Endocrinology of Pseudotumor Cerebri

Diagnosis of idiopathic intracranial hypertension - the importance of excluding secondary causes: A systematic review

BACKGROUND

Idiopathic intracranial hypertension is characterized by increased intracranial pressure without any pathological findings on neuroimaging, except for signs of high intracranial pressure. Before diagnosing idiopathic intracranial hypertension secondary causes of increased intracranial pressure should be excluded.

OBJECTIVE

to characterize the phenotype of patients with secondary intracranial hypertension and to identify possible risk factors for secondary intracranial hypertension.

METHODS

We have systematically searched the PubMed database. The publications were analyzed according to the patient phenotype, age, gender, comorbidities, body mass index/weight status, and additional medication. The results are summarized in four categories: medication, infection, hormonal induced intracranial hypertension and miscellaneous groups of diseases related to sIH.

RESULTS

We identified 105 eligible papers which included 272 cases. There were 49.6% pediatric cases. Among the adult group,70.9% were women. A total of 40.4% of all cases were obese or overweight, 27% among adults and 13.4% among pediatric cases. Increased BMI and recent weight gain, anemia, renal diseases and hypertension were the most frequent comorbidities related to sIH.

CONCLUSION

Among sIH patients, 40.4% were obese or overweight; two thirds were women. We recommend that even patients with a typical IIH phenotype should be screened for secondary causes.

Elevated Intracranial Pressure Associated With Exogenous Hormonal Therapy Used for Gender Affirmation

BACKGROUND

Addison disease, corticosteroid withdrawal, and taking synthetic growth hormone have been linked with development of intracranial hypertension, but there is still debate on whether administration of other exogenous hormones plays a role in precipitating elevated pressure. The growing use of hormonal therapy for gender affirmation provides an opportunity to explore this possibility.

METHODS

All transgender patients taking exogenous hormones for female-to-male (FTM) and male-to-female (MTF) transitions who were diagnosed with intracranial hypertension at Massachusetts Eye and Ear Infirmary, Massachusetts General Hospital and Beth Israel Deaconess Medical Center between August 2014 and November 2018 were included in a retrospective review. Visual acuity, type, and dose of exogenous hormone, visual field testing, clinical exam, results of neuroimaging and lumbar puncture, and treatment modalities were catalogued and analyzed.

RESULTS

Six transgender individuals were identified. Five were FTM, with an average hormone treatment time of 18.4 months, and one was MTF who had been treated with hormones for 4 years. The average age of all patients was 23.5 years. The average time between onset of symptoms and presentation was 5 months. Fifty percent of the patients reported pulse-synchronous tinnitus, 83% reported positional headache, 33% reported transient visual obscurations, and 16% reported diplopia. Lumbar punctures performed on 4 of the patients revealed elevated opening pressures and normal cerebrospinal fluid constituents. MRI findings consistent with elevated intracranial pressure (ICP) were present in the other 2 patients in whom lumbar puncture was unsuccessful. Four patients were treated with acetazolamide and one was treated with topiramate, with an average follow-up time of 15.7 months. All patients demonstrated bilateral optic disc swelling, and all maintained normal acuity and color vision. Performance on visual field testing was not significantly affected in any patient.

CONCLUSIONS

This is the largest reported series to date of gender-transitioning patients with intracranial hypertension, including one novel MTF conversion. These observations warrant further investigation into the possible link of exogenous hormonal therapy and elevated ICP and any mechanisms or confounders underlying this potential association.

The prevalence of polycystic ovary syndrome in women with idiopathic intracranial hypertension

Purpose. The purpose of this study is to re-evaluate whether the prevalence of polycystic ovary syndrome (PCOS) amongst women with idiopathic intracranial hypertension (IIH) is higher than in the general population using the NIH criteria. Methods. We included all consecutive women with IIH of child-bearing age seen at a hospital-based neuro-ophthalmology clinic between the years 2000-2005. All consenting women included in this study filled-out a screening questionnaire aimed at identifying women at risk for PCOS. The endocrinologist examined each patient suspect of PCOS as well as their biochemical results and diagnosed PCOS according to NIH criteria. The prevalence of PCOS in these women with IIH was compared with the reported prevalence of PCOS in the general population. Results. Out of 58 women with IIH who completed the study, definite PCOS was diagnosed in nine women (9/58; 15.5%). We found a significantly higher prevalence of PCOS using the NIH criteria among the IHH study group (15.5%, P = 0.001) compared to the general population (8.7%). Conclusions. The prevalence of PCOS is higher among patients with IHH, compared to the general population. We suggest a novel screening questionnaire to aid in the identification of women with IIH at risk for PCOS.

