8 - Repro - Male repro system 2

Question 1

Which part of the prostate is affected by BPH? What are the implications of this?

Answer 1

Middle lobule of Prostate

Compresses urethra = dysuria, nocturia, urgency

Question 2

Describe the difference in PSA levels between BPH and prostatic malignancies:

Answer 2

BPH = normal or slightly raised PSA

Prostatic malignancies = markedly raised PSA

Question 3

In which 2 ways does prostatic cancer commonly metastasise?

Answer 3

1) via lymph - to internal iliac and sacral nodes

2) via venous blood - to internal vertebral plexus - to brain and vertebrae

Question 4

Which lobe of the prostate is palpated during a DRE?

Answer 4

Posterior lobe of prostate

Question 5

To which lymph nodes does prostatic cancer metastasise to first?

Answer 5

• Internal iliac nodes

- Sacral nodes

Question 6

Name the 3 erectile tissues present in the root of the penis:

Answer 6

2 x crura (of corpora cavernosum)

1 x bulb (of corpus spongiosum)

Question 7

Name the 2 muscles in the root of the penis:

Answer 7

1) Bulbospongiosum

2) Ischiocavernosus

Question 8

What is the function of the bulbospongiosum muscle, and in what part of the penis is it found?

Answer 8

• Expels last drops of urine from penis
• Maintains erection
• Root of penis

Question 9

What is the function of the ischiocavernosum muscle, and in what part of the penis is it found?

Answer 9

• Compresses veins, maintaining an erection

- Root of penis

Question 10

Name the 3 erectile tissues present in the body of the penis:

Answer 10

2 x corpora cavernosum

1 x corpus spongiosum

Question 11

Which erectile tissue of the penis surrounds the urethra?

Answer 11

Corpus spongiosum

Question 12

Th expansion of which erectile tissue forms the glans of the penis?

Answer 12

Corpus spongiosum

Question 13

Name the arteries which lie either side of the corpus spongiosum:

Answer 13

Bulbourethral arteries

Question 14

Name the arteries which run through the middle of each corpora cavernosum muscle:

Answer 14

Deep arteries of the penis

Question 15

Which part of the urethra is the least distensible, and why?

Answer 15

Membranous part

- Due to surrounding sphincter urethrae muscle, and perineal membrane

Question 16

What is the arterial supply to the penis?

Answer 16

Internal pudendal artery (from int. iliac) forms:

• Dorsal arteries of penis
• Deep arteries of penis
• Bulbourethral arteries

Question 17

What is the venous drainage of the penis?

Answer 17

• The cavernous spaces drain into venous plexuses, into the deep dorsal veins of the penis
• Skin and cutaneous tissue drains into superficial dorsal veins

Question 18

Name the fibrous tissue which envelopes the corpora cavernosum:

Answer 18

Tunica albuginea

Question 19

How does an erection occur?

Answer 19

• Vasodilation of coiled arteries of the corpora cavernosum increases blood flow
• Tunica albuginea resists expansion, occluding the venous plexuses in the penis
• Contraction of bulbospongiosus and ischiocavernosus also occludes venous plexuses
  = Penis becomes ingorged with blood = increased pressure

Question 20

Where do the lymphatics of the penis drain to?

Answer 20

• Into deep inguinal nodes (femoral triangle)

Question 21

Which nerves innervate the penis?

Answer 21

Sensory + Sympathetic = Dorsal nerve of the penis (Pudendal nerve) S2-4
Parasympathetic = Pelvic nerve S2-4

Question 22

Which nerve causes ejaculation?

Answer 22

Dorsal nerve of the penis (Pudendal nerve) L1/2

Question 23

Which nerve causes erection?

Answer 23

Pelvic nerve S2-4

Question 24

List some physical causes of erectile dysfunction:

Answer 24

• Vasculogenic: CVD/hypertension/diabetes
• Neurogenic: MS/Parkingsons/Stroke
• Hormonal: Hypogonadism/Thyroid disease
• Anatomical: Peyronie’s disease

Question 25

List some pharmacological causes of erectile dysfunction:

Answer 25

• Diuretics
• Antihypertensives
• Antipsychotics
• Antidepressants

Question 26

List some psychological causes of erectile dysfunction:

Answer 26

• Depression
• Anxiety
• Abuse-related conditions

Question 27

How does viagra result in erection?

Answer 27

• Inhibits cGMP breakdown in corpora cavernosum
  = NO stimulated vasodilation
  = Erection