Cancers diagnosed: Breast, thyroid, testicular, uterine, ovarian, prostate, renal (kidney), bladder, gallbladder, liver, spleen, and pancreatic cancers; cancers associated with pregnancy, such as gestational trophoblastic disease; unsuspected adenopathy often detected as an incidental finding during ultrasound examination, especially during examination of the thyroid, breast, and abdomen
Why performed: Ultrasound is used to diagnose primary cancers, both benign and malignant, as well as secondary cancers (also known as metastases). It is also used to diagnose ailments depending on the patient’s symptoms, including but not limited to the following: right-upper-quadrant abdominal pain caused by acute and chronic cholecystitis (both calculus and acalculus) and postoperative leaks following cholecystectomy (gallbladder and right-upper-quadrant ultrasound); goiter, Hashimoto’s thyroiditis, and ectopic parathyroid (thyroid ultrasound); mastitis and Paget disease of the breast (breast ultrasound); pain in the right lower quadrant of the abdomen caused by appendicitis (ultrasound of the appendix); scrotal pain caused by testicular torsion, testicular trauma, orchitis, epididymitis, and hydrocele, as well as undescended testes (testicular ultrasound); pain in the back caused by kidney stones, kidney obstruction, or infection (renal ultrasound); pain and swelling in the legs caused by deep venous thrombosis (DVT study); pain in the epigastric area caused by pancreatitis (abdominal ultrasound); pain in the left upper abdomen caused by splenic infarct or splenic trauma (abdominal ultrasound); pain in the right upper quadrant caused by liver trauma, liver infection, or liver cysts and evaluation for the presence of ascites (abdominal ultrasound); valvular heart disease (cardiac ultrasound or echocardiography); atherosclerosis of the lower-extremity arteries, abdominal aortic aneurysm, and carotid artery atherosclerosis (vascular or arterial Doppler ultrasound); and polycystic ovarian syndrome or pelvic pain and/or bleeding caused by ovarian torsion, uterine polyps, uterine fibroids, and retained products of conception (pelvic and transvaginal ultrasound).
In addition, pregnancy in all three trimesters is evaluated by ultrasound. Ultrasound is also useful in guiding amniocentesis for evaluation of possible fetal anomalies such as Down syndrome (trisomy 21) involving sampling of fluid surrounding the fetus; sampling and removal of fluid from various body cavities in the adult, such as the lung (pleural effusion tap) and abdominal cavity (ascites); and guiding biopsy of various organs in the adult, such as liver, breast, thyroid, and kidney.
Patient preparation: Patients are asked to fast at least four to eight hours prior to gallbladder ultrasound, as food causes the gallbladder to contract and minimizes the area visible for the ultrasound evaluation. Patients are asked to drink at least four glasses of water at least one half hour prior to pelvic ultrasound in order to distend the bladder, which acts as an acoustic window for the study (sound travels well through water). This enables the sonographer, usually a technologist, to evaluate the baby and the womb during pregnancy and to evaluate the state of the uterus, cervix, and ovaries in both the pregnant and the nonpregnant state.
Steps of the procedure: The patient is placed on the back on a table, and the technologist and/or the radiologist applies a clear, water-based conducting gel to the skin over the organ or body part of interest. The gel helps in the transmission of sound waves and may feel wet and cold. The sonographer then rubs a handheld probe or transducer across the surface of the organ of interest. There will be some discomfort from pressure on a full bladder, but the ultrasound waves themselves are painless. Some transducers are designed to be inserted inside a body cavity, such as a transvaginal probe or transrectal probe, which may feel uncomfortable.
After the procedure: The scan is generated by the computer attached to the ultrasound probe and read by the radiologist the same day. The patient will need to contact his or her doctor or health care provider for the radiology report and for follow-up therapy.
Risks: The study is painless and relatively harmless, as no radiation is involved; transvaginal ultrasound is generally done early in a pregnancy to determine fetal age or to detect a suspected ectopic pregnancy. Use of the transvaginal probe late in pregnancy is a decision made by the health care provider, not the sonographer or radiologist.
Results: The results are dependent on the type of scan performed and the reason for the study. Some ultrasound tests are screening tests and may be normal, while others are ordered by a health care provider when an abnormality is suspected.
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