Anatomia dell'apparato urinario

anatomia


The kidneys are located in the lumbar fossa morphofunctional unit (lodges kidney). The loggia kidney is bordered anteriorly by the end of Toldt reinforced by the overlapping of the peritoneum, and posteriorly from Zuckerkandl. Together define a virtual space in the shape of inverted pyramid (with apex placed medially and below). In its entirety the band is defined as capsule Gerota and fits on top of the diaphragm. The kidney shaped oval "bean" and measures approximately 12 × 6 × 3 cm, respectively, in length and width and thickness. The surface is smooth, texture duroelastica. The weight is about 150 g. Each kidney has a convex front face, the rear flat, an outer margin convex and one concave medial interrupted from the hilum (vascular pedicle and the urinary tract and bordered by a front lip and rear). The kidney is covered by a capsule fibromuscular own but it is easily dissecabile from the underlying parenchyma. The cortex surrounds the medulla and is part of it with extensions (columns of Bertin). In turn, the spinal cord enters the cortical bone marrow infusion with these processes of Ferrein or medullary rays. The apex of the pyramid is the papilla in which, at the level of the area cribrosa, flow into the collecting ducts. The papillae are in varying numbers from 7 to 20, and are on average 12; have a height of 6-7 mm, a base of 8 mm and are marked by a collar. Each kidney is vascularized by branches of the renal artery that originates from abdominal aorta. A branch is usually back to the urinary tract (retropielico) and the others are front. Frequent abnormalities with the presence of vessels polar blocks. Inside parenchymal arteries divide into interlobar, to the base of the pyramids, where they constitute the arcuate arteries in cortical convexity. Originate from the convex side radial arteries which then become interlobular or glomerular. The concave surface of the arcuate arteries depart arteries straight true that you distribute to the pyramids. The venous circulation is collected from the veins that flow in the veins arcuate and interlobar later in the renal vein. The glasses that surround each papilla are at the origin of the excretory system and gather in three major collectors (upper, middle and lower), which in turn flow into the pelvis or pelvis or ampoule. The glass may have proportions and morphology varies but is usually triangular base at the top and bottom sides and apex in continuity with the ureter. It is a well-distensible and may have a capacity physiological (normal content) and a functional capacity (by overdistension). The ureter is a duct-mucosal muscle connected to the upper pelvis and bladder outlet. It has an approximate length of 25-30 cm and can be schematically divided into four portions: lumbar, iliac, pelvic, or intramural iuxtavescicale corresponding to the regions crossed. The caliber of the ureter is not uniform (from 2-3 mm to 5-6 mm) and has three physiological narrowing: the ureteropelvic junction, the junction with the iliac vessels, the intramural tract. The ureter is extraperitoneal throughout its course and sits on top of the psoas and down takes relationships with pyramidal muscles and internal shutter until the penetration into the bladder. Proceeding down the ureter to the right begins near the vena cava and left close to the aorta; then cross the spermatic vessels or ovarian vessels and colic. Lower down crosses the common iliac vessels and reach the promontory. Subsequently crosses the hypogastric arteries, umbilical and obturator. The woman takes a close relationship with the uterine artery and humans with the vas deferens. The bladder is a hollow organ with functions and median urinary reservoir and is located in the small pelvis. The shape and dimensions vary in relation to the degree of filling. The empty bladder
presents a triangular contour in the rear base and is flattened from top to bottom. As the urine is collected, the side walls diverge and stretch up to become convex to the upper part of the bladder that therefore becomes globular in shape (average diameter 12 cm). They are distinguished topographically a base or bottom, side walls, the front, the rear and the dome. The bladder is held fixed in its place by the peritoneum that adheres to the dome, as with ligaments and nearby organs and urethra. In the base of the bladder is distinguishable the trigone (triangular area apex antero-inferior whose base is recognizable by the presence of a saliency-mucosal muscle passing bridge between the two hosts ureteral, the bar interureterica and shallow (area retrotrigonale) . the hosts emerge ureteral mucosa with oblique from back to front and from outside inwards with bias cut: the antireflux mechanism vesicoureteral is ensured