Radiological and Ultrasound Investigations

Imaging plays a key role in the diagnostic evaluation of women for infertility. It is undertaken after a thorough history taking and clinical examination. The consultant will have come to an opinion of the possible diagnosis and may want a confirmation. The pelvic causes of female infertility are varied and range from tubal, peritubal, uterine and cervical, to ovarian disorders.

Tubal causes:
Tubal block is a major cause of infertility and tubal patency test using hysterosalpingography is the first choice. This is a radiographic procedure where in contrast dye is injected into the uterus and the tubes, then visualised using X rays. Patency of the tubes can be confirmed by spillage of the contrast medium into the peritoneal cavity. Hysterosalpingography also depicts the course, size and contour of the tubes.

The location of the block can also be ascertained. For example, a block at the junction of the tube with the uterus is detected, a recheck can be done after treating for a possible spasm. If it still persists, a recanalization procedure can be undertaken under fluoroscopic guidance.
Blocks at the end distal to the uterus (ampullary end) appear as hydrosalpinx here the contrast material will pool up proximal to the block and there will be no spillage into the peritoneal cavity.
If there is evidence of tubal block due to endometriosis, an MR imaging will be helpful.

Peritubal causes:
Peritubal abnormalities due to adhesions and endometriosis (ectopic uterine tissue) can also be detected. This is reflected by accumulation of abnormal amounts of contrast material adjacent to the ampullary end of the tubes. Besides endometriosis, pelvic inflammatory disease may be another factor. A pelvic MRI is indicated to confirm the peritubal cause. Pelvic ultrasound may detect large endometriosis that have reached the size of a cyst. A laparoscopy will be the final diagnosis if both US and MRI fail to provide a conclusive interpretation.

Uterine causes:
Uterine filling defects and contour abnormalities may be discovered at hysterosalpingography but typically require further characterization with hysterographic or pelvic ultrasonography (US) or pelvic magnetic resonance (MR) imaging.
An ultrasound is a procedure where sound waves are used to image the internal organs of the abdomen and pelvis. It is absolute safe to confirm a pregnancy using ultrasound and is the accepted device of choice among doctors as well as patients. There are three types of US:
Abdominal US
Transvaginal US
Transrectal US

Abdominal US: It is also known as transabdominal US. Structures that are solid and uniform show up well in pelvic ultrasound. Hence, it can detect large masses in the uterus or the ovaries. It can also show up large fluid filled cavities like the urinary bladder. The transducer is a hand held device that is moved over the lower abdomen and the real-time image is seen on the TV screen.
Transvaginal US: Here the transducer is little modified in size and shape so that it can be passed into the female vagina. Besides imaging the pelvic viscera, transvaginal US can be used with additional attachment to take tissue biopsies, to tap fluid and egg from the ovary etc.
Transrectal US: Similarly the US device is modified to pass to the rectum. This is more commonly used in the males to view the prostate and seminal vesicles. Biopsy can also be taken of the tissues using suitable additional instruments.

Pelvic MR
A MRI uses powerful magnets and radio waves to image the interior parts of the human body. Being devoid of X-rays it is much safer. It provides high contrast resolution and can provide slides in any axis which can then be interpreted. However, it is expensive and is used as a second line of investigation if the front line investigations do not provide satisfactory results. MRI should be considered for the evaluation of adnexal pathology when USA characteristics are not definitive to determine whether an adnexal mass is ovarian in origin and to determine the likelihood of malignancy.

Uterine US and MR imaging are used to study the presence, size, and shape of the uterus, in particular the external fundal contour. The presence, location and appearance of the kidneys also should be routinely evaluated because of the high frequency of associated renal anomalies in patients with mullerian duct anomalies. Image acquisition in true coronal and true axial planes of the uterus allows accurate evaluation of the uterine contour and cavity.

Ovarian causes:
Biochemical evaluation throws light on certain functional ovarian disorders like non-functional ovaries, premature ovarian failure, or congenital absence of the ovaries. However, disorders like polycystic ovary syndrome, endometriosis, and ovarian cancer are better diagnosed with radiological and US investigations.

The present trend it to have a multimodal diagnostic approach to investigation of infertility. These investigation provide either a confirmation or a lead for further investigation.