- Any demarcated portion of the body, either an area of the surface, a segment of the tissues, or a cavity. SEE ALSO: area, region, zone. SYN: spatium [TA]. [L. spatium, room, s.]- alveolar dead s. the difference between physiologic dead s. and anatomic dead s.; it represents that part of the physiologic dead s. resulting from ventilation of relatively underperfused or nonperfused alveoli; it differs specifically in being placed so as to fill and empty in parallel with functional alveoli, rather than being interposed in the conducting tubes between functional alveoli and the external environment.- anatomic dead s. the volume of the conducting airways from the external environment (at the nose and mouth) down to the level at which inspired gas exchanges oxygen and carbon dioxide with pulmonary capillary blood; formerly presumed to extend down to the beginning of alveolar epithelium in the respiratory bronchioles, but more recent evidence indicates that effective gas exchange extends some distance up the thicker-walled conducting airways because of rapid longitudinal mixing. Cf.:alveolar dead s., physiologic dead s.. SYN: anatomic airway.- apical s. the s. between the alveolar wall and the apex of the root of a tooth where an alveolar abscess usually has its origin.- Bogros s. SYN: retroinguinal s..- Böttcher s. SYN: endolymphatic sac.- capsular s. the slitlike s. between the visceral and parietal layers of the capsule of the renal corpuscle; it opens into the proximal tubule of the nephron at the neck of the tubule. SYN: Bowman s., filtration s..- cavernous spaces of corpora cavernosa [TA] the vascular spaces of the corpora cavernosa that, together with the intervening fibrous trabeculae, form the erectile tissue of the penis or clitoris. SYN: cavernae corporum cavernosorum [TA], caverns of corpora cavernosa, cavities of corpora cavernosa.- cavernous spaces of corporus spongiosum [TA] the vascular spaces forming the erectile tissue of the corpus spongiosum penis in the male and the bulb of the vestibule in the female. SYN: cavernae corporis spongiosi [TA], caverns of corpus spongiosum, cavities of corpus spongiosum.- central palmar s. the more medial of the central palmar spaces, bounded medially by the hypothenar compartment; related distally to the synovial tendon sheaths of digits 3 and 4 and proximally to the common flexor sheath. SYN: medial midpalmar s., middle palmar s..- corneal s. one of the stellate spaces between the lamellae of the cornea, each of which contains a cell or corneal corpuscle. SYN: lacuna (4).- Cotunnius s. SYN: endolymphatic sac.- (cranial) extradural s. [TA] s. between the cranial bones and the external periosteal layer of the dura; it becomes an actual s. only pathologically, as when as extra- or epidural hemorrhage occurs forming a hematoma.- dead s. 1. a cavity, potential or real, remaining after the closure of a wound that is not obliterated by the operative technique; 2. See anatomic dead s., physiologic dead s..- deep perineal s. the region immediately superior to the perineal membrane, occupied by the membranous part of the urethra, the bulbourethral gland (in the male), the deep transverse perineal and sphincter urethrae muscles, and the dorsal nerve and artery of the penis or clitoris. SYN: deep perineal pouch, spatium perinei profundum.- denture s. 1. that portion of the oral cavity which is, or may be, occupied by maxillary and/or mandibular denture(s); 2. the s. between the residual ridges which is available for dentures. SEE ALSO: interarch distance.- disk s. on radiographs of the spine, the radiolucent region between each pair of vertebral bodies.- Disse s. SYN: perisinusoidal s..- s. of Donders the s. between the dorsum of the tongue and the hard palate when the mandible is in rest position following the expiratory cycle of respiration.- endolymphatic s. [TA] endolymph-filled s. contained by the membranous labyrinth. SYN: spatium endolympha′ticum [TA].- epidural s. the s. between the walls of the vertebral canal and the dura mater of the spinal cord. SYN: extradural s. [TA], spatium extradurale [TA], spatium extradura′le, cavum epidurale, epidural cavity.- episcleral s. [TA] the s. between the fascial sheath of the eyeball and the sclera. SYN: spatium episclerale [TA], interfascial s., spatium interfasciale, spatium intervaginale bulbi oculi, Tenon s..- extraperitoneal s. [TA] loose areolar s. (potential only in many places) or plane immediately external to the peritoneum; in surgery, this plane enables dissection within the body wall but external to the peritoneum. SEE ALSO: retroperitoneal s.. SYN: spatium extraperitonea′le [TA].- freeway s. the s. between the occluding surfaces of the maxillary and mandibular teeth when the mandible is in physiologic resting position. SYN: interocclusal clearance, interocclusal distance (2), interocclusal gap, interocclusal rest s. (2).