RFVTA system offers alternative to myomectomy

Of 232 women enrolled in premarket RFVTA studies – trials in which completing childbearing and continuing contraception were requirements – six conceived at 3.5-15 months post ablation. The number of myomas treated ranged from one to seven and included multiple types and dimensions. Five of these six women delivered full-term healthy babies – one by vaginal delivery and four by cesarean section. The sixth patient had a spontaneous abortion in the first trimester.

Of 43 women who participated in two randomized clinical trials undertaken after FDA clearance, four conceived at 4-23.5 months post ablation. Three of these women had uneventful, full-term pregnancies with vaginal births. The fourth had a cesarean section at 38 weeks.

Considering the theoretical advantages of the Acessa procedure – that it is less damaging to healthy myometrium – and the outcomes reported thus far, it appears likely that Acessa will be preferable to myomectomy. Early results from an ongoing 5-year German study that randomized 50 women to RFVTA or laparoscopic myomectomy show that RFVTA resulted in the treatment of more fibroids and involved a significantly shorter hospital stay and post-operative recovery (Int J Gynaecol Obstet. 2014 Jun;125[3]:261-5).

The technique

The patient is pretreated with a nonsteroidal anti-inflammatory agent and prophylactic antibiotic. She is placed in a supine position with arms tucked, and a single-toothed tenaculum is placed on the cervix from 12 to 6 o’clock, without any instrument for manipulation of the uterus. The system’s dispersive electrode pads are placed symmetrically just above the patella on the anterior thighs; asymmetrical placement could potentially increase the risk of a pad burn.

Two standard laparoscopic ports are placed. A 5-mm trocar for the camera and video laparoscope is placed through the umbilicus or at a supraumbilical or left upper–quadrant level, depending on the patient’s anatomy, her surgical history, and the size of the uterus. A thorough visual inspection of the abdomen should be performed to look for unsuspected findings.

A 10-mm trocar is then placed at the level of the top of the fundus for the intra-abdominal ultrasound probe. Laparoscopic ultrasound is used to survey the entire uterus, map the fibroids, and plan an approach. Once the fibroid to be treated first is identified, the ability to stabilize the uterus accordingly is assessed, and the dimensions of the fibroid are taken. The dimensions will be used by the surgeon with a volume algorithm to calculate the length of ablation time based on the size of the fibroid and electrode deployment.

Under ultrasound guidance, the Acessa radiofrequency ablation handpiece is inserted percutaneously at 12, 3, 6, or 9 o’clock relative to the ultrasound trocar, based on the location of the target fibroid. The uterus must be stabilized, with the handpiece and ultrasound probe parallel and in plane. The handpiece is then inserted 1 cm into the target fibroid through the uterine serosal surface, utilizing a combination of laparoscopic and ultrasound views. Care must be taken to use gentle rotation and minimal downward pressure as the tip of the handpiece is quite sharp.

The location of the tip is confirmed by laparoscopic ultrasound, and the 7-needle electrode array can then be deployed to the ablation site. All three dimensions of the fibroid should be viewed for placement and deployment of the electrodes. Care is taken to avoid large blood vessels and ensure that the electrodes are confined within the fibroid and within the uterus.

Radiofrequency ablation is carried out with a low-voltage, high-frequency alternating current. The radiofrequency waves heat the tissue to an average temperature of 95° C for a length of time determined by a treatment algorithm. The wattage automatically adjusts to maintain the treatment temperature for the calculated duration of ablation.

Small fibroids can be treated in a manual mode without deployment of the electrode array at a current output of 15 W.

At the conclusion of the ablation, the electrodes are withdrawn into the handpiece, the generator is changed to coagulation mode, and the handpiece is slowly withdrawn under ultrasound visualization. The tract is simultaneously coagulated. A bit of additional coagulation is facilitated by pausing at the serosal surface.

Additional fibroids can be ablated through another insertion of the handpiece, either through the same tract or through a new tract.

Larger fibroids may require multiple ablations. The maximum size of ablation is about 5 cm, so it is important to plan the treatment of larger fibroids. This can be accomplished by carefully scanning large fibroids and visualizing the number of overlapping ablations needed to treat the entire volume. I ask my assistant to record the size and location of each ablation; I find this helpful both for organizing the treatment of large fibroids and for dictating the operative report.