[Idiopathic intracranial hypertension. Review of our experience in the last eight years (2016-2023)]. / Hipertensión intracraneal idiopática. Revisión de nuestra experiencia en los últimos ocho años (2016-2023).

INTRODUCTION: Idiopathic intracranial hypertension (IIH) or benign intracranial hypertension is a rare disease in childhood. The clinical presentation in pediatric patients can be very variable, being more unespecific in younger patients. PATIENTS AND METHODS: A retrospective descriptive study was carried out on patients diagnosed of IIH in the last eight years (2016-2023) in the neuropediatrics unit of a tertiary hospital. In the present study, the clinical-epidemiological characteristics and the diagnostic-therapeutic procedure carried out in each case were analyzed. RESULTS: We studied 14 patients, 57% were women. The average age at diagnosis was 9 years, headache was the most common reason for consultation. In all patients, papilledema was found in the fundus and neuroimaging didn´t find alterations. Optical coherence tomography has been carried out in 78.5% of the sample, > 80% of patients showed thickening of the retinal nerve fiber layer. All patients had a high cerebrospinal fluid opening pressure (>25 cmH2O). 57% of patients required treatment with acetazolamide, a carbonic anhydrase inhibito. In all patients the resolution was complete, however almost 30% of them have presented recurrences during follow-up. CONCLUSIONS: In recent years there has been an increase in the incidence of this entity, making early diagnosis and treatment essential to avoid possible irreversible damage.

TITLE: Hipertensión intracraneal idiopática. Revisión de nuestra experiencia en los últimos ocho años (2016-2023).Introducción. La hipertensión intracraneal idiopática (HII), o hipertensión intracraneal benigna, es una enfermedad poco frecuente en la infancia. La presentación clínica en pacientes pediátricos puede ser muy variable, y es más inespecífica a menor edad. Pacientes y métodos. Se ha realizado un estudio descriptivo retrospectivo de los pacientes diagnosticados de HII en los últimos ocho años (2016-2023) en la consulta de neuropediatría de un hospital de tercer nivel. En el presente estudio se analizaron las características clinicoepidemiológicas y el procedimiento diagnosticoterapéutico llevado a cabo en cada caso. Resultados. Se estudió a 14 pacientes, de los cuales el 57% eran mujeres. La edad media en el momento del diagnóstico fue de 9 años, y la cefalea fue el motivo de consulta más habitual. En todos los pacientes se constató papiledema en el fondo de ojo y una prueba de neuroimagen sin alteraciones. Se llevó a cabo una tomografía de coherencia óptica en el 78,5% de la muestra, y >80% de los pacientes presentaba engrosamiento de la capa de fibras nerviosas retiniana. La totalidad de los pacientes presentaba una presión de apertura de líquido cefalorraquídeo elevada (> 25 cmH2O). El 57% de los pacientes precisó como tratamiento acetazolamida, un inhibidor de la anhidrasa carbónica. En todos los pacientes la resolución fue completa; sin embargo, casi el 30% de ellos presentó recurrencias durante el seguimiento. Conclusiones. En los últimos años se ha mostrado un aumento en la incidencia de esta entidad, y es fundamental un diagnóstico y un tratamiento precoces para evitar posibles secuelas irreversibles.

Clinical profile and treatment outcomes of idiopathic intracranial hypertension: a multicenter study from Korea.

BACKGROUND: Currently, there is a relative lack of detailed reports regarding clinical presentation and outcome of idiopathic intracranial hypertension in Asians. This study aims to describe the clinical features and treatment outcomes of Korean patients with idiopathic intracranial hypertension. METHODS: We prospectively recruited patients with idiopathic intracranial hypertension from one hospital and retrospectively analyzed the medical records of 11 hospitals in Korea. We collected data regarding preceding medical conditions or suspected medication exposure, headache phenotypes, other associated symptoms, detailed neuroimaging findings, treatments, and outcomes after 1-2 and 3-6 months of treatment. RESULTS: Fifty-nine (83.1% women) patients were included. The mean body mass index was 29.11 (standard deviation, 5.87) kg/m2; only 27 patients (45.8%) had a body mass index of ≥ 30 kg/m2. Fifty-one (86.4%) patients experienced headaches, patterns of which included chronic migraine (15/51 [29.4%]), episodic migraine (8/51 [15.7%]), probable migraine (4/51 [7.8%]), chronic tension-type headache (3/51 [5.9%]), episodic tension-type headache (2/51 [3.9%]), probable tension-type headache (2/51 [3.9%]), and unclassified (17/51 [33.3%]). Medication overuse headache was diagnosed in 4/51 (7.8%) patients. After 3-6 months of treatment, the intracranial pressure normalized in 8/32 (25.0%), improved in 17/32 (53.1%), no changed in 7/32 (21.9%), and worsened in none. Over the same period, headaches remitted or significantly improved by more than 50% in 24/39 patients (61.5%), improved less than 50% in 9/39 (23.1%), and persisted or worsened in 6/39 (15.4%) patients. CONCLUSION: Our findings suggest that the features of Asian patients with idiopathic intracranial hypertension may be atypical (i.e., less likely obese, less female predominance). A wide spectrum of headache phenotypes was observed. Medical treatment resulted in overall favorable short-term outcomes; however, the headaches did not improve in a small proportion of patients.

