APE 9: Anatomy of the Genito-Urinary System Flashcards
What is the female genital tract originally?
Mesodermal
What fuses together to develop the female genital tract and what does it create?
The para-mesonephric ducts which creates a genital septum across the pelvic cavity
What are the 3 components of the upper female genital tract?
Ovaries, uterine tube and uterus
What are the 3 components of the lower female genital tract?
Vuvla, cervix and vagina
What is the size and shape of a pear?
The uterus
What is the function of the uterus?
Gestation
What are the two main divisions of the uterus?
Fundus and body
What are the 3 tissue layers of the uterus?
Endometrium, myometrium and perimetrium
Inner to outer
Which part of the tissue layers if muscular?
Myometrium
What dilates the cervix?
The contractions of the myometrium
Where is the internal and external os?
Internal os= between the uterus and cervix
External os= between the cervix and vagina
What is the internal and external os?
A way for the cervix to communicate with the uterus and vagina, respectively
What begins at the internal os?
The uterine cavity
Why would clinicians be very familiar with the external os?
Swabs for cervical cancer and contraception
What is the difference between version and flexion?
Version= uterus lies more horizontally than usual, external os projects in one direction and fundus in the opposite direction Flexion= bend takes place at a level corresponding with the internal os, cervix is in one plane and body of uterus is in another
What are the two pouches anterior and posterior to the uterus?
Anterior= uterocervical pouch Posterior= rectouterine pouch
Which ligaments support the uterus?
Broad, round, ovarian, cardinal and uterosacral ligaments
What is the broad ligament?
Double layer of peritoneum attaching sides of uterus to pelvis
Why may the ovaries be very small in a cadaver?
Dehydration and menopause
What are the 2 ligaments of the ovary?
Ovarian and suspensory
What is the ovarian ligament?
Ligament that extends from the medial part of the ovaries to the fundus of the uterus
What is the suspensory ligament?
Fold of peritoneum extending from the mesovarium to the pelvic wall
What is the mesovarium?
The portion of the broad ligament of the uterus that suspends the ovaries
What is the mesosalpinx?
The portion of the broad ligament that stretches from the ovary to the level of the uterine tube
What is the blood supply of the uterus?
The uterine artery
From which artery does the uterine artery arise?
The internal iliac artery
Surgically, which important structure is related to the uterine artery?
Ureter
What are the 4 parts of the uterine tube?
Isthmus, ampulla, infundibulum and fimbreae
Where does fertilisation occur?
Ampulla of uterine tubes
What is the life-threatening condition associated with the uterine tube?
Ectopic pregnancy
What is the blood supply of the uterine tube?
Lateral half= ovarian arteries
Medial half= uterine arteries
Developmentally, how do the ovaries arise?
Retro-peritoneally on the posterior abdominal wall and then descends
Where does the ovarian blood supply come from and at which vertebral level?
Abdominal aorta, at L1/2
Where do the ovarian arteries drain to?
Right= inferior vena cava Left= left renal vein
Where do the lymphatics drain to and what is the significance of this?
Para-aortic lymph nodes
What is the vagina?
A fibro-muscular tube capable of expansion for the passage of the foetus
What are the vaginal fornices?
The anterior (front) and posterior (back) recesses into which the upper vagina is divided
What is anterior to the vagina?
Bladder and urethra
What is posterior to the vagina?
Rectum and anus
What is lateral to the vagina?
Ureters and uterine arteries
What is the practical significance of the posterior fornix?
Posterior fornix palpation exam
What does the vagina traverse?
A muscular diaphragm (pelvic floor)
What is the pelvic floor composed of?
The levator ani muscles
When are the levator ani muscles commonly damaged?
During childbirth
What is the external genitalia called?
The vulva
What arteries supply the vulva?
Pudendal arteries
Which never supplies the vulva?
Superficial inguinal lymph nodes
What does the male reproductive tract develop from?
The mesonephric ducts
What are the structures found in the internal male genitalia?
Testes, epididymis, urethra, prostate and ejaculatory duct
What are the structures found in the external male genitalia?
Scrotum and penis
What is the function of the testes?
Production of sperm and testosterone
Where do the testes descend from?
From the posterior abdominal wall to the scrotum
What radiates from the mediastinum?
Septa
What do the septa do?
Divides the testes into lobules
What do the lobules contain?
4-5 seminiferous tubules
What do the seminiferous tubules do?
Produce sperm
Why are the testes situated externally?
As they produce sperm and, to do this, the temperature of the testicles needs to be cooler than the inside of the body. This is why the scrotum is located outside of the body
Which artery supplies the testes?
Testicular artery
What is the clinical significance of the descent of the testes being arrested?
Causes cryptorchidism or undescended testicles
What does the testes descend down?
The inguinal canal
What is the epididymis?
It is a duct posterior to the testes, along which sperm passes to the vas deferens
What is the relationship between the testes and epididymis?
The head of the epididymis is attached to the seminiferous tubules of the testes
Which structure arises from the epididymis?
Vas deferens and ejaculatory duct
What is the vas deferens?
It is where sperm is stored prior to ejaculation
What is the course of the vas deferens?
It ascends to the bladder then comes back down to form the ampullae. The ampullae then joins the ducts of the seminal vesicles to form the ejaculatory ducts.
