Pelvic Organ Prolapse (POP) - An overview

Contents

Descent of female genital organs beyond their normal anatomical confines.

Accounts for 20% of women waiting for major gynecological surgery
Leading indication for hysterectomy in postmenopausal women

Classification

Anterior vaginal wall prolapse:

Cystocele (M/C POP): Bladder into vagina
Urethrocele: Urethra into vagina
Cystourethrocele: Bladder & urethra into vagina

Posterior vaginal wall prolapse:

Enterocele: Small intestine into vagina
Rectocele: Rectum into vagina

Apical vaginal prolapse:

Uterine prolapse: Uterus into vagina
Vaginal vault prolapse (roof of Vagina): After hysterectomy

Above: normal position of organs in the abdomen; Below: left: bladder prolapse, middle: uterine prolapse, right: posterior vaginal prolapse (rectocele) | InformedHealth.org [Internet]. Cologne, Germany: Institute for Quality and Efficiency in Health Care (IQWiG); 2006-. Pelvic organ prolapse: Overview. 2018 Aug 23. Available from: https://www.ncbi.nlm.nih.gov/books/NBK525783/

Etiology

Weakening of uterine supports:
Usually an elderly multiparous woman

General: Advancing age, parity, elevated body mass index, connective tissue disorders (e.g., Ehlers-Danlos syndrome)
Genetics: Family history of prolapse
Increased intra-abdominal pressure: Chronic cough, constipation, repeated heavy lifting
Obstetric: Operative vaginal delivery, vaginal delivery, birth trauma
Previous surgery: Hysterectomy/previous prolapse surgery

Congenital prolapse:
Young nulliparous woman

Connective tissue disorders (e.g. Ehlers-Danlos syndrome)
Spina bifida
Osteogenesis imperfecta

Anatomy

Loss of support to the uterus, bladder and bowel leading to their descent from the normal anatomic position towards or through the vaginal opening.

Mechanical support:

Angle of anteversion (b/w vagina & cervix): 90°
Angle of anteflexion (b/w uterus & cervix): 120°

Ligament support:

Primary supports: Triradiate ligament
1. Cardinal/transverse cervical/Mackenrodt’s ligament (strongest)
2. Uterosacral ligament (prevents uterine retroversion)
3. Pubocervical ligament (weakest)
Secondary support: Round ligament
No support: Broad ligament (peritoneum)

The major ligaments of the cervix | Sexmale Bodyfemale Bodyby. (2020) Ligaments of the Female Reproductive Tract – TeachMeAnatomy. Retrieved November 06, 2020, from https://teachmeanatomy.info/pelvis/female-reproductive-tract/ligaments/

Muscle support:
BLESSD

Bulbospongiosus muscle (medially)
Levator ani or pelvic diaphragm: Pubococcygeus & iliococcygeus (M/imp support of uterus)
External anal sphincter
Superficial transverse perinii muscle
External urinary sphincter
Deep transverse perinii muscle

Muscles not supporting uterus:
- Ischiocavernosus
- Ischiococcygeus

Delancey’s three integrated levels of pelvic support:

Level 1: Cardinal-uterosacral ligament complex (apical attachment of the uterus and vaginal vault to the bony sacrum)
Level 2: Arcus tendineous fascia pelvis and the fascia overlying the levator ani muscles (provide support to the middle part of the vagina)
Level 3: Urogenital diaphragm and the perineal body (provide support to the lower part of the vagina)

Delancey's three integrated levels of pelvic support — Delancey’s three integrated levels of pelvic support: Illustration of the normal vaginal axis and the three levels of support of the vagina and uterus from the perspective of a standing woman. In level I, the endopelvic fascia suspends the upper vagina and cervix from the lateral pelvic walls. Fibres of level I extend both vertically and posteriorly toward the sacrum. In level II, the vagina is attached to the arcus tendineus fasciae pelvis and superior fascia of the levator ani muscles. In level III, the distal vagina is supported by the perineal membrane muscles. The insets show transverse sections made through the vagina perpendicular to the normal axis at each level. | Barber, M. D. (2005). Contemporary views on female pelvic anatomy. Cleveland Clinic Journal of Medicine, 72 Suppl 4, S3-11.

