Most superior sinus in the face
**Core Concept**
The paranasal sinuses are air-filled spaces around the nasal cavity that play a crucial role in reducing the weight of the skull and voice resonance. The **ethmoidal sinuses** are further divided into multiple small air cells.
**Why the Correct Answer is Right**
The **frontal sinus** is indeed the most superiorly located among the paranasal sinuses, positioned in the frontal bone of the skull. This location allows it to drain into the middle meatus of the nasal cavity via the frontonasal duct.
**Why Each Wrong Option is Incorrect**
**Option A:** The maxillary sinus, although one of the paranasal sinuses, is not the most superior.
**Option B:** The sphenoid sinus is located more posteriorly and inferiorly.
**Option D:** The ethmoidal sinuses, while superior in location, are not as high as the frontal sinus.
**Clinical Pearl / High-Yield Fact**
The frontal sinus is prone to **mucoceles** due to its dependent drainage pathway, which can lead to expansion and erosion of the surrounding bone.
**Correct Answer:** D. Frontal sinus