What is the vans deferens a component of?
The spermatic cord
Where is the spermatic cord formed?
At the opening of the inguinal canal
What is found in the spermatic cord?
Testicular artery, vein and nerve
What is the prostate gland?
A fibro-glandular structure in the shape of an inverted cone
Where is the prostate gland situated?
At the base of the bladder
What is the function of the prostate gland?
Secretes proteolytic enzymes into the semen, which break down clotting factors in the ejaculate, allowing the semen to remain in a fluid state, moving throughout the female RT for potential fertilisation
Which structure passes through the gland, from base to apex?
Urethra
What are the main zones of the prostate gland?
Central, transitional and peripheral
In which zone of the prostate gland does benign prostate hyperplasia (BPH) arise?
Transitional
In which zone pof the prostate gland does carcinoma arise?
Peripheral
What symptoms does BPH cause?
- Urgent/frequent need to urinate
- Difficulty starting urination
- Dribbling at end of urination
- Inability to completely empty the bladder
What are the seminal vesicles?
Male glands that produce 70% of semen
What is the position of the seminal vesicles with respect to the prostate gland?
Posterior to prostate
What is the relation of the ducts of the seminal vesicles with the ductus deferens?
The single excretory duct of each seminal vesicle is dorsal to the ductus deferens and it empties into the ampullae
What are the ejaculatory ducts?
A duct through which semen is ejaculated
Where do the ejaculatory ducts open?
They open into the urethra at the seminal colliculus
Where do they bulbo-urethral glands open?
Just below the prostate
What are the 3 components of the penis?
Root, body and glans
What are the 3 cylindrical structures that form the penis?
Paired corpus cavernosa and single corpus spongiosum
Which strcuture expands distally to form the glans penis?
Corpus spongiosum
Which of the 4 parts of the urethra pass through the penis?
Pre-prostatic, prostatic, membranous and spongy
Name the 3 pairs of arteries supplying the penis
Bulbourethral, deep penil and dorsal penile arteries
Which is the erectile tissue and what is the neurological control of this?
Corpus carvernosa, innervated by cavernous nerves in the peri-prostatic nerve plexus
What are the components of the urinary tract?
Kidneys, urinary bladder, urethra, and ureters
What is the position of the kidneys with respect to the abdominal cavity, thoracic cavity and vertebral column?
Lie retroperitoneally in the abdomen (behind the peritoneum), either side of the vertebral column
At which vertebral levels are the kidneys and what is the clinical significance of this?
T12-L3, can be used to observe any changes in size when interpreting radiographs
Which kidney is lower and why?
Right is lower than left due to liver sitting on right hand side, pushing it down
What is the space around the kidneys called and what is its clinical importance?
Peri-nephric space, if removed it feels like a floating kidney
What are the main features of a kidney?
Cortex, medulla and pyramids
What is the hilum of the kidney and which structures are found here?
It is where vessels pass
Contains renal vein, renal artery and renal pelvis (anterior to posterior)
What is the blood supply to the kidneys?
Renal artery
What is the function of ureters?
Transportation of urine from the kidney to the bladder
What is the position of the ureters with respect to the peritoneum?
It’s retro-peritoneal
Which arteries supply the ureters?
Upper third= renal
Middle= abdominal aorta
Lower= internal iliac
How do ureters enter the bladder?
In an oblique way
What is ureteric reflux?
When the valve between the ureters and bladder isn’t working properly so urine flows backwards into the ureters
At which point do the ureters narrow?
At the utero-pelvic joint
What does a blockage/narrowing of the ureters cause?
Hydronephrosis
From the end of the bed, how would you distinguish a patient with ureteric colic from a patient with appendicitis?
Patient with appendicitis would stay really still, ureteric colic patients would have flank pain
Where does ureteric pain radiate to?
Flank
Where would you look for a ureteric calculus (stones) on a plain radiograph?
L1- renal hilum, pelvic brim and ischial spines
What characteristic feature identifies the ureter, surgically?
It’s not pulsatile
Where is the ureter likely to be injured, surgically?
At the uterine artery
What is the difference between the bladder from when it’s empty to when it’s full?
Extra peritoneal when full but intra peritoneal when empty
What is the function of the bladder?
Collection, temporary storage and expulsion of urine
What is the sympathetic and parasympathetic innervation of the bladder and what does this cause?
Sympathetic= hypogastric nerve (T12-L2)- causes relaxation of detrusor muscle, promoting urine retention Parasympathetic= pelvic nerve (S2-S4)- causes contraction of detrusor muscle, stimulating micturition
What are the components of the bladder?
Apex, body, fundus and neck
Where does the apex point towards?
The pubic symphysis
Which structure arises from the apex band and what is its developmental significance?
Apex connects to the umbilicus by the medial umbilical ligament (a remnant of the urachus)
What does the neck do?
Joins the bladder and urethra
What is meant by the bladder trigone?
A triangular area located within the fundus of the bladder formed by the two ureteric orifices and the internal urethral orifice
Which structures enter and leave the trigone?
Opening from urethra and opening into ureters
What is the function of the internal and external sphincters?
Maintains continence (outflow of urine)
Which type of epithelium lines the bladder and why?
Transitional epithelium- as it can expand and contract
