1. A D E W I J A Y A , M D – M A Y 2 0 2 3
Spontaneous Intracranial Hypotension
2. Introduction
A debilitating medical condition caused by loss of
CSF from the spinal canal
Not life threatening but cause considerable
morbidity, result in significant long-term disability,
and in rare cases leads to decreased level of
consciousness and coma
Takai K, Niimura M, Hongo H, et al. Disturbed Consciousness and Coma: Diagnosis and Management of Intracranial Hypotension Caused by a Spinal Cerebrospinal Fluid Leak. World
Neurosurg 2019; 121: e700–11.
Kranz PG, Gray L, Malinzak MD, Amrhein TJ. Spontaneous Intracranial Hypotension: Pathogenesis, Diagnosis, and Treatment. Neuroimaging Clin N Am 2019; 29: 581–94.
Paris D, Rousset D, Bonneville F, et al. Cerebral Venous Thrombosis and Subdural Collection in a Comatose Patient: Do Not Forget Intracranial Hypotension. A Case Report. Headache 2020;
60: 2583–8.
3. Epidemiology
Incidence: 5 cases per 100 000 person-years
Female : Male = 2 : 1
The peak incidence is around 40 years of age, and
SIH is rare but not absent in children
Risk factors: connective tissue disorder such as
Marfan syndrome and Ehlers-Danlos syndromes
Luetzen N, Dovi-Akue P, Fung C, Beck J, Urbach H. Spontaneous intracranial hypotension: diagnostic and therapeutic workup. Neuroradiology. 2021 Nov;63(11):1765-72.
Dobrocky T, Nicholson P, Häni L, Mordasini P, Krings T, Brinjikji W, Cutsforth-Gregory JK, Schär R, Schankin C, Gralla J, Pereira VM. Spontaneous intracranial hypotension: searching for the
CSF leak. The Lancet Neurology. 2022 Feb 25.
Samanta D. Headaches in Loyes-Dietz Syndrome. J Child Neurol 2019; 34: 144–7.
Pichott A, Bernstein T, Guzmán G, Fariña G, Aguirre D, Espinoza A. Dural ectasia and intracranial hypotension in marfan syndrome. Rev Chil Pediatr 2020; 91: 591–6.
4. Clinical Presentation
Orthostatic headache; less apparent over time,
making correct diagnosis more challenging
Non-orthostatic forms of headache include
thunderclap, non-positional, exertional, cough-
related, and “second-half-of-the-day
Any patient with unexplained chronic headache
should be evaluated for potential SIH
Häni L, Fung C, Jesse CM, et al. Insights into the natural history of spontaneous intracranial hypotension from infusion testing. Neurology 2020; 95: e247–55.
Mokri B, Aksamit A, Atkinson J. Paradoxical Postural Headaches in Cerebrospinal Fluid Leaks. Cephalalgia 2004; 24: 883–7.
5. Pathophysiology
Increased efflux of CSF in the upright position,
leading to traction on pain-sensitive fibers within the
dura mater
Vestibulo-cochlear disturbances may result from
negative intracranial pressure transmitted through
the patent cochlear aqueduct and perilymph leading
to endolymphatic hydrops and Meniere’s disease
6. Pathophysiology
Additional symptoms such as diplopia, dysgeusia,
and vestibulo-cochlear disturbances may also occur
and are related to brain sagging and traction on the
cranial nerves. This phenomenon is due to the
decrease in buoyant force normally provided by the
CSF, which under physiological conditions reduces
downforce of the brain and uplifts the structures
despite gravity
Idris Z, Reza F, Abdullah JM. Human Brain Anatomy: Prospective, Microgravity, Hemispheric Brain Specialisation and Death of a Person. In: Human Anatomy - Reviews and Medical
Advances. InTech, 2017: 62–87.
Yamamoto M, Suehiro T, Nakata H, et al. Primary low cerebrospinal fluid pressure syndrome associated with galactorrhea. Intern Med 1993; 32: 228–31.
