<prompt> Onodi cells and Haller cells are seen in relation tooptic nerve and floor of orbitOptic nerve and frontal sinusOptic nerve and ethmoidal air cellsOrbital chiasma and Nasolacrimal duct  <response>: The onodi cells and haller cells are posterior ethmoidal air cells. Onodi cell: Posterior ethmoidal cell which may grow posteriorly by the side of sphenoid sinus or superior to it for as much distance as 1.5 cm from the anterior surface of sphenoid. Hallercells: Air cells situated in the roof of maxillary sinus. Ref.Dhingra 5e,p 153. 