@birdman518 The tests for TOS do not need to be MRIs. At Mayo, they confirmed my TOS with small blood pressure cuffs on my fingers and had me move my arm into different positions. They also did doppler readings to see how blood flow changes with different arm positions and with turning your head. The doctor also listened to my pulse in my neck and had me turn my head. What happens is that cuts off blood flow with raising your arm or turning your head. There are several places of compression with TOS between scalene muscles, between the collar bone and rib cage, and under pec minor. I did have an MRI years ago that showed some inflammation in the area where the brachial plexus (nerve bundle) passes through the thoracic outlet. There wasn't a lot visible on the MRI, so the diagnosis is made through testing and exams. If your neurologist doesn't seem familiar with this, you need to get an opinion somewhere else where there are specialists for TOS. If your doctor has confirmed a nerve problem in your arm that is urgent, you can wait on testing for TOS. I wanted you to be aware that it's possible to be misdiagnosed which could put you through an unnecessary surgery that doesn't fix the problem. I read that TOS patients can go many years before getting a correct diagnosis and I was blamed for malingering after carpal tunnel surgery by a hand surgeon who missed it completely. It is glossed over in medical school (according to my neurologist) in a day and many doctors think it is rare. It's not rare, but getting the correct diagnosis can be. It can be caused by a whiplash and for that reason it is probably more common among people with spine issues. You might want to search for some providers who treat TOS in your area so you are prepared just in case.