Nose anatomy and sinuses. Coloured computed tomography (CT) scan of a frontal view through the nose of a 31 year old woman. At lower centre, channels formed by the nasal conchae reveal the internal anatomy of the nose. Two frontal sinuses (yellow) are seen above the nasal passages and these air-filled cavities lined with mucous membrane form some of the facial sinuses around the nose. The eye sockets with eyeballs (rounded) are visible as well as tissue of the brain (blue, at top) protected by the skull bones (white). The sinuses lighten the weight of the skull and improve the resonance of the voice.