Frontal intersinus septal cells
Frontal intersinus septal cells, also known as interfrontal sinus septal cells, are a subtype of medial frontal recess cells.
Gross anatomy
The frontal intersinus septal cells lie within the intersinus septum between the frontal sinuses. They usually drain in the medial aspect of the frontal recess.
When extensively pneumatized, aeration can extend to the crista galli.
Development
Their origin is debated; they were initially thought to originate from displaced ethmoid air cells from the frontal recess, but a recent study suggests that they are actually diverticula from the frontal sinuses .
Practical points
These cells should be identified and reported on pre-functional endoscopic sinus surgery imaging studies as they can impinge and obstruct the frontal ostium.