Here is my logo for your consideration. Eye-catching and memorable, yet simple enough to look great at small scales (such as business cards, brochures, etc.). The brain echoes the play on words and your clever approach to what you do, while also emphasizing the most important part: billing.
I have submitted a 2nd version with a different font. The first set of logos (#70, #71, #72) has a very traditional Medical-related font, whereas the second set of logos (#73, #74, #75) has a more modern-feeling font.