Non-invasive Magnetic Resonance
Myelography in Spontaneous Spinal
Cerebrospinal Fluid (CSF) Leak
Adam Liudahl, MD
Diagnostic Radiology Resident
Bruno Policeni, MD
Staff Neuroradiologist
Toshio Moritani, MD
Staff Neuroradiologist
Aristides A. Capizzano, MD
Staff Neuroradiologist
University of Iowa Hospitals & Clinics, Iowa City, IA
Control #479; eEdE-231
Financial Disclosures
• Authors have no financial disclosures to report
Outline
•
•
•
•
•
Background
Anatomy
Review of available imaging modalities
Studies in the literature
Case Examples
Spontaneous Spinal CSF Leak
• Alternatively, Spontaneous intracranial hypotension,
Cerebral spinal fluid (CSF) leak, spontaneous CSF
hypovolemia.
• Syndrome consisting of a constellation of
neurological symptoms (most commonly postural or
orthostatic headache) and a CSF leak within the
spinal axis
Spontaneous Spinal CSF Leak
• Exact cause unknown. *CSF leaks can occur
from iatrogenic causes and uncommonly from
intradural osteophyte leading to spinal dural
tear.
• Possible cause is structural weakness of the
spinal meninges, but likely multifactorial.
• CSF leak size is variable ranging from minimal
amount during Valsalva to large amounts in
paraspinal regions.
Spontaneous Spinal CSF Leak
• No large scale study examining incidence or
prevalence
• Estimated at 5 per 100,000 in 2003/04 study
• Female predominance, M:F of 2:1.1
• Typically in 30-50 years of age; peak incidence
around 40 years old
Definition/Diagnostic Criteria
Definition: Symptomatic leakage of CSF.
Diagnostic criteria for headache attributed to spontaneous
intracranial hypotension (SIH), according to
International Classification of Headache Disorders, 3rd edition
(ICHD-3):
A) any headache fulfilling criteria B through D
B) low CSF pressure (<60 mm H20) and/or evidence of CSF leakage
on imaging
C) headache has developed in temporal relation to the low CSF
pressure or CSF leakage, or has led to its discovery
D) not better accounted for by another ICHD-3 diagnosis
Diagnostic Criteria
Proposed diagnostic scheme by Schievink et.al to encompass a wide
spectrum of clinical and radiographic manifestations of spontaneous spinal
CSF leaks and intracranial hypotension
Schievink WI, Maya MM, Louy C, et al. Diagnositic criteria for spontaneous spinal CSF leaks and intracranial
hypotension. American Journal of Neuroradiology, 2008;29(5):853-856.
Treatment
• Conservative treatment
– Bedrest, hydration and analgesics
• Epidural blood patch
– Autologous blood or Fibrin glue sealant
– Simple mass effect (both) & clotting (blood)
– “Directed” patch more efficacious
Spinal Anatomy
Schievink WI. Spontaneous spinal cerebrospinal fluid leaks and
intracranial hypotension. Jama 2006;295:2286-2296
CSF hydrodynamics
- Traditional Model
- New Model
• CSF produced by choroid
plexuses
• Flow from ventricles to
subarachnoid spaces
• Resorbed by arachnoid villi
• CSF produced and resorbed by
the entire CSF-interstitial fluid
unit
• Choroid plexuses, arachnoid villi
and lymphatics have minor
roles
• Formation and resorption
occurs across walls of CNS blood
capillaries
• CSF volume depends on
hydrostatic and osmotic forces
between capillaries and CSFinterstitial fluid unit
Monroe-Kellie hypothesis: the sum
of the volumes of intracranial
blood, CSF and cerebral tissue
must remain constant.
Imaging options
•
•
•
•
•
CT myelography
Radioisotope cisternography
Non-invasive MR myelography
Suggestive MR brain findings
Conventional Spinal MR
CT myelography (CTM) overview
• Myelography with subarachnoid iodinated
contrast followed by CT of entire spine.
