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Date of last update: 10/04/2017.

Forum Name: Neurology Topics

Question: Trifurcation Bifurcation MCA CTA

 speltback - Wed Jan 14, 2009 1:38 pm

I had an MRA of the brain that showed a possible aneurysm in the region of the MCA trifurcation. We did a follow up CTA that came back negative but the report read that there was no evidence of aneurysm in the region of the MCA "bifurcation." It did not mention "Trifurcation" as the first report did.

When I asked my neurologist about the use of the word "Trifurcation" in the MRA report and then "bifurcation" in the CTA report, he told me the terms are more or less synonymous and that different people call the area different things. Is he correct? Should there be further investigation into the area of "Trifurcation?" Did the reader of the CTA miss something or make a typo?

Thank you so much.
 John Kenyon, CNA - Wed Feb 11, 2009 11:22 pm

User avatar Hello -

It seems you got two very different results, so I would definitely go for a tiebreaker. Seriously. If the radiologist reading the first one saw a "trifurcation" then it was a three-way branching of the vessel. The second one, via CTA, visualized only a fork in the vessel, and no suggestion of aneurysm. These are findings different enough to be irreconcilable, and I sincerely believe, although your doctor seems to feel it's not important, that another MRA (I believe this to be the preferable imaging method for this area) should be performed. Whichever of the first two it most resembles should be the accepted finding. If your doctor is unwilling to order the additional test, I'd look for a second opinion, at least, on the discrepancy. The second test gave a much better result, and "possible" is, of course, only that, but I just don't feel right about such a big variance in findings, and happen to trust MRA/MRI more in this instance.

Hope this is helpful. Best of luck to you. Please keep us updated.

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