Fig. 2.

Theorised impacts of bone flap displacement on planning margins. A) Clinical Target Volume (CTV; orange) defined in relation to skull bone, B) potential change in CTV with extracranial displacement, C) potential change in CTV with intracranial displacement, D) and measurement (red arrow) between the brain OAR and bone flap. Resection cavity; black, skull bone; blue, brain OAR; purple. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)