IPA: /ˌɪntrəˈkreɪniəli/
KK: /ɪntrəˈkreɪnɪəli/
In a manner that relates to the inside of the skull.
The doctor explained the procedure that would be performed intracranially.
Intracranially → It is formed from "intra-" (meaning within) and "cranium" (from Greek "kranion", meaning skull) and the suffix "-ally" (meaning in a manner relating to). The word "intracranially" refers to something occurring within the skull.
Think of 'intra-' meaning 'within' and 'cranium' referring to the 'skull' — so intracranially means something happening within the skull.