• Define location and extent of CSF leak
– Exact location can be difficult
– Meningeal defects, extradural collections
& relationships to bony structures
• Only detect active (high flow) CSF leak
• Entire spine radiation exposure
Contrast along the nerve root right T10-11 (blue)
Radioistope Cisternography (RIC)
• Only can detect active CSF leakage
– Indirect findings (~30% cases no direct
signs):
•
•
•
•
Early visualization of bladder activity*
No activity over brain convexities
Rapid disappearance of spinal activity
Abnormal visualization of root sleeves
Tracer visualized at the
• Long exam time
level of T4 bilaterally (red)
• Invasive exam
• Reported sensitivities are wide-ranging
Non-Invasive MR myelography (MRM)
• T2 weighted images are the basic sequence
in visualization of potential CSF leak.
However, T2 with fat saturation or STIR is
need to detect small fluid collections.
• MR myelography using heavily T2 weighted
3 D sequence (SPACE or HASTE with fat
saturation) shows site as well as orientation
of CSF leak channel
• Enhance CSF signal by suppressing adjacent
tissue signal
• Leak may appear as CSF space expansion
around nerve root sleeves
Normal MRM
Indirect MRI Brain Findings
•
•
•
•
•
Subdural fluid collections (white)
Pachymeningeal enchancement (blue)
Brain sagging (green)
Venous structure engorgement (yellow)
Pituitary hyperemia (red)
MR Spine Findings
•
•
•
•
•
•
Spine fluid collection
C1-C2 sign
Floating dural sac sign
Dural enhancement/Dilated epidural veins
Meningeal diverticulum/Perineural cysts
Pseudomeningocele
C1-C2 Sign
• CSF accumulates in
the space between
C1 and C2 spinous
processes
• Does not
necessarily denote
site of leak
• “False localizing
sign”
T2W sequence
3D SPACE w/ fat sat
aka MRM
Floating Dural Sac Sign
- A hyperintense
band or rim around
the spinal thecal sac
on axial T2W images
is suggestive of CSF
Leak
Dural Enhancement/Dilated epidural
veins
-Smooth and circumferential enhancement
-Concomitant intracranial dural enhancement not always seen
-CSF volume decreases causing compensatory vasodilation in
attempt to maintain stable pressure (Monro-Kellie doctrine)
-Can be seen in dural arteriovenous fistulas
Meningeal diverticulum/ Perineural cyst
- May predispose to rupture/CSF leak
- Proposed areas of dural weakness
Multiple perineural cysts
on 3D HASTE (right).
Axial T2 weighted image
showing right perineural
cyst at T3-T4 (left).
T3-T4
Right T2-T3 CSF Leak
Young female who presented with headache. 3D SPACE myelogram demonstrates
right T2-T3 CSF leak (blue) and multiple meningeal cysts/diverticula (yellow)
Pseudomeningocele
- Post-traumatic CSF collection communicating with thecal sac
Pseudomeningocele (blue)
extending from T7/8 – T11/12
Non-Invasive MR Studies From The
Literature
• Tomoda, et al. (2008)
– 27 patients
– Comparison made to radioisotope cisternography (RIC)
• Wang, et al. (2009)
– 19 patients
– Comparison to computed tomographic myelography
(CTM)
• Yoo, et al. (2008)
– 15 patients
– Comparison made to radioisotope cisternography (RIC)
Tomoda, et al. (2008)
• Retrospective study involving 27 patients
• 3D FSE MR myelography with RIC
– 1.5T; TR 6000ms; TE 203.7 ms
• Conclusion: 3D FSE MRM useful in spinal CSF leak detection
and may be initial test of choice
Tomoda Y, Korogi Y, Aoki T, et al. Detection of cerebrospinal fluid
leakage: initial experience with three-dimensional fast spin-echo
magnetic resonance myelography. Acta Radiologica 2008;49:197-203
Wang, et al. (2009)
• Prospective study with 19 patients
• SSFSE (Heavily T2W) MRM compared to CTM
– 1.5 T
• Results (detection rates did not differ)
– Along nerve roots (84% v 74%, p = 0.25)
– High cervical retrospinal (32% v 16%, p = 0.13)
– Epidural CSF collection (89% v 79%, p = 0.20)
• Conclusion: MRM accurate in CSF leak localization and
alternative to CTM
Wang Y-F, Lirng J-F, Fuh J-L, et al. Heavily T2-weighted MR myelography vs
CT myelography in spontaneous intracranial hypotension. Neurology
2009;73:1892-1898
Yoo, et al. (2008)
• 15 patients
• 2D TSE compared to RIC
– 1.5 T; TR 8000ms; TE 1000ms
• Results
– Agreement among two readers between MRM & RIC
(kappa = 0.634 & 0.444)
• Conclusion: MRM can be used as screening tool
Yoo H-M, Kim S, Choi C, et al. Detection of CSF leak in spinal CSF leak syndrome using
MR myelography: correlation with radioisotope cisternography. American Journal of
Neuroradiology 2008;29:649-654
Non-Invasive MR Myelography
• Consists of the following spinal sequences
– Sagittal T2, Sagittal T1
– Axial T2, Axial Diffusion, Axial STIR
– 3D Haste or 3D SPACE Myelogram*
– Sagittal and Axial T1 fat-suppression post contrast
• TR 3000.00ms; TE 430.00ms*
Ex #1; + RIC, - MR (not MRM)
Radioisotope cisternography images (below) demonstrating
multilevel thoracic and lumbar spinal CSF leaks.
