--stands for Anterior Cervical Disectomy and Fusion. (Also Aggregated Coastal Diffusion Fisheries, but I don't think that's a neurological condition. )

Good to have you at Neurotalk; have you taken a look at our collection of info and expertise at the Spinal Disorders forum yet?

http://neurotalk.psychcentral.com/forum22.html

How many and at what levels is this being done?