Session 1 Flashcards
Label the diagram
Where is the origin of the testicular arteries?
Abdominal Aorta
Describe the venous and lymphatic drainage of the Right Testis, Left Testis, Scrotum and Prostate Gland
On the diagram label the:
Vas deferens
Spermatic cord
External spermatic fascia
Cremaster muscle/fascia
Internal spermatic fascia
Tunica vaginalis
From which layers of the anterior abdominal wall are the fascial coverings of the spermatic cord derived?
External Spermatic Fascia - External Oblique,
Creamsteric fascia - Internal Oblique,
Internal spermatic fascia -Transversalis Fascia
Shade the vas deferens in the picture
Complete the following table
Label the prostate and seminal vesicles on the diagram
Identify the different regions of the prostate
insert diagram
Label the diagram
What is the function of the male reproductive system?
Produce sperm which will travel through the reproductive system so that fertilisation can occur.
What is the purpose of the testis descending into the scrotum?
To allow spermatogenesis to occur at the optimum temperature which is slightly cooler than the core body temperature
Describe how blood supplies and leaves the testis
Blood supply is via the testicular artery which arises directly from the abdominal aorta. Venus drainage is via the pampiniform plexus which then goes on to form the right and left testicular vein. On the right, this drains directly into the inferior vena cava and on the left, it drains into the left renal vein before draining into the IVC.
What can happen if the venous drainage of the testis becomes obstructed?
It can cause a varicocoele
Where in the testis does spermatogenesis occur?
Seminiferous tubules
Describe the route to which sperm leaves the testis
Made in seminiferous tubules, leaves them via straight tubes into the rete testis (seminiferous tubules come together here) in mediastinum testis, which then drains into the head of the epididymis via the efferent ductules. Moves through epidiymis (head to body to tail) into the ductus/vas deferens out of the testicle.
What happens in the epidymis?
Sperm maturation
Sperm “learn to swim”, are concentrated and fluids are reabsorbed
Describe the layers of the testis from the seminiferous tubules
Seminiferous tubules surrounded by a capsule called the tunica albuginea (made of connective tissue). This capsule is then surrounded by tunica vaginalis which has two layers; A visceral layer (inside) and parietal layer (outside) which are separated by a cavity. Then wall of the scrotum.
What is a hydrocoele
Tunica vaginalis cavity fills with fluid
Describe the wall of the seminiferous tubule and its function
Walls of the seminiferous tubules are made from sertoli cells which trim away cytoplasm from the spermatocytes as they pass through them in order to make them more streamline/lighter. The sperm cells initially form from a germinal epithelium where the stem cells divide to give our sperm cells. Theres then a myoid cell layer (smooth muscle layer).
What are leydig cells and where are they found?
Found in the interstitial tissue between seminiferous tubules. They synthesis testosterone and are adapted to do this by having lots of smooth endoplasmic reticulum (involved in lipid metabolism), big neuclei and vacuoles (lipid storage)
Why is it believed that left testis sits lower then the right?
More venous congestion causing it to be lower as left testicle drains into left renal vein instead of straight into IVC
What is the benefit of the pampiniform plexus surrounding the testicular veins?
There is counter-current flow so heat exchange takes place. Arterial blood loses heat the venous blood. This helps to maintain a lower temperature in the testis to allow spermatogeneis to ccur at its optimum temperature - 35 degrees celsius
What is it called when a testicle get twisted? What are the risks and how does it happen?
Called testicular torsion. It is a surgical emergency. Spermatic cord gets twisted causing compression which leads to venous occlusion causing calpillary presure to rise which compresses arterial blood supply. This all leads to the blood supply to the testicle being cut off. This can result in necrosing of the testicle and can lead to infertility if not treated fast enough. Infertility can be caused by immune system now recognising the testicle as antigen within it now exposed and so it attacks the contralateral testicle so no healthy testicle left.
Why would someone be predisposed to testicular torsion and what can be done to help them?
Predisposition as a result of having Bell-clapper deformity. This can be overcome by attaching the testis to the wall of the scrotum to prevent twisting.
Can your testis cross over?
No as they are separated by the septum of the scrotum.
How is the spermatic cord formed?
The testis evaginate the abdominal wall as they are pulled through by the gubernaculum, forming the spermatic fascia that surrounds the testis and its vessels.
In detail describe/draw a cross section of the spermatic cord and its contents. Describe the origins of the structures too.
