Podcast
Questions and Answers
Which structure is NOT associated with the retroperitoneum?
Which structure is NOT associated with the retroperitoneum?
What determines the location of the right kidney in relation to the left kidney?
What determines the location of the right kidney in relation to the left kidney?
Which part of the kidney contains the nephrons?
Which part of the kidney contains the nephrons?
What is the correct sequence of hilar structures in the kidney from anterior to posterior?
What is the correct sequence of hilar structures in the kidney from anterior to posterior?
Signup and view all the answers
How many segmental branches supply the kidney?
How many segmental branches supply the kidney?
Signup and view all the answers
What is primarily produced by the adrenal cortex?
What is primarily produced by the adrenal cortex?
Signup and view all the answers
What anatomical feature is specifically associated with kidney stones?
What anatomical feature is specifically associated with kidney stones?
Signup and view all the answers
Which type of kidney stones accounts for the largest percentage of occurrences?
Which type of kidney stones accounts for the largest percentage of occurrences?
Signup and view all the answers
What is a possible consequence of having accessory renal arteries?
What is a possible consequence of having accessory renal arteries?
Signup and view all the answers
What is the main function associated with catecholamines produced by the adrenal medulla?
What is the main function associated with catecholamines produced by the adrenal medulla?
Signup and view all the answers
What anatomical relationship is evident between the kidneys and the floating ribs?
What anatomical relationship is evident between the kidneys and the floating ribs?
Signup and view all the answers
What is the main function of the renal papillae within the kidney?
What is the main function of the renal papillae within the kidney?
Signup and view all the answers
Which of the following best describes the vascular supply to the kidney?
Which of the following best describes the vascular supply to the kidney?
Signup and view all the answers
During the respiratory cycle, how much do the kidneys move vertically?
During the respiratory cycle, how much do the kidneys move vertically?
Signup and view all the answers
Which of the following structures is located in the retroperitoneum?
Which of the following structures is located in the retroperitoneum?
Signup and view all the answers
Which of the following nerves is NOT a part of the lumbar plexus?
Which of the following nerves is NOT a part of the lumbar plexus?
Signup and view all the answers
Which statement about the sympathetic and parasympathetic systems is accurate?
Which statement about the sympathetic and parasympathetic systems is accurate?
Signup and view all the answers
Which anatomical position is true regarding the largest nerve in the lumbar plexus?
Which anatomical position is true regarding the largest nerve in the lumbar plexus?
Signup and view all the answers
Which of the following is a characteristic of the sub-costal nerve?
Which of the following is a characteristic of the sub-costal nerve?
Signup and view all the answers
What is a notable feature of the splanchnic nerves within the autonomic nervous system?
What is a notable feature of the splanchnic nerves within the autonomic nervous system?
Signup and view all the answers
Which statement accurately distinguishes between the sympathetic and parasympathetic systems?
Which statement accurately distinguishes between the sympathetic and parasympathetic systems?
Signup and view all the answers
What is the primary role of the sympathetic nervous system in terms of body response?
What is the primary role of the sympathetic nervous system in terms of body response?
Signup and view all the answers
Which of the following accurately reflects the distribution of fibers in the autonomic nervous system?
Which of the following accurately reflects the distribution of fibers in the autonomic nervous system?
Signup and view all the answers
Which characteristic is true regarding the axons of preganglionic fibers in the autonomic systems?
Which characteristic is true regarding the axons of preganglionic fibers in the autonomic systems?
Signup and view all the answers
What distinguishes the neurotransmitter usage in the sympathetic and parasympathetic systems?
What distinguishes the neurotransmitter usage in the sympathetic and parasympathetic systems?
Signup and view all the answers
Study Notes
Retroperitoneum
- Structures associated with the retroperitoneum include organs (kidneys, ureters, suprarenal glands), major vessels (aorta, IVC), posterior wall muscles, diaphragm, lymphatic drainage, and nerves/nerve plexuses.
Kidneys
- Located against posterior abdominal wall, protected by floating ribs.
- Right kidney is lower than the left due to the liver.
- Hilum points medially, ureters descend at the level of the tips of vertebral transverse processes.
- Kidneys move up and down with each respiratory cycle (~ 1 inch).
- Flat organ, posterior and anterior.
- AP order of hilar structures: Renal vein, Renal artery, Ureter.
- Internal anatomy includes the cortex (nephrons), medulla (collecting ducts), pyramids, collecting system, and sinus.
Collecting system
- Renal papilla connects to the minor calyx, which joins to form major calyces.
- Major calyces drain into the renal pelvis, which connects to the ureter.
Suprarenal (Adrenal) Glands
- Differ in shape: Right is pyramidal, Left is crescent.
- Arterial supply: Superior, Medial, Inferior.
- Venous drainage: Only one vein each (defines the hilum).
