Paranasal Sinuses


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Paranasal Sinuses

 

air cavities in the cranial bones that communicate with the nasal cavity by means of narrow canals or fissures.

The maxillary sinus, or antrum of Highmore, is located in the maxillary bone; the opening connecting it to the nasal cavity is situated in the meatus nasi medius. The frontal sinus is located between the membranes of the orbital part and the squama frontalis; it communicates with the nasal cavity by way of the nasofrontal duct, which opens into the anterior part of the meatus nasi medius. The ethmoidal labyrinth consists of two to five or more air cells of varying size and shape. The anterior cells open into the meatus nasi medius, and the posterior cells into the meatus nasi superior. The sphenoidal, or wedge-shaped, sinus is located in the body of the sphenoid bone immediately behind the ethmoidal labyrinth; the anterior wall of each half of the sinus has openings that connect it to the nasal cavity.

The mucous membrane lining of the paranasal sinuses is similar in structure to that of the nasal cavity but is considerably thinner and relatively lacking in vessels and glands. The most common disturbances of the paranasal sinuses are caused by inflammations of their mucosa, or sinusitis, and by traumas.

References in periodicals archive ?
Allergy may produce a spectrum of changes in paranasal sinuses varying from mild mucosal thickening to complete opacification of the sinus (Fig.
Sinonasal polyposis is a typically extensive process with involvement of both the nasal cavity and the paranasal sinuses.
Hence, this study aims to identify the anatomical variations of the paranasal sinuses in the Omani population and their clinical significance.
The development of the paranasal sinuses begins as evaginations of the nasal mucous membranes during the second and fourth months of pregnancy.
Nonepithelial tumors of the nasal cavity, paranasal sinuses and nasopharynx; a clinicopathological study.
Imaging of paranasal sinuses plays an important role in diagnosing paranasal sinus diseases.
One study (5) found that renal primary tumours were most often responsible for secondary spread to the paranasal sinuses, and of these, the maxillary sinus is involved in 42%, the nasal cavity in 42% and the sphenoid sinus less frequently (6).
Orbital and paranasal sinuses metastases from prostate cancer are very rarely documented.
2 Early diagnosis of primary NHL of the nasal cavity and paranasal sinuses is difficult because this lesion develops in an anatomic space and expands toward the sinus, nasal cavity or nasopharynx, not usually causing symptoms in the early stages.
This was achieved due to an aggressive policy of computed tomography imaging of the paranasal sinususes in patients with febrile neutropenia, which frequently triggers the performance of paranasal sinuses biopsies.