Doctors diagnose diseases by the primary cause, for example, one type of diarrhea results from dysentery, an infection of the intestines caused by a bacterium. Another type of diarrhea can be caused by Crohn’s disease, an inflammation of the intestines that is not associated with any known infection. A medical diagnosis requires clarification of the primary cause; diarrhea is not a diagnosis, but dysentery and Crohn’s disease are. In a similar way, a disorder of the heart, the thyroid gland, the gallbladder or any other body organ is first classified medically by its cause and by the physical changes it produces. Diagnostic tests can pinpoint the exact cause of a symptom.
Echocardiography and Doppler: Circulatory System
An echocardiogram uses ultrasound waves to visualize the internal structure of the heart and its movements. According to the National Institutes of Medicine (NIH), a transducer is placed on the surface of the chest and directed to various parts of the heart. By moving the transducer, it gives a detailed picture of how the heart is working. Echocardiography is useful in showing abnormalities of the heart valves, such as defects in the mitral or aortic valves, which are particularly prone to disease.
Doppler imaging measures blood flow through the blood vessels. It is accurate and extremely useful when investigating serious or potentially serious problems caused by an inadequate blood supply to the legs or arms because of blood vessel disease. In 95 percent of the cases, Doppler scanning can detect a significant reduction in blood flow.
Pyelography: Urinary System
Intravenous pyelography (IVP), provides X-rays of the urinary system and involves the introduction of an iodine-based contrast medium into the kidneys, ureters and bladder. According to the American Urological Association, this test evaluates for recurrent urinary tract or kidney infections, or the cause of blood in the urine. It can reveal abnormalities, such as kidney tumors or stones or obstruction, anywhere in the urinary system.
Barium: Digestive System
Barium examinations can pinpoint abnormalities in any part of the digestive tract, from the esophagus to the rectum. Before taking the X-ray, the patient either receives an enema containing barium sulfate or swallows a suspension of barium sulfate, a metallic element that is impervious to radiography, allowing it to provide images of the digestive tract. According to The American College of Gastroenterology, barium X-rays are useful in revealing narrowing of the esophagus, swallowing disorders, hiatal hernia, stomach polyps and tumors, ulcers of the stomach, certain intestinal disorders and tumors or polyps in the colon.
Bronchoscopy: Respiratory System
Bronchoscopy helps the doctor identify the cause of a persistent cough or coughing up blood. According to the NIH, a bronchoscopy can also confirm the presence of an inhaled foreign body or a tumor or locate the source of bleeding in the lungs. A physician can scrape the inside of the airway and lung during the bronchoscopy, providing tissue samples to examine for signs of cancer or lung infection.
References
- U.S. National Library of Medicine: Echocardiogram
- RadiologyInfo.org: General Ultrasound Imaging
- American Urological Association Education and Research, UrologyHealth.org: Management of Ureterl Stones
- The American College of Gastroenterology: Diverticular Disease of the Colon
- U.S. National Library of Medicine, Medline Plus: Bronchoscopy
