What is disclosed is an artificial cranial operculum (1) to replace a bone operculum (2) removed from a cranial theca (7) during a neurosurgical procedure that involves a craniotomy. The artificial cranial operculum (1) is made of material that is rigid, biocompatible, sterilizable, and compatible with ultrasound and with nuclear magnetic resonance. Preferably the artificial operculum is made of polymethylpentene.
