Urogynaecology

Question 1

What is the perineum and perineal body?

Answer 1

• Perineum = area between vestibule + anus, formed of ischiorectal fascia
• Perineal body = where the muscles insert, central tendon, contains the anal triangle, urogenital triangle + superficial perineal muscles. Is the bit torn/cut in parturition

Question 2

What are the pelvic floor muscles?

Answer 2

Puborectalis, pubococcygyeus, iliococcygeus and coccygeus

Coccygeus - innervated by anterior rami of S4-5
The other 3 make up levator ani -

Question 3

Describe the different levels of support of the pelvic organs

Answer 3

Level I: uterosacral ligaments (to upper vagina + cervix), arcus tendineous fasciae pelvis, ileopectineal ligament
Level II: medially from white lines to support A+P vaginal walls
Level III: perineal body + pubourethral ligaments

Question 4

Urethrocele and cystoceles

Answer 4

Urethra/bladder bulge into anterior wall of vagina - may see at intraoitus

• Urethroceles often due to damage to anterior level 3 support
• Cystoceles often due to damage to L2 supports

Question 5

Rectocele

Answer 5

Herniation of the rectum through a fascial defect, often a/w a lax perineum

Question 6

Enterocele

Answer 6

Small bowel prolapses through the PoD, usually there is also a uterine prolapse, or it happens post-hysterectomy (cos level I support is damaged)

Question 7

Uterine prolapses

Answer 7

Caused by deficient level I support, usually there’s also vaginal prolapse

• 1st degree - cervix descends in the vagina (often due to retroverted uterus)
• 2nd degree - cervix reaches intraoitus
• 3rd degree (procidentia) - cervix + body of uterus + vagina protrude through intraoitus

Question 8

What are the causes of pelvic prolapse?

Answer 8

• Congenitally weak supports
• Acquired (majority)
• High parity: laceration/overdistension/instrumental delivery that damage the pelvic floor
• Raised intra-abdominal pressure: chronic cough, constipation
• Hormonal changes: reduced oestrogen at menopause leads to atrophy and reduction in support

Question 9

Clinical features of prolapse?

Answer 9

• General: feeling of fullness and ‘dragging down’ discomfort in the vagina, protrusions through intraoitus, sacral backache (relief on lying down), often worse at end of the day, sexual dysfunction, dyspareunia
• Urethrocele/cystocele: may cause incomplete bladder emptying leading to recurrent UTIs, SUI, bulge in anterior wall on straining (seen with Sim’s speculum)
• Rectocele: defecation issues, reducible mass bulging into vagina, vaginal ‘flatus’
• Enterocele: if large may get incarceration or obstruction
• Uterine prolapse: discomfort on sitting, ulceration/bleeding, ureter compression causing UTI/hydronephrosis

Question 10

How may prolapses be prevented?

Answer 10

• Specific hysterectomy techniques
• Avoid prolonged 2nd stage of labour (pushing stage), avoid premature bearing down
• Pelvic floor exercises

Question 11

How are prolapses managed?

Answer 11

*Conservative: pelvic floor exercises, pessaries (need some pelvic floor support to keep it in, e.g. ring pessaries plus topical oestrogen if post-menopause)

Question 12

Outline the types of urinary incontinence

Answer 12

• True incontinence: continual loss of urine usually from a fistula but can be due to retention with overflow
• Stress UI: involuntary loss from brief increases in abdominal pressure without detrusor contraction, usually injury to continence mechanisms e.g. sphincter damage plus lack of oestrogen stimulation (as in menopause)
• Urge/overactive bladder UI: sudden detrusor contraction with uncontrolled loss of urine causing urgency, frequency, nocturna. May be idiopathic detrusor instability, obstructive uropathy, DM, neuro e.g. MS or damage in pelvic surgery
• Mixed UI: mix of SUI+UUI, involuntary leakage a/w sneezing coughing etc
• Overflow: obstruction so urine can’t go anywhere else but leak out e.g. detrusor fibrosis

Question 13

Clinical features of urinary incontinence

Answer 13

• SUI: leak on exertion often a small volume, may find a prolapse of the urethra + anterior vaginal wall
• UUI: leakage often a/w triggers for bladder contractions like cough (so can mistake for SUI), larger volume lost

Question 14

How may urinary incontinence be assessed?

