Imaging

Imaging test allow doctors to literally take a better look at you and help guide therapy. Some common imaging test in the hospital include:

Basic x-ray – single black/white image, often the first imaging test as relatively fast, inexpensive, and minimal radiation (equivalent to natural radiation exposure of about 10 days)1

CT Scan – also black/white images but many are taken all at once and when stacked together make a single uniform image. Much more advance imaging technique. Cost is 10 times more than an basic x-ray and radiation exposure is 100-200 times more; but overall still very low. IV dye is often used; some people are allergic to this dye, if you are tell your provider.

MRI – (magnetic resonant imaging) – this uses magnets; not radiation or IV dye from CT scan. Gives a more detailed picture of muscles, nerves and tendons then CT scans. Often preferred test for brain or spinal imaging. MRI machines can be cramped in size, if you dislike cramped spaces tell your provider.

Ultrasound – uses sound waves to produce an image. Carries no risk. Depending on body location sometimes the ultrasound probe can cause some discomfort since has to make contact with swollen tissue; but this is usually mild and transient. An echocardiogram is a specific heart ultrasound. Ultrasounds of the legs which look for blood clots or reduction in blood flow are commonly called “dopplers.”

Stress test – a noninvasive test to assess for significant blockages in the coronary arteries. Pictures are taken by a nuclear medicine camera before and after the patient is stress by either running on a treadmill or given medication to race the heart. In general they are 90% accurate in predicting heart blockages. If given chemicals some people will feel flushed. Patients are not permitted to eat the morning before the test (water only); can eat upon return. The test results do not come back until about 5pm in the evening. Negative stress test argue against any significant coronary blockages. Positive test suggest their are blockages in the heart and the cardiologist will often discuss a cardiac catheterization as the next step.

Cardiac catheterization – this is the gold standard for assessing for heart blockages and intervening. The patient is given light sedation and a catheter is introduced into an artery in either the wrist or groin. From there a cardiologist can thread tiny wires into the heart and using IV dye (similar to CT scan dye) illuminating the heart’s arteries under x-ray. If blockages are found a small mesh metal tube (size of a ballpoint pen spring) can be inserted to open the blockages. Some blockages cannot be opened by cath and patients are referred to Cardiothoracic surgery for an evaluation for Coronary Artery Bypass Grafting (CABG). If a stent in placed the patient must take blood thinners; this is mandatory. Generally aspirin (81mg) forever and another blood thinner for at least 1 year (depends on stent). Blood thinners increase the risk of bleeding.  Blood thinners cannot be stopped without exposing the patient to significant risk of a heart attack. If you are prone to bleeding or have had significant bleeding in the past (gastrointestinal bleeding like ulcer or diverticulosis or brain bleeding) be sure to speak with your cardiologist prior to having cath.

Endoscopy (Upper EGD or colonoscopy) – this is were a camera is inserted into the mouth (EGD) or anus (colonoscopy) to look inside the gastrointestinal tract. Sedation is given during both and most patient’s will have no memory of the procedure from the sedation. EGD looks into the esophagus, stomach, and first part of the small intestine. Patients with trouble swallowing, non cardiac chest pain, and gastrointestinal bleeding often undergo an EGD to locate the cause of the problem. Colonoscopy is done both for routine colon cancer screening and for acute conditions of the lower GI tract. You cannot eat prior to either procedure. Colonoscopy requires prep to cleanse the colon of stool to allow the doctor to see the inside. They is notoriously the most unpleasant part as prep causes diarrhea which cleans out the system. EGD does not require prep.

ERCP (Endoscopic Retrograde Cholangiopancreatography) – a specialized type of upper endoscopy use specifically to go into the bile system and remove gallstones in the common bile duct. It is not performed by all gastroenterologist nor at all institutions and sometimes we have to transfer patients to get it.