In head and neck cancer,<unk>  is a line that connects the medial canthus of the eye to the angle of the mandible. The line defines a plane orthogonal to a sagittal plane that divides the maxillary sinus into (1) an anterior-inferior part, and (2) a superior-posterior part. Tumours that arise in the anterior-inferior part, i.e. below<unk> , generally have a better prognosis than those in the other group. Addition to above a vertical line through pupil is also considered, which divides the above-mentioned structures into 4 different regions. The structures at posterosuperior medial have worst prognosis and that at anteroinferior medial are least dangerous.
Ohngren's line
Arlt's line
Sampaolesi line
Birmingham gauge
Blumensaat's line
Burton's line
Schwalbe's line
Hilgenreiner's line