This CPB has been revised to state that: (i) magnetic resonance imaging (MRI) for Morton neuroma is considered medically necessary for pre-operative planning when symptomatic neuroma has been identified by plain X-ray and non-surgical treatments (e.g., metatarsal support, padded shoe insert, and steroid/local anesthetic injections) have failed; and (ii) knee MRI for fitting of implants for total knee arthroplasty is considered experimental and investigational.