Drug-Induced Intracranial Hypertension: A Systematic Review and Critical Assessment of Drug-Induced Causes

Risk factors and disease associations in people living with idiopathic intracranial hypertension

INTRODUCTION

Idiopathic intracranial hypertension is a neurological condition characterized by a raised intracranial pressure and papilledema, leading to chronic headaches and visual disturbances. By recognizing modifiable risk factors and deploying evidence-based interventions, healthcare providers have the potential to mitigate the burden of the disease and improve patient outcomes.

AREAS COVERED

It is well known that the condition occurs in predominantly pre-menopausal females who live with obesity particularly in the context of recent weight gain. This review discusses what risk factors may contribute to the metabolic underpinnings of cerebrospinal fluid dysregulation. There are a number of disease associations that are important to screen for as they can alter management.

EXPERT OPINION

There is emerging evidence to suggest that idiopathic intracranial hypertension is a systemic metabolic disease and it is unknown what are all the risk factors are that precipitate the condition. Targeting certain hardwired risk factors is unachievable. However, as recent weight gain has been identified as a predominant risk factor for the development of the disease and relapse, modification of body weight should be the primary aim of management. Insightful research into the involvement of the neuroendocrine axis driving cerebrospinal fluid dysregulation now has the potential for the development of therapeutic targets.

Case Commentary: Dual β-lactam as part of regimen to treat Mycobacterium abscessus lung disease

Individuals with compromised lung function and immunity are susceptible to developing chronic Mycobacterium abscessus infection. Current treatment recommendations typically involve using one β-lactam antibiotic in combination with non-β-lactam antibiotics. However, a recent case study (B. Becken, K. M. Dousa, J. L. Johnson, S. M. Holland, and R. A. Bonomo, Antimicrob Agents Chemother 68:e00319-24, 2024, https://doi.org/10.1128/aac.00319-24) demonstrated successful treatment of chronic M. abscessus lung disease in a child using two β-lactam antibiotics simultaneously. This commentary reviews the emerging evidence and outstanding questions regarding dual β-lactam therapy for M. abscessus infections.

Risks and benefits of clozapine and lithium co-prescribing: A systematic review and expert recommendations

OBJECTIVES

To identify the risks and benefits of clozapine‑lithium co-prescription.

METHODS

Articles published in English or French were identified with a MEDLINE, Web of Sciences and PsycINFO search, from inception through January 2023, using the term 'clozapine' in combination with 'lithium'. Data were synthesized narratively.

RESULTS

Of the 67 articles included in the review, more than half (n = 38, 56.7 %) were focused on clozapine-related blood dyscrasia. A body of evidence drawn from case reports and retrospective chart studies highlights the potential benefits of lithium prescription for clozapine-related neutropenia, since this strategy may avoid clozapine discontinuation or allow its rechallenge. The most documented adverse drug reactions (ADRs) associated with clozapine‑lithium co-prescription are neurotoxic events, which may be prevented or detected early by clinical, electroencephalographic and therapeutic drug monitoring. Causality assessment cannot be established for other reported ADRs occurring during clozapine‑lithium co-prescription. The benefits of the combined prescription on psychotic and/or mood symptoms are poorly documented.

CONCLUSION

The risks and benefits of clozapine‑lithium co-prescription require further exploration as the combination might significantly contribute to reducing underprescription or premature discontinuation of clozapine.

Managing idiopathic intracranial hypertension in the eye clinic

Idiopathic intracranial hypertension (IIH) is a neuro-ophthalmological condition characterised by a raised intracranial pressure and papilloedema that causes disabling headaches. The main risk factors of female sex and living with obesity have been known for some time, however the knowledge of the underlying pathophysiology is evolving. Papilloedema can impact the visual function, and the majority of people are offered acetazolamide. Those with sight threatening disease need urgent management, though there is little high quality evidence to recommend any particular surgical intervention. Headache treatment is an unmet clinical need and simple medication overuse advice has the potential to reduce the chronification of migraine-like headaches. IIH is emerging as a systemic metabolic disease distinct from people living with obesity alone. While weight loss is the main stay of disease modifying therapy this is challenging to access and many healthcare professionals that manage the condition have no formal training or accessible pathways for weight management. The aim of this "how to do it" article is to present the latest advances in knowledge of IIH that we pragmatically included in routine clinical care for people living with the condition.

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.