More than meets the eye? Redefining idiopathic intracranial hypertension

Idiopathic intracranial hypertension (IIH) is a disease of unknown etiology associated with increased intracranial pressure, predominantly affecting obese females of childbearing age. The history of IIH is quite unique, featuring only limited advancements in evidenced-based treatments, but boasting literally countless changes in nomenclature, proposed etiology, and conceptual approach. Despite its elusive pathogenesis, an evolution of our approach to IIH can be traced sequentially through identifiable periods. Contemporary research suggests that we are approaching a new phase in IIH, redefining it as a global neurologic syndrome with more far-reaching effects than previously realized.

The Relation of Brain Ouabain-Like Compounds and Idiopathic Intracranial Hypertension

OBJECTIVES

To determine the relationship between levels of ouabain-like compounds (OLC) in the cerebrospinal fluid (CSF) and the occurence of idiopathic intracranial hypertension (IIH).

BACKGROUND

OLC are naturally occurring inhibitors of the sodium-potassium ATPase that are found in the CSF of mammals. Since the production of CSF is dependent upon sodium-potassium ATPase activity, and since there is evidence that the increased intracranial pressure found in the condition of IIH may be the result of increased CSF production, we hypothesized that the level of endogenous OLC would be reduced in the CSF of patients with IIH.

METHODS

CSF samples were obtained from n = 7 patients with IIH and n = 31 patients with neurological disorders other than IIH ("control" patients) who had lumbar puncture as part of their routine evaluation or treatment. The concentration of OLC in the CSF samples was measured using an established ELISA.

RESULTS

Patients with IIH exhibited a concentration of OLC in the CSF of 0.11 +/- 0.03 ng/mL. In comparison, the concentration of OLC in CSF samples from non-IIH control patients was 0.12 +/- 0.01 ng/mL. These values were not statistically different when compared with a t-test (P= 0.31). However, the concentration of OLC did negatively correlate to the opening pressure on lumbar puncture, but only in the IIH group (r=-0.80, P= .03). Furthermore, IIH patients who were newly diagnosed or who were unsuccessfully treated (n = 5 of 7 IIH patients) exhibited OLC concentrations of 0.06 +/- 0.1 ng/mL, which is nearly lower than that of the control group (P= .06).

CONCLUSIONS

The average concentration of OLC in IIH patients (treated and untreated) is unlikely to be distinguishable from that in non-IIH control patients with other neurological conditions. However, the concentration of OLC may be inversely related to the intracranial pressure in patients with IIH, and it may prove to be lower in the subgroup of untreated and unsuccessfully treated IIH patients.

Emergency department presentation of idiopathic intracranial hypertension

Idiopathic intracranial hypertension (IIH), or pseudotumor cerebri, is a syndrome characterized by an elevated intracranial pressure in the absence of a focal lesion, infective process, or hydrocephalus. New onset IIH may present to the emergency department in a variety of ways. To describe the etiologic associations and clinical features in this disorder, we performed a retrospective analysis of consecutive emergency department patients with new onset IIH during the calendar years 1987-1996. A total of 52 patients met all study criteria. The mean patient age was 27+/-8.9 years; the female-to-male ratio was 7:1. An etiologic association could be identified in 85% of cases and included obesity, hypertension, drugs, endocrine, and systemic disorders. Headache was a dominant complaint in most patients (48/52) and associated with dizziness, nausea, and/or visual complaints. Fourteen patients (27%) were not diagnosed on their initial ED visit and were more likely to have atypical clinical features (71% vs. 24%; P = .004). Atypical features included paraesthesias, neck/back pain, unilateral headache, vertigo, and nystagmus. Papilledema, the ophthalmoscopic hallmark of IIH, was not detected initially in 11 patients (21%). These results suggest that IIH is a relatively uncommon neurological illness that may have a variety of causes. The emergency department diagnosis may be complicated by atypical clinical features and a lack of detectable papilledema.

Idiopathic intracranial hypertension: orbital MRI

The case is reported of a patient with idiopathic intracranial hypertension examined with magnetic resonance imaging. Marked enhancement of the optic nerve heads was found, which might be related to blood-retinal barrier breakdown related to a sudden rise in intracranial cerebrospinal fluid pressure.

Idiopathic intracranial hypertension (pseudotumor cerebri) in pediatric patients

Improved evaluation of visual features of idiopathic intracranial hypertension in pediatric patients has resulted in the demonstration of optic neuropathy which may be reversible. A wide variety of etiologic associations should be investigated to provide definitive therapy; however, nonspecific means often will be required to lower intracranial pressure. It is hoped that a double-blind controlled trial of medical therapies and another for surgical therapies will be conducted to elucidate optimum management of this condition.