Injury of olfactory nerve, left side, subsequent encounter

This code signifies a documented injury to the left olfactory nerve, responsible for the sense of smell, that is being treated or evaluated after the initial encounter. Such an injury can result in anosmia (loss of smell) or dysosmia (distorted smell) and may stem from trauma, surgery, or other neurological events affecting the first cranial nerve.

Apply this code when a patient presents for follow-up care, rehabilitation, or further evaluation of a previously diagnosed left olfactory nerve injury. Documentation should clearly indicate the left side of involvement and specify that the current visit is not the initial treatment for the acute injury.

• Ensure documentation specifies "left side" and the "subsequent encounter" for accurate code assignment.
• Distinguish from initial encounters (A) or sequela (S) codes for olfactory nerve injuries.
• Always review the medical record for the cause of the injury to potentially add an external cause code.