by the mechanisms of continence muscle its ureter and bladder wall itself, which is contracted on the intramural portion dell'uretere.Anteriormente bladder has relationship with the space of Retzius and posteriorly with the uterus and the vaginal fornix in women and with the rectum, the seminal vesicles and the prostate in men. the bladder is continuous below with the neck bladder and vesicoureteral junction. the male urethra is a duct-mucosal muscle length of about 18 cm which originates at the apex of the bladder neck and ends at the apex of the penis (external urethral meatus). It can be divided into segments according to a topographical criteria (pelvic urethra, perineal and penile) or systematically (prostatic, membranous, spongy or cavernous). While serving in the pelvic and perineal urethra is kept fixed from relations with neighboring organs (urethra sets), the penile portion is extremely mobile (urethra mobile). The course of the urethra is complex. In the stretch prostate goes down vertically and then to bend forward at the membranous portion with an angle of about 90 °. Immediately prior to the symphysis pubis again describes a 90 ° bend downwards. This curvature can however be reduced or absent in the process of penile erection or buttressing of the penis to the anterior abdominal wall. As regards the relations, penetrates the urethra in the prostate, forming with the longitudinal axis thereof an angle of 20 °. Abandoned the prostate is surrounded by a ring striated sphincter and runs close to the venous plexus pudendal and the pubic symphysis then engaging in trine urogenital and between the corpora cavernosa of the penis. The lumen of the urethra at rest is virtual and becomes cylindrical energized. In the rear wall of the prostatic urethra is a longitudinal ridge in elliptical boundary along approximately 1 cm, said seminal colliculus (the height of which emerges the prostatic utricle, represented by a diverticulum dead-end length of about 1 cm, and the learned ejaculatory prostate). In addition to the limit of the pit bulbar urethral lumen emerge in the outlets of the glands of Cowper. The female urethra is shorter course (3-4 cm) and flows into the vestibule of the vagina, behind the clitoris. Genital The prostate is a glandular organ located in the median and learn small pelvis between the base of the bladder and the urogenital trine, behind the symphysis pubis and front rectal ampulla. It has an irregular shape "chestnut" and reaches the maximum development postpubertal (20-25 years). It is contained in a fibrous crust (the prostate) through which contracted relations with the neighbors. The urethra, divided into a front portion and a rear portion divided in turn into a middle lobe, two side lobes and a rear portion. The consistency is hard-elastic and the surface is smooth. The seminal vesicles are two formations placed on the posterior-inferior wall of the bladder, above the rectum, prostate and laterally to the ducts deferens. The vesicle has a pear-shaped morphology and are distinguished a body and a neck: the latter flows into the vas deferens and becomes the ejaculatory duct which leads in turn to the level of the seminal colliculus, in the prostatic urethra. The body of the vesicle corresponds roughly to the trigone from a dimensional point of view(4-7cm × 1 cm). Section presents a series of sepimentazioni fibrous. Important are the relationships with the ducts deferens and the ureter: the latter indeed penetrates into the bladder between the top end of the seminal vesicle and bladder. The testicle is a body equal, ellipsoidal, located below the penis and contents into the scrotal sac. The left is usually lower than the right. The size varies depending on the subject and the texture is taut-elastic. Presents two faces (lateral and medial) and two poles (upper and lower). The medial surface, which faces the scrotal septum, has on the rear portion of the epididymis which continues on the posterior portion of the lateral face. Medially epididymis the testis enters into relation with the lower end of the spermatic duct. At this margin, is the hilum of the testis that gives passage to condottini efferent and blood vessels. The upper pole is covered by the head of the epididymis and has often fibrous appendix (Appendix of Morgagni). The lower pole gives attack on a plate fibromuscular (scrotal ligament) that connects to the bottom of the scrotal sac and is the residue of gubernaculum testis. The outer surface of the testis is covered by a lot serous double wall, the vaginal tunic own, which is derived from the duct embryologically peritoneo- vaginal. The virtual cavity bounded by two layers of the tunica propria contains a small amount of serous fluid and allows scrolling of the testis within the scrotum.