Anterior cells of ethmoid bone

The ethmoid bone contains a group of approximately 11 air-filled cavities called the anterior cells of ethmoid bone, also known as anterior ethmoidal air cells. These cells are an important part of the ethmoidal labyrinth, along with the middle and posterior ethmoidal air cells. They are strategically positioned on both sides of the midline of the nasal cavity, contributing to the complex network of air cells within the ethmoid bone. This organization highlights the ethmoid bone's role as a central component of the paranasal air sinuses.

The anatomical configuration of the ethmoidal air cells is meticulously designed. Laterally, these cells are enclosed by the orbital plate—a thin bony structure that separates them from the orbital cavity. Medially, the ethmoidal labyrinth's medial wall marks their boundary with the nasal cavity. The cells are organized into anterior, middle, and posterior clusters, each with its distinct location and drainage pathway. Notably, the anterior (and middle) air cells primarily drain into the middle meatus of the nasal cavity. Specifically, the anterior cells of ethmoid bone drain through the frontonasal duct, which connects directly to the ethmoidal infundibulum in the middle meatus.