p.1
Limitations of Plain X-ray Imaging
What are the limitations of plain X-ray imaging?
Plain X-ray imaging has limited detection ability with poor resolution and can't evaluate deeper soft structures very well due to superimposition.
p.5
Differences Between X-ray and CT Imaging
How are the images produced in CT scanning different from those in plain X-ray imaging?
CT scanning reconstructs multiple, two-dimensional, cross-sectional images.
p.11
CT Imaging Techniques and Terminology
What does MPR stand for in medical imaging?
Multiplanar Reconstructions.
p.13
Differences Between X-ray and CT Imaging
What is one advantage of CT imaging over traditional X-rays in terms of structure visualization?
No superimposition of structures.
p.13
Differences Between X-ray and CT Imaging
What is a key advantage of CT imaging in terms of contrast resolution?
CT imaging has better contrast resolution.
p.13
Differences Between X-ray and CT Imaging
What advanced imaging technique does CT offer that traditional X-rays do not?
Multiplanar reformations.
p.3
Applications of Skull and Spine X-rays
How can spine X-rays be used in the context of trauma?
They can help identify fractures, dislocations, and other injuries to the spine.
p.7
CT Imaging Techniques and Terminology
How does CT imaging work?
CT imaging works by using ionizing radiation to create image slices of the body, which are then used to produce cross-sectional images.
p.7
CT Imaging Techniques and Terminology
What kind of images does CT produce?
CT produces cross-sectional images.
p.10
CT Imaging Techniques and Terminology
What is the axial (transverse) plane?
A horizontal plane that passes through the body, dividing it into superior and inferior portions.
p.13
Differences Between X-ray and CT Imaging
What capability does CT imaging have that allows it to measure subtle differences?
CT imaging can measure subtle density differences.
p.14
Computed Tomography (CT) Overview
What are the strengths of CT imaging in terms of bone detail?
CT imaging provides excellent bone detail.
p.14
Computed Tomography (CT) Overview
What is a weight limitation for CT imaging?
CT imaging has a weight limitation of 160 kg.
p.15
Advantages and Limitations of MRI
What are the advantages of MRI over other imaging techniques?
MRI provides superior contrast between different soft tissues, does not use ionizing radiation, and can produce images in multiple planes.
p.15
Advantages and Limitations of MRI
What are some limitations of MRI?
MRI can be expensive, time-consuming, and is not suitable for patients with certain implants or claustrophobia.
p.2
Applications of Skull and Spine X-rays
What are the primary uses of skull X-rays?
Detection of foreign bodies, fractures for medico-legal purposes, and sinusitis.
p.3
Applications of Skull and Spine X-rays
What are the primary applications of spine X-rays?
Trauma, neoplasm, infection, and degenerative disease.
p.10
CT Imaging Techniques and Terminology
What is the coronal plane?
A vertical plane that passes through the body, dividing it into anterior (ventral) and posterior (dorsal) portions.
p.9
CT Imaging Techniques and Terminology
What does 'isodense' mean in the context of CT imaging?
An abnormality that is the same density as the reference structure.
p.9
CT Imaging Techniques and Terminology
What does 'hyperdense' indicate about an abnormality on a CT scan?
It is more dense and appears bright (white).
p.12
CT Imaging Techniques and Terminology
What is Virtual Colonoscopy?
A non-invasive imaging procedure that uses CT scans to create a detailed view of the colon and rectum.
p.16
Magnetic Resonance Imaging (MRI) Principles
What elements make up 99% of the average human body?
Hydrogen (H), Oxygen (O2), and Carbon (C)
p.14
Computed Tomography (CT) Overview
How does the cost of CT imaging compare to MRI?
CT imaging is less expensive than MRI.
p.15
Safety Considerations in MRI Procedures
What safety considerations are important in MRI procedures?
Patients must remove all metal objects, and those with certain implants (like pacemakers) may not be able to undergo MRI. The strong magnetic field can also pose risks.
p.22
MRI Signal Intensity and Interpretation
What determines the signals sent out by different protons in MRI?
The type of tissue the proton is found in.
p.22
MRI Signal Intensity and Interpretation
What is an example of how different protons emit different signals in MRI?
