The frontal air sinus are situated behind the brow ridges. Sinuses are mucosa-lined airspaces within the bones of the face and skull. Each opens into the anterior part of the corresponding middle nasal meatus of the nose through the frontonasal duct which traverses the anterior part of the labyrinth of the ethmoid. These structures then open into the hiatus semilunaris in the middle meatus.
Knowledge of frontal sinus morphometry is important in bifrontal craniotomy, pterional craniotomy, orbitozygomatic craniotomy, and supraorbital craniotomy. Inadvertent frontal sinus violation can lead to infection, cerebrospinal fluid fistula, and mucocele formation. In particular, knowledge of anatomy in relation to surgically relevant landmarks can help surgeons perform these procedures more precisely and safely.
Image-guided craniotomies based on 3D volumetric image rendering allow for fast and reliable demarcation of complex anatomical structures hidden from direct view in frontolateral approaches. The outline of the frontal sinus and the orbit can be appraised at a glance providing additional safety and precision during craniotomy 1).