Mt training: radiology

Angiography	An x-ray image of blood vessels and heart chambers is obtained after injecting a water-soluble dye through a catheter (tube) into the appropriate blood vessel or heart chamber.
Arteriography	An x-ray image of an artery is obtained after injecting a radiopaque substance directly into the artery. Cerebral arteries are often examined in this manner in a search for aneurysm, blood clot, or tumor.
Arthrography	Dye or air, or both, is injected into a joint, and x-rays are taken of the joint.
Bronchography	An x-ray image of the bronchial tubes after injecting an iodized oil suspension into the bronchi through the trachea.
Cholangiography	Dye is injected intravenously and directed by the liver into bile ducts. This test is frequently ordered after cholecystectomy to examine the patency (size of the opening) of bile ducts.
Cholecystography	A radiopaque substance is given orally; the substance collects in the gallbladder, and x-rays are taken of the gallbladder and the bile ducts. A fatty meal may then be given and follow-up x-rays taken to look for stones in the gallbladder and common bile ducts.
Digital subtraction angiography (DSA)	An x-ray image of contrast-injected blood vessels is produced by taking two x-rays (the first without contrast) and using a computer to subtract obscuring shadows from the image.
Hysterosalpingogr aphy (HSG)	An x-rays record of the uterine tubes is obtained after injecting dye into the uterus via the vagina. The procedure can determine patency of the uterine tubes
Lymhangiography	An x-ray record of lymphatic vessels and nodes is obtained after injection of dye (Ethiodol) into the lymphatic system of the feet or hands.
Myelography	An x-ray of the spinal cord is made after injecting radiopaque dye (Pantopaque) into the subarachnoid space surrounding the spinal cord. This test identifies protrusion of an intervertebral disk or bone pressing on the spinal cord or nerve roots. Tumors in or on the spinal cord can also be identified.
Pyelography	X-ray images are made on the renal pelvis and urinary tract after dye is injected into a vein (intravenous pyelogram) or after dye is injected directly into the urethra, bladder, and ureters (retrograde pyelogram).
Venography	An x-ray image of veins is taken after introducing contrast medium intravenously.

Some individuals experience side effects to the iodine-containing contrast substance. These effects can range from mild reactions such as flushing nausea, warmth, or tingling sensations to fever, life-threatening reactions characterized by airway spasm, hives, laryngeal edema (swelling of the larynx), vasodilation, and tachycardia. Treatment involves immediate establishment of an airway and ventilation followed by injections of epinephrine (adrenaline), corticosteroids, or antihistamines.

1. Fluoroscopy. This x-ray procedure uses a fluorescent screen instead of a photographic plate to derive a visual image from the x-rays that pass through the patient. The fact that ionizing radiation such as x-rays can produce fluorescence (rays of light energy emitted as a result of exposure to and absorption of radiation from another source) is the basis for fluoroscopy. The fluorescent screen glows when it is struck by the x-ray. Opaque tissue, such as bone, appears as a dark shadow image on the fluorescent screen.

A major advantage of the fluoroscopy over normal radiography is that internal organs, such as the heart and digestive tract organs, can be observed in motion. In addition, the patient�s position can be changed constantly to provide the right view at the right time so that the most useful diagnostic information can be obtained.

2. Interventional radiology includes therapeutic procedures that are performed by radiologist while the patient is undergoing fluoroscopy (or ultrasound). Examples of uses of interventional radiology are for placement of drainage catheters, drainage of abscesses, occlusion of bleeding vessels, and installation of antibiotics or chemotherapy through catheters.

Image-intensifier systems for fluoroscopy can brighten fluoroscopic images and can be combined with movie cameras and videotape recorders to obtain a permanent record of either a fluoroscopic or an x-ray examination. This cameras and called cineradiography (cine-means motion).