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Non-fluoroscopic Catheter Tracking for Fluoroscopy Reduction in Interventional Electrophysiology
Published on: May 26, 2015
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C1 Posterior Arch Flare Point: A Useful Landmark for Fluoroscopically Guided C1-2 Puncture
M E Peckham1, L M Shah2, A C Tsai2
1From the Departments of Radiology and Imaging Sciences (M.E.P., L.M.S., A.T., E.P.Q., T.A.H.), University of Utah, Salt Lake City, Utah Miriam.Peckham@hsc.utah.edu.
AJNR. American Journal of Neuroradiology
|June 23, 2018
Summary
A new "flare point" landmark on C1-2 intrathecal puncture aids needle placement, improving safety and accuracy. This osseous landmark helps avoid cervical cord injury during the procedure.
Area of Science:
- Neurosurgery
- Radiology
- Anatomy
Background:
- C1-2 intrathecal puncture is an alternative when lumbar puncture is not feasible.
- Decreased usage is linked to concerns about cervical spinal cord injury.
- Current fluoroscopic guidance lacks precision for needle placement.
Purpose of the Study:
- To introduce a novel osseous landmark for C1-2 intrathecal puncture.
- To define the
- flare point
- as a guide for needle positioning.
- To improve the safety and accuracy of C1-2 intrathecal puncture.
Main Methods:
- Review of 42 cervical spine CT myelograms.
- Reformatting images to simulate lateral fluoroscopy.
- Identification and measurement of the
- flare point
- relative to the spinal cord.
Main Results:
- The
- flare point
- was an average of 0.2 mm posterior to the spinal cord.
- In 37 out of 42 subjects, the landmark was posterior to the spinal cord.
- 16 C1-2 punctures using the technique were performed without complications.
Conclusions:
- The C1 posterior arch
- flare point
- accurately approximates the dorsal spinal cord margin.
- Targeting using the
- flare point
- enables safe and optimal needle positioning at the C1-2 interspace.
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