Where is the body of the penis suspended from?
pubic symphysis
What is the glans made from?
corpus spongiosum
Through which erectile tissue does the male urethra run?
corpus spongiosum
What are the 4 muscles located in the root of the penis? What is their action?
- Bulbospongiosus x2 – Found in the bulb. Contacts to empty spongy urethra of any residual semen or urine. Anterior fibres aid in maintaining erection by increasing pressure in the bulb of the penis.
- Ischiocavernosus x2 – Surrounds left and right crura. Contracts to force blood from cavernous spaces in the crura into the corpus cavernosa, helping to maintain an erection.
What are the 2 fascial coverings of the penis under the skin?
- Each mass of erectile tissue has 2 fascial coverings
- Superficial layer is the deep fascia of the penis, a continuation of deep perineal fascia.
- Under deep fascia is tunica albuginea
What is the suspensory ligament a condensation of? What does it connect?
condensation of deep fascia. Connects erectile bodies to pubic symphysis
What is the fundiform ligament a condensation of?
Condensation of abdominal subcutaneous tissue
How is the foreskin connected to the glans? What is the potential space between the glans and the foreskin (prepuce) called?
By the frenulum
Preputial Sac
What does the internal pudendal artery arise from?
internal iliac
Describe the venous drainage of the penis
Venous blood drained via deep dorsal vein of penis (empties into prostatic venous plexus) and superficial dorsal veins (drains skin and cutaneous tissue)
What is the innervation of the penis? Which spinal nerve roots? What nerve supplies sensory, sympathetic and PS innervation?
- Supplied by S2-S4
- Sensory and sympathetic innervation supplied by pudendal nerve
- PS innervation is from prostatic nerve plexus.
Is erection governed by sympathetic or PS? What about ejaculation?
Point and Shoot – PS is erection, Sympathetic is ejaculation
What is hypospadias? What are the different types of Hypospadias?
A congenital condition in which patients are born with the opening to their urethra on the ventral aspect of the penis
Subcoronal, midshaft, penoscrotal
What is phimosis? What are the symptoms and why?
Prepuce fits tightly over glans and cannot be retracted. Causes irritation when smegma accumulates in preputial sac.
What is paraphimosis? What is the result?
Rectraction of prepuce constricts neck of glans, interfering with venous and lymphatic drainage. Can cause glans to enlarge to extent that prepuce cannot be drawn over it.
What is peyronie’s disease? What are the symptoms?
- Abnormal curvature of shaft of penis caused by build up of scar tissue
- Pain on erection
What is the common cause behind ED?
Vascular aetiology, e.g. hypertension
What is priapism? What can happen?
- Erection for more than 4 hours
- Caused by blood being trapped in erectile bodies
- Can lead to scarring and ED.
What is the innervation of the testes?
Testicular plexus
What is the arterial supply to the testes and epididymis?
Testicular arteries, arising from Abd Aorta
What is the venous drainage of the testicles? How do the right and left testes differ? How does the venous drainage cool the blood?
- Venous drainage via testicular veins. Formed from pampiniform plexus in scrotum.
- Left testicular vein drains into left renal vein
- Right testicular vein drains directly into IVC
- Pampiniform plexus surrounds testicular arteries and cools the blood down by 2-8 deg C.
What lymphatic nodes drain the testes? Where are they located?
lumbar and preaortic nodes located at L1
What is hydrocoele?
Serous fluid within tunica vaginalis.
What is haematocoele? How can you distinguish from hydrocoele?
collection of blood in tunica vaginalis. Distinguishable from hydrocele by transillumintion, light cannot pass through dense blood.
What is varicocoele? Why is the left more commonly affected?
dilation of veins. Left testicle more commonly affected due to drainage into smaller left renal vein at a perpendicular angle.
What is the function of the dartos muscle?
Acts to regulate temperature of scrotum by wrinkling the skin – decreases SA and reduces heat loss
What arteries feed the scrotum?
anterior and posterior scrotal arteries arising from external and internal pudendal arteries respectively
What is the venous drainage of the scrotum?
Scrotal veins, drains into external pudendal veins
What is the cutaneous innervation of the antero lateral scrotum?
geintal branch of genitofermoal nerve
What is innervation for anterior and posterior scrotum?
Anterior and posterior scrotal nerves
What is the innervation of the inferior scrotum
Perineal branches of posterior femoral cutaneous nerve
What drains the lymphatics of the scrotum?
Superficial inguinal nodes
Where is the spermatic cord formed?
Deep inguinal ring
Through which canal does the spermatic cord enter?
inguinal canal
What are the 3 fascial layers of the spermatic cord and where are they each derived from?
