A few ICD-9 diagnosis codes include 383.81 (postauricular fistula), 383.9 (mastoiditis nos) and 383.32 (postmastoid cholesteatma) according to the EICD software site. ICD-9 diagnosis codes can be looked up on the government sponsored Centers for Medicare & Medicaid Services website.
The ICD-9 is known as the International Classification of Diseases and the 9 denotes the ninth edition according to the American College of Emergency Physicians. The ICD-9 codes are used by hospitals, doctors and health professionals to denote diagnosis classifications for billing needs, insurance needs and for identification needs. It also helps to keep diagnostic information private and abides by the HIPAA rules and regulations. The ICD was first used in 1893 and has been updated routinely ever since notes the American College of Emergency Physicians. As of 2015, there are three volumes in the ICD-9 collection.