bilateral papilledema, blindness, and Wernicke's encephalopathy (WE).

OBSERVATIONS

An 18-year-old woman presented to the neurosurgery service with rapid profound vision loss and bilateral papilledema. She had COVID-19 3 months earlier with subsequent loss of smell (anosmia) and taste (ageusia), which resulted in hyperemesis and a 43-lb weight loss. Examination revealed ataxia, horizontal nystagmus, and blindness. Magnetic resonance imaging and magnetic resonance venography of her brain were normal. Presumptive diagnosis of WE was made, and she was treated with intravenous thiamine with restoration of vision within 48 hours. Patient's thiamine level was less than half the normal value.

LESSONS

Neurosurgeons should be aware of this unique correlation between papilledema and vision loss and its association with WE due to post-COVID-19 hyperemesis and weight loss from anosmia and ageusia.

Accuracy and reliability of magnetic resonance imaging in the diagnosis of idiopathic intracranial hypertension

PURPOSE

To determine the diagnostic utility of brain magnetic resonance imaging (MRI) findings in patients with idiopathic intracranial hypertension (IIH) and to investigate the significance of evaluating radiological findings together with neurological and ophthalmological data in the diagnosis of IIH.

MATERIALS AND METHODS

All consecutive patients diagnosed with IIH in our tertiary neuro-ophthalmology center between January 1, 2018 and March 15, 2020, were included in the study. The clinical, radiological, and ophthalmological findings of IIH patients were compared with the control group with similar demographic characteristics.

RESULTS

A total of 98 patients, 49 cases and 49 controls, were included in the study. Lateral ventricular index had the highest area under the curve (AUC) value (0.945) for prediction of disease group followed by sella height category (AUC = 0.915) and optic nerve tortuosity (AUC = 0.855) According to the multivariate model we developed, caudate index (OR = 0.572, 95% CI 0.329-0.996), lateral ventricle index (OR = 3.969, 95% CI 1.851-8.509) and bilateral optic nerve tortuosity (OR = 22,784, 95% CI 2.432-213.450) were significant predictors for disease group.

CONCLUSION

Tortuosity in the optic nerve, lateral ventricular index and caudate index can be used as MRI parameters supporting the diagnosis of IIH in clinically suspicious cases. A holistic approach to the clinical and radiological findings of the cases in the diagnosis of IIH can prevent overdiagnosis and enable early correct diagnosis.

Pressure-Volume Relationships in the Spinal Canal and Potential Neurological Complications After Epidural Fluid Injections

High-volume fluid injections into the spinal canal may lead to severe neurological complications. But when anatomical or pathological conditions in the spinal canal are unfavorable, even small volume epidural injections can cause dangerously high epidural, subarachnoid, and intracranial pressures or pressure gradients. Data obtained from the scientific literature and direct clinical observation are used to derive a first-order approximation of epidural, subarachnoid, and intracranial pressure responses to epidural fluid injections. Maximum allowable fluid volumes for single or multiple divided fluid injections over time are calculated. In the presence of spinal pathology, 10 ml of fluids may increase epidural pressure to &gt;100 mmHg. Injection speed &gt;4 ml per second may also generate dangerously high intraspinal and intracranial pressures. Intermitted bolus injections provide limited protection, but intraspinal pressures may rise very fast when a critical total injected volume is reached. Potential complications of increased intracranial pressures or large pressure waves include nerve palsies, tinnitus, blindness, stroke, and death. Spinal injections or endoscopy should be performed in an awake responsive patient or with direct cerebrospinal fluid pressure monitoring. A set of guidelines for epidural fluid management is given.

Temporal Lobe Encephalocele with Epilepsy in A Young Female: An Atypical Presentation of Idiopathic Intracranial Hypertension

Idiopathic intracranial hypertension (IIH) is typically described in a middle-aged female and present with symptoms of headache, transient visual obscuration, photophobia, diplopia, rarely with pulsatile tinnitus. Seizure as a sole manifestation is very rare. Here we present a case of a young non-obese female with epilepsy, and imaging revealed temporal lobe encephalocele with typical imaging features of IIH. She underwent further workup, which confirmed the diagnosis of idiopathic intracranial hypertension.

Linear interactions between intraocular, intracranial pressure, and retinal vascular pulse amplitude in the fourier domain

Purpose

To compare the retinal vascular pulsatile characteristics in subjects with normal (ICP_n) and high (ICP_h) intracranial pressure and quantify the interactions between intraocular pressure, intracranial pressure, and retinal vascular pulse amplitude in the Fourier domain.

