Head and Neck
Onodi cells and Haller cells of ethmoid labyrinth seen in relation to following respectively (AIIMS Nov’2009/ AIPG – 2011)
|A||Optic nerve & floor of orbit|
|B||Optic nerve & Internal carotid artery|
|C||Optic nerve and naso lacrimal duct|
|D||Orbital floor and nasolacrimal duct|
1. Onodi cell is the most posterior ethmoidal cell that is present superior & lateral to the sphenoid sinus and is intimately related to the optic nerve and internal carotid artery.
2. Optic nerve may be seriously damaged in ESS (Endoscopic sinus surgery).
3. Haller cell represent an extension of anterior ethmoidal air cells extending into the infra-orbital margin (roof of maxillary sinus) that is floor of orbit.