Headache and Other Factors Modifying Cerebrospinal Fluid Opening Pressure in Pediatric Patients

Cerebrospinal fluid opening pressure values are associated with various neurologic diseases; however, numerous factors can modify this measurement. This study aims to describe factors related to modifications in opening pressure measurements in pediatric patients. Methods: A retrospective analysis of lumbar punctures in pediatric patients conducted by the neuropediatrics group with institutional standardization. Bivariate and linear regression analyses were performed to determine the association between opening pressure and variables included in the study. Results: 544 events, median age 107 months, median opening pressure 19.7 cm H2O. Bivariate analysis found no association with medication use; anesthetics that increased opening pressure were remifentanil (P = .02) and propofol (P = .05), along with a positive linear correlation between opening pressure and age (P < .0001). Multiple linear regression analysis revealed that age, BMI, male gender, and remifentanil use were associated with an increase in opening pressure, whereas corticosteroid withdrawal was associated with a reduction in opening pressure. There is an interaction between age and headache, with an association with increased opening pressure up to around 140 months. Conclusion: This study identifies factors associated with changes in opening pressure, crucial for estimating normal opening pressure values in children. Headaches, anesthetic use, and corticosteroid withdrawal are confirmed as significant factors.

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.

Antibiotics-Induced Intracranial Hypertension: A Case Report With Literature Review

Idiopathic intracranial hypertension (IIH) is a rare condition characterized by increased intracranial pressure, with an unknown cause. However, the pathophysiology of antibiotic-induced IIH remains unclear. The clinical symptoms include headache, visual disturbances, and vomiting. The diagnosis is confirmed by an elevated intracranial pressure (ICP) with normal CSF study and cerebral imaging. Management includes discontinuing the offending antibiotic and reducing ICP with medications such as acetazolamide or diuretics. Therefore, surgical intervention may be necessary in severe cases. In this article, we report the case of a 19-year-old patient, admitted with symptoms of intracranial hypertension syndrome, occurring three days after receiving antibiotics (gentamicin, penicillin). Physical examination revealed bilateral optic disc edema. Cerebral magnetic resonance imaging (MRI) revealed indirect signs of intracranial hypertension. The CSF pressure measurement was approximately 290 mmHg, while CSF and other laboratory blood tests were normal. The patient received methylprednisolone bolus and topiramate (50 mg/day). A month later, the clinical outcome showed regression of headaches and regression of the papilledema.

Doxycycline-Induced Intracranial Hypertension Presenting as Unilateral Pulsatile Tinnitus

Background

Pulsatile tinnitus (PT) is increasingly recognized as a cardinal symptom of idiopathic intracranial hypertension (IIH). However, clinicians should remain aware of other causes of nonidiopathic or secondary intracranial hypertension manifesting as PT. We present 2 patients with isolated PT (without accompanying headache, blurred vision, and papilledema) thought to be secondary to tetracycline-induced intracranial hypertension. To our knowledge, these are the first cases of PT as the presenting symptom of this condition.

Cases

A 41-year-old female (body mass index [BMI] 29 kg/m2) with ocular rosacea was initially treated with minocycline. Shortly after transitioning to oral doxycycline and erythromycin eye ointment, she noted left-sided PT. Her PT resolved after discontinuing doxycycline. In a second case, a 39-year-old female (BMI 19 kg/m2) with acne presented with a three-year history of left-sided PT while on long-term oral doxycycline for many years. She denied visual or auditory changes and atypical headaches. MRI findings were concerning for intracranial hypertension. Three months later, the patient was seen by neuro-ophthalmology, with findings suggesting prior papilledema. The patient reported PT improvement after discontinuing doxycycline.

Conclusions

This case series highlights 2 cases of isolated PT as the sole symptom of intracranial hypertension that resolved with tetracycline cessation. The presentation and unexpected improvement following tetracycline discontinuation are atypical compared with previous reports of tetracycline-induced intracranial hypertension. Clinicians should maintain a high index of suspicion for all types of intracranial hypertension (idiopathic and secondary), even in patients with a lower BMI. Current and prior medications should be reviewed when considering the etiology of intracranial hypertension.

Optic Disc Swelling in Cancer Patients: Etiology and Implications

PURPOSE

To analyze the etiology and implications of optic disc swelling in cancer patients treated at a specialized tertiary cancer center in Jordan.

METHODS

This was a retrospective study of all cancer patients who had optic disc swelling between January 2019 and December 2020 at King Hussein Cancer Center (KHCC). Patients' data included age, sex, laterality, visual acuity, and the underlying cause and management for the optic disc swelling.

