Deck 1: Hepatobiliary, Urinary System, Pelvis

Where does the Superior Vena Cava drain from? List the 2 exceptions.

→ returns blood from all structures above the diaphragm

• Exception: lungs and heart

Where and how does the superior vena cava form and descend? FIX

• Forms on the right side, behind the costal cartilage of the 1st rib, at the junction of the brachiocephalic veins

• Descends posterior and to the right of the aorta

What are the 2 large vessels running down the posterior abdominal wall?

1. Abdominal aorta + its branches

2. Inferior vena cava + its tributaries

List the characteristics of the Liver. 

• 2nd largest organ in the body

• largest gland

• largest blood reservoir

• accounts for 2.5% of the adult body weight

• located in the upper right quadrant (RUQ)

All nutrients absorbed from the GI tract are sent to the ____ via the _____ for filtration. (Exception: _____)

All nutrients absorbed from the GI tract are sent to the liver via the portal venous system for filtration (Exception: fat)

What is the role of the Liver?

1. Produces and secretes bile

2. Stores: glycogen, minerals & fat-soluble vitamins (A, D, E, K)

Why is the liver’s movement with the diaphragm clinically important?

liver moves with the diaphragm → this mobility helps facilitate palpation during a physical exam

What are the external/visible lobes called?

Anatomical lobes

List the 2 main & 2 accessory lobes.

Main lobes: Right and left

Accessory lobes: Caudate and Quadrate

Which lobe has a “tail”? What this tail called?

Caudate has a tail called “caudate process”

What are the internal/functional lobes called? How many are there?

Segments - there’s 8

What are the Segments divided based on? What does this organization allow for?

→ Major subdivisions of the:

• hepatic artery

• portal vein

• hepatic ducts

*This organization facilitates surgical removal of individual diseased segments

List the 2 surfaces.

1. Diaphragmatic Surface

2. Visceral Surface

What is the diaphragmatic surface of the liver in contact with?

diaphragm

What is the bare area of the liver?

→ part of the liver not covered by peritoneum

• allows lymphatic drainage to easily pass to the diaphragm

List the 3 fissures found on the Visceral Surface. 

1. Left sagittal fissure

2. Right sagittal fissure

3. Porta hepatis (transverse fissure)

What structures hold the liver in place? List.

→ peritoneal reflections called ligaments:

1. Coronary and triangular ligaments

2. Falciform ligament

3. Round ligament

Where does the lesser omentum extend, and what does it enclose?

Lesser omentum extends from the liver to the lesser curvature of the stomach & the superior part of the duodenum

• encloses the portal triad

What does the portal triad consist of?

1) Proper hepatic artery (right & left hepatic arteries)

2) Hepatic portal vein

3) (Common) bile duct

Where does the Portal triad enter and exit?

enter and exit at porta hepatis (deep, transverse fissure on the underside of the liver)

What structures make up the hepatic biliary system?

• Right hepatic duct

• Left hepatic duct

• Common hepatic duct

Right & left hepatic duct join to make up the common hepatic duct

How does bile flow through the hepatic biliary system?

Bile flows either:

• directly to the duodenum

• indirectly via gallbladder through the extrahepatic biliary system

Where does the hepatic artery originate, and how is it divided? Draw the branching diagram.

Origin: branch of the celiac trunk

Hepatic artery divides into:

1. Common hepatic artery

2. Proper hepatic artery

How does blood enter and leave the liver?

Enters via the portal vein & proper hepatic artery

Leaves the liver through the inferior vena cava

What kind of blood supply does the liver have?

Liver has a dual blood supply from:

1. Portal vein (dominant) – brings 75–80% of blood to the liver

2. Proper hepatic artery – brings 20–25% of blood to the liver

What happens to the portal vein and proper hepatic artery (e.g., blood supplies to the liver) at the porta hepatis?

Portal vein & proper hepatic artery terminate by dividing into:

1. Right hepatic branches → supplies right lobe 

2. Left hepatic branches → supplies left lobe 

Describe the characteristics of the Portal Vein.

→ drains blood from the entire GI system in the abdominopelvic area via contributions from the splenic and superior mesenteric veins

• Short and wide

How does Venous drainage of the liver work?

Drains via the:

1. Right hepatic vein

2. Intermediate (middle) hepatic vein

3. Left hepatic veins

- these are intersegmental & open into the IVC within the liver

• Intersegmental = run b/w anatomical segments

• IVC helps hold the liver in place

What is the liver’s role in lymph production?

→ major lymph-producing organ

• 25% to 50% of the lymph entering the thoracic duct comes from the liver

What are portocaval (portal-systemic) anastomoses?

