Non-ionising imaging exam tips

Exam tips

• Apply Ultrasound imaging evidence

  Explain the physics evidence first: identify the medical context, state the relevant quantity or process, then link it directly to Describe generation and detection of ultrasound pulses..

  AQA A-level medical physics answers score better when they connect the clinical situation to a named physical principle, rather than giving a generic medical description.

• Understanding Acoustic Impedance

  To explain reflection at tissue boundaries, remember that reflection occurs when there is a difference in acoustic impedance between two tissues. Use the formula for reflection coefficient: R = (Z2 - Z1)² / (Z2 + Z1)², where Z is the acoustic impedance.

  This helps you understand how ultrasound waves behave at tissue interfaces, which is crucial for interpreting ultrasound imaging results.

• Calculating Depth from Pulse Return Time

  Use the formula: Depth = (Speed of Sound in Tissue × Time) / 2.

  This formula accounts for the time taken for the ultrasound pulse to travel to the boundary and back, allowing you to accurately determine the depth of the tissue.

• Apply Ultrasound imaging evidence

  Explain the physics evidence first: identify the medical context, state the relevant quantity or process, then link it directly to Discuss advantages and limitations of ultrasound imaging..

  AQA A-level medical physics answers score better when they connect the clinical situation to a named physical principle, rather than giving a generic medical description.

• Understanding Total Internal Reflection

  To explain total internal reflection in optical fibres, remember that it occurs when light travels from a denser medium to a less dense medium at an angle greater than the critical angle.

  This understanding is crucial for explaining how optical fibres transmit light efficiently, which is a key concept in medical imaging.

• Understanding Endoscope Functionality

  To describe how endoscopes use fibre optics, remember that light travels through the optical fibres via total internal reflection, allowing for clear image transmission.

  This helps you accurately explain the principle behind endoscopes, which is crucial for understanding their application in medical imaging.

• Apply Fibre optics and endoscopy evidence

  Explain the physics evidence first: identify the medical context, state the relevant quantity or process, then link it directly to Discuss image and illumination transmission..

  AQA A-level medical physics answers score better when they connect the clinical situation to a named physical principle, rather than giving a generic medical description.

• Understanding Endoscopy Advantages

  When explaining the advantages of endoscopy for diagnosis, focus on its minimally invasive nature, ability to provide real-time imaging, and reduced recovery time compared to traditional surgery.

  This helps to clearly articulate the benefits of endoscopy, making it easier to compare with other diagnostic methods and understand its significance in medical practice.

• Apply Magnetic resonance scanner evidence

  Explain the physics evidence first: identify the medical context, state the relevant quantity or process, then link it directly to Describe the role of strong magnetic fields in MRI..

  AQA A-level medical physics answers score better when they connect the clinical situation to a named physical principle, rather than giving a generic medical description.

• Understanding Resonance in MRI

  To explain resonance in MRI, remember that resonance occurs when the frequency of the radio-frequency pulse matches the natural frequency of the hydrogen nuclei in the body. This alignment allows for maximum energy absorption, enhancing image quality.

  This helps because understanding the resonance condition is crucial for grasping how MRI technology works, leading to better explanations in exams.