Neurofilament light chain is elevated in patients with newly diagnosed idiopathic intracranial hypertension: A prospective study.

BACKGROUND: Idiopathic intracranial hypertension is a secondary headache disorder potentially causing visual loss. Neurofilament light chain is a candidate, prognostic biomarker, but further studies of neuronal biomarkers are needed. Our objective was to investigate neurofilament light chain in cerebrospinal fluid (cNfL) and plasma (pNfL), amyloid-beta 42 (Aß-42), total-tau and phosphorylated-tau in cerebrospinal fluid in new-onset idiopathic intracranial hypertension. METHODS: Prospective case-control study including new-onset idiopathic intracranial hypertension and age, sex and BMI matched controls. Biomarkers were compared between patients and controls and related to papilledema, visual fields and opening pressure. RESULTS: We included 37 patients and 35 controls. Patients had higher age-adjusted cNfL (1.4 vs. 0.6 pg/mL, p-adjusted < 0.001), pNfL (0.5 vs. 0.3 pg/mL, p-adjusted < 0.001) and total-tau/Aß-42 (0.12 vs. 0.11, p-adjusted = 0.039). Significant, positive linear correlations were found between cNfL, pNfL, total-tau/Aß-42 and opening pressure. Patients with severe papilledema had elevated cNfL compared to mild-moderate papilledema (median cNfL: 4.3 pg/mL (3.7) versus 1.0 pg/mL (1.4), p-adjusted = 0.009). cNFL was inversely associated with perimetric mean deviation (r = -0.47, p-adjusted < 0.001). CONCLUSIONS: cNfL, pNfL and total-tau/Aß-42 were elevated in new-onset idiopathic intracranial hypertension. cNfL was associated with severity of papilledema and visual field defects at diagnosis. This indicates early axonal damage. Neurofilament light chain is a candidate biomarker for disease severity.

The additive value of complementing diagnostic idiopathic intracranial hypertension criteria by MRI - an external validation study.

BACKGROUND: Recently, diagnostic criteria including a standardized MRI criterion were presented to identify patients suffering from idiopathic intracranial hypertension (IIH) proposing that IIH might be defined by two out of three objective findings (papilledema, ≥ 25 cm cerebrospinal fluid opening pressure (CSF-OP) and ≥ 3/4 neuroimaging signs). METHODS: To provide independent external validation, we retrospectively applied the proposed diagnostic criteria to our cohort of patients with clinical suspicion of IIH from the Vienna IIH database. Neuroimaging was reevaluated for IIH signs according to standardized definitions by a blinded expert neuroradiologist. We determined isolated diagnostic accuracy of the neuroimaging criterion (≥ 3/4 signs) as well as overall accuracy of the new proposed criteria. RESULTS: We included patients with IIH (n = 102) and patients without IIH (no-IIH, n = 23). Baseline characteristics were balanced between IIH and no-IIH groups, but papilledema and CSF-OP were significantly higher in IIH. For the presence of ≥ 3/4 MRI signs, sensitivity was 39.2% and specificity was 91.3% with positive predictive value (PPV) of 95.2% and negative predictive value (NPV) 25.3%. Reclassifying our cohort according to the 2/3 IIH definition correctly identified 100% of patients without IIH, with definite IIH and suggested to have IIH without papilledema by Friedman criteria, respectively. CONCLUSION: The standardized neuroimaging criteria are easily applicable in clinical routine and provide moderate sensitivity and excellent specificity to identify patients with IIH. Defining IIH by 2/3 criteria significantly simplifies diagnosis without compromising accuracy.

