The need for structured data in electronic health records has not been fully addressed by reference terminologies (RT) due to difficulties of use for end-users. Interface terminologies (IT), built for specific usage and users, and linked to RT, may solve this issue. We propose an IT for medical imaging prescription, based on the French nomenclature for procedure (CCAM), and its qualitative evaluation. The creation and evaluation processes were adapted from published guidelines. Prescription IT is available on the web (http://pts.chu-rouen.fr). It contains 290 orderable terms linked to 249 CCAM codes. The synonymy of prescription IT is significantly richer than the CCAM one and labels are significantly shorter. The main problem came from the CCAM, which is dedicated to billing purposes. We are planning to map prescription IT to other international RT such as RadLex or SNOMED. Prescription IT might quicken the adoption of computerized ordering processes in France.