RESULTS

Optic disc swelling was present in 58 cancer patients (96 eyes), with 38 (65%) having bilateral involvement. Among these, 33 (57%) were female, and 43 (74%) were ≤40 years old. At diagnosis, 58 (63%) eyes had a best-corrected visual acuity (BCVA) better than 0.5, improving to 73 (76%) eyes at the last follow-up. High intracranial pressure (ICP) was the most common primary cause (30 patients/52%), followed by tumor infiltration of the optic nerve (10 patients/17%), optic nerve compression (7 patients/12%), and optic nerve inflammation (5 patients/9%). Four patients had pseudopapilledema. Among the 30 patients with high ICP, CNS tumors were predominant (21 patients/70%), with only 3 having idiopathic intracranial hypertension. Medications, including ATRA (All-Trans Retinoic Acid) and systemic steroids, contributed to increased ICP in six patients (20%). BCVA was less than 0.5 in all eyes (100%) affected by tumor infiltration, optic nerve inflammation, and ischemic optic neuropathy, while only eight eyes (14%) with optic disc swelling due to elevated ICP had a BCVA less than 0.5 (p < 0.0001). Management included steroids (53 patients/91%), acetazolamide (30 patients/52%), chemotherapy (20 patients/34%), radiation therapy (13 patients/22%), frequent lumbar punctures (12 patients/21%), and surgery (28 patients/48%). Visual acuity improved in 40 eyes (42%), with only 4 eyes (4%) experiencing deterioration. At a 12-month median follow-up period, 11 (19%) patients were dead, 10 (10%) eyes had poor vision (BCVA less than 0.1), and 21 (22%) eyes had BCVA 0.5 or better.

CONCLUSIONS

Various underlying pathologies can induce optic disc swelling in cancer patients, a grave condition capable of causing vision loss. Notably, tumor infiltration of the optic nerve tends to result in more profound visual impairment compared to papilledema due to elevated ICP. Timely detection is crucial, and immediate symptomatic treatment followed by addressing the underlying cause is essential to prevent irreversible optic nerve damage and vision loss in cancer patients.

Treatment of mild to severe acne with 1726 nm laser: A safe alternative to traditional acne therapies

INTRODUCTION

Acne is the most common reason for dermatology consultation in adolescents and young adults. Consultation is often delayed despite unsuccessful self-treatment. Postponing effective treatment places acne sufferers at higher risk for permanent acne scars and post-inflammatory pigment changes.

AIM

This review discusses clinical challenges with present therapeutic options for acne treatment and the role of a 1726 nm laser for acne.

METHODS

Current acne treatment guidelines were reviewed. A literature review was conducted for trials of light-based acne therapy. The selectivity of previous light-based therapies was reviewed.

RESULTS

Available acne therapy is effective, but treatment-related side effects are common. Acne treatment guidelines do not include recommendations for light-based treatments. Different types of light-based treatments have been tried but until now no wavelength specifically targeted sebaceous glands.

CONCLUSION

The 1726 nm laser is safe and effective for treating mild to severe acne in all Fitzpatrick skin types. Acne resolution is apparent within the first month and improves for up to 2 years beyond treatment.

Targeted Treatment of Diseases of Immune Dysregulation

Increasing molecular knowledge of autoinflammatory and autoimmune disorders has enabled more targeted treatment of these conditions. Treatment of inflammasomopathies is often aimed at interleukin-1 (IL-1) blockade, with potential use of other inhibitors targeting cytokines such as IL-18 and IL-6. Interferonopathies and some disorders with overlap features of autoimmunity and autoinflammation may improve with Janus kinase inhibition. Autoimmune conditions may also respond to inhibition of different cytokines, as well as to inhibition of T and B lymphocytes. Effective treatment is increasingly possible through targeted/precision medicine approaches.

Efficacy of Minocycline for the Treatment of Mycoplasma genitalium

Background

High levels of macrolide resistance and increasing fluoroquinolone resistance are making Mycoplasma genitalium increasingly difficult to treat. Minocycline is an alternative treatment for patients with macrolide-resistant M genitalium infections that have failed moxifloxacin, or for those with fluoroquinolone contraindications or resistance. Published efficacy data for minocycline for M genitalium are limited.

Methods

We evaluated minocycline 100 mg twice daily for 14 days at Melbourne Sexual Health Centre (MSHC). Microbial cure was defined as a negative test of cure within 14-90 days after completing minocycline. The proportion cured and 95% confidence intervals (CIs) were calculated, and logistic regression was used to explore factors associated with treatment failure. We pooled data from the current study with a prior adjacent case series of patients with M genitalium who had received minocycline 100 mg twice daily for 14 days at MSHC.