Is increased activator protein 1 in cerebrospinal fluid as a potential biomarker that distinguishes idiopathic intracranial hypertension from multiple sclerosis?

OBJECTIVES: To distinguish whether idiopathic intracranial hypertension (IIH) is a condition predisposing to multiple sclerosis (MS) or an isolated disease, the current gene transcription factor Activator Protein-1 (AP-1) was evaluated with its potential to differentiate both diseases. BACKGROUND: The aim of this study was to investigate the use of AP-1 as biomarkers for the discrimination of IIH and MS. METHODS: AP-1, TNF-α, and IL-6 protein values in the CSF of the cases were evaluated by the ELISA method. The numerical measures of the groups and the ability of AP-1 to distinguish the groups were analyzed with the ROC curve. RESULTS: There was no difference between the groups in CSF TNF-α, IL-6, CSF, and serum biochemistry analyses. However, it was determined that the AP-1 concentration (pg/ml) was significantly higher in the IIH group, the sensitivity of AP-1 in separating those with IIH was 75%, and the specificity in separating those with MS was 60% in those with an AP-1 concentration of 606.5 and above. CONCLUSION: According to our results, the fact that CSF TNF-α and IL-6 values did not differ in IIH compared to MS revealed that IIH could not methodologically control MS, and AP-1 was a supportive parameter in differentiating both diseases (Tab. 2, Fig. 1, Ref. 31).

Foundations of the Diagnosis and Management of Idiopathic Intracranial Hypertension and Pulsatile Tinnitus.

Venous sinus stenosis has garnered increasing academic attention as a potential etiology of idiopathic intracranial hypertension (IIH) and pulsatile tinnitus (PT). The complex anatomy of the cerebral venous sinuses and veins plays a crucial role in the pathophysiology of these conditions. Venous sinus stenosis, often found in the superior sagittal or transverse sinus, can lead to elevated intracranial pressure (ICP) and characteristic IIH symptoms. Stenosis, variations in dural venous anatomy, and flow dominance patterns contribute to aberrant flow and subsequent PT. Accurate imaging plays a vital role in diagnosis, and magnetic resonance (MR) venography is particularly useful for detecting stenosis. Management strategies for IIH and PT focus on treating the underlying disease, weight management, medical interventions, and, in severe cases, surgical or endovascular procedures. Recently, venous sinus stenting has gained interest as a minimally invasive treatment option for IIH and PT. Stenting addresses venous sinus stenosis, breaking the feedback loop between elevated ICP and stenosis, thus reducing ICP and promoting cerebrospinal fluid outflow. The correction and resolution of flow aberrances can also mitigate or resolve PT symptoms. While venous sinus stenting remains an emerging field, initial results are promising. Further research is needed to refine patient selection criteria and evaluate the long-term efficacy of stenting as compared to traditional treatments.

Idiopathic intracranial hypertension as the initial presenting manifestation of systemic lupus erythematosus in a child.

Idiopathic intracranial hypertension (IIH) is a diagnosis of exclusion characterized by features of raised intracranial pressure (ICP) in the absence of brain parenchymal lesion, vascular malformations, hydrocephalus, or central nervous system (CNS) infection. Commonly used other terms for this entity include benign intracranial hypertension (BIH) or pseudotumor cerebri. Few case reports of systemic lupus erythematosus (SLE) presenting as IIH are available in the literature. We report a 12-year-old girl presented with chronic holocranial headache and occasional episodes of projectile vomiting for the last 6 months and then developed blurring of vision for the last month. She fulfilled the criteria for IIH. Subsequent evaluation revealed a diagnosis of SLE. The occurrence of IIH in SLE is not coincidental and is reported in 1%-5.4% of patients with SLE. Though corticosteroids have not been widely used in IIH, underlying SLE warranted administering corticosteroids with subsequent complete resolution of IIH. Pediatricians, neurologists, intensivists, and ophthalmologists should consider SLE as a differential diagnosis in children presenting with IIH.

Idiopathic intracranial hypertension associated with SARS-CoV-2 infection in an adult male patient: a case report and review of the literature.

