UNASSIGNED: To characterise the ophthalmic indications for, and ophthalmic efficacy of, transverse sinus stenting in adults with medically refractory idiopathic intracranial hypertension.
UNASSIGNED: A retrospective cohort study was undertaken on a single-author database of 226 successive patients with confirmed idiopathic intracranial hypertension (IIH). A total of 32 patients were identified who received a transverse sinus stent for medically refractory disease. This which was defined as visual threat and/or intolerance of maximal medical therapy. Patients with medically refractory disease proceeded to stenting, if found to have a significant transverse sinus stenosis gradient at catheter venography. Visual threat was quantified via the degree of papilledema on optical coherence tomography of the retinal nerve fibre layer, and via the visual field mean deviation. CSF opening pressure at lumbar puncture and cerebral venous sinus pressure measurements from catheter venography were correlated with the ophthalmic data, noting also intolerance of maximal medical therapy. Complications of stenting were fully assessed.
UNASSIGNED: Medically refractory IIH was found in 18% of the total cohort of IIH patients. 90% of those with medically refractory disease had a significant transverse sinus stenosis pressure gradient, and 80% proceeded to stenting. The intervention eliminated papilledema in 96% of stented patients, and allowed 81% to cease acetazolamide. The need for a further procedure was low at 6%, and the safety profile was favourable.
UNASSIGNED: Medically refractory disease in IIH is common (18%), and nearly always associated with a significant transverse sinus stenosis pressure gradient (90%). Endovascular stenting of the stenosis deserves wider uptake as a highly effective, safe, and usually definitive treatment. It safeguards vision by eliminating papilledema (96%), and allows most patients to cease acetazolamide (81%). By analogy with glaucoma, if acetazolamide is the prostaglandin of IIH and CSF diversion the emergency glaucoma filter, stenting is the minimally invasive glaucoma surgery.

Fulminant idiopathic intracranial hypertension (IIH) is a rapid vision-degrading presentation of IIH with limited published studies. This study composed a narrative review of fulminant IIH with the aim of better characterising fulminant IIH presentation and visual outcomes. SCOPUS and PubMed were searched for papers referencing IIH, benign intracranial hypertension, or pseudotumour cerebri. Abstracts were screened for rapid degradation in vision. All studies were required to meet both the modified Dandy and fulminant IIH criteria. Thirty-six studies met the inclusion criteria. Demographics, treatments, and visual outcome data were collected. Case studies made up 69% of the studies and 31% were case series. In total, 72 patients with fulminant IIH were reported, of which 23.6% were paediatric and 96% were female. Surgical intervention occurred in 85% of patients. Anaemia was present in 11% of patients and 85.7% of paediatric patients had a sixth cranial nerve palsy. In conclusion, we propose the following practice guidelines to assist in diagnosing and treating fulminant IIH patients: 1) patients who present with optic disc oedema require urgent visual field testing to evaluate for vision loss; 2) a paediatric patient presenting with a sixth cranial nerve palsy should have a comprehensive eye examination; 3) fulminant IIH can occur in patients with a normal body mass index; and 4) anaemia should be tested for in the setting of fulminant IIH. As little is known about the optimal treatment mechanisms for this presentation, multi-institutional and international collaborations will be a critical step for future research.

OBJECTIVE: To evaluate the effect of weight reduction on the structural and functional parameters of the optic nerve in established cases of papilledema in Idiopathic Intracranial Hypertension (IIH).
METHODS: A prospective observational study in early and established cases of papilledema in IIH presenting from December 2019 to February 2021. Functional parameters (visual acuity, contrast sensitivity, mean deviation, VER), structural parameters (RNFL, GCL-IPL, and optic disc height), and clinical grading of papilledema were measured at baseline and every 6 weeks for 6 months. All patients underwent medical (oral acetazolamide) and diet therapy.
RESULTS: Mean body mass index (BMI) at presentation was 26.32 ± 3.52 kg/m² and the mean change in BMI over 6 months was 1.27 ± 0.50 kg/m². 67% of eyes had papilledema of grades 2-3 at the presentation. At the end of 6 months, 75% of eyes had grade 1 papilledema while 13% showed complete resolution. A reduction of 5.32 ± 3.58 in mean deviation (r = 0.316; p-value 0.01) and gain in VER P100 amplitude of 4.2 ± 2.7 µV (r = 0.40; p-value 0.003) were noted over 6 months with reduction in BMI over 6 months. A statistically significant reduction in optic disc height (ODH) was noticed with BMI reduction over 6 months (p = 0.0007; r = 0.45).A reduction of 1.72 ± 0.90 kg/m² (equivalent to 6.53% weight loss) in BMI was associated with a four-grade change in clinical grading of papilledema.
CONCLUSIONS: Reduction in BMI had a significant impact on both structural and functional parameters of the optic nerve in IIH. The involvement of a well-certified dietician should be an integral part of treatment in IIH.

