Imaging of mechanical tubal occlusion devices and potential complications

The increasing use of permanent mechanical contraceptive devices has placed growing demands on radiologists. Hysteroscopically placed tubal occlusion devices, in particular, must be evaluated promptly and carefully to verify that they are in a satisfactory location and are functioning effectively. Hysterosalpingography, radiography, ultrasonography, computed tomography, and magnetic resonance imaging all may be useful for this purpose; however, the acquisition and interpretation of images of these devices can be challenging and requires specific knowledge. Verification of tubal occlusion with a hysteroscopically placed device depends heavily on the adequacy of cornual distention with the contrast medium at hysterosalpingography. Some complications of coil (Essure device) placement, such as tubal perforation and device migration, may be clinically occult and their imaging appearances subtle; a high degree of suspicion is needed to detect them at postprocedural imaging. The position of another tubal occlusion device, a radiolucent silicone matrix (Adiana device), is not directly depicted at imaging with x-rays. By contrast, laparoscopically placed locking tubal clips are well depicted at radiography; however, their dislodgement and migration are seldom symptomatic and thus unlikely to be discovered in time to avert pregnancy. The use of any tubal occlusion device is associated with low albeit finite risks of unwanted intrauterine pregnancy, ectopic pregnancy, tubal and uterine perforation, and device migration into the peritoneal cavity. Results of multiple trials show that a substantial percentage of such complications occurred because of image misinterpretation and consequent patient reliance on tubal occlusion alone for contraception. Accurate description and classification of abnormalities in device position or function seen at imaging performed postprocedurally or for other clinical indications will enhance the value of radiologists' contributions to patient care.