Results

Minocycline cured 60 of 90 (67% [95% CI, 56%-76%]) infections. Adherence was high (96%) and side effects were mild and self-limiting. No demographic or clinical characteristics were associated with minocycline failure in regression analyses. In the pooled analyses of 123 patients, 83 (68% [95% CI, 58%-76%]) were cured following minocycline.

Conclusions

Minocycline cured 68% of macrolide-resistant M genitalium infections. These data provide tighter precision around the efficacy of minocycline for macrolide-resistant M genitalium and show that it is a well-tolerated regimen. With high levels of macrolide resistance, increasing fluoroquinolone resistance, and the high cost of moxifloxacin, access to nonquinolone options such as minocycline is increasingly important for the clinical management of M genitalium.

Idiopathic De Novo Arteriovenous Malformation: A Rare Acquired Intracranial Lesion

The de novo development of cerebral arteriovenous malformations (AVMs) in adults is an exceedingly rare event that has prompted the theory that a "second hit" is required to induce AVM formation. The authors document development of an occipital AVM in an adult a decade and a half after a brain magnetic resonance imaging (MRI) disclosed no abnormality. A 31-year-old male with a family history of AVMs and a 14-year history of migraines with visual auras and seizures presented to our service. Because of the onset of a first seizure and migraine headaches at age 17, the patient underwent high-resolution MRI that showed no intracranial lesion. After 14 years of progressively worsening symptoms, he underwent a repeat MRI that demonstrated a new de novo Spetzler-Martin grade 3 left occipital AVM. The patient received anticonvulsants and underwent Gamma Knife radiosurgery for his AVM. This case suggests that patients with seizures or persistent migraine headaches should have periodic repeat neuroimaging to exclude the development of a vascular cause despite an initial negative MRI.

"Idiopathic" intracranial hypertension: An update from neurointerventional research for clinicians

BACKGROUND

The recognition of venous sinus stenosis as a contributing factor in the majority of patients with idiopathic intracranial hypertension coupled with increasing cerebral venography and venous sinus stenting experience have dramatically improved our understanding of the pathophysiologic mechanisms driving this disease. There is now a dense, growing body of research in the neurointerventional literature detailing anatomical and physiological mechanisms of disease which has not been widely disseminated among clinicians.

METHODS

A literature search was conducted, covering the most recent neurointerventional literature on idiopathic intracranial hypertension, the pathophysiology of idiopathic intracranial hypertension, and management strategies (including venous sinus stenting), and subsequently summarized to provide a comprehensive review of the most recently published studies on idiopathic intracranial hypertension pathophysiology and management.

CONCLUSION

Recent studies in the neurointerventional literature have greatly improved our understanding of the pathophysiologic mechanisms causing idiopathic intracranial hypertension and its associated conditions. The ability to make individualized, patient-specific treatment approaches has been made possible by advances in our understanding of how venous sinus stenosis and cerebral venous hypertension fundamentally contribute to idiopathic intracranial hypertension.

Truncal Acne and Scarring: A Comprehensive Review of Current Medical and Cosmetic Approaches to Treatment and Patient Management

Acne vulgaris is one of the most common skin disorders worldwide. It typically affects skin areas with a high density of sebaceous glands such as the face, upper arms, chest, and/or back. Historically, the majority of research efforts have focused on facial acne vulgaris, even though approximately half of patients with facial lesions demonstrate truncal involvement. Truncal acne vulgaris is challenging to treat and poses a significant psychosocial burden on patients. Despite these characteristics, studies specifically examining truncal acne vulgaris are limited, with treatment guidelines largely derived from facial protocols. Therefore, truncal acne remains an understudied clinical problem. Here, we provide a clinically focused review on the epidemiology, evaluation, and available treatment options for truncal acne vulgaris. In doing so, we highlight knowledge gaps with the goal of spurring further investigation into the management of truncal acne vulgaris.

Increased cerebrospinal fluid pressure and nephrotic syndrome: A case report and literature review

OBJECTIVE

To analyze how nephrotic syndrome (NS) correlates to increased intracranial pressure (ICP), and to present a case of an adult patient whose initial manifestation of NS was cephalalgia, with the later identification of raised ICP.

