Search results
Results From The WOW.Com Content Network
A sinus is a sac or cavity in any organ or tissue, or an abnormal cavity or passage. In common usage, "sinus" usually refers to the paranasal sinuses, which are air cavities in the cranial bones, especially those near the nose and connecting to it. Most individuals have four paired cavities located in the cranial bone or skull.
The paranasal sinuses are joined to the nasal cavity via small orifices called ostia. These become blocked easily by allergic inflammation, or by swelling in the nasal lining that occurs with a cold. If this happens, normal drainage of mucus within the sinuses is disrupted, and sinusitis may occur. Because the maxillary posterior teeth are ...
The sphenoid sinus is a paired paranasal sinus in the body of the sphenoid bone. It is one pair of the four paired paranasal sinuses. [1] The two sphenoid sinuses are separated from each other by a septum. Each sphenoid sinus communicates with the nasal cavity via the opening of sphenoidal sinus.
The frontal sinuses are located in the frontal bone; the sphenoidal sinuses in the sphenoid bone; the maxillary sinuses in the maxilla; and the ethmoidal sinuses in the ethmoid bone. [2] [13] A narrow opening called a sinus ostium from each of the paranasal sinuses allows drainage into the nasal cavity. The maxillary sinus is the largest of the ...
The mastoid antrum (tympanic antrum, antrum mastoideum, Valsalva's antrum) is an air space in the petrous portion of the temporal bone, communicating posteriorly with the mastoid cells and anteriorly with the epitympanic recess of the middle ear via the aditus to mastoid antrum (entrance to the mastoid antrum). These air spaces function as ...
Frontal sinus. Each frontal sinus is situated between the external and internal plates of the frontal bone. [1] [2] Their average measurements are as follows: height 28 mm, breadth 24 mm, depth 20 mm, creating a space of 6-7 ml. [3]
For example, very curvy ear canals, narrow ear canals, or surgical ears are more prone to earwax buildup. When wax builds up, it causes muffled hearing, tinnitus, or aural fullness (plugged-up ...
The inner ear (internal ear, auris interna) is the innermost part of the vertebrate ear. In vertebrates , the inner ear is mainly responsible for sound detection and balance. [ 1 ] In mammals , it consists of the bony labyrinth , a hollow cavity in the temporal bone of the skull with a system of passages comprising two main functional parts: [ 2 ]