A large channel of venous blood creating a “sinus” cavity bordered by the sphenoid bone and the temporal bone of the skull. The cavernous sinus is an important structure because of its location and its contents which include the third cranial (oculomotor) nerve, the fourth cranial (trochlear) nerve, parts 1 (the ophthalmic nerve) and 2 (the maxillary nerve) of the fifth cranial (trigeminal) nerve, and the sixth cranial (abducens) nerve.
A cavernous sinus thrombosis is a blood clot within the cavernous sinus. This clot causes the cavernous sinus syndrome.
The cavernous sinus syndrome is characterized by edema (swelling) of the eyelids and the conjunctivae of the eyes and paralysis of the cranial nerves which course through the cavernous sinus.
The orbital cavity is drained by paired veins called the superior and inferior ophthalmic veins. The superior ophthalmic vein arises at the inner angle of orbit and follows the course of ophthalmic artery into the cavernous sinus, a greatly dilated (widened) channel of venous blood. The inferior ophthalmic vein arises from a venous network at the forepart of orbit and divides into two branches one of which also ends in the cavernous sinus.
Inflammation of the lining membrane in any of the hollow areas (sinuses) of the skull around the nose. Sinusitis may be caused by anything that interferes with air flow into the sinuses and the drainage of mucous out of the sinuses. The sinus openings, called ostia, may be obstructed by swelling of the tissue lining […]
- Sinusitus headache
Headache that occurs in association with infection or inflammation of the paranasal sinuses, the air cavities within the passages of the nose. Common symptoms of sinus infection are headache, facial tenderness or pain, and fever. Other possible symptoms include cloudy, discolored nasal drainage, a feeling of nasal stuffiness, sore throat, and cough.
Abbreviation for small inhibitory RNA, a short sequence of RNA which can be used to silence gene expression.
A naturally occurring substance discovered in a soil sample from Easter Island. Sirolimus was initially thought to hold promise as an antifungal antibiotic but this idea was dropped when sirolimus was unexpectedly found to have immunosuppressive activity. The US Food and Drug Administration in 1999 approved the use of sirolimus as an immunosuppressant agent. But […]
- Situational syncope
The temporary loss of consciousness in a particular kind of situation. The situations that trigger this reaction are diverse, and include having blood drawn, straining while urinating or defecating, and coughing. It can also be due to the emotional stress, fear, or pain. When experiencing the trigger condition, the person often becomes pale and feels […]