Microwave ablation of uterus is the method to resolve heavy menstrual bleeding or menorrhagia. Memorrhagia without cause used to be the main reason for having a hysterectomy. From one third up to one half of all hysterectomias could be attributed to hemorrhagia without major pathology, so it would be of great interest to invent a minimally invasive surgical technique to resolve this problem.
The idea of endometrial ablation is to destroy the inner lining of the uterus, since technically speaking, it is the endometrium that produces menstruation if there were no fertilised and implanted egg. Ever since the 1980’s, the race is on and new devices appear every three or four years, especially since 1997/8.
A Short Comparison of Techniques for Endometrial Ablation
The first generation techniques are:
. resection,
. roller-ball and
. laser ablation
and they all require direct visualization of the endometrium using a hysteroscope. The operator must be thoroughly schooled, since all these techniques require great skill and knowledge on his or her behalf.
Newer techniques are, amongst others,
. microwave (explained on this very page that you are reading now) and
. thermal balloon endometrial ablation, as well as
. Novasure.
In theory, they offer a one day out-patient procedure, and should enable the patient to go home the same day (if there were no complications).
The Technology of Microwave Ablation
In microwave ablation, heat is generated through a high frequency microwave energy. The endometrium is being rapidly heated and then destroyed. The frequency of microwave rays is 9GHz and endometrial tissue absorbs it up to the depth of 3mm. The actually destroyed level of tissue is 5-6 mm — more than enough to destroy the endometrium without damaging the other organs.
The applicator is introduced to the uterus through a dilated cervix, and once in, it starts to deliver the microwaves. The operator slowly moves it, making broad sweeping movements so that the whole interior of the womb is under control. The length of the treatment is 10-15 minutes, and some kind of anesthesia must be present.
Whom is Microwave Ablation For?
Microwave endometrial ablation (MEA) is for women who have
. excessive uterine bleeding (menorrhagia), and who
. do not want to have any more children and
. in cases in which it is certain that menorrhagia is not due to some cancerous condition.
Whom Microwave Ablation is Not For?
Microwave ablation may not be used on a patient that
. has undergone any previous endometrial ablation procedure,
. has had the MEA applicator re-inserted following treatment or partial treatment,
. is pregnant,
. wants to become pregnant in the future,
. has had a classical cesarean section childbirth,
. transmural myomectomy or any other anatomic or pathologic condition in which weakness of the myometrium could exist, .has an intrauterine device (IUD) currently in place,
. has Essure contraceptive micro-inserts,
. has undiagnosed vaginal bleeding,
. has a myometrial thickness of less than 10 mm in any area of the uterus,
. has a uterine sounding length less than 6 cm,
. has uterine perforation or wall damage observed or suspected during pre-procedure examination,
. has pre-malignant conditions of the endometrium, such as
. unresolved (atypical) adenomatous hyperplasia (non-cancerous excessive tissue growth),
. has a known or suspected endometrial carcinoma (uterine cancer)
. has undergone mechanical endometrial thinning such as dilation and curettage (D&C) or suction aspiration,
. has an active genital or urinary tract infection at the time of the procedure, or
. has active pelvic inflammatory disease (PID).
Precautions for the Operator
There have been a small number of recorded cases of serious injuries induced by the microwave ablation procedure. Typically, the applicator would burn through the uterus and the intestines, which then lead to further surgeries to repair the damages. In order to minimize the risks, the operator should be obliged to
. ensure that the uterine wall is thick enough for the procedure to work (this means an ultrasound evaluation before the procedure),
. use hysteroscopy (visual inspection) of the inside of the uterus just before the operation,
. train more for the entire procedure, and
. conduct at least three MEA procedures under supervision before being allowed to operate on their own.
If your doctor wants a microwave ablation for you, please ensure that the above rules and procedures are being held in regard.
The Outcome of the Microwave Ablation
In preliminary tests, the success rate of stopping menorrhagia was 87%. This means that menstrual bleeding was reduced to normal levels. For 55% of women in the study, the bleeding was totally stopped.
These results are comparable to other methods of endometrial ablation. For the largest part of participants, all went well; for a small part of patients, the after procedure period was problematic, while for 10-15% of patients, it all ended with this or that type of hysterectomy anyway.
What To Do Next?
For more information on endometrial ablation in general (the general course of reconvalscense after the procedure, symptoms, the outcome of endometrial ablation in general etc.), please visit our main endometrial ablation page.