851.55 — Cerebellar or brain stem contusion with open intracranial wound, with prolonged [more than 24 hours] loss of consciousness without return to pre-existing conscious level

851.55 is an ICD-9-CM diagnosis code for cerebellar or brain stem contusion with open intracranial wound, with prolonged [more than 24 hours] loss of consciousness without return to pre-existing conscious level. ICD-9-CM was retired for U.S. claims on October 1, 2015, when ICD-10-CM took over.

The CMS General Equivalence Mappings translate it to 7 ICD-10-CM codes, such as S01.90XA (Unspecified open wound of unspecified part of head, initial encounter), S06.376A (Contusion, laceration, and hemorrhage of cerebellum with loss of consciousness greater than 24 hours without return to pre-existing conscious level with patient surviving, initial encounter) and S06.377A (Contusion, laceration, and hemorrhage of cerebellum with loss of consciousness of any duration with death due to brain injury prior to regaining consciousness, initial encounter). All of these are approximate matches, so review the record to pick the right one. Some mappings are combinations: more than one ICD-10 code is needed to fully express the ICD-9 code.