BACKGROUND: Headache is a frequent symptom in coronavirus disease 2019 (COVID-19) patients, and idiopathic intracranial hypertension (pseudotumor cerebri) has been reported among patients who underwent lumbar puncture for persistent headaches. CASE PRESENTATION: A 45-year-old black man presented with dyspnea, cough, fever and headache for 05 days followed by blurring of vision associated with worsening of the headache. Physical examination was significant for tachypnea and oxygen desaturation and there were no abnormal neurologic findings. He tested positive for SARS-CoV-2 with nasopharyngeal swab PCR. His CSF opening pressure appeared high with normal CSF analysis and brain magnetic resonance imaging (MRI) revealed prominent subarachnoid space around the optic nerves and bilateral papilledema. He had significant improvement with medical therapy alone. CONCLUSION: Idiopathic intracranial hypertension (IIH) may occur in association with SARS-CoV-2 infection and should be considered when making a differential diagnosis for headache and blurring of vision. COVID-19 may play a role in the development of intracranial hypertension, even in the absence of known risk factors. Early diagnosis and treatment of IIH has paramount importance to prevent vision loss and other morbidities.

The Pseudotumor Cerebri Syndrome.

Pseudotumor cerebri syndrome is a syndrome of increased cerebrospinal fluid pressure without ventriculomegaly, mass lesion, or meningeal abnormality. It is either primary (idiopathic intracranial hypertension, IIH) or secondary. A secondary cause is unlikely when adhering to the diagnostic criteria. Permanent visual loss occurs if undetected or untreated, and the associated headaches may be debilitating. Fulminant disease may result in blindness despite aggressive treatment. This study addresses the diagnosis and management of IIH including new insights into the pathobiology of IIH, updates in therapeutics and causes of overdiagnosis.

Are the ICHD-3 criteria for headache attributed to idiopathic intracranial hypertension valid? Headache phenotyping and field-testing in newly diagnosed idiopathic intracranial hypertension.

BACKGROUND: Headache burden is substantial in idiopathic intracranial hypertension. The classification of idiopathic intracranial hypertension headache by the International Classification of Headache Disorders (ICHD) is an important tool for research and clinical purposes. METHODS: We phenotyped headaches and tested sensitivity and specificity of the ICHD-3 criteria for idiopathic intracranial hypertension headache in a prospective cohort of patients suspected of idiopathic intracranial hypertension at two tertiary headache centers. RESULTS: Sensitivity was 93% and specificity was 100% of ICHD-3 criteria for idiopathic intracranial hypertension-related headache validated in idiopathic intracranial hypertension (n = 140) and patients in whom idiopathic intracranial hypertension was suspected but disproven (n = 103). The phenotype of new/worsened headaches related to idiopathic intracranial hypertension suspicion was equally migraine-like (p = 0.76) and tension-type-like (p = 0.08). Lumbar puncture opening pressure was higher (p < 0.0001) and pulsatile tinnitus more frequent (p < 0.0001) in idiopathic intracranial hypertension patients, but neither improved the applicability of the headache criteria, nor did papilledema. CONCLUSION: Headache phenotype is not distinct in idiopathic intracranial hypertension. ICHD-3 criteria for idiopathic intracranial hypertension headache are sensitive and specific, but simplicity can be improved without compromising accuracy. We propose that a new or worsened headache temporally related to active idiopathic intracranial hypertension is a sufficient criterion for idiopathic intracranial hypertension headache regardless of headache phenotype or accompanying symptoms, and that elements of idiopathic intracranial hypertension diagnostics (papilledema and opening pressure) be segregated from headache criteria.Trial Registration: ClinicalTrials.gov Identifier: NCT04032379.

Rebound Intracranial Hypertension.

PURPOSE OF REVIEW: Rebound intracranial hypertension (RIH) is a post-procedural treatment complication in patients with spontaneous intracranial hypotension (SIH) characterized by transient high-pressure headache symptoms. This article reviews the epidemiology, clinical features, risk factors, and treatment options for RIH. RECENT FINDINGS: This article discusses how changes in underlying venous pressure and craniospinal elastance can explain symptoms of RIH, idiopathic intracranial hypertension (IIH), and SIH. The pathophysiology of RIH provides a clue for how high and low intracranial pressure disorders, such as IIH and SIH, are connected on a shared spectrum.

Assessment of the relationship between structural and functional tests in patients with idiopathic intracranial hypertension.

