I was diagnosed with this in 2016. My doctor’s notes suggest:

Better redemonstration and confirmation of 2.1 cm fusiform aneurysmal dilatation of the celiac artery. Associated occlusive dissection with thrombus formation likely within the false lumen involving the celiac artery, proximal common hepatic artery, and origin splenic artery. Etiology of this is unclear. This can be seen in association with underlying vasculitis. No other findings to suggest vasculitis as far as visualized.

I presented with similar symptoms, severe pain in low back with nausea. From onsite of initial pain (while sitting in my barber’s chair hoping he would finish quick because I needed to vomit) until the time I ended up in the ER was 90 minutes. Was on a Friday night. ER doctor sent me home, couldn’t find any reason for the pain. I suffered thought the Memorial Day week and was first in line to see my primary care doctor on Tuesday. He immediately sent me to a general surgeon who admitted me to the hospital (same one I had gone to on the Friday).

I was lucky that the general surgeon was a very experienced doctor with 40+ years of medical practice. He had seen this before and knew what to test and sent me to the vascular surgeon who explained to me “it is like you have wallpaper in the walls of your arteries. For some reason, the wallpaper is peeling from the top and blood is getting behind the wallpaper causing the issue”. Great explanation. The pain was explained as my spleen dying from lack of blood flow. Don’t know if that is a common symptom.

Was in hospital for four days, started on blood thinners (stayed on for 6 months) and re-scanned with no issues. Follow up visit in 2019, no issues.

If I can be of help to anyone here, please let me know.