Anatomy 25 Flashcards
Where do the adrenal glands lie?
Close to the upper pole of each kidney
Where does the right adrenal gland lie?
Behind the liver and inferior vena cava
Where does the left adrenal gland lie?
Behind the stomach and pancreas
Which 3 arteries supply the adrenal glands?
Superior adrenal artery
Middle adrenal artery
Inferior adrenal artery
What is the superior adrenal artery a branch of?
Inferior phrenic artery
What is the middle adrenal artery a branch of?
Abdominal aorta
What is the posterior adrenal artery a branch of?
Renal artery
What does the right adrenal vein drain directly into?
Inferior vena cava
What does the left adrenal vein drain first into?
Left renal vein
What does the left adrenal vein join?
Inferior vena cava
What is the adrenal gland composed of?
Cortex (outer part) and Medulla (inner part)
What does the cortex produce?
Steroid hormones including cortisol, aldosterone and testosterone
What does the medulla produce?
Adrenaline
What is Phaeochromocytoma?
Rare hormone-producing tumour of the adrenal medulla
What does secretion of excess adrenaline cause?
Symptoms and signs related to hyperactivity of the sympathetic nervous system, typically hypertension, tachycardia and excessive sweating
Where do the kidneys lie?
Outside the peritoneum so are called ‘extra-peritoneal’ structures, one on either side of the upper lumbar vertebrae
What is each kidney embedded in and what is it covered by?
Perinephric fat and this fatty layer is covered by renal fascia
What is on the medial border of the kidney?
Renal hilum, where the renal vessels, nerves, lymphatics and ureter enter or leave the kidney
What are the left and right arteries branches of?
Abdominal aorta
What do the left and right renal veins drain directly into?
Inferior vena cava
What is the internal aspect of the kidney composed of?
Cortex - outer part
Medulla - inner part arranged in pyramids
Calyces
What are the functional units of the kidneys (nephrons) responsible for?
Filtering blood
Reabsorbing water and solutes
Secreting and excreting waste products as urine
What structures are found in the cortex of the kidney?
Glomeruli
Glomerular capsules (Bowman’s capsule)
Proximal and distal tubules
Part of the collecting ducts
What structures are found in the renal pyramids?
Nephron loop (of henle)
Rest of the collecting ducts
What forms a major calyx?
Minor calyces merging with other minor calyces
What happens to urine from the collecting ducts?
Urine travels down the pyramid towards the renal papilla (the apex of the pyramid) where it enters a minor calyx
What do major calyces merge to form?
Renal pelvis
What is the renal pelvis continuous with?
Ureter
What is the function of the ureter?
Carry urine to the urinary bladder
What is the ureter?
Narrow tubes with muscular walls which transport urine by peristalsis
What do the ureter run anterior to?
Psoas major on the posterior abdominal wall and cross the pelvic brim to enter the pelvis
Where do the ureter enter the bladder?
On its inferomedial aspect
What are kidney stones often made from?
Calcium oxalate
What are some risk factors to developing kidney stones?
High urine calcium levels
Dehydration
Obesity
Certain medications
What can happen to smaller kidney stones?
Can pass into the ureter and out of the body via the bladder and urethra without causing any problems
What is the typical presentation of an obstructing kidney stone in the ureter?
Excruciating, pulsatile pain felt from ‘loin to groin
Why do kidney stones cause pain from ‘loin to groin’?
Pain fibres supplying the ureters originate from the T12 to L2 nerves, so pain is referred and felt in the T12-L2 dermatomes
what happens if the flow of urine from the kidney is obstructed?
The kidney will fill with urine and swell (hydronephrosis)
What can hydronephrosis lead to?
Infection
What are the 3 places where the ureter narrows?
- Pelvi-ureteric junction (PUJ) – between the renal pelvis and ureter.
- Pelvic brim - where the ureter runs over the pelvic brim, anterior to the iliac artery.
- Vesico-ureteric junction (VUJ) - where the ureter joins the bladder.
Where are kidney stones most likely to get stuck?
In the 3 places/regions where the ureter narrows
What are UTIs almost always caused by?
