Outcomes measures in idiopathic intracranial hypertension

ABSTRACT

Introduction: Idiopathic intracranial hypertension is a condition characterized by raised intracranial pressure, papilledema, and normal neuroimaging (aside from radiological signs of raised intracranial pressure). Symptoms of idiopathic intracranial hypertension include chronic headaches and for some, visual loss. New treatments are unmet clinical needs.

Areas covered: The aim of this review is to present the evidence base and considered opinion on outcome measures to determine successful management of idiopathic intracranial hypertension.

Expert opinion: Less invasive measures of disease activity such as optical coherence tomography will continue to grow in this field, both as a measure of papilledema, and potentially as a surrogate for intracranial pressure and visual function. As a highly disabling aspect of the disease is headache, treatment outcomes for headache morbidity need to be appropriately chosen and standardized to allow comparison between trials.

KEYWORDS:

• Idiopathic intracranial hypertension
• intracranial pressure
• headache
• obesity
• optical coherence tomography
• papilledema
• pseudotumour cerebri
• randomized control trial
• vision and weight loss

Article highlights

• Headache is the predominant symptom of IIH, is typically migraine like, and is prioritized highly by patients and physicians.

• Headache influences the quality of life in IIH rather than the measures of vision.

• Headache therapy is an unmet clinical need in this patient population, and trials investigating headache therapy are desperately needed.

• Optical coherence tomography provides an accurate objective assessment of changes in optic nerve head height in papilloedema, as compared to more categorical groups used in clinical assessment of papilledema.

• Measurement of the optic nerve head with optical coherence tomography imaging have been shown to have the potential to be used to predict changes in intracranial pressure.

• The measurement of the optic nerve head with optical coherence tomography imaging have been shown to be used to predict changes in the visual field.

• Until a disease-specific quality of life tool for IIH is developed and validated, it is likely investigators will continue to use multiple tools to measure changes in the quality of life following interventions. Change in the quality of life measurements may also be useful in clinical practice to allow for a holistic approach to managing IIH.

• Outcome selection for emergency surgical treatment to mitigate visual loss is challenging but vital to assess in the setting of randomized controlled trials.

Declaration of interest

SP Mollan declares work on an Invex therapeutics advisory board (2019); Invex therapeutics consultancy work (2020, 2021) and receiving speaker fees from Heidelberg engineering (2019, 2020, 2021). They have also received Honoria from Novartis for speaking on fundoscopsy, but within a National headache network meeting (November 2019). AJ Sinclair has received speaker fees and Honoraria from Novartis (erenumab) and Allergan (BOTOX), in addition to working as a company director with salary and stock options for Invex therapeutics (2019, 2020, 2021). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or conflict with the subject matter or materials discussed in this manuscript apart from those disclosed.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

AJ Sinclair is supported by a Sir Jules Thorn Award for Biomedical Research.