paranasal sinuses

Examples of paranasal sinuses in the following topics:

• Paranasal Sinuses

  • The paranasal sinuses (four, paired, air-filled spaces) surround the nasal cavity, and are located above and between the eyes, and behind the ethmoids.
  • Paranasal sinuses are a group of four, paired, air-filled spaces that surround the nasal cavity (maxillary sinuses), above the eyes (frontal sinuses), between the eyes (ethmoid sinuses), and behind the eyes (sphenoid sinuses).
  • The maxillary sinuses (also called the maxillary antrechea, the largest of the paranasal sinuses) are located under the orbits in the maxillary bones.
  • The paranasal sinuses form developmentally through excavation of bone by air-filled sacs (pneumatic diverticula) from the nasal cavity.
  • This image shows the position of the sinuses in the human skull.

• Nose and Paranasal Sinuses

  • The nose and paranasal sinuses form much of the upper respiratory tract, along with the pharynx.
  • The paranasal sinuses are a group of four, paired, air-filled spaces, lined with respiratory epithelium (ciliated columnar epithelium).
  • These are named according to the bones within which the sinuses lie: surrounding the nasal cavity (maxillary sinuses), above the eyes (frontal sinuses), between the eyes (ethmoid sinuses), and behind the ethmoid bone (sphenoid sinuses).
  • The functions of the sinuses are not fully understood, but there are many possible functions.
  • The most important function is the sinuses' role in draining mucus from the nasal cavity to the nasopharynx, which helps regulate pressure inside the nasal cavity.

• Sinusitis

  • Sinusitis, the inflammation of the paranasal sinuses, is a very common condition in the US with potentially dangerous complications.
  • Sinusitis is inflammation of the paranasal sinuses, which may be due to infection, allergy, or autoimmune issues.
  • Viral sinusitis typically lasts for 7 to 10 days, whereas bacterial sinusitis is more persistent.
  • Acute episodes of sinusitis can also result from fungal invasion.
  • Chronic sinusitis lasts longer than three months and can be caused by many different diseases that share chronic inflammation of the sinuses as a common symptom.

• Amoebic Meningoencephalitis

  • However, thus far the only route for Naegleria fowleri to enter the central nervous system is via deep insufflation of infected water as it attaches itself to the olfactory nerve, which is exposed only at the extreme vertical terminus of the paranasal sinuses.

• Structures Used in Voice Production

  • Resonance: The structures of the upper respiratory tract—particularly the soft palate of the mouth, the nasopharynx, and the paranasal sinuses—resonate and amplify the vibration of the vocal folds, making the sound louder and changing its tone.

• Ascending Aorta

  • The ascending aorta is the first portion of the aorta; it includes the aortic sinuses, the bulb of the aorta, and the sinotubular junction.
  • Just above the aortic valve are three small dilatations called the aortic sinuses, the two anterior sinuses give rise to the coronary arteries, the third posterior sinus does not usually give rise to any vessels and so is known as the non-coronary sinus.
  • The sinotubular junction is the point in the ascending aorta where the aortic sinuses end and the aorta becomes a tubular structure.

• Case study exercises

  • Researchers studying the effect of antibiotic treatment for acute sinusitis compared to symptomatic treatments randomly assigned 166 adults diagnosed with acute sinusitis to one of two groups: treatment or control.
  • (b) Based on your findings in part (a), which treatment appears to be more effective for sinusitis?
  • (c) Do the data provide convincing evidence that there is a difference in the improvement rates of sinusitis symptoms?

• Veins of the Head and Neck

  • The deep lying internal jugular vein receives blood from the dural venous sinuses found in the brain as well as the cerebral and cerebellar veins.
  • Dural sinuses are composed of dural mater lined with endothelium, making them distinct from both arteries, veins and capillaries.
  • The dural sinuses receive blood from the veins that drain the brain and skull.

• Short-Term Neural Control

  • Vascular baroreceptors are found primarily in sinuses (small cavities) within the aorta and carotid arteries.
  • The aortic sinuses are found in the walls of the ascending aorta just superior to the aortic valve, whereas the carotid sinuses are in the base of the internal carotid arteries.

• Carotid Sinus Syncope and Massage

  • Carotid sinus syncope sometimes accompanies convulsive seizures because of the intensity of the carotid sinus reflex when pressure builds in one or both carotid sinuses.