#ethmoidsinuses

Answer: The paranasal sinuses are air-containing bony spaces around the nasal cavity. The mucous membrane of ciliated columnar epithelium lines the cavity.

Or, 

The paranasal sinuses are a group of air-filled cavities located within the bones of the skull around the nasal cavity. These sinuses include the frontal sinuses, ethmoid sinuses, sphenoid sinuses, and maxillary sinuses. They are lined with a mucous membrane and are connected to the nasal cavity through small openings called ostia.

02. What is the Classification of Para-Nasal Sinuses?

Answer: According to location the paranasal sinuses are classified as following pairs:-

i) Frontal

ii) Ethmoidal:- a) Anterior b) Middle c) Posterior

iii) Maxillary

iv) Sphenoidal

DETAILS:

The nasal sinuses also known as paranasal sinuses are classified based on their location within the skull. There are four main types of nasal sinuses:

i.    Frontal Sinuses:

· Location: Above the eyes and behind the forehead.

· Characteristics: Paired sinuses contributing to skull structure.

ii.    Maxillary Sinuses:

· Location: In the upper jaw below the eyes.

· Characteristics: Paired sinuses lightening the skull and aiding voice resonance.

iii.    Ethmoid Sinuses:

· Location: Between the eyes and behind the nose.

· Characteristics: Numerous small, labyrinthine spaces supporting nasal structure.

iv.    Sphenoid Sinuses:

· Location: At the base of the skull behind the eyes.

· Characteristics: Paired sinuses helping reduce skull weight and contributing to voice resonance.

These sinuses have interconnected openings draining into the nasal cavity. Classifying them is based on their specific locations and functions in supporting respiratory and cranial structures.

03. What are the Functions of Para-Nasal Sinuses?

Answer: The functions of paranasal sinuses are as the following: Such as-

i) The air contained within cavity adds humidity and temperature to the inspired air and serves as air-conditioning chamber.

ii) Act as resonating chambers for the production of sounds.

iii) Make the facial bones lighter and establish the adult contour of the face.

Or,

i.      Air Humidification and Filtration: Paranasal sinuses moisten and filter inhaled air, removing impurities before reaching the lungs.

ii.      Voice Resonance: Sinuses contribute to the resonance of the voice, enhancing vocal quality.

iii.      Skull Weight Reduction: Air-filled sinuses lighten the skull, promoting head movement and reducing strain on neck muscles.

iv.      Thermal Insulation: Sinuses help regulate air temperature, ensuring it is closer to body temperature as it enters the respiratory system.

v.      Protective Buffer: Sinuses provide a cushioning effect, potentially reducing the impact of facial trauma on the eyes and brain.