9. Brain MRI (Bern Score)
Dobrocky T, Grunder L, Breiding PS, Branca M, Limacher A, Mosimann PJ, Mordasini P, Zibold F, Haeni L, Jesse CM, Fung C, Raabe A, Ulrich CT, Gralla J, Beck J, Piechowiak EI (2019)
Assessing spinal cerebrospinal fluid leaks in spontaneous intracranial hypotension with a scoring system based on brain magnetic resonance imaging findings. JAMA Neurol 76:580–587
10. Spine MRI
T2-weighted sequences show so-called spinal
longitudinal extradural fluid (contrast) (SLEC) in
60% of patients.
Luetzen N, Dovi-Akue P, Fung C, Beck J, Urbach H. Spontaneous intracranial hypotension: diagnostic and therapeutic workup. Neuroradiology. 2021 Nov;63(11):1765-72.
11. Diagnostic Algorhytm
Luetzen N, Dovi-Akue P, Fung C, Beck J, Urbach H. Spontaneous intracranial hypotension: diagnostic and therapeutic workup. Neuroradiology. 2021 Nov;63(11):1765-72.
12. Luetzen N, Dovi-Akue P, Fung C, Beck J, Urbach H. Spontaneous
intracranial hypotension: diagnostic and therapeutic workup.
Neuroradiology. 2021 Nov;63(11):1765-72.
13. Farb RI, Forghani R, Lee SK, Mikulis DJ, Agid R. The
venous distension sign: a diagnostic sign of intracranial
hypotension at MR imaging of the brain. American
Journal of Neuroradiology. 2007 Sep 1;28(8):1489-93.
14. Farb RI, Forghani R, Lee SK, Mikulis DJ, Agid R. The venous distension sign: a diagnostic sign of intracranial hypotension
at MR imaging of the brain. American Journal of Neuroradiology. 2007 Sep 1;28(8):1489-93.
15. Complications
Formation of subdural hematomas
Transtentorial herniation with compression of the
diencephalon and traction on cerebral sinuses
resulting in deep venous thrombosis decreased
level of consciousness and coma
Brain superficial siderosis
Nonconvulsive status epilepticus
Cognitive decline (frontotemporal brain sagging
syndrome)
Dobrocky T, Nicholson P, Häni L, Mordasini P, Krings T, Brinjikji W, Cutsforth-Gregory JK, Schär R, Schankin C, Gralla J, Pereira VM. Spontaneous intracranial hypotension: searching for the
CSF leak. The Lancet Neurology. 2022 Feb 25.
16. Differential Diagnosis
Dobrocky T, Nicholson P, Häni L, Mordasini P, Krings T, Brinjikji W, Cutsforth-Gregory JK, Schär R, Schankin C, Gralla J, Pereira VM. Spontaneous intracranial hypotension: searching for the
CSF leak. The Lancet Neurology. 2022 Feb 25.
17. Treatment
Multidisciplinary setting by neurologists,
neuroradiologists and neurosurgeons
Conservative: bed rest and caffeine
Percutaneous treatment with epidural patching
(targeted or non-targeted)
Surgical or endovascular closure of the CSF leak or
fistula
Dobrocky T, Nicholson P, Häni L, Mordasini P, Krings T, Brinjikji W, Cutsforth-Gregory JK, Schär R, Schankin C, Gralla J, Pereira VM. Spontaneous intracranial hypotension: searching for the
CSF leak. The Lancet Neurology. 2022 Feb 25.
18. Treatment
Epidural blood patching in patients with SIH often
fails to provide permanent relief
Surgical repair of spinal CSF leaks can be curative
but requires precise preoperative leak localization
Spinal CSF-venous fistulas typically do not resolve
with blood patching and instead require surgical
obliteration or endovascular embolization
Dobrocky T, Nicholson P, Häni L, Mordasini P, Krings T, Brinjikji W, Cutsforth-Gregory JK, Schär R, Schankin C, Gralla J, Pereira VM. Spontaneous intracranial hypotension: searching for the
CSF leak. The Lancet Neurology. 2022 Feb 25.
19. Summary
Orthostatic headache
Brain and spine MRI
Low lumbar puncture opening pressure is not a
reliable marker of SIH
Consider a spinal CSF-leak in non-geriatric patients
with non-traumatic (bilateral) subdural hematoma
