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Related to Sinuses: Paranasal sinuses


(si'nus) plural.sinuses, sinus [L., sinus, curve, hollow]
1. A recess.
2. A cavity with a narrow opening.
3. An endothelia-lined, air-filled cavity within a bone. (When nonmedical people speak of 'sinuses', they are generally referring to this type of sinus, specifically, to the paranasal sinuses.)
4. An endothelia-lined channel for venous blood.
5. A channel leading to an abscess.

accessory nasal sinus

Paranasal sinus.

air sinus

Paranasal sinus.

anal sinus

Any of the saclike recesses on the inner lining of the anal canal between the anal columns.

aortic sinus

Inside the aorta, the pouch behind each of the three leaflets of the aortic valve. The right and left coronary arteries each originate from an orifice in an aortic sinus, leaving one aortic sinus (the noncoronary sinus) as a blind pouch. Synonym: sinus of Valsalva

basilar sinus

Transverse sinus (2).

carotid sinus

The small dilation at the base of the internal carotid artery with baroreceptors in its wall. These receptors respond to changes in arterial blood pressure, and their signals are carried to the hindbrain by the glossopharyngeal nerve (CN IX).

sinus cavernosus

Cavernous sinus.

cavernous sinus

A 1 cm wide dural sinus extending 2 cm along the medial wall of the base of the middle cranial fossa. The cavernous sinus empties into (a) the transverse sinus via the superior petrosal sinus, (b) the internal jugular vein via the inferior petrosal sinus, (c) the pterygoid plexus via emissary veins, and (d) the facial vein via the superior ophthalmic vein. The right and left cavernous sinuses are interconnected by the anterior and posterior intercavernous sinuses. Tributaries of the cavernous sinus include the superior ophthalmic, superficial middle cerebral, and inferior cerebral veins and the sphenoparietal sinus.
Synonym: sinus cavernosus

cerebral sinus

Dural sinus.

circular sinus

A set of four interconnected dural sinuses encircling the sella turcica and pituitary gland at the base of the brain. The four sinuses are the right and left cavernous sinuses and the anterior and posterior intercavernous sinuses.

coccygeal sinus

A sinus in the midline of the gluteal cleft just over the coccyx.

confluence of the sinuses

The dilated posterior end of the superior sagittal sinus in the skull. This dilation joins one of the transverse sinuses (usually the right), which drains the blood from the superior sagittal sinus toward the internal jugular vein. The other transverse sinus and the occipital sinus also connect to the confluence of the sinuses.)

coronary sinus

A large vein on the posterior surface of the heart; it runs in the atrioventricular groove between the left atrium and left ventricle. Most of the blood feeding the heart returns to the right atrium via the coronary sinus. Its direct tributaries include the small, middle, and great cardiac veins.

cranial sinus

Any of the large veins between the two layers of the cranial dura mater.

cranial venous sinus

Sinus (3).

dermal sinus

A congenital sinus tract connecting the surface of the body with the spinal canal.

draining sinus

An abnormal passageway leading from inside the body to the outside. This is usually due to an infectious process.

dural sinus

Any of several large endothelia-lined collecting channels into which veins of the brain and inner skull empty and which then empty into the internal jugular vein. These venous sinuses are found between the two layers (periosteal and meningeal) of the dura mater. Their walls have no muscle, and they have no valves to give direction to the blood flow. The venous sinuses in the skull include the superior sagittal, inferior sagittal, straight, transverse, and cavernous sinuses.
Synonym: cerebral sinus; dural venous sinus

dural venous sinus

Dural sinus.

ethmoid sinus

Any of the 3-18 paranasal sinuses on each side of the skull in and adjacent to the ethmoid bone. The ethmoid sinuses can be categorized as anterior, middle, or posterior, with each group usually draining into a different part of the nasal cavity. Ethmoid sinuses have very thin walls and are interconnected via openings in the septa between the sinuses.

frontal sinus

Either of a pair of paranasal sinuses in the frontal bones just above the orbits. These sinuses lie adjacent to each other in the midline, but are usually completely separated by a bony septum. Each frontal sinus drains into the ipsilateral nasal cavity through an opening in the lateral wall along the middle nasal passageway (i.e., middle nasal meatus).

