Introduction
Ovarian vein incompetence is a common cause of pelvic pain and varicose veins in women, particularly those who have had children. Over the past 12 years Southern Sydney Angiography has successfully performed more than 800 ovarian vein embolisations. Patient satisfaction with this minimally invasive procedure is high.
Anatomy
There is one ovarian vein on each side. They are designed to return blood from the ovaries back up to the heart. The flow should be upward. Reversal of flow due to gravity in the upright position is prevented by a valve at the top of each vein. If the valve becomes incompetent (leaky) then blood can regurgitate from the kidney regions down into the pelvis. This places undue pressure on the veins in the pelvis and causes internal varicose veins. The incompetence is often caused by previous pregnancies when the baby compresses the ovarian veins, sometimes leading to valve failure.
Cause
The veins in the body are the low-pressure component of the cardiovascular system. Whereas arterial pressure averages 120/80 mmHg pressure (120 when the heart beats and 80 in between beats) the veins operate at 5-10mmHg. This low pressure, of itself, is insufficient to overcome gravity in the upright position. Valves are essential for normal vein function by ensuring that blood only flows in the correct direction – back to the heart- rather than falling back down, from the kidney, into the pelvis. The blood from the left ovary drains up to the left kidney vein via the left ovarian vein. The right ovarian vein does not drain into the kidney vein but into the inferior vena cava, the largest vein in the body. The failure of the valve at the junction of the left ovarian vein and the left kidney vein is the commonest cause of pelvic venous congestion. If this valve becomes leaky then blood from the left kidney will leak back down from the kidney and into the pelvis causing swelling of pelvic veins into internal varicose veins. This can, in turn, cause varicose veins in the vulva and contribute to varicose veins in the leg. It can also cause the pelvic venous congestion syndrome – a cause of pelvic pain.
Diagnosis
The diagnosis of ovarian vein incompetence is made by ultrasound measurement of the ovarian vein. If either vein measures more than 6-8mm in diameter it may be incompetent. Ultrasound can visualize reversal of flow in the vein – which confirms incompetence. Pelvic venous congestion can cause a nagging ache in the pelvis or loin particularly toward the end of the day, and sometimes leg pain. It can result in a feeling of the need to pass urine frequently (enlarged veins sitting on the bladder). The incompetence can cause vulval varicose veins and can exacerbate varicose veins in the legs by leaking down into the thighs – causing or worsening varicose veins.
Embolization
A common technique to treat ovarian vein incompetence is ovarian vein embolization. The procedure is performed under conscious sedation. An injection of sedative into the veins causes the patient to be very relaxed and without a care in the world. The procedure is painless and the sedative abolishes any anxiety to render the procedure a pleasant experience.
After local anesthetic, the skin is punctured with a needle and then a very thin plastic tube called a “catheter” is passed into the body. The thin tube is only 1mm in diameter and the patient cannot feel it. The entry point is a vein at the side of the neck or at the top of the leg, depending on patient preference. Both are safe and equally comfortable. The catheter is passed into the ovarian vein. The patient cannot feel any of this as there is no touch sensation in the veins. The vein is then blocked with fine metal filaments called coils. Typically, two to four coils are required. Coils are safe and have been in use for over thirty years. They are designed to occlude veins. In addition, a small amount of liquid sclerosant (called “fibrovein”) is injected into the vein which ensures that the vein does not re-open after blockage. Commonly only the left ovarian vein requires embolization. It is normal to have mild pelvic or back pain for up to one week following the procedure but this is not severe and is temporary. Occasionally the right ovarian vein may need embolization as well.
Where does the blood go after the ovarian vein is blocked?
A leaking ovarian vein is not performing any useful function. Blocking it facilitates improved venous drainage from the pelvis. When the ovarian vein is blocked the blood will pass back toward the heart by alternative or “collateral” channels. The ovarian vein is unnecessary and the ovaries drain perfectly well after it is blocked.
What happens after the procedure?
You will be resting in recovery for 1-2 hours until the sedation wears off. You need to arrange transport as you cannot drive home after the sedation. After the procedure drink plenty of fluid. Normal activity can be resumed the following day except that you should avoid strenuous physical activity for 5 days. You may experience mild discomfort in the abdomen and flank for up to 7 days – it is not severe.
Are there any complications with embolization?
Minor complications may occur such as temporary skin discomfort at the entry site, mild back ache and nausea. These symptoms normally resolve within a week.
Who are interventional radiologists?
Interventional radiologists are radiology doctors who have undertaken additional sub-specialty training in Interventional Radiology procedures. Rather than skin incisions as used in traditional surgery, interventional radiology procedures are performed via skin punctures. Because there is no wound there is minimal discomfort or recovery required after the procedure.
Other useful links:
https://www.cirse.org/patients/ir-procedures/embolisation-for-pelvic-congestion-syndrome/