Wanted to tuck this in here instead of creating a new topic.
It's a paper comparing different imaging techniques
for MRI/MRA/MRV's, specifically in children.
I wonder if any of these dear ones are heading
for MS later in life due to the stenoses, and
underdevelopment of the veins that were found.
Too bad there's no way to track them. http://radiology.rsna.org/content/235/3/1011.full
Cerebral MR Venography in Children:
Comparison of 2D Time-of-Flight and
Gadolinium-enhanced 3D Gradient-Echo Techniques1
Figure 8. Oblique shaded surface rendering from 3D MR
venography data set in 3-year-old boy shows
right dominant transverse sinus and a
stenosis of the sigmoid sinus (arrow);
the stenosis was not apparent at
2D MR venography.
DISCUSSIONThe larger venous structures draining the brain
may be studied noninvasively at MR imaging by using
phase-contrast techniques, time-of-flight techniques,
and contrast material–enhanced 3D sequences (1–7).
Phase-contrast MR angiography is limited by
gradient imperfections, eddy currents, and long acquisition times
and potential lack of sensitivity to slow flow if the
selected velocity encoding is incorrect (2,6).
Two-dimensional time-of-flight MR venography suffers
from progressive signal loss caused by slow-flowing protons
and by the flow of protons parallel to rather than
perpendicular to the imaging plane; both of these
phenomena result in spin saturation (3).
Gadolinium chelate reduces the spin saturation and
is best administered as a bolus to avoid enhancement
of chronically thrombosed venous structures;
enhancement of such structures may simulate
the appearance of a patent venous sinus
Techniques for bolus injection of gadolinium chelate with
subsequent acquisition of images with a 3D rapid
gradient-echo sequence have been described
previously for the imaging of intracranial venous
anatomy in adults (5,6).
This is meant in the vein (no pun intended) of
"just because they say it's not there, does not mean it's not there".
Imaging is an imperfect picture, results are open to interpretation.
Properly conducted ultrasound showing reflux will hopefully, someday,
become the gold standard for screening.