→ act as relief valves, allowing blood from the portal vein to bypass the liver and return to the heart

• not designed for high flow, so backup and complications occur

When blood flow through the liver is blocked, portal HTN occurs. What are the major complications of portal HTN in liver disease (e.g., cirrhosis)?

1. Esophageal Varicosities (Varices) - swollen veins in the esophagus

2. Hemorrhoids - swollen veins in the rectum or anus

3. Ascites - fluid in the abdomen

4. Caput Medussae - veins visible on the belly that look like snakes

   

What are the key features and functions of the gallbladder?

• Hollow, pear-shaped, intraperitoneal organ

• Fills by gravity; emptied by muscle contraction

• Function: Stores and concentrates bile

What is the function of the extrahepatic biliary system?

transports bile from the liver to the duodenum and/or the gallbladder

What does the Extrahepatic biliary system consist of?

1. Common hepatic duct

2. Cystic duct

3. Bile duct

Extrahepatic biliary system

What is the role of the cystic duct?

→ connects with the common hepatic duct and fills/drains the gallbladder

• spiral valve in the gallbladder neck keeps the cystic duct open, allowing bile to flow via gravity from the liver

Extrahepatic biliary system

How is the bile duct created?

via the union of the Common hepatic duct & Cystic duct

Extrahepatic biliary system

Describe the course and connection of the bile duct.

The bile duct:

1. Descends behind the 1st part of the duodenum & behind the pancreas head

2. Joins the main pancreatic duct at the hepatopancreatic ampulla (Ampulla of Vater)

What is the hepatopancreatic ampulla, and how is bile flow regulated?

→ hepatopancreatic ampulla opens into the duodenum as the “Major duodenal papilla”

• its surrounded by the hepatopancreatic sphincter (Sphincter of Oddi)

  • When this sphincter is closed, bile backs up into the cystic duct and enters the gallbladder

How is bile excreted?

• Hormonal or neural stimulation triggers bile release into extrahepatic bile ducts

  • Bile ducts carry bile from liver → gallbladder → duodenum

Where is bile produced, stored, and excreted?

Produced: Liver

Stored: Gallbladder (where it can solidify into stones)

Concentrated: Gallbladder

Excreted into: Lumen of the descending (2nd) part of the duodenum

What are the characteristics of the Pancreas?

• retroperitoneal accessory gland

• transversely crosses L1 and L2 vertebra

• Endocrine and exocrine gland

  • Exocrine secretion - enters the duodenum via the main and accessory pancreatic ducts → neutralize acidity

  • Endocrine secretions - enters the blood → produces hormones that regulate carb metabolism

What is the Transpyloric plane?

• intersects L1

• Found midway b/w the jugular notch of the sternum & upper border of the pubic symphysis

List the structures within the Transpyloric plane.

• Superior mesenteric artery, portal vein, renal arteries (origin)

• Gallbladder fundus

• Duodenojejunal flexure

• Left kidney hilum

• Spinal cord termination

• Pylorus (sometimes)

Name the parts of the Pancreas.

• Head

  • Uncinate process

• Neck

• Body

• Tail

Why can tumours spread so easily in the pancreas?

b/c they have no capsule so tumors spread easily

Where does the pancreatic duct begin, and how does it course through the pancreas?

pancreatic duct begins in the tail and runs through the pancreatic parenchyma (has the cells that produce digestive enzymes and hormone)

List the primary tissues of the Urinary System. Highlight the Retroperitoneal and Subperitoneal regions.

1. Suprarenal glands

2. Kidneys

3. Ureters

4. Bladder

5. Urethra

Differentiate the kidney placement.

Right kidney it positioned lower b/c the liver is on top

What are both kidneys capped by?

Suprarenal glands

What are the posterior relations of the kidneys?

Right kidney: Related to the 12th rib

Left kidney: Related to the 11th & 12th ribs

How does the appearance of the kidney differ in infants and adults?

• Infant kidney: lobulated surface (like an adult cow’s kidney).

• Adult kidney: smooth surface (about 11–12 cm long, 5–7 cm wide & 2.5–3 cm thick)

What structures are found at the hilum of the kidney?

• Renal Artery

• Renal Vein

• Renal Pelvis

The kidney is enclosed by a fibrous capsule with 2 layers.

• Outer layer: Protective and tough

• Inner layer: Stuck closely to the kidney surface

What does the Renal Medulla consist of?

1. Renal pyramids

2. Renal papillae

3. Renal columns

What does the Renal Sinus consist of?

1. Minor calyx

2. Major calyx

3. Renal pelvis

Describe the Renal Arteries.

