Radiographic Pathology: Chapter 2
x-rays (1895), ultrasound (1956), CT (1972), MRI (1977), PET (1979), PET/CT &
PET/MRI (2009) correct answers In what order where the medical imaging modalities
discovered? What year?
ultrasonography/sonography correct answers modality that uses high frequency sound
waves that are pulsed into body tissues by use of a probe (the sound echos off the
tissues it is used to form cross-sectional images)
crystals in transducer correct answers device used in ultrasonography that sends and
receives the sound waves
strong echo correct answers type of reflection/echo produced by a water-tissue
interface
weak echo correct answers type of reflection produced by a tissue mass with small
differences in composition
anechoic correct answers term used to describe tissue/structure lacking a signal &
therefore appears dark (i.e. gallbladder)
hyperechoic & hypoechoic correct answers terms used to make comparisons of echo
intensities between adjacent structures
isoechoic correct answers term used to describe two structures that have the same
look even though the tissues are not the same
presence of acoustic barriers (air, bone, & barium) correct answers What are the
disadvantages of using ultrasonography?
accessible, uses no radiation, no associated adverse effects, & is the modality of choice
for pediatric & pregnant patients correct answers What are some advantages of using
ultrasonography?
computed tomography (CT) correct answers modality that produces cross-sectional
tomographic images by using a narrow x-ray beam & calculated attenuation coefficients;
new technology has moved to helical scanning in which the patient is continuously
scanned while moving through the gantry
volume rendering, 3D image reconstruction, virtual imaging correct answers What are
some post-processing capabilities of CT?
helical correct answers spiral continuous motion
, ultra-fast, accessible, & has post processing capabilities correct answers advantages of
computed tomography(CT)
utilizes radiation & possibility of overexposing patients correct answers disadvantages
of computed tomography (CT)
CT number (Hounsfield unit) correct answers number that reflects the attenuation
properties of the anatomic part
0 correct answers CT number (Hounsfield unit) of water
gray correct answers appearance of water on a CT scan
+1000 correct answers CT number (Hounsfield unit) of bone; highest CT number
possible
white correct answers appearance of bone on a CT scan
-1000 correct answers CT number (Hounsfield unit) of air; lowest CT number possible
true correct answers (true//false) Fat has a CT number less than 0.
true correct answers (true//false) Soft tissues have a CT number higher than 0.
magnetic resonance imaging(MRI) correct answers modality that uses a power magnet
& radiofrequency pulses to generate images of the body
axial, coronal, sagittal correct answers 3 planes an MRI patient can be imaged
relaxation correct answers term given to when protons begin to release to transfer their
absorbed energy as they move back to a low-energy state
T1 & T2 correct answers two types of relaxation that occur simultaneously
receiver coil correct answers listening device that's placed near that anatomic site
detects & calculates the time it takes for both the T1 & T2 relaxation types
high signal intensity correct answers term given to substances or anatomical parts that
appear white on an MRI image
low signal intensity correct answers term given to substances or anatomical parts that
appear dark on an MRI image
x-rays (1895), ultrasound (1956), CT (1972), MRI (1977), PET (1979), PET/CT &
PET/MRI (2009) correct answers In what order where the medical imaging modalities
discovered? What year?
ultrasonography/sonography correct answers modality that uses high frequency sound
waves that are pulsed into body tissues by use of a probe (the sound echos off the
tissues it is used to form cross-sectional images)
crystals in transducer correct answers device used in ultrasonography that sends and
receives the sound waves
strong echo correct answers type of reflection/echo produced by a water-tissue
interface
weak echo correct answers type of reflection produced by a tissue mass with small
differences in composition
anechoic correct answers term used to describe tissue/structure lacking a signal &
therefore appears dark (i.e. gallbladder)
hyperechoic & hypoechoic correct answers terms used to make comparisons of echo
intensities between adjacent structures
isoechoic correct answers term used to describe two structures that have the same
look even though the tissues are not the same
presence of acoustic barriers (air, bone, & barium) correct answers What are the
disadvantages of using ultrasonography?
accessible, uses no radiation, no associated adverse effects, & is the modality of choice
for pediatric & pregnant patients correct answers What are some advantages of using
ultrasonography?
computed tomography (CT) correct answers modality that produces cross-sectional
tomographic images by using a narrow x-ray beam & calculated attenuation coefficients;
new technology has moved to helical scanning in which the patient is continuously
scanned while moving through the gantry
volume rendering, 3D image reconstruction, virtual imaging correct answers What are
some post-processing capabilities of CT?
helical correct answers spiral continuous motion
, ultra-fast, accessible, & has post processing capabilities correct answers advantages of
computed tomography(CT)
utilizes radiation & possibility of overexposing patients correct answers disadvantages
of computed tomography (CT)
CT number (Hounsfield unit) correct answers number that reflects the attenuation
properties of the anatomic part
0 correct answers CT number (Hounsfield unit) of water
gray correct answers appearance of water on a CT scan
+1000 correct answers CT number (Hounsfield unit) of bone; highest CT number
possible
white correct answers appearance of bone on a CT scan
-1000 correct answers CT number (Hounsfield unit) of air; lowest CT number possible
true correct answers (true//false) Fat has a CT number less than 0.
true correct answers (true//false) Soft tissues have a CT number higher than 0.
magnetic resonance imaging(MRI) correct answers modality that uses a power magnet
& radiofrequency pulses to generate images of the body
axial, coronal, sagittal correct answers 3 planes an MRI patient can be imaged
relaxation correct answers term given to when protons begin to release to transfer their
absorbed energy as they move back to a low-energy state
T1 & T2 correct answers two types of relaxation that occur simultaneously
receiver coil correct answers listening device that's placed near that anatomic site
detects & calculates the time it takes for both the T1 & T2 relaxation types
high signal intensity correct answers term given to substances or anatomical parts that
appear white on an MRI image
low signal intensity correct answers term given to substances or anatomical parts that
appear dark on an MRI image
