Prof Saim Yılmaz, MD
"Some uterine fibroids may have additional blood supply from ovarian arteries"
Embolization in difficult cases
In some patients, fibroid embolization is technically more difficult and may require specific methods. For example, in patients with small fibroids or small uterus, the vessels feeding the uterus are thin and it is more difficult to detect these vessels and insert the microcatheter during angiography. In addition, while trying to catheterize these thin vessels, events such as spasm and obstruction may develop easily and embolization may not be possible. In such patients, very thin and soft microcatheters should be preferred whenever possible, drugs that prevent spasm should be used, and the embolization process should be done more slowly and patiently.
In some patients, fibroids may also be fed by vessels of other organs besides the arteries of the uterus. These vessels most commonly originate from the ovarian arteries. In such patients, it must be recognized by the doctor during the embolization that although the uterine arteries are occluded, some parts of the uterus do not seem to be affected and additional feeding vessels (parasitic arteries) must be present. If this is appreciated by an experienced doctor, these parasitic arteries can be investigated and detected with angiography and they can be occluded by embolization in the same session. If this is not done, the embolization process will not be complete and some of the fibroids will remain alive. On the other hand, if the ovarian arteries are to be embolized, this procedure must be done very carefully, because these vessels are more difficult to detect in angiography and it requires more experience to insert a microcatheter and do the embolization.
It must be remembered that if ovarian arteries are to be embolized this may harm the ovaries and decrease the possibility of future pregnancy. Therefore, this point should be discussed with the patient and her husband before any of the ovarian arteries are embolized. If the patient has ovarian feeders of the fibroids but she wants pregnancy, at least one ovarian artery (preferably the one that feeds the fibroids less) should be left intact. Alternatively, the ovarian arteries may not be embolized at all and the fibroids fed by the ovarian arteries may be treated with percutaneous ablation or HIFU.
Embolization should also be done with caution in patients with giant fibroids. In such patients, fibroids die very quickly and easily and liquify. If this liquified tissue drains to the inner surface of the uterus, it can cause a prolonged discharge in the vagina. If it does not, it may accumulate in the body and cause complaints such as prolonged sweating, fatigue, fever, loss of appetite and nausea in the patient. In such patients, embolization should be done less aggressively by using larger particles, if necessary, it should be applied in several sessions, and some special methods should be applied in order to discharge the necrotic uterine fibroid from the vagina.
Some patients may have mild to moderate renal impairment and the contrast medium used during embolization may increase renal impairment. In such patients, the contrast medium should be minimized and the majority of embolization should be performed with saline only. In a normal patient, the contrast agent used during embolization can reach 100-150 ml. If there is kidney failure, this amount should be minimal, preferably not exceeding 10-20 ml. In addition, it will be useful to increase the patient's fluid amount and to give some drugs that protect the kidneys beforehand.
In the patient groups mentioned above, the experience of the physician and his/her team is of great importance in order for the embolization process to be successful and side effects to be minimal.