Basilar Perforator Aneurysm Perimesencephalic Hemorrhage

A collage of aneurysms…

In our experience, small basilar perforator aneurysms are present in the vast majority of patients with perimesencephalic-type hemorrhage. There are grading systems re how little or large the hemorrhage is etc. The more blood the more the chance of finding a more classic source. The problem with that theory is that it presumes that “true” perimesencephalic bleeds are “nonaneurysmal”. This is an example of circular reasoning type of logical fallacy. They are only nonaneurysmal insofar as an aneurysm is not identified — not because its really true. In fact, it is false — the aneurysms are there — you just need better imaging to see them.

Below are several examples

HR-CBCT (DYNA)

MIPs — see anything?

Finding was not appreciated. Repeat angio in 1 week — see below. Both under general anesthesia

Thats what they look like. Very real and that’s the cause

Another case — this is a more obvious one…

Nothing below…

Or here

Now for the DYNA — nothing from the basic one

How about a secondary, more detailed reconstruction

Now we can see on delayed imaging DSA — and only because its a big one

Case 3 below:

Day 11

Day 15 — here is the cause

Anaglyph stereo

Treated this one

Convinced yet?

The overall prognosis is of course excellent. But that does not mean we should not try to find out what the cause is, and why they happen.