• Clinical syndrome with a wide variety of clinical presentations related to the spontaneous leakage of cerebrospinal fluid (CSF) in the spine leading to CSF hypovolemia
• Related to decreased CSF volume, not pressure
• Estimated annual incidence of 5 per 100,000
• Approximately half as common as aneurysmal subarachnoid hemorrhage
• Mean age 42.5 years, 63% female
Most common clinical manifestation is orthostatic headache.* Headache may begin as orthostatic and become non-orthostatic.
Location and quality are highly variable. Some are exertional or second-half-of-the-day.
May worsen with Valsalva.
Other non-headache signs and symptoms:
Neck and interscapular pain
Tinnitus, dizziness, change in hearing
Nausea and emesis
Cognitive and behavioral abnormalities, including a dementia-like presentation
Encephalopathy, coma, stupor
Bibrachial amyotrophy (lower motor neuron disorder confined to the upper limbs)
Headache thought to be due to traction on meningeal layers and venous engorgement.
*Not all patients with orthostatic headache are related to CSF leakage.
Arachnoid herniation through dural defect near nerve root
CSF-to-Venous Fistula
• Subdural Fluid Collections
• Enhancement of the Pachymeninges
• Engorgement of the Venous Structures
• Pituitary Hyperemia
• Sagging of the Brain
• Important to note negative brain imaging does NOT exclude SIH.
• Up to 20% of SIH patients have normal brain imaging.
• Performed prone (ventral dural tears) or decubitus (lateral dural tear and CSF venous fistulas)
• Total spine MR reviewed prior to dynamic myelogram with attending to decide positioning.
1. Patient positioned prone with hips elevated using wedge air mattress.
• Ensure appropriate slope to overcome thoracic kyphosis
2. Perform planning scan, pick LP site
3. Mark, prep and drape patient
4. Perform CT fluoro-guided LP
5. Confirm intrathecal access and prepare scanner for diagnostic scans
6. Amount and frequency of contrast injected determined by attending during procedure
1. Patient positioned decubitus with hips elevated using pillows
• Ensure appropriate slope
• Beginning side based on review of total spine MR with attending
2. Perform planning scan, pick LP site
3. Mark, prep and drape patient
4. Perform CT fluoro-guided LP
5. Confirm intrathecal access and prepare scanner for diagnostic scans
6. Amount and frequency of contrast injected determined by attending during procedure