Answer 14

• Exclude UTI
• Frequency-volume chart: SUI normal frequency + bladder capacity, UUI increased frequency
• Urodynamic studies

Question 15

How is stress urinary incontinence managed?

Answer 15

1st conservative: lose weight, stop smoking, treat chronic cough, pelvic floor training for at least 3m (8 contractions 3 times per day)
2nd surgery: tension-free vaginal tape (commonest), laparoscopic colposuspension, peri-urethral injection of a bulking agent
3rd medical: duloxetine (SNRI). S/e of anxiety, constipation, diarrhoea, dizziness, dry mouth, flushes, myalgia, palpitations, skin reactions, weight changs

Question 16

How is urge urinary incontinence managed?

Answer 16

1st conservative: moderate fluid intake, reduce caffeine + alcohol, bladder training (minimum 6w, gradually increase intervals between voiding)
2nd medical: anticholinergics e.g. oxybutynin (avoid in frail older women), tolteridone, solifenacin (act on M2 or M3 receptors); intravaginal oestrogens for atrophy, botulinum toxin A, neuromodulation e.g. sacral nerve stimulation; mirabegron (beta 3 agonist) if needing to avoid anti-cholinergic s/es
3rd surgical: detrusor myomectomy and augmentation cystoplasty

Question 17

What supports the vagina?

Answer 17

Anterior - pubovesicalcervical fascia
Posterior - rectovaginal septum
Lower - puborectalis muscle

Question 18

What supports the uterus?

Answer 18

Vaginal walls and uterosacral ligaments (the round + broad ligaments are weak)

Question 19

What are the issues with pessaries for prolapse?

Answer 19

• They need to have some pelvic floor strength to keep it in
• S/e can include ulceration and bladder-vagina fistulae
• They need replacing every 4-6 months

Question 20

What are the contraindications + s/es for use of anticholinergics in urinary incontinence?

Answer 20

CI: acute glaucoma, myasthenia gravid, bowel obstruction

S/e: CPCSCSCS, xerophthalmia, arrhythmias, confusion

Question 21

Which tissues control micturition?

Answer 21

• Detrusor muscle in bladder wall
• Internal urethral sphincter - smooth muscle that in men prevents sperm going into the bladder but in women is virtually absent
• External urethral sphincter - voluntary skeletal muscle, used to hold urine in when bladder is full

Question 22

Why do babies have no control over their voiding?

Answer 22

Micturition is a spinal reflex with descending modulation, babies haven’t developed the descending modulation so when bladder reaches a certain level it voids

Question 23

Outline the voiding reflex

Answer 23

• Micturition centre stimulated by high frequency activity in the sensory neurone (full bladder)
• Parasympathetic fibres activated to contract the detrusor
• Inhibitory signals sent to the M centre when not near a toilet to hold off, then excitatory signals when able to use toilet
• M centre sends inhibitory signals to the L centre to inhibit the storage phase when voiding which relaxes the IUS + stops sympathetics
• Rhythmic contractions of detrusor expel urine

Question 24

What nerves control micturition?

Answer 24

• Pelvic nerve: PNS, branch of sacral n S2-4. Causes detrusor contraction for voiding
• Sensory pelvic n: S2-4, stimulated when bladder stretched
• Pudendal nerve: S2-4, somatic branch of sacral, voluntary control of the EUS (contracts)

Question 25

What is the effect of a LMN lesion on micturition?

Answer 25

Bladder disconnected from higher centres so low detrusor pressure is sensed so sphincters relaxed - don’t feel bladder filling - large residual urine, lack of sense of needing to void, overflow incontinence

S2-4 affected - reduced perineal sensation + lax anal tone

Question 26

What is the effect of a UMN lesion on micturition?

Answer 26

Dilated ureters, thickened muscle, high pressure contractions, poor sphincter coordination, constantly in active mode (so urine moves up into ureters/kidneys)

Question 27

What are the RF for urinary incontinence?

Answer 27

• Predisposing: FH, race, anatomical/neurological variants
• Promiting: menopause, drugs, UTI, increased IAP, age, co-morbidities, obesity
• O+G: pregnancy, childbirth, pelvic surgery, prolapse

Question 28

What investigations are indicated in urinary incontinence?

Answer 28

• Bladder diaries minimum 3d
• Vaginal examination - pelvic organ prolapse + ability to initiate voluntary contraction of PF muscles
• Urine dip + culture
• Urodynamic studies