genitourinary sinus

Urogenital sinus.

hair sinus

The sinus formed when hair is embedded in the skin and acts as a foreign body.

inferior longitudinal sinus

Inferior sagittal sinus.

inferior petrosal sinus

A dural sinus that drains the cavernous sinus posteriorly into the superior jugular bulb of the internal jugular vein.

inferior sagittal sinus

An unpaired midline dural sinus running along the lower, free margin of the falx cerebri (over the top of the corpus callosum). It drains blood from veins in the falx and from the medial surfaces of the hemispheres, and it empties, posteriorly, into the straight sinus.

intercavernous sinus

The anterior and the posterior intercavernous sinuses interconnect the right and left cavernous sinuses at the base of the brain. All sinuses are valveless; thus, the cavernous and intercavernous sinuses form a circle -- the circular sinus -- that enwraps the sella turcica.

lactiferous sinus

Immediately inside the tip of the nipple, the dilated end of any of the 15-20 lactiferous ducts, which convey milk from the mammary glands during lactation.

lateral sinus

Either of two large venous sinuses in the inner side of the skull passing near the mastoid antrum and emptying into the jugular vein.

lymph sinus

Endothelia-lined channels through which lymph flows inside lymph nodes. The walls of lymph sinuses are coated with T and B lymphocytes as well as phagocytic cells, all of which filter the passing lymph. Lymphocytes and macrophages move in and out of the lymph through the sinus walls.
Synonym: lymph channel

marginal sinus

1. Considered together, the many dilated veins or venous "lakes" that collect blood in the intervillous space of the placenta; the marginal sinus drains into the uterine veins.
2. A dural sinus along the inside of the rim of the foramen magnum; it drains into the vertebral venous plexus.
3. A blood-filled sinus in the marginal zone of the spleen. In the passage from the red pulp to the white pulp, some arterial blood flows along (and percolates through) the endothelia-lined walls of the marginal sinus before entering the arterial capillary beds of the white pulp.

mastoid sinus

An old term for the mastoid antrum.

maxillary sinus

Either of a pair of paranasal sinuses filling the bodies of the maxillary bones. The maxillary sinuses are large and pyramidal shaped, with average dimensions of 3.5 cm x 2.5 cm x 3.2 cm. The medial floor of the maxillary sinus is immediately above the roots of the first and second upper molars. Each maxillary sinus drains into the ipsilateral nasal cavity through an opening in the lateral wall of the hiatus semilunaris, under the middle nasal concha. Synonym: antrum of Highmore

occipital sinus

A slender dural sinus running in the posterior, i.e., attached, margin of the falx cerebelli. It begins near the foramen magnum, and it ascends along the midline of the occipital bone. The occipital sinus empties into the confluence of the sinuses.
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paranasal sinus

An air cavity in a facial bone, either the frontal, maxillary, sphenoid, or ethmoid bones; most paranasal sinuses occur in pairs. The paranasal sinuses are lined with ciliated epithelium that secretes mucus. The sinuses open into the lateral walls of the nasal cavities via small holes. Healthy paranasal sinuses are radiolucent. Synonym: accessory nasal sinus; air sinus; See: illustration

pericardial sinus

The oblique or the transverse pericardial sinus, which are spaces between the visceral and parietal layers of the serous pericardium. The oblique sinus runs along the posterior surface of the left atrium between the orifices of the right and the left pulmonary veins. The transverse sinus runs along the posterior surface of the base of the heart between the outflow vessels (the aorta and the pulmonary trunk) in front and the inflow vessels (the pulmonary veins) behind.

petrosal sinus

The superior or the inferior petrosal sinus.

pilonidal sinus

Pilonidal fistula.

pleural sinus

Any of the spaces in the pleural sac along the lower and inferior portions of the lung that the lung does not occupy.

sinus pocularis

A lacuna in the prostatic part of the urethra. Synonym: sinus prostaticus

sinus prostaticus

Sinus pocularis.