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a syndrome exhibiting elevated intracranial pressure (ICP), visual disturbances, and severe headache. IIH primarily affects young obese women, though it can occur in individuals of any age, BMI, and sex. IIH is characterized by systemic metabolic dysregulation with a profile of increased androgen hormones. However, the contribution of obesity/hormonal perturbations to cerebrospinal fluid (CSF) dynamics remains unresolved.
METHODS: We employed obese female Zucker rats and adjuvant testosterone to reveal IIH causal drivers. ICP and CSF dynamics were determined with in vivo experimentation and magnetic resonance imaging, testosterone levels assessed with mass spectrometry, and choroid plexus function revealed with transcriptomics.
RESULTS: Obese rats had undisturbed CSF testosterone levels and no changes in ICP or CSF dynamics. Adjuvant testosterone treatment of obese rats elevated the CSF secretion rate, although with no effect on the ICP, due to elevated CSF drainage capacity of these rats.
CONCLUSIONS: Obesity in itself therefore does not suffice to recapitulate the IIH symptoms in rats, but modulation of CSF dynamics appears with adjuvant testosterone treatment, which mimics the androgen excess observed in female IIH patients. Obesity-induced androgen dysregulation may thus contribute to the disease mechanism of IIH and could potentially serve as a future therapeutic target.

BACKGROUND: The association of obstructive sleep apnea (OSA) with idiopathic intracranial hypertension (IIH) remains unclear, and few studies have used objective in-laboratory polysomnography (PSG) data. Thus, we used PSG data to examine the: 1) association between OSA, and its severity, with IIH and 2) sex differences in OSA severity in those with and without IIH.
METHODS: We retrospectively analyzed diagnostic PSG data from January 2015 to August 2023 for patients who were diagnosed with IIH by a neuro-ophthalmologist using the modified Dandy criteria. We selected three age, sex, and body mass index (BMI) matched controls for each IIH patient. We examined potential associations of IIH with OSA using regression. Sex differences were analyzed using ANOVA.
RESULTS: Of 3482 patients who underwent PSG, we analyzed 78 IIH patients (16 males) and 234 matched controls (48 males). Five (6.4 %) IIH and 39 (16.7 %) control patients had OSA, defined as AHI≥15. After adjusting for age, sex, BMI, and comorbidities, IIH was negatively associated with the presence of OSA (OR 0.29, 95%CI 0.10-0.87, p = 0.03). However, models that adjusted for acetazolamide use, with or without comorbidities, showed no significant relationship with OSA (OR 0.31, p = 0.20). Males with IIH had a significantly higher age (p = 0.020), OSA severity (p = 0.032), and arousal index (p = 0.046) compared to females with IIH.
CONCLUSIONS: IIH treated with acetazolamide was not an independent risk factor for OSA presence or severity. The presence of IIH treated with acetazolamide likely does not warrant routine screening for OSA, but related risk factors may identify appropriate patients.

