Dye Studies
Traditionally a dye study using a blue coloured substance called Methylene Blue is performed at the time of laparoscopy. This is a quick and simple test where the blue dye is pushed through the cervix and uterus to hopefully pass out the end of the Fallopian tube. This is a fairly reliable test but does have a tendency to lead to a higher than desired false positive diagnosis of Fallopian tube obstruction. More recently Selective Salpingography has been shown to be a more accurate test.
Salpingography
This test is used to assess the outline of the inside of the uterus and whether the fallopian tubes are open. The procedure usually involves passing catheters into each fallopian tube (commonly with hysteroscopic guidance). Having done this, an x-ray machine is used to image where the catheters are, and then x-ray dye is injected into each fallopian tube and the passage of the dye is observed as it passes through the fallopian tube and hopefully out into the abdominal cavity. If this occurs, then the fallopian tube is open. Occasionally abnormalities can be seen along the course of the fallopian tube indicating some form of disease process not causing obstruction. Sometimes a simpler but less accurate method is used (hysterosalpingogram) by attaching a suction cup to the neck of the womb (cervix) and squirting dye in through the cervix and hopefully out into the fallopian tubes.
This method can not diagnose adhesions and has a high rate of false positives. It does not however require a general anaesthetic.
What you have to do
The procedure when carried out for infertility is usually performed at the same time as laparoscopy and hysteroscopy under the same general anaesthetic. Admission to hospital for day surgery is therefore, necessary. The simpler hysterosalpingogram method can be performed alone or in association with pelvic ultrasound as an outpatient,-you can be awake for this procedure.
Benefits & Advantages
Salpingography and laparoscopy are very accurate methods of assessing whether the fallopian tubes are open. Immediate treatment of some causes of fallopian tube obstruction can sometimes be performed at the same time. Hysterosalpingography is safer as it does not involve an anesthetic. However it is also less accurate and problems can not be treated at the same time.
Side effects & Complications
The risks from the procedure are very small indeed. The only identified significant problem is allergic reaction to the iodine-based dye, which is squirted in for x-ray observation. X-rays are used but only for 15 to 30 seconds and therefore they have minimal, if any, problems attached to them. Hysterosalpingography has a small risk of introducing infection (1 in 500 cases).