| sinuses | Air filled cavities. Examples are the ethmoids, maxillary, frontal and sphenoid sinuses. (27 Sep 1997) |
|---|---|
| sinuses of dura mater | Endothelium-lined venous channels in the dura mater. Synonym: sinus durae matris, cerebral sinuses, cranial sinuses, sinuses of dura mater, venous sinuses. (05 Mar 2000) |
| syndromes of paranasal sinuses | <radiology> Gardner: osteomas, Kartagener: chronic infection, basal cell-nevoid, neurofibromatosis, Down (trisomy 21): hypoplastic frontal, sphenoid, with or without ethmoid, progeria: absent frontal sinuses; dwarf, immature, cleidocranial dysostosis: all sinuses absent/small (12 Dec 1998) |
| dural venous sinuses | Endothelium-lined venous channels in the dura mater. Synonym: sinus durae matris, cerebral sinuses, cranial sinuses, sinuses of dura mater, venous sinuses. (05 Mar 2000) |
| intercavernous sinuses | The anterior and posterior anastomoses between the cavernous sinus's, passing anterior and posterior to the hypophysis and forming, with the cavernous sinuses, the circular sinus. Synonym: sinus intercavernosi, Ridley's sinus. Jugular sinus Sinus jugularis, one of three enlargements of the jugular veins; the external jugular sinus is between the two sets of valves; the internal jugular sinus's are at the origin (superior bulb) and near the termination (inferior bulb). (05 Mar 2000) |
| aperture of mastoid antrum | The orifice leading from the epitympanic recess to the mastoid antrum. Synonym: aditus ad antrum. (05 Mar 2000) |
| mastoid | A bony process off the base of the skull that is composed of air cells. Inflammation of the mastoid is known as mastoiditis. (27 Sep 1997) |
| mastoid abscess | An abscess of the mastoid air cells. (05 Mar 2000) |
| mastoid air cells | Numerous small intercommunicating cavities in the mastoid process of the temporal bone that empty into the mastoid or tympanic antrum. Synonym: cellulae mastoideae, mastoid cells, mastoid sinuses. (05 Mar 2000) |
| mastoid angle of parietal bone | The posteroinferior point of the parietal bone. Synonym: angulus mastoideus ossis parietalis. (05 Mar 2000) |
| mastoid antrum | A cavity 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 aperture of the mastoid antrum. Synonym: antrum mastoideum, tympanic antrum, Valsalva's antrum. (05 Mar 2000) |
| mastoid artery | <anatomy, artery> Mastoid branch of occipital artery, passing through the mastoid foramen; distribution, mastoid air cells; anastomosis, middle meningeal artery. Synonym: arteriae occipitalis, ramus mastoideus arteriae occipitalis, mastoid branch of occipital artery. (05 Mar 2000) |
| mastoid bone | The nipple-like projection of the petrous part of the temporal bone. Synonym: processus mastoideus, mastoid bone, temporal apophysis. (05 Mar 2000) |
| mastoid border of occipital bone | The margin of the occipital squama that articulates with the temporal bone. Synonym: margo mastoideus squamae occipitalis, mastoid margin of occipital bone. (05 Mar 2000) |
| mastoid branches of posterior auricular artery | <anatomy, artery> Branches from stylomastoid branch of posterior auricular artery arising within the facial canal, distributed to the mastoid air cells. Synonym: rami mastoidei arteriae auricularis posterioris. (05 Mar 2000) |