Anatomy Bladder, ureter, urethra, anus and perineum

Question 1

Name the two peritoneal pouches either side of the uterus.

Answer 1

Vesicouterine pouch (superior surface of bladder to to uterus)
Rectouterine pouch ( from posterior fornix of vagina to middle part of rectum)

Question 2

What is the pubvesicle ligament? What is the name of the equivalent in males?
What is the function of these ligaments?

Answer 2

The pubovesical ligament is a ligament that extends from the neck of the bladder to the inferior aspect of the pubis bones. In the female it is divided into two branches, the lateral pubovesical ligament and the medial pubovesical ligament.
In males it is called puboprostatic ligament.

To give support to the neck of the bladder and in urinary continence.

Question 3

What is the apex of the bladder attached to? What was its use in embryological development?

Answer 3

The apex of bladder is conntinous with the urachus (fibrous cord) forming the median umbilical ligament.

Closed upper end of the vesicourthral canal present in embryonic development.

Question 4

What type of muscle is detrusor muscle? How many layers? Describe their layout?
How does this change at the internal urethral orifice?

Answer 4

Smooth muscle.
3 Layers. Outer longitudinal layer, middle thin circular layer, inner longitudinal layer.
At the internal urethral orifice the middle circular layer become thick forming the sphincter vesicae.

Question 5

What is the trigone? How does the mucus membrane differ here form the rest of the bladder?

Answer 5

The trigone a smooth triangular region on the posterior internal wall of the bladder where the two ureteric orifices and the internal urethral orifice.

Elsewhere in the bladder the mucus membrane is attached loosely to the smooth muscle wall, forming fold allowing the bladder to stretch when distended. At the trigone the mucus membrane is firmly attached to the underlying muscle.

Question 6

Describe the innervation of the bladder.

Answer 6

Autonmic from pelvic plexus. Efferent Parasymathetic from the pelvic splanchnic nerves - motor fibres to detrusor muscle and inhibit sphincter vesicae.
Urethral sphincter (urogenital diaphragm) is supplied by pudendal nerve.

Question 7

Where is the urethra located in relation to the vagina.

Answer 7

Firmly attached to anterior wall of the vagina.

Question 8

What is the paraurethral duct, where does it open?

Answer 8

The paraurethral ducts (or Skene ducts) drain the paraurethral glands (collection of mucous secreting glands) of the female urethra. There is one duct, draining each gland, on each side, just proximal to the external urethral meatus.

Question 9

How does the smooth muscle layout differ from the bladder? Describe the 2 sphincters.

Answer 9

Urethra has internal longitudinal and external circular fibres. Circular fibres at proximal end form sphincter vesicae or the internal sphincter. The distal end is sphincter urethrae or external sphincter orifice.

Question 10

What type of epitheliums are found within the urethra

Answer 10

Continous with bladder, proximal transitional epithelium.

Distally non-keratinised stratified squamous nature.

Question 11

What is the blood supply of the urethra?

Where does it autonomic innervation come from?

Answer 11

Branches of internal pudendal artery

Pelvic plexus

Question 12

If rupture of the urethra occurs, what route does the urine take?

Answer 12

Urine escapes below the urogential diagphragm but deep to the superficial fascia. The only route it can take is via the areolar tissue of the mons pubis and anterior abdominal wall.

Question 13

How long are the ureters? What is there relation to the peritoneum.

Answer 13

Roughly 25cm. Retroperitoneal.

Question 14

From ureter to bladder: Describe the relation of the ureter to the following structures:

1) Psoas major
2) Genitofemoral nerve
3) Ovarian artery & vein
4) Bifurcation of the common iliac artery
5) The uterine artery + vessels (what route is the ureter taking at this level)
6) Ovary (level of internal iliac)
7) Lateral fornix of vagina

Answer 14

The ureter..

1) Descends anteriorly over psoas major
2) Passes anterior to gentiofemoral nerve
3) is posterior to the ovarian artery and vessels as the descend into the pelvis.
4) Passes anterior - common iliac
5) The ureter is posterior to the uterine vessels as it turns medially from the lateral wall of pelvis in the fascia of the pelvic floor (at levels of ischial spine) to reach the lateral aspect of the bladder.
6) At level of internal iliac artery, the utter is immediately posterior to the ovary.
7) Ureters 2cm lateral to supravaginal region of the cervix, as ureters pass forwards to reach bladder.

