Uterine Artery Embolisation
Uterine artery embolisation (embolization) for fibroids is a relatively
new procedure first carried out in France in a small number of cases in
the early 90s (1). Since then there have been a number of publications
on the technique (2-18). The procedure which is non surgical involves
the occlusion of blood vessels supplying uterine fibroids.
Procedure
Fibroid embolisation is carried out by an Interventional Radiologist
and is technically demanding, requiring significant experience in the technique.
Under local anaesthesia and intravenous sedation a tiny catheter is
inserted under local anaesthetic into an artery in the right groin.
Under X-ray control a micro catheter is introduced selectively into each
of the two arteries that supply the uterus. The micro catheter is passed
approximately half way down the artery and then fine particles of a
solid substance called PVA (Poly Vinyl Alcohol) are injected through the
catheter into the uterine artery. The particles are carried to the leash
of vessels supplying the fibroids. These vessels become silted up
thereby depriving the fibroid of blood which dies and shrinks. PVA is an
inert harmless material which has been used to occlude vessels in other
parts of the body for decades (19).
Following the procedure the patient usually experiences pain over the
next 12 to 24 hours. The pain varies from mild to severe and is
controlled by intravenous and oral analgesics. Occasionally over the
next 1-2 weeks the patient may experience cramps and occasionally some
bleeding and often run a mild intermittent temperature in the first
week. Patients spend 2 days in hospital and are usually advised to take
2 weeks off work. In our series the average time to patients feeling
completely 'normal' was 2.2 weeks. During the procedure intravenous
sedation is administered as required.
The complete process of fibroid shrinkage or in some cases expulsion
takes about 6 to 9 months. However most patients notice a considerable
improvement in their symptoms within 3 months.
Alternatives
Hysterectomy
The commonest surgical treatment for fibroids is hysterectomy.
Approximately 30,000 hysterectomies are carried out for fibroids in the
UK alone and 180,000 in the USA Wallach EE (23). Over the years a large
number of women have obtained considerable benefit from hysterectomy and
in some cases of fibroids it is still the procedure of choice. It is,
however, a major surgical operation usually requiring approximately 5-7
days in hospital and 2-3 months convalescence. Hysterectomy for fibroids
carries a serious complication rate of 4-6% and a mortality of
1:1,000–1,500 (24-25). Serious complications of hysterectomy include
bladder, bowel and ureteric damage, infection, haemorrhage, wound
dehiscence and chronic problems such as bowel dysfunction and bowel
obstruction (26). Most serious complications of hysterectomy require
further major surgery.
Treatments Other Than Hysterectomy or UAE
The medical alternative to hysterectomy is drug treatment with GNRH
analogues such as Zoladex and Synarel but such drugs can only be used
temporarily are only effective on <50% of women and may have unpleasant
side effects. On stopping treatment the fibroids grow back quickly. The usual surgical alternative to hysterectomy is abdominal myomectomy.
In the latter procedure the surgeon attempts to cut out the fibroids
leaving the normal part of the womb intact. Myomectomy has been used
widely for decades but it is a difficult operation with a significant
complication and a high recurrence rate of >70% (30) occurs in patients
with multiple fibroids. A high percentage of
patients having myomectomies will require
re-operation for recurrence usually
hysterectomy. Complications include bowel perforation, damage to
the urinary tract, adhesion formation, infection and haemorrhage. You
should ask your gynaecologist whether he or she feels that abdominal myomectomy would be of benefit in your particular case and likely to
succeed.
Laparoscopic (keyhole surgery) myomectomy is an effective, much less
invasive, procedure but there are major limitations on the size and number of
fibroids that can be treated.
Other recent techniques are MRI guided laser ablation and MRI guided
focussed ultrasound. Essentially both of these techniques cause a burn
within the fibroid which then changes to scar tissue. Only a few
fibroids can be treated at particular sites and the procedure takes
around 2-3
hours. It often only destroys part of the fibroid or fibroids. Only
short term results are available. These would be expected to demonstrate
initial improvement but the concern is that that this will not be
sustained as the residual fibroid tissue regrows. Embolisation has the
advantage of completely destroying all fibroids no matter how numerous
at one session lasting between 45 minutes and one hour. Post-procedure
pain and discharge are probably greater than with MRI ablation but this
is probably because in the latter procedure not all the fibroid tissue is killed.
A recent article in the American Journal of Roentgenology ‘MRI guidance of Focused Ultrasound Therapy of
Uterine Fibroids: Early Results’ 2004;183:1713-1719 showed a mean reduction in fibroid volume at 6 months
of only 13.5% which would normally be regarded as treatment failure. Average for UFE is 60%.
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