pulmonary sinus

Either of the pouches within the pulmonic trunk behind each of the three leaflets of the pulmonic valve.

sinus rectus

Straight sinus.

renal sinus

The indentation on the medial side of each kidney into which the hilum leads; the renal sinus is largely filled by the renal pelvis.

rhomboid sinus

The fourth cranial ventricle.

sagittal sinus

The superior or the inferior sagittal sinus.

sigmoid sinus

The continuation of the transverse sinus downward along the wall of the posterior cranial fossa to the jugular canal; there, the sigmoid sinus becomes the superior jugular bulb, the origin of the internal jugular vein.

sphenoid sinus

Either of a pair of paranasal sinuses in the sphenoid bone just above and behind the nasal cavity. The sphenoid sinuses are located adjacent to the optic chiasm, the pituitary gland, and the internal carotid arteries. Each sphenoid sinus drains through an opening in the sphenoethmoidal recess at the very top of the ipsilateral nasal cavity.

sphenoparietal sinus

A venous sinus uniting the cavernous sinus and a meningeal vein.

sinus of spleen

A large-capacity venous channel in the spleen.

straight sinus

An unpaired midline dural sinus where the falx cerebri and the tentorium cerebelli meet. The straight sinus is the posterior continuation of the inferior sagittal sinus. The straight sinus empties into the transverse sinus contralateral to the one joined by the superior sagittal sinus; nonetheless, the straight sinus often communicates, if only through a small channel, with the confluence of the sinuses.
Synonym: sinus rectus

superior petrosal sinus

A slender dural sinus that drains the cavernous sinus posteriorly into the transverse sinus.

superior sagittal sinus

A long unpaired midline channel through the superior margin of the falx cerebri. It begins in the front near the crista galli of the ethmoid bone, and it extends along the entire inner roof of the skull to the internal occipital protuberance in the back. Its posterior end, called the confluence of the sinuses, is dilated and usually joins the right transverse sinus; however, the other transverse sinus and the occipital sinus also communicate with the confluence of the sinuses. Tributaries of the superior sagittal sinus include ascending frontal cerebral veins, superior cerebral veins, diploic veins draining the skull bones, and a number of irregularly shaped venous lacunae. Numerous arachnoid granulations (sites of the return of water and filtrate from the cerebrospinal fluid) protrude into the superior sagittal sinus.

tarsal sinus

Sinus tarsi.

sinus tarsi

A space between the top of the calcaneus bone and the bottom of the tarsal bone.
Synonym: tarsal sinus

tentorial sinus

See: sinus rectus

terminal sinus

A vein encircling the vascular area of the blastoderm.

transverse sinus

A dural sinus in the lateral edge of the tentorium cerebelli along each lateral upper border of the posterior cranial fossa. One transverse sinus (usually the right) is a continuation of the superior sagittal sinus; the other transverse sinus (typically the smaller of the two) is the continuation of the inferior sagittal sinus, although both transverse sinuses usually have a connection near their origin, in the region of the confluence of sinuses. The transverse sinuses run anteriorly and turn downward to become the sigmoid sinuses at the front edges of the tentorium cerebelli; at this point, the transverse sinuses are joined by the superior petrosal sinuses. Tributaries of the transverse sinuses include inferior cerebral, inferior cerebellar, and diploic veins.

sinus tympani

A recess in the medial wall of the tympanic cavity beside the promontory and adjacent to the round window. The sinus tympani can be > 3 mm deep.

urogenital sinus

In the embryo, a space behind the urogenital membrane (a surface structure) and separated from the future rectum by the urorectal septum (an internal structure). The urachus and the mesonephric ducts, i.e., the Wolffian ducts, open into the urogenital sinus. The sinus will later give rise to major parts of the urinary bladder, urethra, vagina, and genitourinary tract glands.

uterine sinus

Any of the venous channels in the walls of the uterus during pregnancy.

uteroplacental sinus

Any of the slanting venous channels from the placenta serving to convey the maternal blood from the intervillous lacunae back into the uterine veins.