- External spermatic fascia – derived from aponeurosis of external oblique
- Cremaster muscle and fascia – internal oblique and its fascial oblique
- Internal spermatic fascia – transversalis fascia
- 3 fascial layers also covered by layer of superficial fascia which lies underneath scrotal skin
What is the cremasteric reflex? How is it stimulated and which nerves are involved?
- Stimulated by stroking superior and medial thigh
- Produces contraction of cremaster muscle, elevating testis on ipsilateral side.
Spinal reflex consists of 2 parts:
- Sensory limb – genitofemoral nerve
- Motor limb – genital branch of genitofemoral nerve
Name the contents of the spermatic cord. there are 9 things!!!
Spermatic cord contents “3 arteries, 3 nerves, 3 other things”:
3 arteries: testicular, ductus deferens, cremasteric.
3 nerves: genital branch of the genitofemoral, cremasteric, autonomics.
3 other things: ductus deferens, pampiniform plexus, lymphatics.
What is the function of the vas deferens? What are its 3 layers?
- Takes sperm from epididymis to the ejaculatory duct.
- Wall contains a smooth muscle coat which consists of 3 layers – inner layer of longitudinal muscle, intermediate layer of circular muscle, outer layer of longitudinal muscle.
What is testicular torsion? How is it diagnosed?
- Spermatic cord twists upon itself leading to occlusion of testicular artery and necrosis of testes
- Diagnosis confirmed via ultrasound
What is the secretion of the prostate gland and what does it do?
- Secretes proteolytic enzymes into semen which act to break down clotting factors in the ejaculate.
- Allows semen to remain in a fluid state
What is the arterial and venous supply of the prostate?
Arterial – Prostatic arteries derived from internal iliac
Venous – Prostatic venous plexus, drains into internal iliac veins
What is the sympathetic, PS, and sensory innevation of the prostate?
Sympathetic, PS, and sensory form inferior hypogastric plexus.
How does benign prostatic hyperplasia present? Which area of the prostate enlarges?
- Compresses on both bladder and urethra
- Presents with urinary frequency, urgency and difficulty initiating micturition
- Enlargement in the transitional zone of prostate
How does prostatic carcinoma preesent? Which area of the prostate enlarges?
- Compresses on both bladder and urethra
- Presents with urinary frequency, urgency and difficulty initiating micturition
- Malignant cells commonly originate from peripheral zones, therefore symptoms present late in the disease.
What does the bulbourethral glands contribute to semen?
- Produce mucus secretion which serves as lubrication during sexual arousal.
- Secretions are alkaline and help to neutralise acidity of vagina.
Where is the bulbourethral gland found? What is its epithelium?
- Bulbourethral glands found enclosed within fibres of the external urethral sphincter.
- Lined by columnar epithelium
What is the vasculature of the bulbourethral gland?
Derived from arteries to the bulb of the penis
What is the innervation of the bulbourethral gland?
Prostatic plexus
What is the lymphatic drainage of the bulbourethral gland?
Internal and external iliac lymph nodes
What do the seminal vesicles contribute to semen?
Produces 70% of volume of semen:
- Alkaline fluid
- Fructose – provides energy source for spermatozoa
- Prostaglandins – Suppress the female immune response to foreign semen
- Clotting factors – designed to keep semen in the female reproductive tract post ejaculation
What is the internal lining of the seminal vesicles?
pseudostratified columnar
What structures are derived from mesonephric ducts embryologically?
SEED
Seminal glands, Ejaculatory ducts, Epididymis, Ductus deferens are all derived from mesonephric ducts.
What is the lymphatic drainage of the seminal vesicles?
external and internal iliac lymph nodes
What is a seminal gland abscess? how is it detected?
- Abscess formation in seminal glands allows pus to enter peritoneal cavity in event of rupture.
- Detected by DRE
How can seminal vesicles be used to diagnose STIs?
- Seminal glands can be massaged via DRE to release their secretions
- These can be collected and used for microscopy of STIs, e.g. gonorrhoea.
State the course of the vas deferens
- tail of epididymis
- inguinal canal
- side wall of pelvis
- joints ducts from seminal vesicle to form ejaculatory ducts
Which presents first: benign or cancer prostate? Why?
benign
Because the hypertrophy in benign occurs in the transitional zones of the prostate which is more medial
Why is a right sided varicocoele more worrying than a left sided one?
Right is more indicative of problems such as raised IVC pressure due to an obstruction
Right test vein attaches straight to IVC
Left sided is also more likely due to a lack of valves in the left test vein