→ originate directly from the aorta.

• branch into segmental arteries and smaller vessels within the kidney

• are “end arteries” — has no significant collateral circulation, so if one is blocked, that kidney segment dies

What is the function of the Renal veins? Outline venous drainage.

→ drain blood from kidneys into the inferior vena cava

Blood flows from interlobular veins → arcuate veins → interlobar veins → segmental veins → renal vein → IVC

What special vein connection does the left renal vein have?

During development (embryology), the left gonadal (testicular or ovarian) vein & left renal vein come from the same embryonic vein

• Left renal vein is longer

• Right renal vein is shorter

Describe renal lymphatic drainage.

• Lymphatics follow the renal veins

• Drain into the right and left lumbar (aortic) lymph nodes

List some examples of anatomical variances you’ll see in kidneys.

1. Renal cysts

2. Variations in vasculature

   

List the Renal Functions.

1) Excretory - removes extra or harmful water-soluble substances in urine — especially toxic nitrogen wastes like ammonia and urea

2) Regulatory - maintains stable fluid volume & ion composition

• regulates pH in conjunction with the lungs

3) Endocrine - produces and releases 3 hormones

What are the main features of the suprarenal (adrenal) glands?

• aka adrenal glands

• retroperitoneal

• sits on the superior pole of each kidney, in front of the crura of the diaphragm

• Shape 

  • Right gland - pyramidal shape

  • Left gland - crescent shape

• “2 in 1” glands – cortex and medulla have different functions and embryologic origins

  • Cortex: Mesoderm

  • Medulla: Neural crest cells

Function: neuroendocrine glands that respond to stress

What are the key features of suprarenal (adrenal) gland vasculature?

• Highly vascularized b/c hormones enter the venous bloodstream to reach targets

• Suprarenal veins mainly drain into the renal veins

  • sometimes drain directly into the IVC

What are the characteristics of the Ureters?

• Retroperitoneal organs

• firmly attached to the posterior abdominal wall

• pass through both the abdominal and pelvic regions

• Exit the kidney at the hilum and extend to the urinary bladder

• Urine moves through the ureters by peristalsis

What is the significance of ureter constrictions?

• Common sites for obstruction (e.g., kidney stones)

• BUT act as pseudovalves to slow urinary reflux

How is the 2nd constriction site of the ureter identified on imaging?

2nd constriction at the pelvic brim corresponds to the sacral promontory

What is an Intravenous Pyelogram (IVP) and how does it work?

• uses iodine-based dye that’s injected intravenously

• Dye is cleared by the kidneys, tracing the urinary pathway

• Hazard: Possible reaction to iodine-based dye

Why is ultrasonography used in urinary imaging?

• Safer alternative to IVP for detecting urinary obstructions

• can visualize kidneys and renal pelvis stones

What are the characteristics of the female urethra?

• Short & has no named parts

• Short length makes UTIs more common in females b/c bacteria can reach the bladder more easily

Where is the opening of the female urethra located?

In the vestibule of the vulva (space between labia minora), above the vaginal opening

What are the characteristics of the male urethra?

→ Dual purpose: transmits urine & semen

• 18-22cm long (b/c it has a dual purpose) — extending from internal urethral orifice at bladder to glands of penis

• Muscular conduit (uretha is part muscle to push fluid out actively)

List the 4 parts to the male urethra.

1. Preprostatic

2. Prostati

3. Membranous

4. Spongy

Parts of Male Urethra

What is the preprostatic urethra and what is its function?

Location: Neck of the bladder

Contains: Internal urethral orifice and internal urethral sphincter

Function:

• SNS innervation closes sphincter during ejaculation

• prevents backflow of semen into the bladder

Parts of Male Urethra

Where is the prostatic urethra located?

Surrounded by prostate tissue, which contributes secretions to semen

Parts of Male Urethra

What is the membranous urethra?

• Shortest section of the male urethra

• passes through the perineal membrane in the urogenital triangle

• surrounded by the external urethral sphincter which allows for voluntary urine control

Parts of Male Urethra

What is the spongy urethra?

• aka: penile urethra

• passes through the corpus spongiosum of the penis

• Ends at the glans penis (external urethral meatus)

What is important to know about abdominal dermatomes vs spinal levels?

• Ribs tilt downward anteriorly, so dermatomes don’t line up exactly with spinal levels

• Ex: T10 dermatome at the umbilicus corresponds to the L3–L4 intervertebral disc

What is referred pain and why does it occur?

→ Pain from one organ is perceived in a different location

• Causes:

  • shared neural pathways and ganglia

  • convergence of visceral & somatic afferent nerves in the spinal cord

  • only happens with organs that are supplied by autonomic (visceral) nerves

How is the peritoneum innervated and how does this affect pain?

