What are the advantages of kV imaging?
High contrast resolution, excellent for visualising bony anatomy and soft tissue. Low dose. Ideal for daily setup verification.
Q: What are the disadvantages of kV imaging?
A: Limited penetration for deep structures. Poor visibility of dense tissues or prosthetics. Susceptible to scatter in large patients.
Q: What are the advantages of MV imaging?
A: Good penetration for deep or dense anatomy. Useful when kV is unsuitable (e.g. metal implants). Matches treatment beam geometry.
Q: What are the disadvantages of MV imaging?
A: Poor contrast resolution. Higher dose. Less effective for soft tissue visualisation.
Q: What are the advantages of CBCT (Cone Beam CT)?
A: 3D volumetric imaging. Excellent for soft tissue and bony alignment. Enables adaptive planning and anatomical monitoring.
Q: What are the disadvantages of CBCT?
A: Higher imaging dose. Longer acquisition time. Susceptible to motion artefacts and scatter.
Q: What interactions occur in kV imaging?
A: Dominated by the photoelectric effect, enhancing contrast between soft tissues and bone.
Q: What interactions occur in MV imaging?
A: Dominated by Compton scatter, reducing image contrast but allowing deeper penetration.
Q: What interactions occur in CBCT?
A: Combination of photoelectric effect and Compton scatter, depending on energy and tissue type.
📍 Anatomical Landmarks – Q&A Flashcards
Q: What landmarks are used in pelvic imaging?
A: Pubic symphysis, sacrum, iliac crests, femoral heads, bladder, rectum, vaginal vault (for gynae).
Q: What landmarks are used in thorax imaging?
A: Carina, vertebral bodies, sternum, ribs, lung apices, heart borders, diaphragm.
Q: What landmarks are used in breast imaging?
A: Sternum, ribs, lung edge, chest wall, nipple, surgical clips (if present).
Q: What landmarks are used in head and neck imaging?
A: Mandible, cervical vertebrae, hyoid bone, mastoid process, base of skull, spinal canal.
Q: What landmarks are used in neuro imaging?
A: Skull base, ventricles, falx cerebri, brainstem, pituitary fossa, cerebellum.
🧠 Clinical Imaging Practice – Q&A Flashcards
Q: Why are weekly CBCTs taken for head and neck patients?
A: To monitor anatomical changes (e.g. weight loss, tumour shrinkage), ensure accurate dose delivery, and assess need for re-planning.
Q: What must be considered when reviewing a thorax image?
A: Lung inflation, patient breathing phase, heart position, spinal alignment, and reproducibility of setup.
Q: What are fiducials?
A: Small markers (metallic or tattoo) placed internally or externally to aid in precise image-guided localisation of the treatment area.
Q: What is assessed on a pelvic CBCT?
A: Bladder and rectal filling, bony alignment (e.g. pubic symphysis, sacrum), soft tissue structures (e.g. cervix, prostate), and organ motion.
Q: What are the advantages of bladder scanning?
A: Non-invasive, quick, real-time assessment of bladder volume to ensure reproducible setup and reduce dose to surrounding organs.
Q: What are the disadvantages of bladder scanning?
A: Operator-dependent accuracy, limited in obese patients or post-surgical anatomy, may not reflect bladder shape or position.
Q: Why do we bladder scan cervix and endometrium patients?
A: To ensure consistent bladder filling, which stabilises uterus position, reduces bowel dose, and improves reproducibility of pelvic anatomy.
Q: What is the importance of fan type in CBCT imaging (e.g. half fan)?
A: Half fan mode increases field of view for larger anatomy (e.g. pelvis), but may reduce image quality. Full fan offers better resolution but smaller coverage.
Q: Why do we use MV imaging for femur (remur)?
A: MV penetrates dense bone better than kV, especially in prosthetic or large patients. Useful when kV fails to visualise deep femoral anatomy.
Would you like these grouped into printable flashcards or turned into a quiz to test your recall? I can also add diagrams or mnemonics if you want to reinforce tricky concepts visually!
What are the disadvantages of kV imaging?
Limited penetration for deep structures. Poor visibility of dense tissues or prosthetics. Susceptible to scatter in large patients.
What are the advantages of MV imaging?
Good penetration for deep or dense anatomy. Useful when kV is unsuitable (e.g. metal implants). Matches treatment beam geometry.
What are the disadvantages of MV imaging?
Poor contrast resolution. Higher dose. Less effective for soft tissue visualisation.
What are the advantages of CBCT (Cone Beam CT)?
3D volumetric imaging. Excellent for soft tissue and bony alignment. Enables adaptive planning and anatomical monitoring.
What are the disadvantages of CBCT?
Higher imaging dose. Longer acquisition time. Susceptible to motion artefacts and scatter.
What interactions occur in kV imaging?
Dominated by the photoelectric effect, enhancing contrast between soft tissues and bone.
What interactions occur in MV imaging?
Dominated by Compton scatter, reducing image contrast but allowing deeper penetration.
What interactions occur in CBCT?
Combination of photoelectric effect and Compton scatter, depending on energy and tissue type.
What landmarks are used in pelvic imaging?
Pubic symphysis, sacrum, iliac crests, femoral heads, bladder, rectum, vaginal vault (for gynae).
What landmarks are used in thorax imaging?
Carina, vertebral bodies, sternum, ribs, lung apices, heart borders, diaphragm.
What landmarks are used in breast imaging?
Sternum, ribs, lung edge, chest wall, nipple, surgical clips (if present).
What landmarks are used in head and neck imaging?
Mandible, cervical vertebrae, hyoid bone, mastoid process, base of skull, spinal canal.
What landmarks are used in neuro imaging?
Skull base, ventricles, falx cerebri, brainstem, pituitary fossa, cerebellum.
Why are weekly CBCTs taken for head and neck patients?
To monitor anatomical changes (e.g. weight loss, tumour shrinkage), ensure accurate dose delivery, and assess need for re-planning.
What must be considered when reviewing a thorax image?
Lung inflation, patient breathing phase, heart position, spinal alignment, and reproducibility of setup.
What are fiducials?
Small markers (metallic or tattoo) placed internally or externally to aid in precise image-guided localisation of the treatment area.
What is assessed on a pelvic CBCT?
Bladder and rectal filling, bony alignment (e.g. pubic symphysis, sacrum), soft tissue structures (e.g. cervix, prostate), and organ motion.
What are the advantages of bladder scanning?
Non-invasive, quick, real-time assessment of bladder volume to ensure reproducible setup and reduce dose to surrounding organs.
What are the disadvantages of bladder scanning?
Operator-dependent accuracy, limited in obese patients or post-surgical anatomy, may not reflect bladder shape or position
Why do we bladder scan cervix and endometrium patients?
To ensure consistent bladder filling, which stabilises uterus position, reduces bowel dose, and improves reproducibility of pelvic anatomy.
What is the importance of fan type in CBCT imaging (e.g. half fan)?
Half fan mode increases field of view for larger anatomy (e.g. pelvis), but may reduce image quality. Full fan offers better resolution but smaller coverage.
Why do we use MV imaging for femur?
MV penetrates dense bone better than kV, especially in prosthetic or large patients. Useful when kV fails to visualise deep femoral anatomy.