- Cortex: Produces hormones that control sex, salt balance (aldosterone), and sugar balance (cortisol).
- Medulla: Produces catecholamines involved in fight-or-flight response.
Renal Arteries
- Variations due to kidney development: start in pelvis and ascend, re-establishing vascular supply along the process.
- If final arteries do not coalesce, they are known as accessory (segmental) renal arteries.
- Inferior accessory can compress ureter and lead to hydronephrosis.
Kidney Fusion Malformations
- During development, kidneys may fuse while ascending.
- The IMA stops the ascending of fused kidneys.
- Note anterior (vs. posterior) location of ureters.
- Types include sigmoid and horseshoe.
Horseshoe Kidney
- IMA sits between the two fused kidneys.
- Ureters pass anterior to the fused kidney mass.
Kidney Stones
- Three anatomical narrowing sites: Ureteropelvic junction, Crossing of iliac arteries, Ureterovesical junction. These are common locations for blockage.
- Most ERs use non-contrast CT scan for diagnosis, capable of detecting most stone types (except rare stones caused by protease inhibitors).
Types of Kidney Stones
- Calcium (82%)
- Uric Acid (7%)
- Struvite (7%)
- Cystine (1-3%)
Ureters
- Connect kidneys to the bladder.
- Descend at the level of the transverse processes of the lumbar vertebrae.
- Have considerable vascular supply.
- As the kidney ascends, the ureter becomes vascularized by branches from nearby vessels, which remain into adulthood.
Surgical Approaches to the Kidney
- Donor kidneys: Avoid going through the peritoneal cavity.
- Recipient kidneys: Placed in the iliac fossa (inside the peritoneal cavity).
Posterior Wall Vasculature
- Aorta: Unpaired vessel, lies anterior to vertebral column, on the left-hand side, terminates as common iliac arteries at the level of L4-L5.
- IVC: Post-renal IVC is on the right side, anterior to the vertebral column.
Paired Arteries of Aorta
- Inferior phrenic
- Middle suprarenal
- Renal
- Testicular/ovarian (gonadal)
- Lumbar (multiple)
- Common iliac
IVC Drainage of Gonadal Vein
- Right tributaries drain directly into the IVC.
- Left tributaries drain into the left renal vein.
- Note the relative positions of the left renal vein and SMA – "Anatomical nutcracker".
Anatomical Nutcracker
- The left renal vein can get compressed between the SMA and aorta, causing obstruction of blood flow.
Varicocele
- Dilation of the pampiniform plexus (network of veins in the scrotum).
- Seen as worm-like dilation, usually on the left side.
- More common in middle-aged and older males.
- Due to higher pressure on the venous system on the left - cumulative effect.
Diaphragm
- Fusion points can lead to defects which may result in herniations.
- Central tendon: Point of muscle convergence.
- Peripheral skeletal muscles: Vertebral or crural, Costal, Sternal
Diaphragm: Function and Innervation
- Function: Changes intra-abdominal and thoracic pressures, contraction descends for inspiration.
- Innervation:
- Phrenic nerve: Motor and sensory.
- Thoracic nerves: Sensory only.
Retroperitoneum: Organs and structures
-
The retroperitoneum is the space behind the peritoneal cavity. Contains important organs.
-
Organs of the retroperitoneum:
- Kidneys
- Ureters
- Adrenal glands
- Aorta
- Inferior vena cava (IVC)
- Posterior wall muscles
- Diaphragm
- Lymphatic drainage
-
Nerves and nerve plexuses also reside in the retroperitoneum.
Kidneys
- Located against the posterior abdominal wall.
- Right kidney is lower than left kidney due to the liver.
- Hilum of each kidney points medially.
- Ureters descend at the level of the tips of vertebral transverse processes.
- Kidneys move up and down with each respiratory cycle (around 1 inch).
Internal anatomy of the kidneys
- Cortex: Outermost layer, containing nephrons responsible for filtration.
- Medulla: Inner layer, containing collecting ducts.
- Pyramids: Cone-shaped structures in the medulla with bases at the corticomedullary junction and apexes (renal papillae) pointing towards the renal pelvis.
- Renal sinus: Space within the kidney containing the collecting system.
- Collecting system: Consists of minor calyces, major calyces, renal pelvis, which funnel urine towards the ureter.
Renal blood supply
-
Segmental arteries supply the kidney. Five branches:
- Superior
- Middle (2)
- Inferior
- Posterior
- These are end arteries, meaning blockage of one branch leads to tissue death.
Adrenal glands
- Shape: Right is pyramidal, left is crescent-shaped.
- Arterial supply: Superior, medial, and inferior adrenal arteries.
- Venous drainage: Single vein per gland.
-
Hormones:
- Cortex: Produces steroid hormones (androgens, estrogens), aldosterone (regulates salt balance), and cortisol (regulates sugar balance).