METHODS

Data were retrospectively retrieved from the patient's record, and a literature search with the keywords "nephrotic syndrome", "intracranial hypertension" and "headache" was conducted in PubMed and Embase.

RESULTS

This is a rare description of co-occurrence of NS and raised ICP in a 48-year-old man, in which ICP normalizes after NS remits. There is no known cause for the raised ICP of our patient. Ten reports (n = 13) of concomitant occurrence of increased ICP and NS were described in the literature, both in children and adults. Cerebral venous thrombosis (CVT) was the most likely underlying cause for the majority of them. For one patient, the underlying cause was meningoencephalitis. Finally, in one case, the cause is unknown, but CVT was not discarded.

CONCLUSION

The early suspicion of elevated ICP is warranted in patients with new-onset headache and NS. It is possible that NS could both directly and indirectly lead to increased ICP through yet unknown mechanisms, although this direct causal relationship cannot be currently established.

Expanding the clinical spectrum of idiopathic intracranial hypertension

PURPOSE OF REVIEW

Idiopathic intracranial hypertension (IIH) is a disorder of raised intracranial pressure (ICP). Although the majority of patients with IIH present classically with headache and papilledema, some patients may have unusual presentations or manifestations. Recent advancements in neuroimaging have facilitated the identification of other presentations associated with IIH. This review provides an overview of the expanding clinical spectrum of IIH.

RECENT FINDINGS

Presentations of IIH that are considered unusual include highly asymmetric or unilateral papilledema, IIH without papilledema, and IIH associated with cranial nerve involvement. These presentations likely reflect differences in the way cerebrospinal fluid (CSF) pressure is transmitted intracranially. Radiological signs of intracranial hypertension are increasingly recognized in patients with IIH and provide further insights into the effects of raised ICP on intracranial structures. Osseous changes in the skull base leading to formation of meningoceles and encephaloceles have been identified in patients with IIH, spontaneous skull base CSF leak, and drug-resistant temporal lobe epilepsy, suggesting a possible association.

SUMMARY

Clinicians should be familiar with the expanding clinical spectrum of IIH and the implications for the management of these presentations.

[Idiopathic intracranial hypertension: From physiopathological mechanisms to therapeutic decision]

Clinical features include visual disturbances, headaches, and pulsatile tinnitus that can be associated with reduced quality of life, and a risk of irreversible visual impairment in some cases. Obese women of childbearing age represent the main at-risk population, and the incidence of the disease is increasing because of rising prevalence of obesity worldwide. In addition, an imbalance in sex hormones is reported as a contributing risk factor. The pathophysiology of idiopathic intracranial hypertension involves a disturbance of the evacuation pathway of intracranial fluids caused by the increase in intracranial venous pressure. Brain imaging is useful for diagnosis with several signs including bilateral stenosis of the transverse sinuses that plays a major role in the pathogenesis of the disease by creating a positive feedback loop that increases intracranial venous hypertension and contributes to clinical manifestations. Treatment aims to relieve symptoms and prevent permanent visual impairment. Drug therapies including acetazolamide and topiramate have moderate effectiveness. Among invasive treatments, transverse sinus stenting seems to be the most interesting option to consider in drug-resistant patients. Weight loss remains essential to achieve a sustainable improvement by reducing central venous pressure. Future randomized trials are expected to reach a consensus on this treatment.

Phenotyping non-idiopathic pseudotumor cerebri syndrome - A prospective cohort study

OBJECTIVE

To identify the most frequent causes of secondary pseudotumor cerebri syndrome and compare phenotype, clinical presentation, and symptoms of secondary pseudotumor cerebri syndrome to the primary form of pseudotumor cerebri syndrome, idiopathic intracranial hypertension.

METHODS

The study was a prospective cohort study including patients with new-onset pseudotumor cerebri syndrome. Diagnostic work up was standardized. Patients were diagnosed with secondary pseudotumor cerebri syndrome or idiopathic intracranial hypertension according to the revised Friedman criteria. Secondary pseudotumor cerebri syndrome patients were categorized into five causes: medication, systemic causes, sleep apnea, cerebrovascular causes, and several competing causes. Phenotype, clinical presentation, symptoms and neuroimaging were compared between groups.

RESULTS

Out of 278 cases, 28 secondary pseudotumor cerebri syndrome and 120 idiopathic intracranial hypertension patients were included. The most frequent causes of secondary pseudotumor cerebri syndrome were medication (n  =  8, 28.6%) and systemic causes (n = 8, 28.6%), followed by sleep apnea (n = 5, 17.9%), cerebrovascular causes (n = 4, 14.3%) and several competing causes (n = 3, 10.7%). Secondary pseudotumor cerebri syndrome and idiopathic intracranial hypertension patients were phenotypically alike and predominately female, premenopausal, and obese. Symptoms and objective findings at disease onset were similar between groups.

