TBL20 - Posterior Abdominal Viscera Flashcards
Where are the ureters and suprarenal (adrenal) glands located within the abdominal cavity?
Like the kidneys, the ureters and suprarenal (aka adrenal) glands are retroperitoneal viscera
What is each kidney surrounded by and where does this tissue extend to? What encloses this tissue layer, where is it lacking, and where does it extend to?
1) Each kidney is surrounded by perinephric fat that extends into its hollow center, the renal sinus
2) The kidney and perinephric fat are enclosed, except inferiorly, by the fibrous renal fascia that is prolonged along the ureter as the periureteric fascia
What does the renal fascia enclose in addition to the kidney and what is it continuous with superiorly? What separates the adrenal glands and kidney? What is the primary fascial attachment of the adrenal gland to?
1) The renal fascia, which also encloses the adrenal glands, is continuous superiorly with the diaphragmatic fascia
2) A fascial septum separates the adrenal glands and kidneys
3) Thus, primary fascial attachment of the adrenal glands is to the diaphragmatic fascia not the renal fascia
Where do superior portions of the right and left kidneys lie respectively? When can vertical movement of the kidneys occur?
1) Due to the liver, superior portions of the right and left kidneys lie deep to the 12th and 11th ribs, respectively
2) During respiration and when changing from supine to erect positions, vertical movement of the kidneys can occur
Why is only the right kidney palpable in lean adults and when can the left kidney be palpated?
1) In lean adults, the inferior pole of the right kidney is palpable by bimanual examination as a firm, smooth, somewhat rounded mass that descends during inspiration. Palpation of the right kidney is possible because it is 1–2 cm inferior to the left one
2) The left kidney is usually not palpable unless it is enlarged or a retroperitoneal mass has displaced it inferiorly
Why can the kidneys descend when the body is erect? Do the adrenal glands descend with the kidneys?
1) Because the layers of renal fascia do not fuse firmly inferiorly to offer resistance, abnormally mobile kidneys may descend more than the normal 3 cm when the body is erect
2) When kidneys descend, the suprarenal glands remain in place because they lie in a separate fascial compartment and are firmly attached to the diaphragm
What is the renal pelvis and where does it lie? What do the ureters pass over to enter the pelvis?
1) The renal pelvis, the funnel-shaped superior end of ureter, lies posterior to the renal vessels at the hilum of the kidney
2) The long (25-30 cm) ureters pass over the bifurcation of the common iliac arteries to enter the pelvis
Cite three potential sites where kidney stones (aka calculi) can obstruct the ureters.
1) The ureters normally demonstrate relative constrictions in three places: (1) at the junction of the ureters and renal pelves, (2) where the ureters cross the brim of the pelvic inlet/over the external iliac arteries, and (3) during their passage through the wall of the urinary bladder
2) These constricted areas are potential sites of obstruction by ureteric stones (calculi)
Where do the renal arteries arise from? What are the adrenal glands supplied by?
1) The renal arteries arise from the abdominal aorta in close proximity to the SMA
2) The adrenal glands are supplied by small branches (ignore names) arising from the renal arteries and the aorta
Where does the left renal vein travel and terminate? Compare the drainage fields of the right and left renal veins.
1) The left renal vein traverses the acute angle between the aorta and SMA and like the right renal vein, terminates in the IVC
2) Right renal vein goes into IVC
3) Left renal vein goes into IVC, left gonadal vein drains into left renal vein, & communication of a ascending lumbar drains into the left renal vein
Where does lymph from the kidneys, ureters and adrenal glands drain into?
Lymph from the kidneys, ureters and adrenal glands drains into the lumbar lymph nodes positioned bilaterally along the abdominal aorta
Where do fibers of the lesser and least splanchnic nerves synapse in relation to the kidney? What forms plexuses that surround the renal arteries?
1) Fibers of the lesser and least splanchnic nerves synapse in the aorticorenal ganglion
2) Postsynaptic sympathetic fibers with branches of the vagus nerves form plexuses that surround the renal arteries
What does sympathetic-mediation contribute to the kidney blood flow? What synapses with modified sympathetic neurons in the medulla of the adrenal glands?
1) Sympathetic-mediated vasoconstriction contributes to the regulation of blood flow to the kidneys (role of the vagus nerve is uncertain)
2) Some fibers of the least splanchnic nerve directly enter the medulla of the adrenal glands to synapse with modified sympathetic neurons
Why are varicoceles (varicosities of the pampiniform venous plexus) more common on the left side?
Varicocele occurs predominantly on the left side, probably because the acute angle at which the right vein enters the IVC is more favorable to flow than the nearly 90° angle at which the left testicular vein enters the left renal vein, making it more susceptible to obstruction or reversal of flow
How is intermittent pain from nephroptosis relieved?
Symptoms of intermittent pain in the renal region, relieved by lying down, appear to result from traction on the renal vessels