Clinical Features and Diagnosis of Spontaneous Intracranial Hypotension

This article reviews the current understanding of the varied clinical presentations of spontaneous intracranial hypotension and discusses strategies and limitations in diagnosing this complex syndrome, including approaches for medical practitioners outside of specialty centers.

Radiologic algorithms applied to brain MRI (eg, the Bern score) can help assess the probability of an underlying spinal CSF leak, but they do not replace good history-taking and clinical acumen. Brain MRI findings may evolve over time with or without leak-directed treatment. New techniques and improvements in imaging technology have led to better identification and classification of different types of spinal CSF leaks, especially CSF-venous fistulas that were reported for the first time in 2014 and now account for 50% or more of the leaks in patients without spinal extradural fluid collections. Occasionally, spontaneous intracranial hypotension is the result of preexisting intracranial hypertension causing "blowout" leaks.

Spontaneous intracranial hypotension is caused by leakage of CSF from the spinal dura and most often presents with orthostatic headache, frequently accompanied by neck pain and stiffness, nausea, vestibulo-auditory distortions, visual changes, and other symptoms. Spontaneous intracranial hypotension can be debilitating, and long diagnostic and treatment delays are common. In rare cases, spontaneous intracranial hypotension can have dangerous sequelae, including superficial siderosis, subdural hematoma, bibrachial amyotrophy, brain sagging dementia, and even death. Early recognition of clinical symptoms and radiologic signs is imperative for best patient outcomes.