Relations
When exceptionally large they may extend into the roots of the pterygoid processes or great wings, and may invade the basilar part of the occipital bone.
Each sinus opens into the roof of the nasal cavity via apertures on the posterior wall of the sphenoethmoidal recess directly above the choana. The apertures are located high on the anterior walls of the sinuses themselves.
Because only thin shelves of bone separate the sphenoidal sinuses from the nasal cavities below and hypophyseal fossa above, the pituitary gland can be surgically approached through the roof of the nasal cavities by first passing through the anterioinferior aspect of the sphenoid bone and into the sinuses, followed by entry through the top of the sphenoid bone into the hypophyseal fossa.
If a fast-growing tumor erodes the floor of the sinus, the vidian nerve could be in danger. If the tumor spreads laterally, the cavernous sinus and all its constituent nerves could be in danger.
Read more about this topic: Sphenoidal Sinus
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“When any one of our relations was found to be a person of a very bad character, a troublesome guest, or one we desired to get rid of, upon his leaving my house I ever took care to lend him a riding-coat, or a pair of boots, or sometimes a horse of small value, and I always had the satisfaction of finding he never came back to return them.”
—Oliver Goldsmith (1728–1774)
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—Lillian Breslow Rubin (20th century)
“Words are but symbols for the relations of things to one another and to us; nowhere do they touch upon absolute truth.”
—Friedrich Nietzsche (1844–1900)