CONCLUSION

Secondary pseudotumor cerebri syndrome should be considered in all patients with suspected pseudotumor cerebri syndrome as secondary pseudotumor cerebri syndrome and idiopathic intracranial hypertension patients are phenotypically and clinically alike. A thorough diagnostic workup is needed as treatment of idiopathic intracranial hypertension and secondary pseudotumor cerebri syndrome is markedly different.

Tetracyclines-An Important Therapeutic Tool for Dermatologists

Tetracyclines are a group of antibiotics whose first representative was discovered over 70 years ago. Since then, they have been of great interest in dermatology. In addition to their antibacterial activity, they are able to inhibit metalloproteinases and exhibit anti-inflammatory, anti-apoptotic and antioxidant effects. The side effects have been thoroughly studied over the years, the most characteristic and important ones in daily dermatological practice being: phototoxicity, hyperpigmentation, onycholysis, photoonycholysis, induced lupus erythematosus, and idiopathic intracranial hypertension. In this article, we summarize the use of tetracyclines in infectious diseases and inflammatory dermatoses, and further discuss the instances where the efficacy and safety of tetracyclines have been highlighted over the past few years.

Idiopathic Intracranial Hypertension: A Comprehensive Overview

Idiopathic intracranial hypertension (IIH), also called pseudotumor cerebri syndrome, is a disorder defined as elevated intracranial pressure (ICP) of unknown cause. It is a diagnosis of exclusion in most cases, and all other forms of elevated ICP must be ruled out. With its increasing prevalence, it is much more likely for physicians, otolaryngologists included, to encounter this condition. It is important to have a clear understanding of the typical and atypical presentation of this disease, along with its evaluative workup and management options. This article reviews IIH with a focus on those factors that are specifically relevant to otolaryngologic care.

Intracranial hypertension and empty Sella from adrenal adenoma and excessive and prolonged steroid usage: a case report

BACKGROUND

There is only one documented case of intracranial hypertension (IH) and empty sella from cortisol-producing adrenal adenoma so far. And IH and empty sella caused by long-term exogenous hypercortisolism has never been reported before. The purpose of this case report is to alert clinicians to glucocorticoid-induced IH.

CASE PRESENTATION

We present retrospectively a 50-year-old woman with cortisol-secreting adrenal adenoma, who progressed to intractable intracranial hypertension and a markedly expanded empty sella due to improper treatment. In 2011, the patient presented with hypertension, lack of cortisol circadian rhythm, low ACTH, a left adrenal adenoma and a partial empty sella, but did not receive low-dose dexamethasone suppression test (LDDST) and 24-h urinary cortisol. In 2014, she exhibited truncal obesity, raised cortisol, LDDST non-suppression, high urinary free cortisol and low ACTH, proving her cortisol-producing adrenal adenoma. She was simultaneously diagnosed with unexplained IH because of papilledema and elevated intracranial pressure, and her partial empty sella changed to a complete empty sella. In 2015, she underwent adrenal adenoma resection. From 2015 to 2018, she kept taking dexamethasone at least 2 mg daily without her doctors' consent. During this period, she developed transient cerebrospinal fluid rhinorrhea, and her empty sella further worsened. After switching to low dose hydrocortisone, her papilledema disappeared completely, but optic atrophy has become irreversible.

CONCLUSIONS

The patient seems to be just an extreme case, but it may reveal and illustrate a general phenomenon: Both cortisol-producing adrenal adenoma and long-term exogenous hypercortisolism could cause varying degrees of elevated intracranial pressure and empty sella. Clinicians should remain vigilant for this phenomenon in patients with cortisol-producing adrenal adenoma or excessive and prolonged steroid usage and give them corresponding examinations to identify this complication.

