Kansas Subscriber
Answer: ICD-9 advises coders to report ICD-9 799.89 (Other ill-defined and unknown causes of morbidity and mortality; other ill-defined conditions) for cerebral hemiatrophy, so you should report this code for DDM as well.
Dyke-Davidoff-Mason syndrome (DDM) is also referred to as a cerebral hemiatrophy, a genetic condition that results in facial asymmetry.
Remember that you should not report this code unless the radiologist documents that the patient actually has DDM. If he refers to "probable," "potential" or "suspected" DDM, you should code the symptoms rather than the DDM diagnosis.