PURPOSE: To assess the relationship between structural and functional tests in mild and moderate idiopathic intracranial hypertension (IIH). METHODS: Patients with mild and moderate IIH and a control group were enrolled. Best-corrected visual acuity (BCVA), macular ganglion cell layer (MGCL) thickness, peripapillary retinal nerve fiber layer (pp RNFL) thickness, perimetric mean deviation (MD), and photopic negative responses (PhNR) of the electroretinogram were recorded. The associations between structural (pp RNFL and MGCL thickness) and functional (PhNR amplitude, MD and BCVA) parameters were assessed. RESULTS: 154 eyes from 78 subjects (74 eyes from IIH patients and 80 eyes from healthy subjects) were included in this comparative observational study. The MGCL thickness, VA, pp RNFL, and PhNR base-to-trough (BT) amplitude were significantly worse in moderate IIH. The BCVA and MD were associated with MGCL thickness only in moderate IIH. The relationship between MD and MGCL thickness started when MD fell below -5.7 dB. CONCLUSIONS: The association between functional and structural parameters varies between mild and moderate IIH. The MD and MGCL thickness outperformed in assessing disease severity in mild and moderate IIH, respectively. The association between MD and MGCL thickness could be considered in IIH severity categorization.

The impact of eating disorders on idiopathic intracranial hypertension.

BACKGROUND: Idiopathic intracranial hypertension (IIH) occurs more frequently in obese females of childbearing age. A link between eating disorders and poor outcome has been suggested but remains unproven. METHODS: This prospective field study at two tertiary headache centers included patients with clinically suspected IIH after standardized diagnostic work-up. Eating disorders were evaluated using validated questionnaires (EDQs). Primary outcome was the impact of eating disorders on IIH severity and outcome, secondary outcome was the prevalence and type of eating disorders in IIH compared to controls. RESULTS: We screened 326 patients; 143 patients replied to the EDQs and were classified as 'IIH' or 'non-IIH' patients. The demographic profile of EDQ-respondents and non-respondents was similar. Presence of an eating disorder did not impact IIH severity (lumbar puncture opening pressure (p = 0.63), perimetric mean deviation (p = 0.18), papilledema (Frisén grad 1-3; p = 0.53)) nor IIH outcome (optic nerve atrophy (p = 0.6), impaired visual fields (p = 0.18)). Moreover, we found no differences in the prevalence and type of eating disorders when comparing IIH with non-IIH patients (p = 0.09). CONCLUSION: Eating disorders did not affect IIH severity or outcome. We found the same prevalence and distribution pattern of eating disorders in IIH and non-IIH patients advocating against a direct link between IIH and eating disorders.

Persistent Elevation of Opening Pressure Despite Treatment and Symptom Resolution in Pediatric Intracranial Hypertension.

BACKGROUND: Currently no guidelines for repeating a lumbar puncture to guide management in primary intracranial hypertension (PIH) exist. METHODS: An institutional database of patients 18 years and younger followed in the institution's pediatric intracranial hypertension clinic was examined for opening pressure changes in PIH at diagnosis, before medication wean, and following medication wean, as well as to examine whether measurements at the time of diagnosis differed between those with and without disease recurrence. RESULTS: Forty-two patients were included in this study; 36% were male and the mean age at diagnosis was 11.01 years. Treatment duration averaged 9.68 months in those without recurrence and 8.5 months in those with recurrence. Average body mass index percentile of patients with disease recurrence was 83.7 and 72.1 in those without recurrence (P = 0.16). Average opening pressure values of all patients at diagnosis, prewean, and postwean was 36.53 cm H2O, 30.7 cm H2O, and 31.1 cm H2O, respectively. There was no statistically significant difference in opening pressures across these time points (P = 0.14). The change in opening pressure from diagnosis to postwean was statistically significant with a reduction of 5.18 cm H2O (P = 0.04). There was no statistical difference between change in opening pressure at diagnosis versus postwean between those with and without recurrence (P = 0.17). CONCLUSIONS: This clinical observational study suggests that mean opening pressure measurements in patients with PIH remain elevated both before and after medication wean despite papilledema resolution and patient-reported PIH symptoms. Clinically, this suggests that other features such as signs of optic disc edema and symptoms should be used to inform a clinical determination of disease recurrence and treatment course.

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.

Undiagnosed sagittal synostosis as cause of "idiopathic" intracranial hypertension.