sinus of Valsalva

Aortic sinus.

sinus of venal canal

The portion of the right atrium of the heart posterior, and to the left of, the crista terminalis. The inferior and superior vena caval veins empty into it.

sinus venosus

In the embryo, the portion of the developing heart tube that leads into the cavities destined to form the atria and ventricles. The major embryonic veins — umbilical, vitelline, and common cardinal — all lead into the sinus venosum. Later, the sinus venosum will become the posterior smooth wall of the right atrium, including the openings from the coronary sinus and the venae cava.

venous sinus

A valveless irregularly shaped venous channel lined by endothelial cells. Large venous sinuses include the coronary sinus of the heart and the dural sinuses inside the skull; small venous sinuses are found inside certain tissues, such as the spleen.
Medical Dictionary, © 2009 Farlex and Partners


The nasal sinuses, air-filled cavities surrounding the eyes and nose, like the nose itself are lined with mucus-producing membranes. They provide cleansing to the nose, resonance to the voice, and structure to the face.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.

Patient discussion about Sinuses

Q. I have been having chronic pain in sinus area and behind my eyes, been to ENT who states it is not infection? I wake up with the pain and go to sleep in severe pain. Its all day and all night. Dr insists that its migraine related and allergy related. I have chronic postnasal drainage. It started 4 months ago when I moved into our new house. The pain makes me extremely fatigue and dizzy at times. I have been referred to the eye doctor, a headache specialist and an allergy specialist. Just recently I have had a CT scan and an MRI, as well as xrays of my sinus. Nothing other than a deviated septum and possible allergies from an ENT has been diagnosed. In the mean time I am waiting for the days to come when I can get into see these specialist. Anyone out there have any of the same symptoms?? Need help here. Soooooo sick of the pain.

A. i have chronic sinusitis and can really relate to what you describe. learned to live with the pain...but still, i use various ways to reduce inflammation in my sinuses, i heat the place up before going to sleep, try to avoid eating or drinking cold stuff.
another thing i do is i heat water (80c) then add a special oil i bought in a chinese medicine store , about 5 drops, and inhale the fumes. nettle tea can do wonders too.

More discussions about Sinuses
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References in periodicals archive ?
Importance of anatomical asymmetries of transverse sinuses: an MR venographic study.
The transverse sinuses, sigmoid sinuses, occipital sinus, superior and inferior sagittal sinuses and the major intracranial veins, including the veins of Trolard and Labbe were assessed using a schematic approach.
In order to combat sinus congestion and drainage concerns, people may try certain strategies that include flushing the sinuses and thinning the mucus.
This study included panoramic radiographs and CBCT scans of 104 maxillary sinuses in 52 individuals (26 females, 26 males), obtained for several dental causes which were available in the database of a private imaging center.
Although the sphenoid sinus does not transilluminate as brilliantly as the frontal or maxillary sinuses with a lighted guidewire, transillumination upon successful cannulation can be reliably noted in the mid and inferior portions of the sphenoid sinus when correct access has been obtained.
The absence of hyphae with the mucosa, bone and blood vessels characterizes noninvasive fungal sinusitis, while invasive fungal sinusitis is defined by the presence of hyphae within the mucosal and submucosal tissues, bone and blood vessels of the paranasal sinuses. Clinical symptoms of mycetoma are either absent or minimal.
The proportion of mucoceles located in the maxillary and ethmoid sinuses were both 30.6% ( n = 49).
Several studies have suggested that the frontal sinuses are slightly bigger in males than in females, and the presence of a metopic suture is associated with the absence of the frontal sinuses (BROWN et al., 1984; SCHULLER, 1943).
In a study of 31 patients, it took an average of 9.2 years before patients with pre-auricular sinuses sought medical care.2
A There is a new procedure for clearing out sinuses, with almost no side effects, called balloon angioplasty.
Sinusitis is a term used to describe infection or inflammation of the sinuses.
The Seasonal Sinus Support Aromatherapy Inhaler is formulated with organic, therapeutic essential oils, and can be used for sinuses, hay fever and allergies.