LLUMC - patient education: basic diagnostic procedures

Patient education

Basic diagnostic procedures

Depending on their specific condition and needs, most patients will undergo certain basic diagnostic tests before, during, and after their hospitalization. These diagnostic evaluations allow the medical and nursing staffs to assess a patient's condition and plan their treatment process. Some of the more frequently utilized tests are described below.


Angiography is a technique for examining the interior of blood vessels by injecting a solution visible on X-rays into them, usually through a catheter, or tube. The passage of the solution can be followed on a television screen at the same time a recording is made on film of the progression of pictures. This record is called an angiogram.


Arthroscopy is the inspection of the interior of a joint through an endoscope (a flexible viewing tube that lights the area).

Cardiac catheterization

Cardiac catheterization is a diagnostic procedure in which a catheter, or tube, is passed along a blood vessel into the heart in order to investigate the heart at work. The procedure is done using a local anesthetic where the catheter is inserted. It is usually virtually painless.


Colonoscopy is used to investigate symptoms and to look for disorders of the colon (the major part of the large intestine). The physician views the inside of the colon with a long, flexible, fiberoptic viewing instrument called a colonoscope.

Computerized Tomography (CT scan, or, "cat scan")

CT scanning is a diagnostic tool that uses x-rays to provide cross-sectional views of the body. Because of the ways x-rays are used and computer processed, CT scanning is able to show organs, arteries, soft tissues, and muscles, and any problems or abnormalities which may be present. The procedure is non-invasive and painless.


Cystoscopy is the examination of the urethra and bladder cavity using long thin viewing tube inserted up the urethra. Diagnostic uses of cystoscopy include inspection of the bladder cavity for stones, tumors, and sites of bleeding and infection, as well as the obtaining of urine samples from each kidney. In addition, by means of injected dye, X-rays can be taken to investigate the site of any obstruction to the flow of urine. Local anesthesia is used for the procedure.

Echocardiogram (Echo)

An echocardiogram is a diagnostic procedure which allows physicians to observe the structure and functioning of the heart without invasive surgery or other more complicated procedures such as a cardiac catheterization. When a patient goes for an echo, a clear, jelly-like substance is applied to the chest. A device that looks somewhat like a plastic knob will then be gently pressed against the chest. This device sends high-frequency sound waves through the body that a computer then uses to produce images of the heart. The procedure is painless and generally takes forty minutes to one hour.

Electrocardiogram (EKG)

An EKG is a simple test in which ten adhesive electrodes are placed on a patient's chest, arms, and legs to measure their heart rate and cardiac functioning. The test is completely painless and generally takes only two to three minutes.

Electroencephalography (EEG)

An EEG is a test that provides important information about the health and function of a person's brain. Small adhesive electrodes are applied to the head which send information back to the EEG machine about the brain's activity and condition. The test is completely painless and usually lasts one and a half hours.

Electromyography (EMG)

EMG is a test in which the electrical activity in muscle is analyzed after being amplified, displayed, and recorded. An EMG can reveal the presence of muscle disorders, or disorders in which the nerve supply to muscle is impaired. The technique for obtaining an EMG is harmless and takes 30 to 60 minutes to perform. Impulses are recorded by attaching small disk electrodes to the skin surface over the muscle or by inserting needle electrodes into the muscle. The electrical activity is evaluated during muscle contraction and at rest.


Laparoscopy is the examination of the inside of the abdomen by means of a laparoscope inserted through a small slit made near the navel. Laparoscopy is done under general anesthetic, and usually involves an overnight stay in the hospital.

Magnetic Resonance Imaging (MRI)

An MRI is an innovative medical procedure in which a large magnet, radio waves, and a computer are used to create precise images of tissues and organs within the body. MRIs can be used to detect brain and nervous system disorders, cardiovascular disease, cancer, organ disease, and musculoskeletal problems. During an MRI, a patient is placed on a magnetic stretcher which is then rolled into a large steel tube. While inside this tube, radio frequency signals are sent through the patient's body (These are not x-rays and are not known to be harmful) that are then "read" be a computer to produce images. The procedure is painless but there are loud grating, whirring, and other machine-like noises inside the MRI chamber. MRI procedures have no known negative risks, but many benefits. They provide detailed images of the inside of the body which allow for early and careful detection of problems.


Mammography is an X-ray procedure for detecting breast cancer at an early stage. Mammography is simple, safe, and causes minimal discomfort. Only low dose X-rays are used. The breast may be X-rayed from above, the side, or both; sometimes an angled view is taken.


Paracentesis is a procedure in which a body cavity is punctured with a needle from the outside. It is most often performed to remove fluid for analysis to aid diagnosis of conditions causing the collection of fluid in the abdominal cavity. The procedure is usually carried out using local anesthesia; it is quick and relatively painless.


Proctoscopy is examination of the anal canal and rectum by means of a proctoscope (a rigid viewing tube) inserted through the anus. The procedure is done without aesthetic. It is uncomfortable, but usually not painful.


Sigmoidoscopy is an office procedure taking less than half an hour and needing no anesthetic. Either a rigid or a flexible viewing tube may be used to examine the rectum and sigmoid colon (the last part of the large intestine). An enema may be used beforehand. The procedure is performed to investigate symptoms such as bleeding from the rectum or lower colon, and to inspect the passage for evidence of disorders such as polyps or cancer.


Diagnostic ultrasounds are used to examine internal sections and organs in the body without x-rays or invasive surgery. When a patient goes for an ultrasound, a clear, jelly-like substance will be applied to the skin over the part of body being examined. A device that looks somewhat like a plastic knob will then be gently pressed against the body. This device sends high-frequency sound waves through the body that a computer then uses to produce images of the body. The procedure is painless and generally takes forty minutes to one hour.

Upper gastrointestinal (GI) series

During an upper GI series test, the patient swallows a special drink (barium sulfate) that shows up on X-rays. Progress of the barium can be followed with a fluoroscope and X-ray pictures can be taken, revealing structures and possible abnormalities of the esophagus, stomach, and duodenum.


Venography is a technique for viewing the interior of a vein by injecting a solution visible on X-rays. Passage of the solution through the vein is recorded on a series of pictures. Venography is used to detect conditions such as deep-vein thrombosis.