2 The procedure
2.1.1 Falloposcopy with coaxial catheter is used to investigate and treat subfertility in women.
2.1.2 Conventional investigation of subfertility in women often includes examination of the fallopian tubes using hysterosalpingography, or laparoscopy with dye injection, to check the patency of the fallopian tubes. Occasionally, salpingoscopy is performed – this involves inspection of the inside of the fallopian tubes from the outer fimbrial end during laparoscopy or laparotomy.
2.2.1 Falloposcopy with coaxial catheter is a technique for direct inspection of the inside of the fallopian tubes via the cervix and uterus. The coaxial technique involves inserting a narrow catheter over a guidewire through the cervix and uterine cavity into a fallopian tube. The surgeon then passes an endoscope through the catheter. Unlike X-ray methods or laparoscopy, falloposcopy allows balloon dilatation to be performed on obstructive lesions at the time of the procedure.
2.3.1 No controlled studies were found, and none of the studies identified were of high quality. Some studies were on the investigative use of falloposcopy with coaxial catheter and others looked at the procedure as a therapeutic technique.
2.3.2 Among the studies on investigation, the rate of successful fallopian tube cannulation/catheterisation ranged from 83% (30/36) to 85% (110/130). In two studies, the failure rate of falloposcopy was 11% (9/84 and 8/71), but some women may have been included in both studies. Successful imaging or 'correct' visualisation of the fallopian tube ranged from 30% (33/110) to 88% (28/32).
2.3.3 One of the studies on the procedure's therapeutic use found coaxial falloposcopy with direct balloon tuboplasty to be successful in treating endotubal lesions in 41% (13/32) of tubes. Another study reported 96% (52/54) of recanalisations to be technically successful, but of the tubes successfully recanalised, only 31% (16/52) were as a result of falloposcopy with coaxial catheter (the other 36 were treated by selective salpingography). Five pregnancies occurred in this study, but it was not possible to determine whether these occurred in women who underwent falloposcopy with coaxial catheter.
2.3.4 One comparative study on the consistency between the results of hysterosalpingography and falloposcopy was identified. In this study, only 15% (3/20) of tubes found to be blocked when using hysterosalpingography were found to be blocked when using falloposcopy. However, no 'gold standard' test was available to determine the validity of the results. For more details, refer to the 'Sources of evidence' section.
2.3.5 One Specialist Advisor noted that the images obtained by falloposcopy with coaxial catheter were often of poor quality and the 'normal' internal appearance of the tube was not clearly defined.
2.4.1 In the studies identified, the main complications reported were: tubal perforation, which occurred in 1% (1/130) to 4% (3/67) of tubes; and uterine perforation, which occurred during procedures on 2% (3/130) of tubes. One study reported a complication rate of 23% (3/13) for distal fallopian tube obstructions, but it was not clear whether these women had undergone falloposcopy with coaxial catheter. For more details, refer to the 'Sources of evidence' section.
2.4.2 One Specialist Advisor considered the main potential adverse effect of this procedure to be perforation of the fallopian tube; this is usually a minor complication.