3.4 Benign Pelvic Masses, Pelvic Organ Prolapse & Urinary Incontinence

Benign Pelvic Masses, Pelvic Organ Prolapse & Urinary Incontinence

Benign Adnexal Masses

Adnexal masses are common clinical findings across the female lifespan, but their differential diagnosis and management differ fundamentally between premenopausal and postmenopausal individuals. In premenopausal patients, greater than 90% of adnexal masses are benign, whereas postmenopausal masses carry a substantially higher risk of malignancy, requiring risk stratification via serum CA-125, the Risk of Ovarian Malignancy Algorithm (ROMA), or multimodal ultrasound criteria (e.g., IOTA simple rules).

Ovarian Torsion: A Surgical Emergency

Ovarian torsion occurs when the ovary and often the fallopian tube twist around their vascular axis (the infundibulopelvic ligament and utero-ovarian ligament), obstructing venous and lymphatic outflow, causing massive stromal edema, and culminating in arterial thrombosis and ischemic necrosis.

• Risk Factors: Adnexal masses 5 to 10 cm in diameter have the highest propensity to twist. Benign cystic teratomas and functional cysts are the most common culprits. Torsion rarely occurs with malignant or endometriotic masses due to dense adhesive fixation.
• Clinical Presentation: Sudden-onset, severe, sharp, unilateral lower quadrant pelvic pain, frequently accompanied by waves of nausea and vomiting (>70% of cases). A low-grade fever or leukocytosis may signify tissue necrosis.
• Management: Emergent diagnostic laparoscopy is the gold standard. Current clinical standards dictate prompt laparoscopic detorsion with ovarian preservation, regardless of a dark or cyanotic appearance, as substantial follicular function recovers in the majority of conserved ovaries. Oophorectomy is reserved for overt gangrenous necrosis or postmenopausal women.

Pelvic Organ Prolapse (POP)

Pelvic organ prolapse (POP) involves the descent of one or more pelvic structures—the anterior vaginal wall, posterior vaginal wall, cervix/uterus, or vaginal apex—into or beyond the vaginal canal.

Anatomical Compartments

• Anterior Compartment (Cystocele): Herniation of the bladder base into the anterior vaginal wall, resulting from attenuation of the pubocervical fascia.
• Posterior Compartment (Rectocele): Protrusion of the anterior rectal wall into the posterior vagina due to defects in the rectovaginal septum.
• Apical Compartment (Uterine Prolapse or Vaginal Vault Prolapse): Descent of the cervix and uterus down the vaginal axis, or eversion of the vaginal apex (cuff) following prior hysterectomy.
• Enterocele: Herniation of peritoneal small bowel loops through the pouch of Douglas into the upper posterior vaginal canal.

Risk Factors

Predisposing factors include vaginal parity (with risk rising steeply with operative forceps deliveries), advancing age, hypoestrogenism, elevated chronic intra-abdominal pressure (chronic cough, constipation with repetitive straining, heavy occupational lifting, obesity), and genetic connective tissue disorders (e.g., Ehlers-Danlos syndrome).

Staging Systems: Baden-Walker Versus POP-Q

While the older Baden-Walker Halfway System utilizes grades 0 through 4 based on subjective relation to the hymenal ring, modern evidence-based practice and board certification examinations rely on the Pelvic Organ Prolapse Quantification (POP-Q) system:

POP-Q Staging Criteria (Points measured in cm relative to the hymen during maximum Valsalva):
  - Stage 0: No prolapse; points Aa, Ap, Ba, Bp are -3 cm; C/D between -tvl and -(tvl-2 cm).
  - Stage I: Most distal portion of the prolapse is >1 cm above the hymen (<-1 cm).
  - Stage II: Most distal portion of prolapse is between 1 cm above and 1 cm below the hymen (-1 cm to +1 cm).
  - Stage III: Most distal portion of prolapse is >1 cm below the hymen, but <(tvl - 2 cm).
  - Stage IV: Complete eversion of the vaginal canal (procidentia); leading edge protrudes ≥(tvl - 2 cm).

