OTHER DIAGNOSTIC PROCEDURES
Many diagnostic procedures are helpful in evaluating pelvic con-ditions. These may include x-rays, barium enemas, gastrointesti-nal x-ray series, intravenous urography, and cystography studies. Additionally, because the uterus, ovaries, and fallopian tubes are near the kidneys, ureters, and bladder, urologic diagnostic stud-ies, such as the KUB (kidney, ureter, and bladder) and pyelogra-phy are used, as are angiography and radioisotope scanning, if needed. Other diagnostic procedures include hysterosalpingog-raphy and computed tomography (CT) scanning.
Hysterosalpingography is an x-ray study of the uterus and the fal-lopian tubes after injection of a contrast agent. The diagnostic procedure is performed to evaluate infertility or tubal patency and to detect any abnormal condition in the uterine cavity. Some-times the procedure is therapeutic because the flowing contrast agent flushes debris or loosens adhesions.
In preparation for hysterosalpingography, the intestinal tract is cleansed with cathartics and an enema so that gas shadows do not distort the x-ray findings. An analgesic agent may be pre-scribed. The patient is placed in the lithotomy position and the cervix is exposed with a bivalved speculum. A cannula is inserted into the cervix and the contrast agent is injected into the uterine cavity and the fallopian tubes. X-rays are taken to show the path and the distribution of the contrast agent.
Some patients experience nausea, vomiting, cramps, and faintness. After the test, the patient is advised to wear a perineal pad for several hours because the radiopaque agent may stain clothing.
CT scanning has several advantages over ultrasonography (de-scribed below), even though it involves radiation exposure and is more costly. It is more effective than ultrasonography for obese patients or patients with a distended bowel. A CT scan can also demonstrate a tumor and any extension into the retroperitoneal lymph nodes and skeletal tissue, although it has limited value in diagnosing other gynecologic abnormalities.
Ultrasonography (or ultrasound) is a useful adjunct to the phys-ical examination, particularly in the obstetric patient or the pa-tient with abnormal pelvic examination findings. It is a simple procedure based on sound wave transmission that uses pulsed ultrasonic waves at frequencies exceeding 20,000 Hz (formerly cycles per second). A transducer placed in contact with the ab-domen (abdominal scan) or a vaginal probe (vaginal ultrasound) converts mechanical energy into electrical impulses, which in turn are amplified and recorded on an oscilloscope screen while a photograph or video recording of the patterns is taken. The en-tire procedure takes about 10 minutes and involves no ionizing radiation and no discomfort other than a full bladder, which is nec-essary for good visualization during an abdominal scan. (A vaginal ultrasound or sonogram does not require a full bladder.) Saline may be instilled into the uterus (saline infusion sonogram) to help delineate endometrial polyps or fibroids. Polyps are a frequent be-nign cause of bleeding in older women and can be removed by polypectomy.
Magnetic resonance imaging (MRI) produces patterns that are finer and more definitive than other imaging procedures without exposing the patient to radiation. MRI, however, is more costly.