Term
| The vast majority of clinical diagnosis come from through these two non-imagery tasks? |
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Definition
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Term
| X-rays are a form of ___________ radiation. |
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Definition
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Term
| Name three imagery methods that use the ionizing radiation. |
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Definition
| radiographic film, CT, nuclear medicine scan |
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Term
| ________ and MRI are examples of imagery modalities that use _________ radiation |
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Definition
| Ultra-sound, non-ionizing |
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Term
| Name the four types of imagery densities and give at least two examples of each. |
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Definition
| air/gas: lungs, gas in intestine; fat: adipose tissue, breasts; soft tissues/water density: blood, solid organs, full bladder; bone & metal: ribs, calcified bones, teeth, metal caps, bullet fragments. |
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Term
| Approximately half of all radiographic studies done are _________ . |
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Definition
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Term
| Chest x-rays are taken in which 2 views and why? |
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Definition
| PA & lateral. To better localize any density that may found on the films. |
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Term
| Name at least three methods/substances film radiography uses to enhance the images. |
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Definition
| Contrast iodine solution - angiogram; barium swallow/enema - GI series; Technetium-99M - nuclear bone scan. |
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Term
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Definition
| An iodine solution is introduced into a vessel (artery or vein) by a catheter. Film Xray and/or CT are taken at timed intervals. The Iodine metal absorbs xrays rendering a radiopacity (white on negative film) at the location of the iodine - hopefully enhancing the vessels of interest. |
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Term
| What is the advantage of CT over classical film imagery? |
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Definition
| 3D rendering of large anatomical regions with increased resolution of soft tissues, also especially good for visualizing fine bone structure. |
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Term
| What methods are used to enhance CT imagery? |
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Definition
| oral, intravenous or intra-arterial contrast material. |
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Term
| Describe what is found on a normal nuclear medicine bone scan. |
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Definition
| Bone is a living tissue and is constantly being remodeled so a light background of tracer deposition is normal over all the bones of the skeleton. In areas of high impact and constant movement such as joints a greater amount of deposition of tracer is seen. Tracer is also excreted from the kidney so the kidneys and urinary bladder also shows "normal" enhancement on bone scan. |
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Term
| What processes would you expect to show enhanced uptake of tracer on nuclear bone scan? |
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Definition
| Deposition of tracer at the site of increased metabolic activity and osteoblast activity (rapid turnover and formation of new bone). This is found at sites of metastatic lesions of the bone and at sites of bone healing after injury. |
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Term
| What is the advantages/limitations of US? |
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Definition
| advantages: no exposure to ionizing radiation, relatively fast, inexpensive and reliable for screening purposes. disadvantages: less resolution than CT, limited use on areas not blocked by bone or having to discern objects filled with or surrounded by air. |
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Term
| What are some indications for the use of MRI? |
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Definition
| brain disease such as infarction & tumors, body cavity tumors, soft tissue injuries that produce edema, spinal cord injuries. |
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Term
| What are some contraindications for MRI? |
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Definition
| ferrous containing objects such as metal surgical staples & aneurysm clips, pace makers, implanted medication pumps, some IUDs, nerve stimulator devices. |
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Term
| On T1 weighted MRI what tissue in general is displayed as bright white? |
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Definition
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Term
| CSF and edema are best visualized as enhanced signal (bright white) using ______ weighted MRI. |
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Definition
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Term
| The subspecialty of modern imagery that can directly treats disease through minimally invasive percutaneous access to internal structures is ____________ radiology. |
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Definition
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