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fossa[fos´ah] (pl. fos´sae) (L.)
a trench or channel; in anatomy, a hollow or depressed area.
amygdaloid fossa the depression in which the tonsil is lodged.
cerebral fossa any of the depressions on the floor of the cranial cavity.
condylar fossa (condyloid fossa) either of two pits on the lateral portion of the occipital bone.
coronoid fossa a depression in the humerus for the coronoid process of the ulna.
cranial fossa any one of the three hollows (anterior, middle, and posterior) in the base of the cranium for the lobes of the brain.
digastric fossa a depression on the inner surface of the mandible, giving attachment to the anterior belly of the digastric muscle.
1. one in the epigastric region.
2. urachal fossa.
ethmoid fossa the groove in the cribriform plate of the ethmoid bones, for the olfactory bulb.
glenoid fossa mandibular fossa.
hyaloid fossa a depression in the front of the vitreous body, lodging the lens.
hypophyseal fossa a depression in the sphenoid lodging the pituitary gland; called also pituitary fossa.
iliac fossa a concave area occupying much of the inner surface of the ala of the ilium, especially anteriorly; from it arises the iliac muscle.
incisive fossa a slight depression on the anterior surface of the maxilla above the incisor teeth.
infraclavicular fossa the triangular region of the chest just below the clavicle, between the deltoid and pectoralis major muscles.
infratemporal fossa an irregularly shaped cavity medial or deep to the zygomatic arch.
interpeduncular fossa a depression on the inferior surface of the midbrain, between the two cerebral peduncles, the floor of which is the posterior perforated substance.
ischiorectal fossa a potential space between the pelvic diaphragm and the skin below it; an anterior recess extends a variable distance.
mandibular fossa a depression in the inferior surface of the pars squamosa of the temporal bone at the base of the zygomatic process, in which the condyle of the mandible rests; called also glenoid fossa.
mastoid fossa a small triangular area between the posterior wall of the external acoustic meatus and the posterior root of the zygomatic process of the temporal bone.
nasal fossa the portion of the nasal cavity anterior to the middle meatus.
1. the lateral expansion of the urethra of the glans penis.
2. a depression on the internal pterygoid process of the sphenoid, giving attachment to the tensor veli palatini muscle.
3. vestibular fossa.
fossa ova´lis cor´dis a fossa in the right atrium of the heart; the remains of the fetal foramen ovale.
fossa ova´lis fe´moris the depression in the fascia lata that is bridged by the cribriform fascia and perforated by the great saphenous vein.
ovarian fossa a shallow pouch on the posterior surface of the broad ligament of the uterus in which the ovary is located.
paravesical fossa the fossa formed by the peritoneum on each side of the urinary bladder.
pituitary fossa hypophyseal fossa.
popliteal fossa the hollow at the posterior part of the knee.
subarcuate fossa a depression in the posterior inner surface of the pars petrosa of the temporal bone.
subpyramidal fossa a depression on the internal wall of the middle ear.
subsigmoid fossa a fossa between the mesentery of the sigmoid flexure and that of the descending colon.
supraspinous fossa a depression above the spine of the scapula.
temporal fossa an area on the side of the cranium bounded posteriorly and superiorly by the temporal lines, anteriorly by the frontal and zygomatic bones, and laterally by the zygomatic arch, lodging the temporal muscle.
tibiofemoral fossa a space between the articular surfaces of the tibia and femur mesial or lateral to the inferior pole of the patella.
urachal fossa one on the inner abdominal wall, between the urachus and the hypogastric artery.
vestibular fossa (fossa of vestibule of vagina) the vaginal vestibule between the vaginal orifice and the fourchette (frenulum of pudendal labia). Called also navicular fossa.
