Thanks for using the forum. I am happy to address your questions, and my answer will be based on the information you provided here. Please make sure you recognize that this forum is for educational purposes only, and it does not substitute for a formal office visit with a doctor.
Without the ability to examine and obtain a history, I can not tell you what the exact cause of the symptoms is. However I will try to provide you with some useful information.
I cannot provide information on whether you are safe to travel or not. You will need to discuss with your primary physician. The question, I have is why are you having TIAs? Have you had an MRI of the brain, vessel imaging of your neck and head, cardiac echo, and risk factor minimization (such as controlling blood pressure, blood sugars, lipis, smoking cessation, etc). Given your hemangiomas, I would be concerned that the events you are having are seizures.
Again, you should discuss your symptoms with your primary physician and have him/her provide information on safety of flying.
Thank you for this opportunity to answer your questions, I hope you find the information I have provided useful, good luck.
I also have a cavernous hemangioma which has had several small bleeds and one major bleed, resulting in permanent numbness and balance problems. The major bleed was almost 5 years ago and I was told at that time not to fly. I have not had any major strokes in the past 5 years but I have frequent severe headaches and seizures. My cav. hem. is in the motor cortex so surgery is not an option. Recently my doctor said it is OK to fly. Is that because it has been pretty stable for several years? Or maybe the doctor forgot that he told me I should not fly before? Does the change in air pressure when flying present additional risk with this condition. I'm not asking you to diagnose me or give an opinion on me flying- I just want to know if there is a scientific reason why flying would or would not be more dangerous with this condition.