Penis

Question 1

Parts of the penis?

Answer 1

Root
Body
Glans

Question 2

Where is the root of the penis located?

What is found in it?

Answer 2

In superficial perineal pouch of pelvic floor and not visible externally

Three erectile tissues - 2x crura plus bulb of penis

2 muscles - ischiocavernosus and bulbospongiosus

Question 3

Where is the body of the penis suspended from?

Answer 3

The pubic symphysis

Question 4

What is in the body of the penis?

Answer 4

3 cylinders of erectile tissue

• 2x corpus cavernosa
• 1x corpus spongiosum

Question 5

What is the glans formed from and what does it contain?

Answer 5

Distal expansion of the corpus spongiosum

External urethral orifice

Question 6

What passes through the corpus spongiosum

Answer 6

The urethra

Question 7

What are the left and right crura attached to in the bulb and what do they become as they enter the body of the penis?

Answer 7

Ipsilateral ischial ramus

Corpus cavernosa

Question 8

How is the urethra prevented from becoming occluded in an erection?

Answer 8

Corpus spongiosum fills to a reduced pressure

Question 9

Where does the corpus spongiosum lie in relation to corpora cavernosa

Answer 9

Ventrally

Question 10

Function of the bulbospongiosus?

Answer 10

There are two
Associated with the bulb
Contract to empty the spongy urethra of any residual urine or semen
Anterior fibres aid in maintaining an erection by increasing the pressure in the bulb

Question 11

Function of the ischiocavernosus?

Answer 11

One of these
Surround the left and right crura
Contract to force blood from the cavernous spaces into the corpus cavernosa which helps to maintain an erection

Question 12

What are the fascial coverings of the erectile tissue?

Answer 12

Deep fascia most superficially which is a continuation of the deep perineal fascia. Binds the erectile tissues together

Then tunica albuginea, which forms an individual capsule around each cavernous body

Question 13

Ligaments that support and attach the roof of the penis to surrounding structures?

Answer 13

Suspensory ligament - condensation of deep fascia, connects erectile bodies of the penis to the pubic symphysis

Fundiform ligament - condensation of of the abdominal subcutaneous tissue. Runs down the linea alba and surrounds the penis like a sling, attaching to the pubic symphysis

Question 14

What is the skin of the penis connected to?

Answer 14

The underlying tunica albuginea by loose connective tissue

Question 15

What is the foreskin/prepuce?

Answer 15

Double layer of skin and fascia, located at the neck of the glans and covers the glans
Connected to skin of the glans by the frenulum, a median fold of skin on the ventral surface

Question 16

What is the potential space called between the glans and the prepuce?

Answer 16

Prepupital sac

Question 17

Arterial supply to the penis?

Answer 17

Dorsal and deep arteries of the penis and bulbourethral artery
All branches of the internal pudendal, from the internal iliac

Question 18

What are the veins which drain the penis?

Answer 18

Cavernous spaces are drained by deep dorsal veins of the penis
Empty into the prostatic venous plexus
Superficial dorsal veins drain the superficial structures eg skin and cutaneous tissue

Question 19

Innervation of the penis?

Answer 19

S2-4 spinal cord segments and spinal cord ganglia
Sensory and sympathetic supply to the skin by the dorsal nerve of the penis, a branch of the pudendal
Parasympathetic by cavernous nerves from the prostatic nerve plexus - responsible for vascular changes causing an erection

Question 20

What is hypospadias?

Answer 20

A congential condition - born with the opening to the urethra on the ventral aspect of the penis
Corrected with surgery

Question 21

What is phimosis?

Answer 21

Where the prepuce fits tightly over the glans and cannot be retracted which can cause irritation when smegma (oily secretions) accumulates in the preputial sac

Question 22

What is paraphimosis?

Answer 22

More severe form of phimosis
Where retraction of the prepuce and glans constrict the neck of the glans
Interferes with venous/lymphatic drainage
May cause glans to enlarge so that the prepuce cannot be drawn over it

Question 23

What is Peyronie’s disease?

Answer 23

Abnormal curvature of the shaft due to build up of scar tissue
Can cause pain on erection
Surgical correction

Question 24

What is erectile dysfunction?

Answer 24

Inability to maintain an erection

Question 25

Causes of erectile dysfunction?

Answer 25

Often a vascular aetiology such as hypertension, hyoercholesterolaemia, diabetes
Anxiety or depression

Question 26

What is priapism?

Answer 26

Erection persisting for more than four hours without stimulation
Often painful and blood can become trapped in erectile bodies
If untreated, can cause ED and scarring

Question 27

Functions of the penis?

Answer 27

Sexual intercourse - erection, emission and ejaculation

Micturition