Papilledema: A review of etiology, pathophysiology, diagnosis, and management

Papilledema is optic nerve head edema secondary to raised intracranial pressure (ICP). It is distinct from other causes of optic disk edema in that visual function is usually normal in the acute phase. Papilledema is caused by transmission of elevated ICP to the subarachnoid space surrounding the optic nerve that hinders axoplasmic transport within ganglion cell axons. There is ongoing controversy as to whether axoplasmic flow stasis is produced by physical compression of axons or microvascular ischemia. The most common cause of papilledema, especially in patients under the age of 50, is idiopathic intracranial hypertension (IIH); however, conditions that decrease cerebrospinal fluid (CSF) outflow by either causing CSF derangements or mechanically blocking CSF outflow channels, and rarely conditions that increase CSF production, can be the culprit. When papilledema is suspected clinically, blood pressure should be measured, and pseudopapilledema should be ruled out. Magnetic resonance imaging of the brain and orbits with venography sequences is the preferred neuroimaging modality that should be performed next to look for indirect imaging signs of increased ICP and to rule out nonidiopathic causes. Lumbar puncture with measurement of opening pressure and evaluation of CSF composition should then be performed. In patients not in a typical demographic group for IIH, further investigations should be conducted to assess for underlying causes of increased ICP. Magnetic resonance imaging of the neck and spine, magnetic resonance angiography of the brain, computed tomography of the chest, complete blood count, and creatinine testing should be able to identify most secondary causes of intracranial hypertension. Treatment for patients with papilledema should be targeted toward the underlying etiology. Most patients with IIH respond to weight loss and oral acetazolamide. For patients with decreased central acuity and constricted visual fields at presentation, as well as patients who do not respond to treatment with acetazolamide, surgical treatments should be considered, with ventriculoperitoneal shunting being the typical procedure of choice.

A national Swedish case-control study investigating incidence and factors associated with idiopathic intracranial hypertension

OBJECTIVE

To study the incidence of idiopathic intracranial hypertension in Sweden and to explore whether previously proposed risk factors are associated with idiopathic intracranial hypertension by investigating the odds of exposure one year prior to diagnosis in patients compared to controls.

METHODS

Using Swedish health care registers and validated diagnostic algorithms, idiopathic intracranial hypertension patients diagnosed between 2000-2016 were compared with randomly selected matched controls, five from the general population and five with obesity.

RESULTS

We identified 902 idiopathic intracranial hypertension patients and 4510 matched individuals in each control group. Mean incidence among inhabitants ≥18 years of age was 0.71 per 100,000; rising from 0.53 in 2000-2005 to 0.95 in 2012-2016. There were increased odds for idiopathic intracranial hypertension patients compared to general population for exposure to: kidney failure (odds ratio =13.2 (4.1-42.0)), arterial hypertension (odds ratio =17.5 (10.5-29.3)), systemic lupus erythematosus (odds ratio =13.8 (4.3-44.7)), tetracyclines, sulphonamides, lithium, and corticosteroids. In obese controls, odds ratios were also significantly increased for these exposures. Hormonal contraceptive use and exposure to pregnancy did not appear to be associated factors for idiopathic intracranial hypertension development.

CONCLUSIONS

The incidence of idiopathic intracranial hypertension in Sweden is lower relative to reports from other countries but is on the rise. This case-control study confirms several previously reported risk factors associated with idiopathic intracranial hypertension.

Intracranial hypertension associated with topical tretinoin use

Purpose

To report cross-reactivity between topical vitamin A derivatives and tetracycline-class antibiotics.

Observations

A 19-year old woman with a remote history of resolved secondary intracranial hypertension due to minocycline use developed intracranial hypertension while using topical tretinoin alone. Examination demonstrated bilateral optic nerve edema, a right sixth cranial nerve palsy, along with characteristic features of markedly elevated intracranial pressure on imaging. Lumbar puncture opening pressure was 60 cmH₂O. Cessation of topical tretinoin use ensued complete resolution of symptoms and optic nerve swelling in both eyes.

Conclusions and importance

Our findings substantiate the need to avoid topical vitamin A derivatives and alternate drug classes known to be associated with drug-induced intracranial hypertension.

Clinical Characteristics of Idiopathic Intracranial Hypertension in Patients Over 50 Years of Age: A multicenter clinical cohort study

PURPOSE

To characterize the clinical features of idiopathic intracranial hypertension (IIH) in patients >50 years of age compared to the typical IIH population and existing data for this older cohort.

DESIGN

Retrospective, clinical cohort study.

METHODS

Medical records of 65 patients >50 years of age at first diagnosis of IIH were reviewed based on the Modified Dandy Criteria from 4 academic centers. Each center provided randomly selected controls from IIH patients <50 years of age for each study patient at their location. Data recorded included patient demographics, presenting symptoms, medications, coexisting medical conditions, cerebrospinal fluid (CSF) opening pressure, treatments, and neuro-ophthalmic data from initial and final visits.

