BIEN Final Word Scramble
|
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Question | Answer |
Components of a digital grid | dots, picture elements (pixels) |
Component of each pixel | color/tone of pixel |
Bits in a byte | 8 |
Formula for file size | (Dimensions of picture*bits per pixel)/8 bits per byte |
Spatial Resolution | Ability to depict small details |
Contrast | Difference in grey level value between anatomy of interest and background |
Noise | Variance in grey level value |
What does noise make it hard to do? | depict small structures |
Examples of image artifacts | distortion, streaks |
Phantoms | Measure image quality |
Anthropomorphic | phantoms that model realistic anatomy |
Pinhole camera | One of simplest imaging systems |
Why are objects blurred in real pinhole camera systems | finite sized diameter |
A | distance between object and pinhole |
B | distance between pinhole and image |
D | diameter |
Connection between diameter and blurring | direct relationship as diameter increases blurring increases |
Blurring formula | (D*(a+b))/a |
Magnification factor | b/a |
Why does distortion occur? | The rays at the edge of the object are too steep to fit through the pinhole |
What we need to make image | waves/material that can penetrate and exit body, and interact with different tissues, safe, fast |
Electromagnetic Wave spectrum | cosmic,gamma,x-rays,Ultraviolet,Infrared,Microwaves,TV,MRI,Radio,Electric Power |
Ionizing radiation modalities | X-ray, CT, Nuclear Medicine/PET |
Non-ionizing radiation | Ultrasound, MRI |
Ionizing Radiation | created ions can damage RNA |
How are the ions created? | Photons dislodging electrons |
X-ray Radiography | Beam of x-rays travel through body, attenuation depends on density, resulting image is projection (shadow) of body |
Only imaging modality that doesn’t use electromagnetic radiation | Ultrasound |
Which type of radiation is safer | non-ionizing |
Attenuation of x-ray depends on | tissue depth, density, atomic number |
Clinical applications of x-rays | mammography, broken bones, GI tract, angiography( blood vessel injected with iodine) |
Pros of x-rays | High spatial resolution(.1mm), cheap, fast(real time) |
Cons of x-rays | ionizing radiation, 2D projection (shadow) imaging |
2D projection | 3D projection to 2D image, ex is the fork in the patient or on it |
Tomosynthesis | Series of X-rays acquired over limited projection of angles, provides slices |
Pros of tomosynthesis | relatively fast, cheaper than CT, partial 3D info, high spatial resolution (.5mm) |
Cons of tomosynthesis | more ionizing radiation than x-ray, more expensive than x-ray, partial 3d info |
Computed Tomography (CT) | reconstruct tomographic(cross sectional) images by acquiring x-ray projections at multiple view angles |
Clinical applications of CT | looking at heart and arteries |
Pros of CT | Fast, 3D, high spatial resolution (5mm) |
Cons of CT | lots of ionizing radiation, only measures x-ray attenuation(density) ex)iodine and calcium may look same |
Nuclear Medicine/Positron emission tomography (PET) | radioactive tracers injected into body and travel to specific organs and emit radiation |
Type of radiation emitted in nuclear medicine imaging | gamma rays |
Nuclear medicine provides these images rather than anatomical ones | functional |
What Nuclear medicine/PET images are fused with this to provide functional and anatomical images | CT |
Clinical applications of Nuclear Medicine/ PET | Oncology, looking at heart (coronary artery) |
Pros of Nuclear Medicine/ PET | functional imaging, limitless applications |
Chest CT has 200 times the radiation of | A chest X-ray |
Radiation from 2 chest x-rays equal to | 2 round-trip flights from NY to LA |
Risk induced fatal cancer fr 2 chest x-rays equal to | 1 in million, 6 min in canoe |
Ultrasound is produced by sending | high frequency signals |
Sound waves are not electromagnetic but | acoustic |
transducer | transmits and receives sound waves |
The longer it takes to hear an echo the | farther away the tissue is |
Clinical applications of ultrasound | scan abdomen, obstetrics, breast imaging, liver imaging, cardiovascular imaging |
How ultrasound makes a 3D image | moving transducer around |
Pros of Ultrasound | safe, 3D, inexpensive, realtime |
Cons of Ultrasound | limited spatial resolution, need acoustic window (can't see through bone or air) |
MRI | most recently developed, hydrogen protons are small magnets that cause the magnetic field to precess |
Presence of field effect on magnetization | in absence no net,in presence net |
What protons do when placed in external magnetic field | precess about field at Lamour frequency |
Clinical applications of MRI | brain imaging, knee and skeletal imaging, spine injuries, FMRI (Functional MRI sees what part of brain in doing most activity) |
Pros of MRI | great soft tissue contrast, nonionizing radiation, limitless contrast possibilities |
Cons of MRI | Slow, can't image people with magnetic material, claustrophobic, loud, expensive |
How many shades can human eye perceive | 30 shades of grey |
What do you need to see an image | a window |
window width | range of CT numbers displayed |
window level | center of CT numbers |
Filter that increases blurring but reduces noise | low pass |
high pass | filter that emphasizes edge of image |
Traditional view that radiologists used | 2D axial (slices) |
Total number of slices in 1980 | 25-35 |
Total number of slices in 2005 | 600-4000 |
New visualization methods | advanced 3D visualization, guided navigation, quantitative analysis, computer aided detection |
z project | 2D image that displays at each pixel the brightest grey level from all the reconstructed slides |
How 3D info is displayed on 2D image using 3D volume | rendering |
Help radiologists find suspicious regions inn mamography and chest x rays | computer aided detection |
Medical imaging is broken down into | Clinical need, acquiring data, reconstructing image, image processing, image display, clinical evaluation |
Dr. Goldberg | Used imaging as design and planning tool, surgical planning and custom implants, can "rehearse" outside of patient |
Dr. Ladisa | fluid dynamics, angiography, CT, MRI, Ultrasound, investigated cardiovascular disease, made valves as physiological as possible |
Ryan McKindles | Neuromechanics,diffusion tensor imaging |
Diffusion tensor imaging | Ryan McKindles, used to determine spinal injury location, aid in prognosis and monitor drug treatments |
Relationship between bit depth and color | the greater the bit depth the more color in the image |
Christian o Connor | WIFY, know importance of evaluating your skills, be open to opportunities and utilize them, embrace winded and varied career path |
Obtained from converting customer needs into quantitative measurable design specifications | Target specifications |
Things you need to know when solving BME challenge problem | customer needs, target specifications, |
Concept generation | brainstorming and comparing ideas |
phantom construction | final drawing, bill and test plan for validation |
validation | Used imageJ, evaluate based on target specifications |
4 sections of resume | Personal contact info, education, experience, activities/interests |
magnification (again) | aperture to screen distance/ aperture to object distance |
Diameter formula | .047(f)^1/2 where f is optimal focal length |
Field of View formula | di/do=hi/ho where o is object, i is image, d distance, h height |
Created by:
600042666
Popular Medical sets