Hopefully in the next few years, the medical field or literally just anything money-related will recognize bitcoin or at least cryptocurrencies in general as payments. There is quite a number of users, and is able to grow even more, of bitcoin. Main problem is its difficulty to spend it as for its volatility.
It will finally have in the coming years to come, so we don't need to worry about it because for sure there are already people or company who sees this kind of opportunity and to put it in a medical billing, it will really have if we will just have the patience of waiting.