- intercostal s. [TA] an interval between the ribs, occupied by intercostal muscles, veins, arteries, and nerves. SYN: spatium intercostale [TA].- interfascial s. SYN: episcleral s..- interglobular s. one of a number of irregularly branched spaces near the periphery of the dentin of the crown of a tooth, through which pass the ramifications of the tubules; they are caused by failure of calcification of the dentin. SYN: interglobular s. of Owen, spatium interglobulare.- intermembrane s. the s. between the two membranes in a cell or organelle enclosed by a double biomembrane; E.G., the s. between the inner and outer membranes of the mitochondria; sometimes referred to as the external matrix.- interosseous metacarpal spaces [TA] the spaces between the metacarpal bones in the hand. SYN: spatia interossea metacarpi [TA].- interosseous metatarsal spaces [TA] the spaces between the metatarsal bones in the foot. SYN: spatia interossea metatarsi [TA].- interpleural s. SYN: mediastinum (2).- interproximal s. the s. between adjacent teeth in a dental arch; it is divided into the embrasure occlusal to the contact area, and the septal s. gingival to the contact area.- interseptovalvular s. the interval in the developing embryonic heart between the septum primum and the left valve of the sinus venosus.- intervaginal subarachnoid s. of optic nerve [TA] the spaces within the internal sheath of the optic nerve, between the arachnoidal and pial layers, filled with cerebrospinal fluid and continuous with the subarachnoid s.. SYN: spatium intervaginale subarachnoidale nervi optici [TA], intersheath spaces of optic nerve, Schwalbe spaces.- intervillous spaces the s.'s containing maternal blood, located between placental villi; they are lined with syncytiotrophoblast.- intraretinal s. the potential cleft between the pigmented and neural layers of the retina; it represents the cavity of the embryonic optic vesicle; retinal detachment occurs by the opening of this s..- spaces of iridocorneal angle [TA] irregularly shaped endothelium-lined spaces within the trabecular reticulum, through which the aqueous filters to reach the sinus venosus sclerae. SYN: spatia anguli iridocornealis [TA], ciliary canals, Fontana spaces.- Kretschmann s. a slight depression in the epitympanic recess below the superior recess of the tympanic membrane.- Kuhnt spaces shallow diverticula or recesses between the ciliary body and ciliary zonule that open into the posterior chamber of the eye.- lateral central palmar s. the more lateral (radial) of the central palmar spaces, bounded laterally by the thenar compartment; related distally to the synovial tendon sheath of the index finger and proximally to the common flexor sheath. SYN: lateral midpalmar s., thenar s..- lateral pharyngeal s. [TA] that part of the peripharyngeal s. located at the sides of the pharynx. SYN: spatium lateropharyngeum [TA], spatium pharyngeum laterale [TA].- leeway s. the difference between the combined mesiodistal widths of the deciduous cuspids and molars and their successors.- masticator s. a s. subtended by the superficial layer of the deep cervical fascia that splits into lateral and medial slings at the inferior border of the mandible to enclose the masseter muscle, part of the temporalis muscle, and the medial and pterygoid muscles before attaching to the zygomatic arch and base of the skull.- medullary s. the central cavity and the cellular intervals between the trabeculae of bone, filled with marrow.- muscular s. of retroinguinal compartment [TA] the lateral compartment beneath the inguinal (Poupart) ligament, for the passage of the iliopsoas muscle and femoral nerve; it is separated by the iliopectineal arch from the vascular lacuna. SYN: lacuna musculorum retroinguinalis, lacuna musculorum, muscular lacuna.- Nuel s. an interval in the spiral organ (of Corti) between the outer pillar cells on one side and the phalangeal cells and hair cells on the other.- paraglottic s. the s. on each side of the glottis bounded laterally by the perichondrium of the thyroid cartilage and the cricothyroid membrane and posteriorly by the mucous membrane of the pyriform sinus; anterosuperiorly it extends into the preepiglottic s.. It is an important route of transglottic and extralaryngeal spread of carcinoma of the larynx.- parapharyngeal s. [TA] SYN: pharyngomaxillary s.. SYN: spatium parapharyngeum.- Parona s. a s. between the pronator quadratus deep and the overlying flexor tendons of the forearm which is continuous through the carpal tunnel with the medial central palmar s..- parotid s. a deep hollow on the side of the face flanking the posterior aspect of the ramus of the mandible with its attached muscles that is occupied by the parotid gland; it is lined with fascial laminae (the parotid sheath) derived from the investing layer of deep cervical fascia; the structures bounding the s. collectively constitute the parotid bed. Surgeons operating in the area take advantage of the fact that the anteroposterior dimensions of the parotid s. increase with protrusion of the mandible. SYN: bed of parotid gland, parotid recess, recessus parotideus.