one of the pair of approximately equal chambers of the nasal cavity that are separated by the nasal septum and open externally through the nares and internally into the nasopharynx through the internal nares. Each fossa is divided into an olfactory region, consisting of the superior nasal concha and part of the septum, and a respiratory region, constituting the rest of the chamber. Overhanging the three meatuses of each fossa on the lateral wall are the corresponding superior, middle, and inferior nasal conchae. The superior meatus extends obliquely about halfway along the superior border of the middle concha. The middle meatus continues into the atrium and bulges on the lateral wall at the bulla ethmoidalis. The inferior meatus courses below and laterally to the inferior nasal concha and contains the opening of the nasolacrimal duct. The olfactory region is located in the most superior part of the fossa and contains olfactory cells, olfactory nerves, and olfactory hairs. The respiratory region is lined with mucous membrane, numerous glands, nerves, a plexus of dilated veins, and blood spaces. The plexus is easily irritated, causing the membrane to swell, blocking the meatuses and the openings of sinuses.
nasal fossa(1) Nasal cavity, see there.
(2) The space in the nasal cavity that is further subdivided by the projections of the nasal conchae.
nasal fossaSee Nasal cavity.
pl. fossae [L.] a trench or channel; a hollow or depressed area.
the nonarticular part of the acetabulum.
the depression in which the palatine tonsil is lodged in some species.
any of the depressions on the floor of the cranial cavity.
lateral cerebral fossa
see vallecula sylvii.
the cavity in which the glans clitoridis resides.
condylar fossa, condyloid fossa
either of depressions lateral to the occipital condyles.
a depression in the humerus for the coronoid process of the ulna. Called also radial fossa.
any one of the three hollows (rostral, middle and caudal) in the base of the cranium for the lobes of the brain.
the hollow in the cribriform plate of the ethmoid bones, for the olfactory bulb.
depression at the end of the stallion glans penis, housing the urethral process; it harbors smegma and potential pathogens.
a depression in the front of the vitreous body, lodging the lens.
hypophyseal fossa, hypophysial fossa
a depression in the sphenoid lodging the pituitary gland; called also pituitary fossa.
an irregularly shaped cavity medial or deep to the zygomatic arch.
the fossa between the cerebral peduncles.
a triangular depression between the crura cerebri.
a potential space between the pelvic diaphragm, the ischium and the skin.
lacrimal sac fossa
excavated from the lacrimal bone and housing the lacrimal sac.
the transverse groove on the dorsum of the bovine tongue between the torus and the tip.
a depression in the pars squamosa of the temporal bone at the base of the zygomatic process, in which the condyle of the mandible rests; called also glenoid fossa.
the right or left half of the nasal cavity.
see synovial fossa (below).
between the epicondylar crests at the distal end of the humerus; receives the anconeal process of the ulna.
fossa ovalis cordis
a fossa in the right atrium of the heart; the remains of the fetal foramen ovale.
a shallow depression on the surface of the mare's ovary. Called also ovulation fossa.
the hollow of the flank, bounded dorsally by the transverse processes of the lumbar vertebrae, cranially by the last rib and caudally by the muscles of the thigh.
see coronoid fossa (above).
floor of the fourth ventricle.
the depression between the condyles of the femur.
a depression cranial to the spine of the scapula.
depressed, cartilage-free islands in large articular cartilages; no function has been determined for them. Called also fossa nudatae.
an area on the side of the cranium bounded by the temporal line and the zygomatic arch, lodging the temporal muscle.
the deep fossa at the proximal end of the femur between the greater and lesser trochanters.
pertaining to the nose.
characterized by mild nasal discharge and hyperemia, occasionally severe rhinitis. See also pneumonyssuscaninum.
a chronic granulomatous lesion in the nasal cavity of the sheep, causing nasal obstruction and discharge, usually unilaterally.
in horses analogous to AL-amyloidosis in humans; can occur independently of a generalized disease, affecting nasal vestibule and anterior septum and turbinates, with sufficient nodular or diffuse deposits to obstruct the nasal passage.
