Background: The aim of this study was to assess the diagnostic accuracy of three-dimensional ultrasound (3D-US) for determining the position of Essure microinserts and the success of sterilization by the Essure method.
Methods: This retrospective observational study examined the case records of 311 women who underwent hysteroscopic sterilization from October 2002 through October 2008. Imaging with 3D-US or pelvic X-radiography or both was performed 3 months after the procedure to verify device position. Hysterosalpingography (HSG) was performed when a bilateral procedure was not completed because of a history of salpingectomy or blocked tube, when doubt persisted after 3D-US or pelvic radiography, or for comparative purposes in a prospective study. The positions seen on 3D-US were classified in four categories according to a specific scale we devised.
Results: The insertion procedure was completed in 94.2% patients. Only 90.5% underwent imaging verification of the device 3 months afterwards. In all, 227 3D-US, 175 pelvic radiography and 64 HSG imaging procedures were performed. Visualization of the device was possible in 99.6% of the 3D-US images. According to our classification, 3D-US was appropriate for assessing device position for 195 (85.9%) patients. The need for HSG confirmation was significantly lower with 3D-US than radiographic imaging (14.1 versus 26.8%, P = 0.001). 3D-US examinations, compared with the results of HSG as the reference test, had a sensitivity of 100% and a specificity of 76.6%. Neither pregnancy nor early expulsion occurred when 3D-US found that the devices were correctly placed.
Conclusions: 3D-US is a simple technique for assessing the position of Essure(®) microinserts, even after concomitant endometrial surgery. The 3D-US classification presented here appears to make it possible to use HSG for back-up confirmation only when the microinsert is found in a very distal position on 3D-US and thus to protect the majority of women from the negative effects of pelvic radiography and HSG.