The ethmoid sinuses are a group of small air-filled spaces located within the ethmoid bone, which is situated between the eyes and forms part of the nasal cavity. These sinuses are responsible for producing mucus that helps to keep the nasal passages moist and trap pathogens and debris. They play a role in reducing the weight of the skull and contributing to voice resonance. There are typically 3 to 18 individual ethmoid air cells, which are divided into anterior, middle, and posterior groups. Inflammation or infection of the ethmoid sinuses can lead to conditions such as sinusitis, causing symptoms like nasal congestion, facial pain, and headaches. Proper drainage of these sinuses is essential for maintaining respiratory health.