Question 15

What are the 3 histological layers of the ureter

Answer 15

1. Outer fibrous layer
2. Smooth muscle (upper 2 thirds, inner longitudinal and outer circular layer. Inner 1/3, additional outer longitudinal layer)
3. Transitional epithelium

Question 16

Ares of luminal narrowing of the ureter

Answer 16

Pelviureteric junction
Crossing pelvic brim (level of crossing bifurcation)
Vesicoureteric junction

Question 17

The ureters recieved blood from an anastomosis of several arteries. Name as many as you can.

Answer 17

Renal artery
Uterine/vaginal arteries
Gonadal artery
Middle rectal
Superior vesical (and inferior vesical in men) arteries

Question 18

What is the innervation levels of the ureter?

Answer 18

T11-L2

Question 19

Within the perineum, the urogenital region is described as superficial and deep.

What muscles are within the superficial region?

Answer 19

Bulbospongiosum
Right and left ischiocavernosus
Right and left transverse perineal muscles

Question 20

What muscles are within the deep region (deep perineal pouch) of the urogenital region?
Together what is the name of these muscles

Answer 20

Urethral sphincter
Deep transverse perineal muscles.

Urogential diaphragm. These two muscles are between 2 layers of fascia (superior fascia + inferior fascia (thicker layer)

Question 21

What is an alternative name for the thicker inferior fascia of the urogenital diaphragm?

Answer 21

Perineal membrane

Question 22

What is the name given to the space between in the inferior & superior fascia of the urogenital triangle?

Answer 22

Deep perineal pouch

Question 23

What are the contents of the deep perineal pouch?

Answer 23

Urethral sphincter
Deep transverse perineal muscles
Urethra & urethral glands.
Vessels and nerves

Question 24

What is the name of thickening in at the apex of the perineal membrame.

Answer 24

transverse perineal ligament.

Question 25

What passes between the transverse perineal ligament & arcuate pubic ligament (inferior aspect of pubic symphysis)

Answer 25

Deep dorsal vein of clitoris

Dorsal nerve of clitoris

Question 26

What is the blood supply to the perineum?

Answer 26

Internal pudendal artery

Question 27

As the internal pudendal artery hooks around the ischial spine, where in relation is the pudendal nerve.

Answer 27

The pudendal nerve is medial to the internal pudendal artery.

Question 28

The perineal artery (a branch of the internal pudenal artery alongside the inferior rectal artery) supplies which region?

Answer 28

Deep and superficial to the perineal membrane (skin & muscle)
Branches include posterior labial branches, deep artery of clitoris and dorsal artery of clitoris.

Question 29

What are the boundaries of the anal triangle?

Contents?

Answer 29

Anterior: Posterior aspect of perineal membrane
Lateral: Ischial tubersoities
Posterior: Sacrotuberous ligament
Contains anal canal and ischioanal fossa.

Question 30

What is the perineal body?

Answer 30

A fibromuscular node between the urogenital region and anal region where the muscles of the 2 regions form a functional unit. Fibres from levator also contribute.

Question 31

What are the boundaries of the sischioanal fossa?

Answer 31

Lateral: Ishium + obturator internus
Medial: Anal canal + lavator ani + external anal sphincter
posterior: Sacrotuberous ligament
Anterior: External urethral sphincter, deep transverse perineal muscle.

Question 32

What marks the anorectal junction

Answer 32

Attachment of puborectalis

Question 33

What are the anal columns

Answer 33

Mucous membranes that forms longitudinal folds, contain anal valves, anal sinuses and terminal branches of superior rectal vessels.

Question 34

What is the pectinate line

Answer 34

A line of inferior anal valves

Question 35

Describe the positioning of anal spincters

Answer 35

upper 3/4 - external and internal anal sphincter (circular muscle)
Lower 1/4 - external sphincter and subcutaneous part of external sphincter.

Question 36

What are the deep fibres of the external spincter merge with?

Answer 36

Puborectalis and muscles of the deep perineal pouch via the perineal body

Question 37

What are the superficial fibres of the external sphincter attached with

Answer 37

Anococcygeal ligament (fibrous muscular tissue separating the anus from the coccyx)

Question 38

What is a first degree tear

Answer 38

Injury to the perineal skin only

Question 39

What is a second degree tear

Answer 39

Injury to the perineal muscle but invoking anal sphincter

Question 40

What is a 3a degree tear

Answer 40

Less than 50% of the external anal sphincter torn

Question 41

What is a 3b degree tear

Answer 41

More than 50% of external anal sphincter

Question 42

What is a 3c degree tear

Answer 42

Both external and internal anal sphincter is torn

Question 43

What is a fourth degree tear?

Answer 43

Damage to both external and internal sphincter muscles and anal epithelium.