Sexual Medicine and Andrology

Question 1

Process of ejaculation: Ejection

Answer 1

• Forcel contractions of the bulbospongiosus and ischiocavernosus in coordinatino with the external urethral sphinter lead to expulsion of semen.

Tight coaptation of the bladder neck is needed to prevent retrograde ejaculation

Process is mediated by the Somatic NS S2- S4 (not the bladder neck contraction)

Question 2

Process of ejaculation: Emission

Answer 2

• Sperm from vas is deposited in the posterior urethra along with seminal fluid form the prostate and SV.

Bladder neck closes tightly to prevent retrograde ejaculation.

Under control of the sympathetic nervous system T10 - T12extending to the pelvic plexus then to the hypogastric nerves.

Question 3

Part of brain that plays a central role in ejaculation in animal models

Answer 3

medial pre-optic area MPOA

stimulation induces ejaculation whereas ablation prevents it.

Question 4

Medications approved by the FDA in the management of PE

Answer 4

None.

All meds are classified as off-label and include SSRIs: paroxetine, sertraline, Fluoxetine, TCA, Clomipramine, topical anesthetics

Question 5

PDE5i MOA

Answer 5

PDE5i are competitive inhibitors of PDE5 by binding to the catalytic domain48 and hence promote high levels of cGMP in the penile vasculature

Question 6

When should Sildenafil or Vardenafil be taken

Answer 6

1-2 hours prior to a meal.

Both are pyrazolopyrimidine compounds. Absorption is lowed by dietary lipids.

Peak absorption is 30-60 mins and T1/2 = 3-5 hours

Question 7

PDE5i contraindications

Answer 7

The only strict contraindication to use of PDE5i is concurrent use of nitrate containing medications (e.g. sublingual nitroglycerin, isosorbide mononitrate or dinitrate)

PDE5i can also potentiate the hypotensive effect of alpha blockers

PDE5i are metabolized primarily by the cytochrome CYP3A4 system

Question 8

PDE5i Adverse Events

Answer 8

The most common adverse events (AE) associated with this class of medications include headache, facial flushing, dyspepsia/heartburn, nasal congestion, visual changes, and myalgia

Question 9

Phases of Male Sexual Response

Answer 9

• excitement/arousal: tachycardia, increase in blood pressure, penile erection, testicular retraction, sexual excitement

*Plateau: tachycarda, increase in blood pressure, muscle contraction, increasing sexual excitement.

*Orgasm: Pelvic muscular contractions, ejaculation, intense pleasure or satisfaction

*Resolution: Loss of penile erection, decline in heart rate, blood pressure, decreasing sexual excitement, refractory period

Question 10

When is penile duplex doppler ultrasound indicated

Answer 10

i) patients with a high likelihood of psychogenic ED, to establish the absence of an organic etiology and provide reassurance to the patient,

(ii) men with the possibility of arteriogenic ED, where cardiology evaluation may be indicated,

(iii) young men with a history of pelvic trauma who might be candidates for surgical revascularization,

(iv) men with Peyronie’s disease who are considering invasive intervention, and

(v) identification of men with severe veno-occlusive dysfunction who are unlikely to respond to medical therapy and should consider surgical intervention

Question 11

What values are considered as evidence of arterial insufficiency vs venous leak

Answer 11

PSV < 25-30 cm/sec is considered evidence of arterial insufficiency (arteriogenic ED) and EDV > 5 cm/sec is consistent with venous leak

Question 12

How can the dx of veno-occlusive dysfunction as cause of ED be confirmed?

Answer 12

cavernosography

Question 13

Describe the phases of an erection

Answer 13

1. Flaccid: Arterial flow is low and corporal resistance is high d/t contraction of smooth msucle in the corporal arteries. pO2 is low at 35mmhg
2. Filing: Increasing firmness of the penis from increased blood flow
3. Full erection phase: erection of the penis to a non-dependent position. Partial pressure of O2 increase to 90 mmHg
4. Rigid Erection: Engorgement of the coprus spongiosum occurs as blood is forced into the penis by contraction of the pelvic floor musculature, intra-penile pressure may exceed systolic blood pressure.

Question 14

Phases of penile detumescence

Answer 14

1. Slight rise in intracoporal pressure related to construction of the cavernousus arteries against the engorged spongy tissues of the corpora cavernosa
2. slow process of detumescence as partial venous drainage resumes
3. Third and final phase of detumescence is rapid and associated with complete restoration of venous drainage.

Question 15

How does hyprolactinemia contribute to ED

Answer 15

Suppresses LH secretion

may be a/w prolactin secreting adenoma or medications that results in prolactin level increases

Question 16

How does hyperthyroidism contribute to ED

Answer 16

Hyper-estrogenism

Question 17

Medications a/w ED

Answer 17

-5-Alpha Reductase Inhibitors

Anti-androgens

LH-RH agonists/antagonists

Anti-hypertensives

H2 Blockers

Psychiatric Drugs

Digoxin