- Medulla: Produces catecholamines (adrenaline, noradrenaline), involved in the fight-or-flight response.
Ureter
- Connects kidney to urinary bladder.
- Descends at the level of the transverse processes of the lumbar vertebrae.
- Has significant vascular supply.
Vasculature of the posterior wall
-
Aorta: Unpaired vessel located anterior to the vertebral column, on the left side. Gives rise to paired arteries for different organs. Terminates as common iliac arteries at L4-L5 level.
-
Inferior vena cava (IVC): Located posterior to the aorta.
Paired arteries of the aorta
- Inferior phrenic arteries
- Middle suprarenal arteries
- Renal arteries
- Testicular/ovarian (gonadal) arteries
- Lumbar arteries (multiple)
- Common iliac arteries
Diaphragm
- Structure:
- Central tendon: Tough, central connective tissue sheet.
-
Peripheral skeletal muscles:
- Vertebral/crural: Attaches to vertebrae.
- Costal: Attaches to ribs.
- Sternal: Attaches to sternum.
- Function: Changes intra-abdominal and thoracic pressures. Contraction causes descent, aiding inspiration.
-
Innervation:
- Phrenic nerve: Provides motor and sensory innervation.
- Thoracic nerves: Provide sensory innervation only.
Kidney stones
-
Anatomical narrowing sites:
- Ureteropelvic junction.
- Crossing of the iliac arteries.
- Ureterovesical junction.
- These are common locations for kidney stones to cause obstruction.
Types of kidney stones
- Calcium stones: Most common (82%).
- Uric acid stones: 7% of cases.
- Struvite stones: 7% of cases.
- Cystine stones: 1-3% of cases.
Varicocele
- Dilation of the pampiniform plexus, a network of veins in the scrotum.
- Appears as a worm-like dilation in the upper scrotum.
- Common in middle-aged and older males.
- Usually affects the left side due to higher pressure on the left venous system.
Nerves of the Anterior Abdominal Wall
- The thoraco-abdominal nerves are continuations of the intercostal nerves (T7-T11)
- The subcostal nerve (T12) is located below the last rib
- The iliohypogastric and ilio-inguinal nerves are associated with the lumbar plexus (L1)
Lumbar Plexus
- The lumbar plexus innervates the lower limbs and the anterior abdominal wall
- The femoral nerve is the largest nerve and lies lateral to the psoas muscle
- The obturator nerve lies medial to the psoas muscle
Autonomic Nervous System
- The autonomic nervous system (ANS) maintains homeostasis in the body
- The sympathetic nervous system triggers the "fight or flight" response
- The parasympathetic nervous system can be considered "restorative" and usually counteracts the sympathetic system
Comparing Sympathetic and Parasympathetic Systems
- The sympathetic system utilizes norepinephrine for postganglionic neurotransmission (preganglionic uses acetylcholine)
- The parasympathetic system uses acetylcholine for both preganglionic and postganglionic neurotransmission
- Sympathetic fibers can be found throughout the body whereas parasympathetic fibers are restricted to the head, body cavities and some pelvic and abdominal regions
Sympathetic Nervous System Components
- The sympathetic nervous system is composed of a complex arrangement of neurons in the spinal cord and sympathetic ganglia
- Sympathetic ganglia are located outside of the spinal cord and connect to the central nervous system through preganglionic fibers
Structures Seen in the Image
- The left kidney and suprarenal gland are located on the posterior abdominal wall
- The left coeliac ganglion and coeliac plexus are at the root of the coeliac trunk
- The sympathetic trunk lies on the side of the lower thoracic vertebrae
Renal Anatomy
- The renal pelvis is located at the beginning of the ureter
- The pelvi-ureteric junction (PUJ) is a site of renal stone obstruction
Other Important Structures
- The iliohypogastric, ilio-inguinal, lateral cutaneous, and genitofemoral nerves all contribute to the innervation of the lower limbs and anterior abdominal wall
- The celiac ganglion is a major component of the sympathetic nervous system
- Renal cysts are benign fluid-filled sacs that can be seen on radiographic imaging
- An abdominal aortic aneurysm (AAA) is a localized enlargement of the abdominal aorta; rupture of an AAA can be life-threatening
Conclusion
The provided text describes the anatomy and function of the nerves and nerve plexus in the retroperitoneum. Special attention is paid to the sympathetic and parasympathetic nervous systems, their roles in homeostasis and their specific functions in the body. The text also highlights common abnormalities, such as renal cysts and abdominal aortic aneurysms.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz explores the structures associated with the retroperitoneum, including the kidneys, ureters, suprarenal glands, and major vessels. It also covers the internal anatomy of the kidneys and the collecting system, detailing their connections and functions. Test your understanding of these critical anatomical components and their relationships.