Pulsatile spinal cord and CSF velocities related to the cardiac cycle can be depicted by phase-contrast MRI. Among patients with spontaneous intracranial hypotension, we have recently described relevant differences compared with healthy controls in segment C2/C3. The method might be a promising tool to solve clinical and diagnostic ambiguities. Therefore, it is important to understand the physiological range and the effects of clinical and anatomical parameters in healthy volunteers. Within a prospective study, 3D T2-weighted MRI for spinal canal anatomy and cardiac-gated phase-contrast MRI adapted to CSF flow and spinal cord motion for time-resolved velocity data and derivatives were performed in 70 participants (age 20-79 years) in segments C2/C3 and C5/C6. Correlations were analyzed by multiple linear regression models; p < 0.01 was required to assume a significant impact of clinical or anatomical data quantified by the regression coefficient B. Data showed that in C2/C3, the CSF and spinal cord craniocaudal velocity ranges were 4.5 ± 0.9 and 0.55 ± 0.15 cm/s; the total displacements were 1.1 ± 0.3 and 0.07 ± 0.02 cm, respectively. The craniocaudal range of the CSF flow rate was 8.6 ± 2.4 mL/s; the CSF stroke volume was 2.1 ± 0.7 mL. In C5/C5, physiological narrowing of the spinal canal caused higher CSF velocity ranges and lower stroke volume (C5/C6 B = +1.64 cm/s, p < 0.001; B = -0.4 mL, p = 0.002, respectively). Aging correlated to lower spinal cord motion (e.g., B = -0.01 cm per 10 years of aging, p < 0.001). Increased diastolic blood pressure was associated with lower spinal cord motion and CSF flow parameters (e.g., C2/C3 CSF stroke volume B = -0.3 mL per 10 mmHg, p < 0.001). Males showed higher CSF flow and spinal cord motion (e.g., CSF stroke volume B = +0.5 mL, p < 0.001; total displacement spinal cord B = +0.016 cm, p = 0.002). We therefore propose to stratify data for age and sex and to adjust for diastolic blood pressure and segmental narrowing in future clinical studies.

Mildly elevated intracranial pressure appears to be a distinct pathology separate from idiopathic increased intracranial pressure and migraine. Many patients present with head fullness-pressure and dizziness, which is often suggestive of a clinical diagnosis of vestibular migraine. These patients may additionally have episodic vertigo as seen in endolymphatic hydrops and positional vertigo in addition to feeling dizzy. In most cases, hearing is normal. A long duration of the condition or a presence of associated ear pathologies, i.e., dehiscence, fistula, hypermobile footplate, or history of chronic ear infections can add hearing loss to clinical presentations. Low-pitch pulsatile tinnitus, when present, is an important symptom. The neuroimaging findings such as partially empty sella, blockage of the dural venous sinus or sigmoid sinus wall defects are frequently observed. The condition is diagnosed by measuring the lumbar puncture opening pressure. Typically, patients have normal cerebrospinal fluid chemistry and microscopy. Lowering the pressure during the lumbar puncture will resolve the patient\'s symptoms temporarily. Medical therapy is typically successful using carbonic anhydrase inhibitors and corrections of medical disorders that may be contributing to the increased pressure. A few require shunting or stenting procedures. In this review article, we define the condition in detail with illustrative cases that we collected from our practices.

Spaceflight associated neuro-ocular syndrome (SANS) is a collection of distinct findings seen in some astronauts following prolonged spaceflight and is characterized by: optic disc edema, globe flattening, and choroidal folds. In this manuscript, we describe the potential mechanisms linking anemia and SANS. Future research aimed at understanding the relationship between these conditions may help to develop countermeasures and mitigation efforts for SANS.

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a condition characterized by increased intracranial pressure (ICP), impaired vision, and headache. Most cases of IIH occur in obese women of childbearing age, though age, BMI, and female sex do not encompass all aspects of IIH pathophysiology. Systemic metabolic dysregulation has been identified in IIH with a profile of androgen excess. However, the mechanistic coupling between obesity/hormonal perturbations and cerebrospinal fluid dynamics remains unresolved.
METHODS: Female Wistar rats were either fed a high fat diet (HFD) for 21 weeks or exposed to adjuvant testosterone treatment for 28 days to recapitulate IIH causal drivers. Cerebrospinal fluid (CSF) and blood testosterone levels were determined with mass spectrometry, ICP and CSF dynamics with in vivo experimentation, and the choroid plexus function revealed with transcriptomics and ex vivo isotope-based flux assays.
RESULTS: HFD-fed rats presented with increased ICP (65%), which was accompanied by increased CSF outflow resistance (50%) without altered CSF secretion rate or choroid plexus gene expression. Chronic adjuvant testosterone treatment of lean rats caused elevated ICP (55%) and CSF secretion rate (85%), in association with increased activity of the choroid plexus Na+,K+,2Cl- cotransporter, NKCC1.
CONCLUSIONS: HFD-induced ICP elevation in experimental rats occurred with decreased CSF drainage capacity. Adjuvant testosterone, mimicking the androgen excess observed in female IIH patients, elevated the CSF secretion rate and thus ICP. Obesity-induced androgen dysregulation may thus contribute to the disease mechanism of IIH.

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.