- perichoroid s. SYN: perichoroidal s..- perichoroidal s. [TA] the interval between the choroid and the sclera filled by the loose meshes of the lamina fusca of sclera and the suprachoroid lamina. SYN: spatium perichoroideum [TA], perichoroid s..- perilymphatic s. [TA] s. between the bony and membranous portions of the labyrinth. SYN: spatium perilymphaticum [TA], cisterna perilymphatica.- perinuclear s. SYN: cisterna caryothecae.- peripharyngeal s. [TA] the s., filled with loose areolar tissue, around the pharynx; it is divided into two portions, parapharyngeal (lateral pharyngeal) spatium and retropharyngeal spatium. SYN: spatium peripharyngeum [TA].- perisinusoidal s. the potential extravascular s. between the liver sinusoids and liver parenchymal cells. SYN: Disse s..- perivitelline s. the s. between the vitelline membrane and the zona pellucida, appearing in an ovum immediately following fertilization.- personal s. a term used in the behavioral sciences to denote the physical area immediately surrounding an individual who is in proximity to one or more others, whether known or unknown, and which serves as a body buffer zone in such interpersonal transactions.- pharyngeal s. the area occupied by the pharynx (naso-, oro-, and laryngopharnynx). Not to be confused with the retropharyngeal s..- pharyngomaxillary s. the s. limited by the lateral wall of the pharynx, the cervical vertebrae, and the medial pterygoid muscle. SYN: parapharyngeal s. [TA].- physiologic dead s. (VD) unthe sum of anatomic and alveolar dead s.; the dead s. calculated when the carbon dioxide pressure in systemic arterial blood is used instead of that of alveolar gas in the Bohr equation; it is a virtual or apparent volume that takes into account the impairment of gas exchange because of uneven distributions of lung ventilation and perfusion.- plantar s. one of four areas between fascial layers in the foot, where pus may be confined when the foot is infected.- Poiseuille s. SYN: still layer.- preepiglottic s. the s. anterior to the epiglottis that is bounded anteriorly by the thyrohyoid membrane and the superior parts of the lamina of the thyroid cartilage, superiorly by the hyoepiglottic ligament and inferiorly by the thyroepiglottic ligament; laterally it extends into the paraglottic spaces. Carcinoma of the infrahyoid portion of the epiglottis often extends into the preepiglottic s..- pterygomandibular s. the area between the mandibular ramus and the pterygoid process of the sphenoid bone.- quadrangular s. musculotendinous formation providing passageway for the axillary nerve, posterior humeral circumflex artery, and accompanying veins as they run from the axilla to the superior posterior arm; as the neurovascular structures enter the formation anteriorly, it is bounded superiorly by the shoulder joint, medially by the lateral border of subscapularis, laterally by the surgical neck of the humerus, and inferiorly by the tendon of latissimus dorsi; where the vessels exit the formation posteriorly, it is bounded superiorly by the teres minor, medially by the long head of the triceps, laterally by the lateral head of the triceps and inferiorly by the teres major muscle or tendon; as they emerge, most of the neurovascular structures run on the deep surface of the deltoid muscle, which they supply. SYN: quadrilateral s..- quadrilateral s. SYN: quadrangular s..- Reinke s. a potential s. between the lamina propria and the external elastic lamina of the vocal fold. Edema in this s. produces hoarseness in chronic inflammation.- respiratory dead s. that part of the respiratory tract or of a single breath which fails to exchange oxygen and carbon dioxide with pulmonary capillary blood; a nonspecific term which fails to distinguish between anatomical dead s. and physiologic dead s..- retroadductor s. potential s. between the adductor pollicis and first dorsal interosseous muscles.- retroinguinal s. [TA] a triangular s. between the peritoneum and the transversalis fascia, at the lower angle of which is the inguinal ligament; it contains the lower portion of the external iliac artery. SYN: spatium retroinguinale [TA], Bogros s..- retroperitoneal s. [TA] the s. between the parietal peritoneum and the muscles and bones of the posterior abdominal wall. SYN: spatium retroperitoneale [TA], retroperitoneum.- retropharyngeal s. [TA] that part of the peripharyngeal spatium located posterior to the pharynx. SYN: spatium retropharyngeum [TA], Henke s., postpharyngeal s..- retropubic s. [TA] the area of loose connective tissue between the bladder with its related fascia and the pubis and anterior abdominal wall. SYN: spatium retropubicum [TA], cavum retzii, Retzius cavity, Retzius s..