Just after some quick searches, I can't find any specific restrictions on air travel. However, I'd suggest asking your allopathic doctor (gasps, I know) on if there are any known issues.
Further, I'd suggest doing a LOT of online research on Hemangiomas and familiarizing yourself with as much information as you can concerning them. I found quite a lot by going to http://www.google.com and entering in [ hemangiomas liver ] in the search window. You can further narrow the search by adding on additional words like [ hemangiomas liver healing ] for information specific to your condition.