Multiple axial T2 images in at different levels (right) in this
same patient which do not show signs of spinal CSF leak.
Ex #2; + RIC, - MR initially, +MRM
T2 weight axial
Radioisotope cisternography
Patient with right sacral CSF
leak which is not well
demonstrated on initial
conventional MR spine.
Patient brought back for
dedicated CSF leak protocol.
Positive on RIC imaging.
R
Ex #3; + RIC, + MRM
MRM study showing
corresponding
multilevel thoracic
spine CSF leaks.
Positive RIC study showing
multilevel CSF leaks in the
thoracic spine
Summary/Conclusion
• Non-invasive magnetic resonance
myelography is a first-line tool for diagnosing
spinal cerebrospinal leaks in spontaneous
intracranial hypotension.
•
•
•
•
•
•
•
•
•
•
References
1.
Schievink WI. Spontaneous spinal cerebrospinal fluid leaks and intracranial hypotension. Jama
2006;295:2286-2296
2.
Tomoda Y, Korogi Y, Aoki T, et al. Detection of cerebrospinal fluid leakage: initial experience with
three-dimensional fast spin-echo magnetic resonance myelography. Acta Radiologica 2008;49:197-203
3.
Wang Y-F, Lirng J-F, Fuh J-L, et al. Heavily T2-weighted MR myelography vs CT myelography in
spontaneous intracranial hypotension. Neurology 2009;73:1892-1898
4.
Yoo H-M, Kim S, Choi C, et al. Detection of CSF leak in spinal CSF leak syndrome using MR
myelography: correlation with radioisotope cisternography. American Journal of Neuroradiology
2008;29:649-654
5.
Schievink WI, Maya MM, Louy C, et al. Diagnositic criteria for spontaneous spinal CSF leaks and
intracranial hypotension. American Journal of Neuroradiology 2008;29(5):853-856.
6.
Chikly B, Quagheber J. Reassessing cerebral fluid (CSF) hydrodynamics: A literature review
presenting a novel hypothesis for CSF pathology. Journal of Bodywork & Movement Therapies
2013;17:344-354
7.
Medina JH, Abrams K, Falcone S, et al. Spinal Imaging Findings in Spontaneous Intracranial
Hypotension. American Journal of Roentgenology 2010;195:459-464
8.
Amoozegar F, Guglielmin D, Hu W, Chan D, Becker WJ. Spontaneous intracranial hypotension:
recommendations for management. The Canadian Journal of Neurological Sciences 2013;40(2):144-157
9.
Thomas D, Menda Y, Graham M. Radionuclide Cisternography in Detecting Cerebrospinal Fluid
Leak in Spontaneous Intracranial Hypotension: A Series of Four Case Reports. Clinical Nuclear Medicine
2009;34(7)410-416.
10.
Hosoya T, Hatazawa J, Sato S, et al. Floating Dural Sac Sign is a Sensitive Magnetic Resonance
Imaging Finding of Spinal Cerebrospinal Fluid Leakage. Neurologia Medico-Chirurgica 2013;53(4):207-212.