Bacteria (most commonly E. Coli) entering the urinary bladder via the urethra
Are UTIs more common in males or females and why?
Females as the female urethra is much shorter
What is infection of the urinary bladder called?
Cystitis
What are symptoms of cystitis?
Burning pain on passing urine and the sensation of having to pass urine much more frequently
What is the spread of infection from UTIs to the kidney called?
Pyelonephritis
What does Pyelonephritis require for treatment?
Intravenous antibiotics
What are symptoms of Pyelonephritis?
Fever
flank pain
Nausea and vomiting in addition to the symptoms of cystitis
What can caner of the kidneys be divided into?
3 main types, based on their histological origin
Where do Renal cell carcinomas (RCC) originate from?
Lining of the nephron
Where do Transitional cell carcinomas (TCC) originate from?
Epithelial lining inside the kidney
Where do Wilms’ tumours originate from?
Renal stem cells
What are the triad of symptoms of renal cancer?
Pain in the flank, a palpable mass in the abdomen and haematuria (blood in the urine)
What are kidneys encased in and what are their clinical importance?
Renal capsule, perinephric fat, renal fascia and paranephric fat, a renal cancer must grow very large and penetrate these layers before it is able to invade adjacent organs and structures
Why does a left-sided varicocele warrant investigation?
Left testicular vein drains into the left renal vein, which may be
compressed or obstructed by a renal tumour
What is the posterior abdominal wall?
Region behind the abdominal cavity and extends from the attachments of the diaphragm above to the pelvic brim below
What does the posterior abdominal wall consist of?
Lumbar spine together with the psoas and quadratus lumborum muscles
What structures run along the posterior abdominal wall?
Inferior vena cava
The aorta with its associated autonomic plexuses and lymph nodes
The sympathetic trunks on either side of the lumbar spine
What do the gonadal vessels supply?
The gonads (testes or ovaries)
Which spinal nerves form the lumbar plexus?
Lumbar spinal nerves L1-L4 (with a contribution from the T12
nerve) on the posterior abdominal wall
What does the lumbar plexus give rise to?
Several branches that innervate the skin and muscles of the abdominal wall and thigh
What do the Iliohypogastric and ilioinguinal nerves supply?
The anterior abdominal wall muscles and skin of the external genitalia
What does the Genitofemoral nerve supply?
The skin of the external genitalia
What does the Lateral femoral cutaneous nerve supply?
The skin over the lateral thigh
What does the Femoral nerve supply?
Supplies the muscles and skin of the anterior thigh and is often a target for nerve blocks to provide pain relief for lower limb fractures or surgery
What does the Obturator nerve supply?
Supplies the muscles and skin of the medial thigh
At which level does the thoracic aorta pierce the diaphragm?
Level of the T12 vertebra and descends through the abdomen as the abdominal aorta
Where does the thoracic aorta terminate?
Terminates by bifurcating into the left and right common iliac arteries at approximately the level of L4
What does the abdominal aorta give rise to?
Several unpaired and paired branches
Give examples of unpaired branches
Coeliac trunk
Superior mesenteric artery
Inferior mesenteric artery
Give examples of paired branches
Renal, adrenal, gonadal and lumbar arteries
(the latter supply the posterior abdominal wall)
What is the inferior vena cava formed by?
Union of the left and right common iliac veins at approximately the level of L5
Where do the veins which correspond to the paired arterial branches from the abdominal aorta drain into?
The inferior vena cava, although the left gonadal vein typically drains into the left renal vein
Which veins does the inferior vena cava receive?
Hepatic veins
What is an aneurysm?
The bulging of a blood vessel caused by a weak point in the blood vessel wall
What are some risk factors for the development of an abdominal aortic aneurysm (AAA)?
Smoking
Alcohol
Hypertension
Atherosclerosis
When are AAAs diagnosed?
If the diameter of the aorta is wider than 3cm
What happens if a AAA ruptures?
Significant intra-abdominal bleeding rapidly occurs, and mortality is high
What happens if a small AAA is found incidentally?
They are monitored to see if they increase in size, and treatment, including surgery or stenting, may be offered if they become too large