A proton found in bone will emit a very different radio wave signal compared to a proton found in blood.
p.24
MRI Signal Intensity and Interpretation
What is an MRI pulse sequence?
A programmed set of changing magnetic gradients.
p.25
MRI Signal Intensity and Interpretation
What should be assessed to interpret MR images?
The signal intensity of the structure or lesion in both T1WI and T2WI.
p.33
Advantages and Limitations of MRI
Why is MRI considered an expensive imaging technique?
Due to the high cost of the equipment and operation.
p.27
MRI Signal Intensity and Interpretation
What is the MRI appearance of a chronic hematoma on T1-weighted imaging (T1WI)?
Isointense (Iso) or Hypointense (Hypo)
p.3
Applications of Skull and Spine X-rays
How are spine X-rays useful in diagnosing infections?
They can reveal signs of infection in the vertebrae or intervertebral discs.
p.10
CT Imaging Techniques and Terminology
What is the sagittal plane?
A vertical plane that passes through the body, dividing it into right and left portions.
p.11
CT Imaging Techniques and Terminology
What types of images can be created using Multiplanar Reconstructions (MPR)?
Coronal, Sagittal, Para-axial, Oblique, and Curved images.
p.13
Differences Between X-ray and CT Imaging
How does CT imaging compare to traditional X-rays in terms of image detail?
CT imaging produces more detailed images of internal organs than traditional X-rays.
p.14
CT Imaging Techniques and Terminology
What capability does CT imaging have in terms of image rendering?
CT imaging can render 3D images.
p.18
Magnetic Resonance Imaging (MRI) Principles
What do protons emit as they move back into their original positions after the magnetic field is switched off?
They send out radio waves of their own as a signal.
p.15
Magnetic Resonance Imaging (MRI) Principles
What are the common uses of MRI?
MRI is commonly used to diagnose and monitor conditions in the brain, spine, joints, and soft tissues.
p.22
MRI Signal Intensity and Interpretation
What is the key concept illustrated by the statement 'Different Protons = Different MRI signals'?
Different tissues or structures emit different MRI signals based on the protons they contain.
p.24
MRI Signal Intensity and Interpretation
How are MRI pulse sequences chosen?
They are chosen to best suit the particular clinical application.
p.25
MRI Signal Intensity and Interpretation
How does cerebrospinal fluid (CSF) appear in T2-weighted imaging (T2WI)?
CSF appears as a high signal, or 'bright' (white).
p.33
Advantages and Limitations of MRI
What is a limitation of MRI for very large individuals?
They may not fit into the MRI machine.
p.38
Differences Between X-ray and CT Imaging
How do dense tissues like bones appear on an X-ray image?
Dense tissues like bones absorb more X-rays and appear white on the X-ray image.
p.5
CT Imaging Techniques and Terminology
What device absorbs penetrated X-rays in CT scanning?
An electronic device called a 'detector array'.
p.5
Differences Between X-ray and CT Imaging
What type of radiation do both X-ray and CT imaging use?
Ionizing radiation from a source.
p.18
Magnetic Resonance Imaging (MRI) Principles
What happens to protons once the magnetic field is switched off in MRI?
The protons begin to lose their alignment and go back to the position they were in before the magnetic field was applied.
p.38
Differences Between X-ray and CT Imaging
What is the primary principle behind X-ray imaging?
X-rays pass through the body and are absorbed at different rates by different tissues, creating an image.
p.5
Limitations of Plain X-ray Imaging
How does plain X-ray imaging absorb penetrated X-rays?
The film directly absorbs penetrated X-rays.
p.8
CT Imaging Techniques and Terminology
What is the CT number used to describe?
The average density of a tissue.
p.12
CT Imaging Techniques and Terminology
What are the benefits of Virtual Colonoscopy over traditional colonoscopy?
Virtual Colonoscopy is less invasive, does not require sedation, and has a lower risk of complications.
p.22
MRI Signal Intensity and Interpretation
How do signal differences in protons help in MRI?
