A brief slide presentation on the physiology of erection and all about the Dysfunction

1. ERECTILE DYSFUNCTION

2. Definition
Erectile dysfunction, also known as impotence, is defined by the inability to attain or maintain
erection sufficient for sexual satisfaction including satisfactory sexual performance . It's been reported that
more than half of men between the ages of 40 and 70 experience some form of ED. It affects 25% of men
>65.
It is the most common form of sexual dysfunction in men, it can usually co-exist with decreased libido
and Premature ejaculation.
Erection and Ejaculation are innervated by the PSNS and the SNS respectively, In ED we would be focusing
more on Erectile aspect.
Mechanism of Erection
The corpora cavernosa is lined by endothelial cells and it is able to store blood, corpus spongiosum lies
underneath it and contains the urethra. Blood flows to the penis via the cavernosal artery and out through
the circumplex vein to drain into the deep dorsal vein.
PSNS is responsible for erection so when it is stimulated ACH is released and in the process nitric oxide
is produced to inhibit contraction and Vasodilation then occurs.

4. CAUSES OF ERECTION
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5. DIAGNOSIS OF ERECTILE DYSFUNCTION
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6. Psychogenic/ Non- Organic ; Performance anxiety, history of sexual trauma, relationship problems, depression.
Risk factors for ED
• Age
• Alcohol and Recreational drug use
• Sedentary lifestyle
• Chronic kidney disease
• Coronary artery disease(This is not a cause but a marker for presence of systemic atherosclerosis
causing the ED. CAD is a risk for ED and vice versa
Assessment of ED
1. History
- Time course
-situational factors
-sexual history(low libido accompanying ED suggests depression or decreased testosterone
-Interview partner with consent (can reveal possible psychogenic factors)
- GU history( prostate surgery, pelvic radiation, pelvic trauma).
-PMH( diabetes, hypertension, hyperlipidemia, CAD, CKD(chronic kidney disease)

7. 2. Focused physical Exam​
- Vitals( hypertension and Obesity)
- GU exam( penile plaques indicative of peyronie's disease, Testicular size ( small testicles are
indicative of hypogonadism)
- peripheral evidence of decreased Testosterone such as Gynecomastia
- assess for evidence of systemic atherosclerosis(peripheral pulse, look for evidence of vascular
disease)
- Cremasteric reflex( contraction of the ipsilateral scrotum, absence of reflex suggests neurogenic
ideology)
3. Neurological assessment
4. LAB workup
o HBA1C
o Lipid panel
o Complete metabolic panel
o (morning )serum Testosterone(-Total testosterone, -Testing unbound testosterone)
o Prolactin( not necessary to check unless there are indicative signs of decreased testosterone
o Nocturnal penile Tumescence test

8. o Urine tests
o Duplex Ultrasound( to evaluate blood flow and check for
atherosclerosis)

10. TREATMENT
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11. 2nd line treatment:
where no response to sildenafil at 100mg when required,
• Tadalafil 10mg ONCE WEEKLY when required for 1 month Review and if necessary increase to 20mg once
weekly when required OR
• Vardenafil tablets – 10 mg ONCE WEEKLY when required for 1 month (5mg for patients on
alpha blocker)
3rd line: REFER TO ED CLINIC:
Where patient has failed to respond to the maximum dose of at least two oral PDE-5 inhibitors refer to specialist.
Treatments suitable for prescribing by general practitioner, following initiation by specialist include (in no
particular order):
• Vacuum erection devices (sometimes used in combination with PDE-5i)
• Prosthetic Implants( don’t cause erection but help keep the penis rigid)
• Alprostadil cream, 200 – 300 micrograms sachet once weekly when required
• Intra-cavernous alprostadil (Caverject or Viridal Duo) -Usual dose 5- 20 micrograms (max 60 micrograms)
when required once weekly [Rarely used in combination with PDE-5i, unlicensed indication]
• Intraurethral alprostadil (MUSE) – usual dose 125 micrograms – 1 mg when required once weekly
• Invicorp® (aviptadil 25micrograms and phentolamine 2mg) solution for intra-cavernosal injection. Use once
weekly when required

13. REFERRAL
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14. https://www.guidelines.co.uk/mens-health/guidelines-on-the-
management-of-erectile-dysfunction/247615.article
https://www.youtube.com/watch?v=NAMDHH5h3Ak
https://www.youtube.com/watch?v=33m9pN_vAI4
https://www.youtube.com/watch?v=G6oeCkp1xaQ