Optic neuropathy and acute visual loss caused by an isolated mucocele of an Onodi cell
have been reported.
This is important because approaching laterally and superiorly through the lateral portion of the ethmoid sinus could easily injure the optic nerve, or in the case of an Onodi cell
, cause entry into the intracranial cavity.
Dissection of the left posterior ethmoid cells revealed the presence of a superior Onodi cell (sphenoethmoid cell) above the sphenoid sinus (figure, B).
The Onodi cell was first described in 1903 by Prof.
In a typical case of Onodi cell, one should look for a bulging of the optic nerve, which should run transversely along the superior portion of the posterior wall of the Onodi cell (figure, D).
Awareness of the presence of an Onodi cell or multiple Onodi cells is important prior to dissection in the sphenoethmoid area (7) The sphenoid sinus is normally situated behind the posterior end of the posterior ethmoid sinus.
Relationship of Onodi cell to optic neuritis--radiological natomy on coronal CT scanning].
Endoscopic sinus surgery in patients who have an Onodi cell (sphenoethmoid cell) carries a high risk for optic nerve injury.
11,12) During such surgery, the posteriormost ethmoid air cell can undergo extensive pneumatization and come into close contact with or encroach on the optic canal, thus creating an Onodi cell (sphenoethmoid cell).
12) They studied 102 half-heads from 51 cadavers and found an Onodi cell in 52 half-heads (51.
In this article, we describe our study to determine the prevalence of an Onodi cell in adult Thai cadavers, to ascertain the prevalence of an overriding ethmoid cell, to measure the length of an overriding ethmoid cell's superior and posterior extensions in relation to the anterior sphenoid wall, and to determine the minimum amount of bone thickness between each Onodi cell and optic nerve.
In what year, according to Christmas et al (Rhinoscopic Clinic), was the Onodi cell