RESULTS

Compared to controls, the older cohort showed the following characteristics: fewer females (n = 51 [78.5%] vs. controls: n = 60 [92.3%]; P = .045), fewer headaches (n = 33 [50.8%] vs. controls: 52 [80.0%]; P = .001), more frequent incidental discoveries of papilledema (n = 19 [29.2%] vs. controls: 7 [10.8%]; P = .015), and lower CSF opening pressure [median: 33 cm H₂O [range: 21-58 cm H₂O] vs. the median for controls: 34 cm H₂O [range: 24-67 cm H₂O; P = .029).

CONCLUSIONS

Patients with IIH diagnosed at >50 years of age were less often female and had lower CSF opening pressure, fewer headaches, a higher chance of incidentally identified papilledema, and body mass index similar to that of younger IIH patients. Older IIH onset was not associated with worse visual outcome.

Idiopathic intracranial hypertension and visual function in North Indian population

BACKGROUND

Idiopathic Intracranial Hypertension (IIH) is a neurological disorder with varied presentation, visual morbidity being the most important one. Literature is sparse as regards the effects of IIH on the visual system in Asians.

OBJECTIVE

Assessment of visual morbidity and change with treatment in IIH patients in North India through a prospective interventional study.

MATERIALS AND METHODS

Sixty eyes of newly diagnosed IIH patients were evaluated for functional and structural tests of visual system. Lumbar puncture was performed to establish IIH diagnosis and received oral Carbonic anhydrase inhibitor thereafter. Change in visual function was studied from baseline to 6-month follow-up visit.

RESULTS

Mean age of participants at presentation was 33.27 ± 10.68 years and majority were females (73.3%). Seventy percent eyes (n = 42) had visual acuity 20/20 at presentation. Average Pelli Robson contrast sensitivity (CS) improved from 1.86 ± 0.34 to 2.11 ± 0.24 (Friedman Test: X2 = 59.2, p ⩽ 0.001) while number of eyes with detectable visual field deficits reduced from 70% to 43.7%. Retinal nerve fibre layer (RNFL) thickness reduced from 176.27 to 114.97 µ (Friedman Test: X2 = 69.3, p ⩽ 0.001).

CONCLUSIONS

The socio-demographic profile in our study showed higher male incidence than noted in previous studies. Visual function deficits were present in patients, even in those with 20/20 visual acuity. Significant improvement was seen after lumbar puncture and initiation of medical treatment. CS and RNFL thickness showed significant improvement even after 1 month of treatment and can be used for monitoring IIH patients.

Etiology, pathogenesis and management of idiopathic intracranial hypertension, and role of optic canal size in asymmetric papilledema: A review

Idiopathic intracranial hypertension (IIH) is characterized by raised intracranial pressure of unknown origin that primarily afflicts obese women of childbearing age. There are several treatment options, but currently there are none that are effective for the entire affected population. The lack of a universally effective treatment is related to an incomplete understanding of the etiology of the condition and the lack of a well-defined pathophysiological mechanism for the disease process. Classically, IIH has been thought of as a diagnosis of exclusion once radiographical imaging has ruled out all other causes of elevated intracranial pressure. Today, we know that imaging does capture subtle changes, and might provide keys to finally understand the pathogenesis of IIH so that a definitive treatment can be discovered or developed. Recently, advancements in radiography, optical coherence tomography, and electroretinography have shown promise for the future of IIH evaluation. A topic within IIH imaging that has recently sparked interest is the possibility that the severity of papilledema may have an association with the size of the optic canal. In this article, we also discuss the recent studies on the relationship between asymmetric papilledema and optic canal size.

Fulminant intracranial hypertension secondary to oxytetracycline requiring urgent ventriculo-peritoneal shunt insertion

Idiopathic intracranial hypertension is a syndrome that presents with headaches and visual loss. Its pathogenesis is unknown. Treatment options include acetazolamide, therapeutic lumbar punctures or permanent CSF diversion. We present the only reported case of acute drug-induced intracranial hypertension secondary to oxytetracycline requiring urgent cerebrospinal fluid diversion. The patient's rapid visual failure progressed daily despite discontinuation of the drug and required an urgent ventriculo-peritoneal (VP) shunt insertion. Patients should be counselled about the rare potential risk of developing intracranial hypertension when commencing oxytetracycline. Rapid visual failure in IIH is a neurosurgical emergency necessitating urgent ventriculoperitoneal shunt insertion.