Management of POP

• Conservative Therapies:
  • Pelvic Floor Muscle Training (PFMT): Supervised Kegel exercises strengthen the levator ani complex, highly effective for symptom reduction in Stages I and II.
  • Vaginal Pessaries: First-line non-surgical therapy across all prolapse stages. Support pessaries (Ring with support) are ideal for early stages and sexually active patients. Space-occupying pessaries (Gellhorn, Cube) are required for Stage III/IV prolapse or compromised perineal bodies.
  • Pessary Care: Periodic removal and cleaning are essential. In postmenopausal patients, concurrent low-dose topical vaginal estrogen cream should be prescribed to prevent mucosal erosion, ulceration, and bleeding.
• Surgical Management: Reconstructive surgery (sacrocolpopexy, sacrospinous ligament fixation, colporrhaphy) restores anatomy, while obliterative surgery (colpocleisis) closes the vaginal lumen in patients who do not desire future coitus.

Urinary Incontinence (UI) in Women

Urinary incontinence is the involuntary loss of urine, categorized into distinct clinical phenotypes:

Stress Urinary Incontinence (SUI)

• Mechanism: Involuntary leakage upon exertion, coughing, sneezing, laughing, or position change in the absence of a detrusor contraction. Etiologies include urethral hypermobility (insufficient pelvic floor and endopelvic fascial support permitting downward rotation of the bladder neck under abdominal pressure) and intrinsic sphincter deficiency (ISD) (loss of mucosal coaptation and intrinsic sphincter closure tone).
• Evaluation: Visualized transurethral leak during an office Cough Stress Test; Q-tip test demonstrating resting-to-straining angle excursion >30 degrees (hypermobility). Post-void residual (PVR) is normal (<50–100 mL).
• Management: PFMT (3 sets of 10–12 contractions daily for ≥3 months); continence pessaries (incontinence dish with knob); midurethral synthetic sling (tension-free vaginal tape [TVT] or transobturator tape [TOT]), which remains the surgical gold standard.

Urge Urinary Incontinence (UUI) & Overactive Bladder (OAB)

• Mechanism: Involuntary leakage accompanied or immediately preceded by intense urgency, driven by uninhibited detrusor muscle contractions during bladder filling (detrusor overactivity). Overactive bladder syndrome consists of urgency, frequency (≥8 voids/24h), and nocturia (waking at night to void), with (OAB-wet) or without (OAB-dry) urge incontinence.
• Management:
  • First-line: Behavioral therapy (scheduled voiding, bladder training intervals, urge suppression techniques, fluid management, avoiding caffeine/alcohol).
  • Second-line: Antimuscarinics (oxybutynin, tolterodine, solifenacin) block M2/M3 receptors; adverse effects include dry mouth, constipation, and cognitive impairment in older adults. Beta-3 adrenergic agonists (mirabegron 25–50 mg daily, vibegron 75 mg daily) stimulate detrusor relaxation without anticholinergic cognitive side effects; mirabegron requires blood pressure monitoring (contraindicated in severe uncontrolled hypertension BP ≥180/110 mmHg).
  • Third-line: Intravesical onabotulinumtoxinA injections, sacral neuromodulation (InterStim), or percutaneous tibial nerve stimulation (PTNS).

Mixed & Overflow Incontinence

• Mixed Incontinence (MUI): Concomitant stress and urge components; clinical management focuses on identifying and treating the most bothersome symptom first.
• Overflow Incontinence: Continuous dribbling resulting from impaired detrusor contractility (diabetic neuropathy) or anatomical outlet obstruction (severe prolapse). Characterized by an elevated post-void residual volume (PVR >200–300 mL). Treatment involves clean intermittent catheterization (CIC) or relieving obstruction (pessary reduction); antimuscarinics are strictly contraindicated.