Uterine artery embolization

Uterine artery embolisation (UAE) is an interventional radiological technique to occlude the arterial supply to the uterus and is performed for various reasons.

Historical aspectsHistory

Uterine artery embolisation has been practised for more than 20 years for controlling haemorrhage following delivery / abortion, in ectopic or cervical pregnancy, gestational trophoblastic disease or carcinoma cervix.

The technique was first reported as an effective intervention for fibroids in 1995 when Ravina et al noted that several women with symptomatic leiomyomata who underwent UAE as a pre-hysterectomy treatment had significant clinical improvement to an extent that hysterectomy was no longer required.

It is now estimated that more than 100,000 UAE procedures may have been performed so far for the treatment of fibroids.

Indications

• intramural fibroids
  • menorrhagia 
  • pelvic pain and pressure symptoms
  • bladder outlet obstruction and hydronephrosis due to ureteric compression
  • fibroids with otherwise undiagnosed infertility
  • as a pre-operative measure for large fibroids
• dysfunctional uterine bleeding
• adenomyosis
• others less common indications include
  • uterine artery pseudoaneurysm(s)
  • uterine AVM: trauma, post curettage
  • if active extravasation of contrast it detected during angiography for another reason (post trauma) 

Patients with fibroids, and their related problems, probably present the largest group who is most able to benefit from percutaneous treatment. Presently people with uterine fibroids traditionally undergo total abdominal, vaginal or laparoscopic assisted hysterectomies around the world. The figure in the United States is about 60,000 hysterectomies per year. In less developed and more populous countries like India, the numbers may be even higher. There is an increasing need for non-invasive or less invasive alternatives for uterine fibroids and dysfunctional bleeding. 

Contraindications

• contraindications to angiography
  • severe anaphylactoid reaction to contrast media
  • uncorrectable coagulopathy 
  • severe renal insufficiency 
• pregnancy
• active pelvic infection
• prior pelvic radiation 
• connective tissue disease
• prior surgery with adhesions (relative)

Procedure

Pre-procedural evaluation

• a thorough evaluation of patients symptoms and signs in consultation with a gynaecologist 
• pelvic ultrasound and MRI
• pap smear and endometrial biopsy
• relevant history of other medical problems
• allergies

Equipment

Catheter selection

Any catheter suitable for contralateral and ipsilateral uterine artery cannulation 

• Robertson uterine catheter (RUC): commonly used selective catheter for pelvic angiography
• Cobra glidecath: can also be used
• right internal mammary catheter: may be used, but less common

If the above mentioned catheters are not available, bilateral common femoral artery puncture is an option for contralateral access to the uterine arteries.

Embolic agents

The type of embolic agent selected will depend on the indication. 

• fibroids
  • PVA (300-350 microns)
  • embospheres
• post-partum haemorrhage or vaginal bleeding
  • gel foam particles
  • coils (occasionally)
  • n-butyl-cyanoacrylate (glue)

Technique

Content required

Peri-procedural care

• IV Fluids
• analgesia
• local anaesthesia 
• anti-emetics
• antibiotics

The IV fluids, analgesia, anti-emetics and antibiotics also need to be continued during post procedure.

Complications

• angiography complications
• post-embolisation syndrome
• uterine artery dissection / rupture

Outcomes 

For vaginal bleeding

• alleviates need for emergency hysterectomy
• resumption of menstruation
• successful pregnancy after UAE for PPH
• unsuspected abnormalities treated during UAE for PPH

For fibroids

• menorrhagia / dysmenorrhoea and metrorrhagia improve in 70-95% of cases
• hospital stay is rarely >48 hours
• patients are often back to work within 10 days
• no post laparotomy complications
• mean uterine volume reduction by 26-59%
• fibroid volume reduction by 40-75% (at the end of 6 months)
• the overall complication rate is at ~10% with major complications at ~1.5%

Current recommendations

• ACOG in 2008 issued guidelines that patient with fibroids can be given an option of UAE
• NICE(UK): in 2007 recommended UAE with surgery as a first line treatment option 

See also

• uterine artery embolisation: MRI assessment