Erectile Dysfunction Flashcards
What nerve causes an erection?
Parasympathetic S2-4
What nerve causes ejaculation?
Sympathetic T11-L2
What position is the anatomical penis?
Erect (don’t get ventral and dorsal confused)
Which nerves are responsible for transmitting sensory information from the penis to the spinal cord? (somatic nerve)
Afferents dorsal penile nerves
(touch, pressure, temperature, pain)
Where does the pudendal nerve arise from?
The S2-4 nerve roots of the sacral plexus
What does the pudendal nerve innervate?
The perinuem, external genitalia, anus and associated pelvic floor muscles.
Sensory fibres within the pudendal nerve transmit information about touch, pressure, pain, and temperature from the ______ region to the spinal cord
perineal
The pudendal nerve also plays a crucial role in the motor control of the pelvic floor muscles, contributing to voluntary control over ____ and _____.
urination and defecation
What do the efferent pathway from Onuf’s nucleus innervate?
Ischiocavernosus muscle (contraction contributes to rigidity of erection)
Bulbocavernosus muscle (contraction assists in aiding ejaculation)
Which nerve do the efferent signals from Onuf’s nucleus travel through to reach the muscles they control?
Pudendal nerve (S2-4)
What are the regions within the hypothalamus that help control sexual response including erection?
Medial Preoptic Area (MPOA)
and
Paraventricular nucleus (PVN)
What is a useful acronym for the causes of erectile dysfunction?
IMPOTENCE
What does I in IMPOTENCE stand for?
Inflammatory:
prostatitis
What does M in IMPOTENCE stand for?
Mechanical:
Peyronie’s disease (fibrous scar tissue or plaques in penile tissue)
What does P in IMPOTENCE stand for?
Psychological:
Depression, anxiety, stress, relationship difficulties
What does O in IMPOTENCE stand for?
Occlusive (vascular):
Smoking, PVD, HTN, hyperlipidaemia, DM
What does T in IMPOTENCE stand for?
Trauma:
pelvic fracture, SCI (spinal cord injury), penile fracture (rupture of tunica albuginea, fibrous covering surrounding corpora cavernosa, by sudden and forceful bending or snapping of erect penis)
What does E in IMPOTENCE stand for?
Extra:
Pelvic surgery, prostatectomy, priapism, penile cancer
What does N in IMPOTENCE stand for?
Neurogenic:
MS, stroke, spina bifida, peripheral neuropathy
What does C in IMPOTENCE stand for?
Chemical:
antihypertensive, antidepressants, antipsychotics, anticonvulsants, statins, GNRH analogues, alcohol, cannabis, cocaine, heroin, diuretics
What does E in IMPOTENCE stand for?
Endocrine:
DM, hypogonadism, hyperprolactinaemia, hypothyroidism, hyperthyroidism, hypocortisolism, hypercortisolism
How do you assess for erectile dysfunction?
Cardiovascular
Abdomen
Neurological
Penis: Peyronie’s plaques, phimosis, deformities/lesions
Testes: presence, size and location
DRE: assess prostate
What investigations do you do for erectile dysfunction?
Blood pressure
Essential bloods: fasting glucose and lipids, early morning testosterone
Other bloods
MRI
What is first line treatment for erectile dysfunction?
PDE5 inhibitors: sildenafil (viagra), tadalafil
(1st line, oral meds. Contraindications = stroke, heart attack or arrhythmia in last 5 years, Tamsulosin don’t give viagra)
What is second line treatment for erectile dysfunction?
Alprostadil (synthetic PGE1)
Intraurethral or injections.
Can be painful
What is 3rd line treatment for erectile dysfunction?
Vacuum pumps with constriction band
What is a surgical option for erectile dysfunction?
Penile Implant
(can get infected, bruising)
What causes premature ejaculation?
Unknown
Perhaps to do with anxiety, reduced frequency of intercourse, obesity, prostatitis