3 fascial layers, 3 arteris, 3 veins, 3 nerves and Vas deferens.
From deep to superficial: Internal Spermatic Fascia (derived from Transversalis Fascia) (fibrous), Cremasteric Fascia (derived from internal oblique) (contains muscle fibres which forms the cremaster muscle) and External Spermatic Fascia (derived from external oblique) (fibrous)
From deep to superficial (found between each layer of fascia): testicular artery, cremasteric artery and artery to vas
From deep to superficial: Testicular vein/pampiniform plexus, vein to the cremaster and vein to the vas
From deep to superficial: Nerve to cremaster / genital branch of the genitofemoral nerve (between internal and cremasteric fascia), sympathetics/nerve to the vas (mediate ejaculation), ilioinguinal nerve
Vas deferens, lymphatics and obliterated processus vaginalis found surrounded by the internal spermatic fascia.
Where is the cremaster muscle found and what is its function?
Found in the cremasteric fascia and regulalate height that the testes sit at in the scrotum. This is done to maintain optimum temperature. E.g on a cold day testes will be pulled higher to conserve heat
What is the processus vaginalis
Peritoneal connection between the testis and peritoneal cavity formed as testes descend.
Describe the important pelvic relations of the vas
Between vas and uereter. In the male the ureter passes under the vas . In the female the ureter passes under the uterine artery
Remember by thinking “ureter is water under the bridge”
What is the ejaculatory duct?
Where seminal vesicles join up with the vas deferens, runs through central zone of the prostate to enter urethra.
How can enlargement of the prostate affect the urethra and which region most commonly becomes enlarged?
Benign prosatic hyperplasia = prostate enlargement. Compresses the urethra, and transitional zone of the prostate which surrounds the urethra, is the area most commonly enlarged. This causes symptoms of lower urinary tract obstruction.
Which area of the prostate is most commonly affected by cancer? How does this relate to urinary flow and what does this mean for detection?
Peripheral zone so urinary flow may not affected however men with prostate cancer often have benign prostatic hperplasia which does affect urinary flow so both are often picked up at the same time.
Why is it more difficult to pass a catheter in males?
Men have a longer urethra and it has two bends. To do it the penis must be straightened and pointed downwards. There’s a risk of pushing the catheter into the prostate or into the wall of the urethra.
What are the functions of the penis?
Expulsion of urine via the urethra
Deposition of sperm in the female genital tract
Possibly removal of competitors’ sperm and attarction of mates
Describe the erectile tissue of the penis and how an erection is achieved and lost
Two corpus cavernosum and corpus spongiosum (surrounds urethra). erectile tissue surrounded by tunica albuginea which gives shape during erection. It has collagen fibres running in both transverse and longitudinal planes.
Vasodilatation in penile arteriles, and compression of veins results in erection.
Vasodilatation is initiated by parasympathetic stimulation.
Erection is terminated by vasoconstriction which is initated by sympathetic stimulation
Ejaculation is primarily orchestrated by the sympathetic system
THINK Point and Shoot
Point - Parasympathetic
Shoot - Sympathetic
Is penis anchored to bone?
Yes suspensory ligaments hold it to the pubic bone
corora cavernosa anchored to pelvis
How does the penis relate to the clitoris
They are homolgous structures. Both have corpus cavernosa anchored to the pelvis
Describe the blood supply and drainage of the penis. Why is this important when looking at diabetes?
Arterial blood from the internal iliac artery to the internal pudendal artery and into the penis. Blood leaves via the internal pudendal vein which runs into the internal iliac vein.
Microvascular disease and neuropothy can contribute to impotence
What is a fractured penis?
Penis is bent to such an extent that the tunica albuginea is ruptured resulting in haemorrhage of the corpus cavernosum. If not fixed quick enough a bend can persist.
Explain why trans-ilumination with a small bright torch can distinguish between a hyrdorcoele (or cystic mass) and a solid mass such as a tumour
Little if any light would penetrate the solid mass
What is the cremasteric reflex?
Stroking the skin on the medial side of the thigh evokes a reflex contraction of the cremaster which elevates the ipsilateral testicle. The reflex is mediated by the genitofemoral nerve (L1 and L2 nerve roots), although the afferent arc reflex may be via sensory fibres of the ilioinguinal nerve. The reflex is normally absent if the patient is suffering from testicular torsion.
Which portion of the prostate is felt in a rectal examination?
Peripheral lobe