Materials and methods

Twenty-one subjects were examined using modified photoplethysmography with simultaneous ophthalmodynamometry. A harmonic regression model was fitted to each pixel in the time-series, and used to quantify the retinal vascular pulse wave parameters including the harmonic regression wave amplitude (HRW_a). The pulse wave attenuation was measured under different ranges of induced intraocular pressure (IOP_i), as a function of distance along the vessel (V_Dist). Intracranial pressure (ICP) was measured using lumbar puncture. A linear mixed-effects model was used to estimate the correlations between the Yeo-Johnson transformed harmonic regression wave amplitude (HRW_a-YJt) with the predictors (IOP_i, V_Dist and ICP). A comparison of the model coefficients was done by calculating the weighted Beta (β_x) coefficients.

Results

The median HRW_a in the ICP_n group was higher in the retinal veins (4.563, interquartile range (IQR) = 3.656) compared to the retinal arteries (3.475, IQR = 2.458), p<0.0001. In contrast, the ICP_h group demonstrated a reduction in the median venous HRW_a (3.655, IQR = 3.223) and an elevation in the median arterial HRW_a (3.616, IQR = 2.715), p<0.0001. Interactions of the pulsation amplitude with ICP showed a significant disordinal interaction and the loss of a main effect of the Fourier sine coefficient (b_n1) in the ICP_h group, suggesting that this coefficient reflects the retinal vascular response to ICP wave. The linear mixed-effects model (LME) showed the decay in the venous (HRW_a-YJt) was almost twice that in the retinal arteries (−0.067±0.002 compared to −0.028±0.0021 respectively, p<0.00001). The overall interaction models had a total explanatory power of (conditional R²) 38.7%, and 42% of which the fixed effects explained 8.8%, and 5.8% of the variance (marginal R²) for the venous and arterial models respectively. A comparison of the damping effect of V_Dist and ICP showed that ICP had less influence on pulse decay than distance in the retinal arteries (β_ICP = -0.21, se = ±0.017 compared to βVDist=-0.26, se = ±0.019), whereas the mean value was equal for the retinal veins (venous βVDist=-0.42, se = ±0.015, β_ICP = -0.42, se = ±0.019).

Conclusion

The retinal vascular pulsation characteristics in the ICP_h group showed high retinal arterial and low venous pulsation amplitudes. Interactions between retinal vascular pulsation amplitude and ICP suggest that the Fourier sine coefficient b_n1 reflects the retinal vascular response to the ICP wave. Although a matrix of regression lines showed high linear characteristics, the low model explanatory power precludes its use as a predictor of ICP. These results may guide future predictive modelling in non-invasive estimation of ICP using modified photoplethysmography.

Developing a "Fast-Track" Strategy for Interventional Management of Patients With Idiopathic Intracranial Hypertension

Idiopathic intracranial hypertension (IIH) has an increasing incidence worldwide over the past decade, with a high economic burden on patients and society. Up to 10% of patients with IIH have progressive visual decline requiring an invasive intervention (including cerebrospinal fluid shunting, cerebral dural sinus stenting, or optic nerve sheath fenestration [ONSF]). IIH patients with visual decline usually undergo evaluation and initial management through the emergency department (ED) and commonly have a long hospital stay due to the lack of a dedicated methodology for evaluation and management, particularly in patients who present with visual loss (i.e., fulminant IIH). An innovative practice approach is needed to improve the means of multidisciplinary communication in care and evaluation of IIH patients. This paper aims to discuss the need for the development and implementation of a multidisciplinary "fast-track" strategy for the evaluation and management of patients with fulminant IIH or those with a suboptimal response to maximum tolerated medical treatment at risk for visual loss. We suggest that such a program could reduce hospital stay and ED visits and therefore reduce healthcare costs and improve patient outcomes by accelerating the management process.

Papilledema and Anemia: A Rare Association

Papilledema is the swelling of the optic disc due to the transmission of intracranial pressure through the optic nerve. It can occur as a symptom of various intracranial pathologies that elevate the intracranial pressure. Even though anemia has been described as an association with raised intracranial pressure, the exact causal relationship between the two has not been well established in the literature. We present one such unusual case wherein a 21-year-old female patient, who complained of headaches, was found to have papilledema and severe anemia. After an unyielding workup for secondary causes, the rare association between papilledema and anemia was considered and prompt hemoglobin correction was ensued. Subsequently, resolution of papilledema and improvement in the visual acuity of the patient was observed. Although the causal relationship between anemia and papilledema has not been thoroughly explained, appropriate workup and correction of anemia play an integral role in the management of patients with papilledema and the prevention of long-term ocular complications.

Optic Disc Edema and Elevated Intracranial Pressure (ICP): A Comprehensive Review of Papilledema

Papilledema is a swelling of the optic disc secondary to elevated intracranial pressure (ICP). We analyzed 79 peer-review journal articles and provided a concise summary of the etiology, epidemiology, pathophysiology, clinical presentation, evaluation, natural history, differential diagnosis, treatment, and prognosis of papilledema. Only studies written in English with the full text available were included. Although many etiologies of papilledema exist, idiopathic intracranial hypertension is the most common and, thus, a large focus of this review.