They allow a picture to be created and enable different tissues or structures to be distinguished from one another.
p.26
MRI Signal Intensity and Interpretation
What is the signal intensity of fat (subcutaneous fat, dermoid cyst) in T1 and T2 weighted MRI?
High signal in T1 and low signal in T2.
p.33
Advantages and Limitations of MRI
Why can't MRI be performed on people with certain implanted metal objects?
Because the strong magnetic fields can interfere with or be affected by metal objects like pacemakers and certain implants.
p.33
Advantages and Limitations of MRI
What precaution must be taken due to the noise produced by MRI machines?
Subjects must be given ear plugs.
p.1
Limitations of Plain X-ray Imaging
Why can't plain X-rays evaluate deeper soft structures effectively?
Because of superimposition, which causes poor resolution and limited detection ability.
p.7
Computed Tomography (CT) Overview
What is the purpose of producing image slices in CT?
The purpose is to better view the internal organs of the body.
p.11
CT Imaging Techniques and Terminology
What is the purpose of 3D Volume Rendering?
To provide detailed three-dimensional views of anatomical structures.
p.12
Cerebral Angiography Techniques
What can Cerebral CT Angiography detect?
It can detect abnormalities such as aneurysms, blockages, and other vascular issues in the brain.
p.18
Magnetic Resonance Imaging (MRI) Principles
What role do RF coils play in MRI?
RF coils are used to detect the radio waves emitted by protons as they return to their original positions.
p.26
MRI Signal Intensity and Interpretation
How does subacute blood (met Hb) appear in T1 and T2 weighted MRI?
High signal in both T1 and T2.
p.26
MRI Signal Intensity and Interpretation
How do fluids such as CSF, urine, pleural effusion, and ascites appear in T1 and T2 weighted MRI?
Low signal in T1 and high signal in T2.
p.26
MRI Signal Intensity and Interpretation
How do edema and infarctions appear in T1 and T2 weighted MRI?
Low signal in T1 and high signal in T2.
p.33
Advantages and Limitations of MRI
Why might MRI be challenging for immobile, elderly, or sick patients?
Because the exam can be difficult for them to endure due to the need to remain still for extended periods.
p.38
Differences Between X-ray and CT Imaging
What happens to X-rays that pass through less dense tissues?
X-rays that pass through less dense tissues are not absorbed as much and appear darker on the X-ray image.
p.2
Applications of Skull and Spine X-rays
What type of foreign objects can be detected using skull X-rays?
Various types of foreign bodies.
p.5
CT Imaging Techniques and Terminology
What does the detector array do with the absorbed X-rays in CT scanning?
It measures the X-ray amount and transmits the data to a computer system.
p.12
CT Imaging Techniques and Terminology
What is Virtual Endoscopy?
A non-invasive imaging technique that uses CT or MRI data to create a 3D visualization of the interior of a body part, such as the bronchi or arteries.
p.12
Cerebral Angiography Techniques
What is Cerebral CT Angiography used for?
It is used to visualize the blood vessels in the brain to detect abnormalities such as aneurysms or blockages.
p.14
Computed Tomography (CT) Overview
What is a limitation of CT imaging in terms of radiation?
CT imaging involves exposure to radiation.
p.20
MRI Signal Intensity and Interpretation
What are MRI images based on?
The location and strength of the incoming signals.
p.25
MRI Signal Intensity and Interpretation
What is the primary use of T2-weighted imaging (T2WI) in MRI?
To detect a pathologic process such as edema or swelling.
p.38
Differences Between X-ray and CT Imaging
How do soft tissues appear on an X-ray image?
Soft tissues absorb fewer X-rays and appear in shades of gray on the X-ray image.
p.5
CT Imaging Techniques and Terminology
What role does the computer system play in CT scanning?
It calculates and analyzes data from each detector in each level and reconstructs multiple, two-dimensional, cross-sectional images.
p.10
CT Imaging Techniques and Terminology
What is the oblique plane?
A plane that passes diagonally between the axes of two other planes.
p.9
CT Imaging Techniques and Terminology
What does 'hypodense' indicate about an abnormality on a CT scan?