Presentation

The majority of patients who present with pelvic organ prolapse do not report symptoms. Patients that do present with symptoms, however, often describe a sense or feeling of a bulge protruding through the vaginal opening.

Bearing-down sensation
Heaviness with urination/defecation
Discomfort in the lower abdomen
Severe cases: Uterus/bladder may even protrude out of the vagina grossly visible

Coexisting pelvic floor disorders:

Urinary incontinence (40%)
Overactive bladder (37%)
Fecal incontinence (50%)

Negatively effects sexual activity, body image, and quality of life

Complications

UTI
Kinking of ureter → Hydroureter → Hydronephrosis
Incarceration of prolapsed part (d/t venous congestion)
Cancer (rare)

Diagnosis

Valsalva manoeuvre:
Forced attempted exhalation against a closed airway over ≥6 seconds in whichever position maximum protrusion is best demonstrated (supine, left lateral or standing).

MRI:

Photographs in lithotomy position and sagittal magnetic resonance imaging showing vaginal-wall prolapse. Prolapse might include (top to bottom): anterior wall, vaginal apex, or posterior wall. Color codes include purple (bladder), orange (vagina), brown (colon and rectum), and green (peritoneum). | Jelovsek JE, Maher C, Barber MD. Pelvic organ prolapse. Lancet . 2007;369(9566):1028.

Pelvic Organ Prolapse Quantification System (POP-Q):
Standardized tool for documenting, comparing, and communicating clinical findings with proven interobserver and intraobserver reliability

Points and landmarks for POP–Q system examination

An example of measurements using the POP–Q system

Stage 0: No prolapse (points Aa, Ba, Ap, Bp are all -3, and either C or D is within 2 cm of TVL)
Stage I: Distal most point >1 cm above hymen
Stage II: Distal point within 1 cm of either side of hymen
Stage III: Distal point >1 cm but < (TVL-2) cm beyond hymen
Stage IV: Complete eversion of the vagina, usually with the leading point being the cervix/vaginal cuff. Distal point is at least (TVL-2) cm beyond the hymen

Baden–Walker half way system:

Baden–Walker half way system: It consists of four grades: grade 0 – no prolapse, grade 1–halfway to hymen, grade 2 – to hymen, grade 3 – halfway past hymen, grade 4 –maximum descent. | Persu, C., Chapple, C. R., Cauni, V., Gutue, S., & Geavlete, P. (2011). Pelvic Organ Prolapse Quantification System (POP-Q) – a new era in pelvic prolapse staging. Journal of medicine and life, 4(1), 75–81.

Differential diagnosis:

Congenital elongation of cervix
Vulval/Gartner cyst
Cyst of anterior vaginal wall
Urethral diverticula
Cervical fibroid/polyp
Chronic inversion of uterus
Rectal prolapse

Management

Pelvic floor muscle training (PFMT) (Kegel):

Improve symptoms associated with stress, urge, and mixed urinary incontinence and may result in a small improvement in symptoms in women with mild prolapse.
Does not reverse/treat pelvic organ prolapse
Good results are generally achieved with 45 to 60 exercises per day, divided into two to three sets.

Pessarie:
Viable option for all stages of prolapse, and may prevent progression of prolapse and avert or delay the need for surgery

Ring pessary in situ | Iglesia, C. B., & Smithling, K. R. (2017). Pelvic Organ Prolapse. American Family Physician, 96(3), 179–185.

Ring pessary in situ | Iglesia, C. B., & Smithling, K. R. (2017). Pelvic Organ Prolapse. American Family Physician, 96(3), 179–185.

Surgical management:

Hysterectomy
Uterine conservation (hysteropexy)
Vaginal obliteration (colpocleisis)
- Highest cure rate and lowest morbidity of any surgical intervention
- For those not desiring any future vaginal intercourse
Reconstructive surgery with vaginal apex suspended using:
- Native tissue repair (woman’s own tissues and sutures)
- Mesh can be placed abdominally, to suspend the top of the vagina to the sacrum (sacrocolpopexy), or transvaginally (transvaginal mesh).

Summary