- retrosternal s. on lateral chest radiographs, the region dorsal to the sternum and ventral to the ascending aorta. SYN: anterior clear s..- retrozonular s. [TA] potential s. of the chamber of the eyeball immediately posterior to the zonule and anterior to the vitreous body. SYN: spatium retrozonulare [TA].- (spinal) epidural s. [TA] fat-filled s. immediately external to the dura mater ensheathing the spinal cord; contains the internal vertebral (epidural) venous plexus, and is the target site for epidural anesthesia. SYN: spatium peridurale.- subarachnoid s. [TA] the s. between the arachnoidea and pia mater, traversed by delicate fibrous trabeculae and filled with cerebrospinal fluid. Since the pia mater immediately adheres to the surface of the brain and spinal cord, the s. is greatly widened wherever the brain surface exhibits a deep depression ( e.g., between the cerebellum and medulla); such widenings are called cisternae. The large blood vessel s supplying the brain and spinal cord lie in the subarachnoid s.. SYN: spatium subarachnoideum [TA], cavum subarachnoideum, leptomeningeal s., subarachnoid cavity.- subchorial s. the part of the placenta adjacently beneath the chorionic plate; it joins with irregular channels to form the marginal lakes. SYN: subchorial lake.- subdural s. [TA] originally thought to be a narrow fluid-filled interval between the dural and arachnoid; now known to be an artificial s. created by the separation of the arachnoid from the dura as the result of trauma or some ongoing pathologic process; in the healthy state, the arachnoid is lightly attached to the dura (maintained in that position by the pressure of the cerebrospinal fluid) and a naturally occurring subdural s. is not present. SYN: spatium subdurale [TA], cavum subdurale, subdural cavity, subdural cleavage, subdural cleft.- subhepatic s. [TA] the part of the peritoneal cavity between the visceral surface of the liver and the transverse colon. SYN: recessus subhepaticus [TA], subhepatic recess.- subphrenic s. [TA] the recesses in the peritoneal cavity between the anterior part of the liver and the diaphragm, separated into right and left by the falciform ligament. SYN: recessus subphrenicus [TA], subphrenic recesses, suprahepatic spaces.- superficial perineal s. [TA] the superficial compartment of the perineum; the s. bounded superiorly by the perineal membrane (formerly the now obsolete inferior fascia of the urogenital diaphragm) and inferiorly by the superficial perineal (Colles) fascia; it contains the root structure of the penis or clitoris and associated musculature, plus the superficial transverse perineal muscle and, in the female only, the greater vestibular glands. SYN: spatium perinei superficiale [TA], Colles s., superficial perineal pouch.- suprasternal s. [TA] a narrow interval between the deep and superficial layers of the cervical fascia above the manubrium of the sternum through which pass the anterior jugular veins. SYN: spatium supraspinale [TA], Burns s..- Traube semilunar s. a crescentic s. about 12 cm wide, bounded medially by the left border of the sternum, above by an oblique line from the sixth costal cartilage to the lower border of the eighth or ninth rib in the midaxillary line and below by the costal margin; the percussion tone here is normally tympanitic, because of the underlying stomach, but is modified by pulmonary emphysema, a pleural effusion, or an enlarged spleen.- Trautmann triangular s. the area of the temporal bone bounded by the sigmoid sinus, the superior petrosal sinus, and a tangent to the posterior semicircular canal.- vascular s. of retroinguinal compartment [TA] the medial compartment beneath the inguinal ligament, for the passage to the femoral vessels; it is separated from the muscular lacuna by the iliopectineal arch. SYN: lacuna vasorum retroinguinalis [TA], lacuna vasorum, vascular lacuna.- Virchow-Robin s. a tunnel-like extension of the subarachnoid s. surrounding blood vessel s that pass into the brain or spinal cord from the subarachnoid s.; the lining of the channel is composed of pia and glial feet of astrocytes; a continuation of the s. around capillaries and nerve cells probably does not occur. SYN: His perivascular s..- Waldeyer s. SYN: Waldeyer sheath.- zonular spaces [TA] the spaces between the fibers of the ciliary zonule at the equator of the lens of the eye. SYN: spatia zonularia [TA], Petit canals.* * *single potential analysis of cavernous electrical activity
* * *space 'spās n1) a period of time also its duration2) a limited extent in one, two, or three dimensions3) a particular area or cavity within the body
* * *(spās) 1. a delimited area. 2. an actual or potential cavity of the body; called also spatium [TA]. 3. the expanse of the universe beyond the earth and its atmosphere.
For descriptions of specific anatomic structures not listed here, see under spatium.
Medical dictionary. 2011.