Flashcards in Urinary and Sexual Dysfunction Deck (16):
What brain regions are necessary for volitional control of micturition?
the dorsomedial frontal lobe connected to the medial region of the pontine micturition center
What brain regions are necessary for volitional urine storage by producing a powerful contraction of the urethral sphincter?
the lateral pontine micturition center
What happens, then, with damage to the pontine micturition center?
you lose inhibitory control over the spinal reflexes, so when the bladder becomes distended, the micturition reflex is automatically triggered at the level of the spinal cord without the patient's awareness or control and you get detrusor hyperreflexia and incontinence
What is the name of the circuit that controls a reflex arc starting in the bladder and projecting to the pontine micturition center with outflow connections to the parasympathetic sacral spinal motor nuclei?
The micturition reflex is a spinal segmental reflex arc with afferent fibers from the detrusor muscle to what nucleus?
Onuf's nucleus in the sacral spinal cord at S2-S4
Where do the efferent fibers form Onuf's nucleus go?
through the pudendal nerves to the striated sphincter muscles
What is a normal PVR?
less than 50 ml
In a spastic bladder, what happens to capacity? Compliance?
capacity is decreased
compliance is reduced
In an atonic bladder, what happens to capacity? compliance?
increased capacity and increased compliance, so you get low voiding pressure and flow rate
What will cause a spastic bladder?
it's an UMN problem due to lesions involving the frontal lobes, pons or suprasacral spinal cord
What will cause an atonic bladder?
It's a LMN problem due to lesions at the level of the conus medullaris, cauda equine or sacral plexus
or it may reflect peripheral nerve dysfunction
Voiding dysfunction occurs in 40-70% of patients with Parkinson disease. What is the most common finding on urodynamics?
detrusor hyperreflexia, but also pseudodyssynergia as a consequence of sphincter bradykinesia
What will happen to urination in spinal cord injury?
you get detrusor hyperreflexia with loss of compliance and detrusor-sphincter dyssynergia
What are some examples of diseases that can damage the peripheral nerves causing bladder dysfunction?
diabetes is the big out
injury to pelvic nerves with local radiation or surgery
What are some medications that can be used for hypersensitive bladder with urge incontinence?
the anticholinergic agents like tolterodine, oxybutynin, trospium and solifenacin
TCAs liks imipramine and amitriptyline