Ethmoid Labyrinth, Superior View

Description

Ethmoidal labyrinth dominates this superior view, with the paired lateral masses flanking the midline where the cribriform plate would sit to support the olfactory bulbs. Multiple ethmoidal air cells form a gridlike honeycomb across the roof of the labyrinth, separated by thin bony septa that create a repeating rectangular pattern. Anteriorly, the labyrinth narrows and tapers, while laterally the paper-thin lamina papyracea forms the medial orbital wall and defines the outer boundary of the ethmoidal complex. Fine cortical margins and internal trabeculation make the paranasal sinus architecture legible at a glance. Ethmoid anatomy is unforgiving in endoscopic sinus surgery, where a few millimeters separate the ethmoidal air cells from the orbit and anterior cranial fossa. Breach of the lamina papyracea can lead to orbital emphysema, medial rectus injury, or postoperative diplopia, while violation of the fovea ethmoidalis or cribriform region raises the stakes for cerebrospinal fluid leak and meningitis. The fixed superior perspective supports teaching of the ethmoidal lateral masses as a three-dimensional bony labyrinth, and the even lighting helps readers distinguish true septations from the outer cortical shell, a common point of confusion when correlating with coronal CT of the ethmoid sinuses. One tight space. Use this illustration in head and neck anatomy teaching, ENT surgical orientation materials, and radiology atlas pages that introduce ethmoidal air cell variants and the surgical relevance of the lamina papyracea as an orbital landmark. It also fits pathology content on ethmoiditis, mucoceles, and orbital complications of sinus disease. Anatomical accuracy verified by SciePro's Medical Advisory Board.