nasal areae, nasal plane
the polygonal, raised, epidermal markings on the skin of the nasolabial plane of the dog. The pattern of marking is individual to each dog and can be used for identification, similar to the use of fingerprints in humans.
nasal bot fly
infestation causes sneezing and constant nasal discharge. The presence of the flies in the flock causes some insect worry. See also oestrusovis.
flow of the breath from the nostrils as distinct from the breath from the mouth.
nasal breath volume
as determined by holding the palms of the hands in front of the nostrils; diminution or cessation of flow are readily appreciated.
chronic nasal discharge without obvious physical cause. A specific problem of unknown etiology in rabbits, although Bordetella bronchiseptica is thought to be implicated. Manifested by sneezing, constant nasal and ocular discharge and matting of the fur on the insides of the forelimbs. Called also snuffles.
nasal cavity erectile tissue
erectile tissue present only in some patients; usually collapsed.
nasal cavity hemorrhage
nasal cavity obstruction
by mucosal inflammation, foreign body, neoplasm; detected by assessing the nasal breath flow.
nasal cavity olfactory region
located on ethmoturbinates, turbinates and nasal septum; covered by olfactory epithelium including sustentacular, basal and olfactory cells.
nasal cavity respiratory region
covers most of the cavities; covered by respiratory epithelium containing many, mainly serous, glands and carrying cilia.
see paranasal sinuses.
nasal cavity vestibular region
place of transition from skin to respiratory epithelium.
see Table 10.
reciprocal change in degree of congestion between nostrils; when the mucosa of one nasal cavity becomes congested the mucosal congestion of the opposite nasal cavity diminishes.
1. occurs as a congenital deviation of the maxilla and nasal septum and leads to malocclusion of the maxillary teeth.
2. in older animals can result from paranasal sinus cysts or sinonasal neoplasia.
may be unilateral or bilateral, serous, purulent, hemorrhagic, or contain food material.
see nasal diverticulum.
encapsulated nasal hematoma
persistent because of its size; blood is accumulated under respiratory mucosa so as to resemble a polyp. Like a polyp the hematoma obstructs the flow of breath through the nasal cavity.
enzootic nasal adenocarcinoma
of sheep and cattle may occur at a sufficiently high incidence to suggest an infectious cause. Usually unilateral in front of the ethmoid bone.
see facial fold1.
nasal foreign bodies
take the form of grass seeds or sticks poked up while the animal is scratching its muzzle in allergic rhinitis, especially in cattle. Cause sneezing, nasal discharge, inspiratory dyspnea, snoring noise and rubbing of the nose. Foreign bodies may be viewable or palpable.
see nasal fossa.
the caudal part of the nasal cavity, close to the ethmoid bone.
cause unilateral nasal obstruction; are usually the result of foreign body injury, rarely due to inept passage of a nasal tube or endoscope.
see epistaxis. Called also rhinorrhagia, nose bleed.
see nasal cavity.
see nasal acariasis (above).
nasal mucosal inflammation
causes respiratory stertor, mouth breathing, and small airstreams from the nostrils. It may be caused by a palpable foreign body.
smell of the nasal breath; may be necrotic, smell of ketones.
see nasal cavity.
see nasal plane.
see nasal polyp.
progressive nasal hematoma
see progressive nasal hematoma.
infection with the blood fluke schistosoma, which is largely asymptomatic but can cause dyspnea, snoring and profuse nasal discharge.
a vertical plate of bone and cartilage covered with mucous membrane that divides the cavity of the nose. See also septum.
see paranasal sinus.
cotton swab on a stick, passed up the nostril to obtain a sample of exudate and epithelial debris for microbiological or cellular examination.
see nasogastric tube.
see nasal conchae (above) and Table 10.
the part of the nasal cavity just inside the nostrils that is lined with skin.
flushing of the nasal cavity, usually with sterile saline, to recover cells or infectious agents for cytology or culture.