PURPOSE: Idiopathic intracranial hypertension (IIH) is a rare condition in children, but if diagnosed needs to be promptly treated to avoid clinical sequalae. The main purpose of this paper was to test our clinical experience with a cohort of normocephalic children with craniosynostosis who do not present in the routine way to craniofacial services, due to the normal head shape and age, diagnosed with IIH. METHODS: We retrospectively reviewed all children who were referred to neurosurgery from 2012 to 2022 for management of IIH on our prospectively kept database. We determined what treatments were offered and if there was an associated craniosynostosis. RESULTS: In total, 19 children were identified with an average age at referral of 11.5 years (st dev 4.0 years) with 11 male and 8 female. The most common presenting symptoms and signs were papilloedema (18/19), headaches (15/19), visual deterioration (9/19), nausea and vomiting (7/19) and diplopia (4/19). Five out of 19 children (26.3%) had a sagittal suture fused that was not identified at the time of treatment and all children were normocephalic. CONCLUSION: There is a cohort of children with IIH who will have concomitant craniosynostosis and ideally would benefit from cranial vault expansion as primary surgery rather than cerebrospinal fluid (CSF) diversion. We suggest all children with IIH requiring neurosurgical intervention have cross-sectional imaging to look for occult craniosynostosis prior to intervention.

Spontaneous rhinorrhea and idiopathic intracranial hypertension: a complex and challenging association.

INTRODUCTION: Spontaneous CSF leak is a known complication of idiopathic intracranial hypertension (IIH). Patients with CSF rhinorrhea present a unique challenge within the IIH population, as the occurrence of a leak can mask the typical IIH symptoms and signs, complicating the diagnosis. Treatment of leaks in this population can also be challenging, with the risk of rhinorrhea recurrence if intracranial hypertension is not adequately treated. OBJECTIVE: The aim of this narrative review was to examine current literature on the association between spontaneous CSF rhinorrhea leaks and IIH, focusing on key clinical features, diagnostic approaches, management strategies, and outcomes. MATERIAL AND METHODS: A literature search was executed using the PubMed and Scopus databases. The search was confined to articles published between January 1985 and August 2023; extracted data was then analysed to form the foundation of the narrative review. RESULTS: This search yielded 26 articles, comprising 943 patients. Average age was 46.8 ± 6.5 years, and average body mass index was 35.8 ± 4.8. Most of the patients were female (74.33%). Presenting symptoms were rhinorrhea, headaches and meningitis. The most common imaging findings were empty sella and encephalocele. The standard treatment approach was endoscopic endonasal approach for correction of CSF rhinorrhea leak, and shunt placement was also performed in 128 (13%) patients. Recurrences were observed in 10% of cases. CONCLUSIONS: The complex relationship between spontaneous CSF leaks and IIH is a challenge that benefits from multidisciplinary evaluation and management for successful treatment. Treatments such as endoscopic repair, acetazolamide, and VP/ /LP shunts reduce complications and recurrence. Personalised plans addressing elevated intracranial pressure are crucial for successful outcomes.

Myelin oligodendrocyte glycoprotein (MOG) associated optic neuritis in a patient with idiopathic intracranial hypertension (IIH) and compressive optic neuropathy case report.

BACKGROUND: Myelin oligodendrocyte glycoprotein-associated disease (MOGAD) has a wide phenotypic expression and should be considered in a differential diagnosis of patients with optic disc edema and increased intracranial pressure because MOGAD can mimic IIH and compressive optic neuropathy. CASE PRESENTATION: A 53-year-old woman with a history of presumed idiopathic intracranial hypertension ("IIH") presented with new headache and visual loss. She had a BMI of 35.44 kg/m2 and a past medical history significant for depression, hepatitis C, hyperlipidemia, and uterine cancer post-hysterectomy. She had undergone multiple lumboperitoneal shunts for presumed IIH and had a prior pituitary adenoma resection. Her visual acuity was no light perception OD and counting fingers OS. After neuro-ophthalmic consultation, a repeat cranial MRI showed symmetric thin peripheral optic nerve sheath enhancement of the intra-orbital optic nerves OU. Serum MOG antibody was positive at 1:100 and she was treated with intravenous steroids followed by plasma exchange and rituximab. CONCLUSIONS: This case highlights the importance of considering MOGAD in the differential diagnosis of optic neuropathy. Although likely multifactorial, we believe that the lack of improvement in our case from presumed IIH and despite adequate neurosurgical decompression of a pituitary adenoma with compression of the optic apparatus reflected underlying unrecognized MOGAD. Clinicians should consider repeat imaging of the orbit (in addition to the head) in cases of atypical IIH or compressive optic neuropathy especially when the clinical course or response to therapy is poor or progressive.