Where is abdominal visceral pain from different gut regions referred?

→ reffered to the middle line regions

• Foregut: Epigastric region (upper midline)

• Midgut: Umbilical region (midline)

• Hindgut: Pubic/hypogastric region (lower midline)

How does appendicitis cause pain, and why does it change location?

Origin: Inflammation of the appendix

Pain pattern:

• Early: Periumbilical (visceral pain, T10 dermatome)

• Later: Right lower quadrant at McBurney’s point (parietal peritoneum involvement)

Mechanism:

• Visceral pain: Poorly localized, referred to midline (umbilicus)

• Parietal pain: Somatic nerves activated → sharp, localized pain at actual site

How does kidney stone pain present in the early stage and why? What dermatomes are involved?

→ Dull, aching pain in costovertebral angle (CVA) and flank

• Caused by kidney distension from ureteral obstruction

• Poorly localized b/c it’s visceral pain

Dermatomes: T10–L1

How does kidney stone pain present in the late stage and why? What dermatomes are involved?

→ Sharp, severe, colicky pain

• Radiates along ureter: flank → lower abdomen → groin

• Pain localizes as stone travels through ureter

Dermatomes: T11–L2

List the organs of the Pelvic Viscera.

• Bladder (Urinary)

• Ovary

• Uterine Tube

• Uterus

• Vagina

• Rectum

• Anal Canal

What do the ovaries produce and where does it go?

→ produce the ovum (egg) which travels through the uterine (fallopian) tube to the uterus

• At ovulation, the fimbria swell to move closer to the ovary to optimize capture of the ovum

List the main pouches in the female pelvis.

1. Rectouterine pouch

2. Vesicouterine Pouch

What are the key features and functions of the Uterus?

• Shape & size: Pear-shaped, ~7 cm long, 5 cm wide, 3 cm thick

• Functions:

  • Protects the embryo

  • Provides nutritional support

  • Removes waste produced by the embryo

List the main anatomical landmarks of the uterus.

• Fundus

• Body

• Uterine cavity

• Cervix

  • External orifice

  • Cervical canal

  • Internal orifice

How does pregnancy affect vision and why?

Caused by hormonal changes (estrogen, progesterone, relaxin) → leads to ↑ corneal thickness & curvature

• resolves 6–8 weeks postpartum

List the major ligaments that support pelvic organs and their functions.

• Broad ligament: sheet-like, provides major support to pelvic organs

• Ovarian ligament: stabilizes the ovary

• Suspensory ligament: supports the ovary and vessels

• Round ligament: restricts posterior movement of the uterus

What is the female inguinal canal and its significance?

• Passes the round ligament of the uterus (female analogue of spermatic cord)

• Anchors into the abdominal wall

• Clinical note: Smaller opening → less likely to develop hernia (ratio ~8:1 compared to males)

List the major organs of the Pelvic viscera of males.

• Testes

• Prostate & accessory glands

• Ductus deferens

How does sperm travel through the male urogenital system?

1. Testes

2. Ductus (Vas) deferens

3. Ejaculatory duct (formed by ductus deferens and seminal vesicle duct)

4. Prostatic urethra (within the prostate) + cowper’s glands

5. Membranous urethra (through pelvic floor)

6. Spongy/penile urethra

7. Navicular fossa

8. External urethral orifice

List the main pouches in the male pelvis.

Rectovesical pouch

Where is sperm produced? How does it travel from the testes?

Production: seminiferous tubules of the testes

1. Efferent ductules

2. Epididymis

3. Ductus deferens through abdominal wall

Note: Epididymis feels like an elongated lump; normal on self-exam

What is the ductus deferens and what was its former name?

→ Fibromuscular tube carrying sperm from testes to prostate

• Former name: Vas deferens

What is the largest accessory reproductive glands? Describe it

Prostate

• has a fibromuscular capsule

• surrounds the prostatic urethra

What is benign prostatic hyperplasia (BPH) and how is it treated?

→ age-related enlargement (hyperplasia) of the prostate

• constricts urethra → urinary retention + constant urge to pee

Treatment: Alpha-blockers (e.g., Flomax® / tamsulosin)

How does Alpha-blockers affect the eyes?

Causes Intraoperative Floppy Iris Syndrome (IFIS)

• reduces effective pupil dilation before and during cataract surgery

• e.g., cause the pupil to suddenly constrict during surgery

Note: Stopping medication before cataract surgery may not prevent IFIS

What is the Perineum?

shallow compartment inferior to the pelvic floor