It is less dense than the reference structure.
p.11
CT Imaging Techniques and Terminology
What is 3D Volume Rendering in medical imaging?
A technique that creates three-dimensional images from CT or MRI scans.
p.15
Magnetic Resonance Imaging (MRI) Principles
What is the primary principle behind MRI?
MRI uses strong magnetic fields and radio waves to generate detailed images of the inside of the body.
p.25
MRI Signal Intensity and Interpretation
How does cerebrospinal fluid (CSF) appear in T1-weighted imaging (T1WI)?
CSF appears as a low signal, or 'dark'.
p.26
MRI Signal Intensity and Interpretation
What is the signal intensity of cortical bone in T1 and T2 weighted MRI?
Low signal in both T1 and T2.
p.33
Advantages and Limitations of MRI
Why might children require sedation during an MRI scan?
To help them remain still and calm during the procedure.
p.3
Applications of Skull and Spine X-rays
What degenerative diseases can be assessed using spine X-rays?
Conditions such as osteoarthritis and degenerative disc disease.
p.7
Computed Tomography (CT) Overview
What is Computed Tomography (CT)?
CT is a modality that uses ionizing radiation to cut the body into image slices, producing cross-sectional images to better view internal organs.
p.7
Computed Tomography (CT) Overview
What type of radiation does CT use?
CT uses ionizing radiation.
p.8
CT Imaging Techniques and Terminology
What is the purpose of using different windows (e.g., Soft Tissue Window, Bone Window) in CT imaging?
To optimize the visualization of different types of tissues.
p.12
Differences Between X-ray and CT Imaging
How does Virtual Endoscopy differ from traditional endoscopy?
Virtual Endoscopy is non-invasive and uses imaging data from CT or MRI, whereas traditional endoscopy involves inserting a scope into the body.
p.14
CT Imaging Techniques and Terminology
What is CT angiography used for?
CT angiography is used for imaging blood vessels with the use of contrast.
p.14
CT Imaging Techniques and Terminology
What is a common issue with CT imaging when metal is present?
CT imaging can produce artifacts when metal is present.
p.15
Magnetic Resonance Imaging (MRI) Principles
What does MRI stand for?
Magnetic Resonance Imaging
p.15
Magnetic Resonance Imaging (MRI) Principles
What type of images does MRI produce?
Detailed images of the inside of the body, particularly soft tissues.
p.24
MRI Signal Intensity and Interpretation
Why are different MRI pulse sequences used?
To allow the radiologist to image the same tissue in various ways and obtain important diagnostic information about the tissue.
p.24
MRI Signal Intensity and Interpretation
What should be followed to differentiate diagnoses of lesions in MRI?
The behavior of the lesions in different pulse sequences.
p.25
MRI Signal Intensity and Interpretation
What common practice should be followed when interpreting MR images?
Follow the well-known common signal behavior.
p.26
MRI Signal Intensity and Interpretation
What is the signal intensity of most tumors in T1 and T2 weighted MRI?
Low signal in T1 and high signal in T2.
p.33
Advantages and Limitations of MRI
How can body movement affect an MRI scan?
It can cause artifacts and reduce the quality of the images.
p.33
Advantages and Limitations of MRI
What is the range of audible noise produced by an MRI machine?
65 - 115 dB, equivalent to the noise level of a jet engine at takeoff.
p.14
Computed Tomography (CT) Overview
How does CT imaging perform in terms of soft tissue contrast?
CT imaging offers good soft tissue contrast.
p.14
CT Imaging Techniques and Terminology
What are some complications associated with the use of contrast in CT imaging?
Contrast complications can occur, but they can be substituted by MRI.
p.20
MRI Signal Intensity and Interpretation
What allows detailed MRI images to be created?
The location and strength of the incoming signals.
p.26
MRI Signal Intensity and Interpretation
How does contrast injection (Gd-DTPA) appear in T1 and T2 weighted MRI?
Low signal in T1 and high signal in T2.
p.38
Applications of Skull and Spine X-rays
Why are X-rays useful in medical imaging?
X-rays are useful because they can create detailed images of the inside of the body, helping to diagnose fractures, infections, and other conditions.
