Keywords:
Cerebrospinal fluid, Technical aspects, Imaging sequences, Diagnostic procedure, MR, Neuroradiology spine, Neuroradiology brain
Authors:
A. Saiz1, J. Sanz DÃaz1, J. Peña Suarez1, E. Santamarta1, L. MartÃnez1, C. Suárez Arcay1, �. Meilán MartÃnez1, D. Villegas2, M. alvarez1; 1Oviedo/ES, 2Zacatecas/MX
DOI:
10.26044/ecr2019/C-1853
Methods and materials
We retrospectively review the last cases of spinal cord deformities done at our institution from August 2014 through September 2018.
The spinal MRI protocol benefits from high field equipment,
to guarantee the highest resolution.
So,
all MRI studies were performed on a new generation 3T MRI scanner (Table1).
Eighteen patients,
including both symptomatics and asymptomatics,
were examined using anatomic sequences consisted of sagittal T1-weighted,
sagittal and axial T2-weighted turbo spin-echo (TSE),
and STIR sequences to rule out myelopathy.
We also performed a morphological study of the cord by using a high resolution anatomical examination consisted of heavily T2-weighted 3D-SPACE images.
This sequence is useful to look for transdural herniation,
and directed visualization of the archnoid web.
To demonstrate the presence of alterations of the CSF flow dynamics,
we performed sagittal Cine Phase contrast MRI imaging in sagittal plane. Before PC MRI data are acquired,
we initially performed a velocity test with three velocity encoding VENC (2-4-7 cm s−1 for standard spinal CSF flow imaging) to optimize the final acquisition. To obtain the optimal signal,
the CSF flow velocity should be the same as,
or slightly less than,
the selected VENC.
When VENC is lower can produce local aliasing artefacts,
whereas when it is greater result in a weak signal.
Low VENC values (2–4 cm s−1) can be helpful when local flow is low and in the discrimination of communicating and non-communicating arachnoid cysts when present.
The arachnoids webs can produce significantly higher VENC values with presence of aliasing artefacts.
We also preformed a cardiac-gated MRI cine TRUE-FISP imaging in two planes,
sagital and axial,
to improve the directed visualization of the archnoid web in dynamic way in comparition with heavily T2-weighted 3D-SPACE images.
All these sequences allow us to identify the changes in the physiological movement of spinal cord and the related areas with greater turbulence of CSF,
improving the surgical approach by avoiding extensive laminectomy.
(Fig.
4)(Fig.
5)