Advanced Biomedical Imaging

Dr. Azza HelalDr. Azza HelalA. Prof.A. Prof. of Medical Physics of Medical Physics

Faculty of MedicineFaculty of MedicineAlexandria UniversityAlexandria University

Lecture 2Lecture 2Overview & comparison of different Overview & comparison of different

imaging modalities imaging modalities

Comparison of different imaging Comparison of different imaging modalitiesmodalities

1. Projection views

2.2. Ionizing radiationIonizing radiation

3. Speed

4. Contrast resolution

1.1. Projection viewsProjection views

Limited visualization

Plain x ray & Isotope scan

Flexible imaging planes

Cross-section views CT & MRICT & MRI

Flexible imaging planes with MRI.

MRI angiography

2.2. Ionizing radiationIonizing radiation

Plain x - ray, CT & isotope scan

3. Speed 3. Speed

US Fast Plain x ray CT MRIIsotope scan Slow

4. Contrast4. Contrast

Plain X RayPlain X Ray

CTCTPhysical and electron densityPhysical and electron density

USUS Transmitting & receiving high Transmitting & receiving high frequency sound wavefrequency sound wave

Isotope scanIsotope scan Uptake of radioactive tracerUptake of radioactive tracer

MRIMRI

Transmitting & receiving radio-Transmitting & receiving radio-waves inside a high magnetic fieldwaves inside a high magnetic field

(Water concentration & Magnetic (Water concentration & Magnetic properties)properties)

Contrast resolutionContrast resolution

Plain x ray & CT reflect bone contrast

MRI reflects soft tissue contrast

Assignments Assignments

One student will be selected for assignmentOne student will be selected for assignment

Suggested ReadingsSuggested Readings

David Sutton’s RadiologyDavid Sutton’s Radiology

Physics for medical imaging by RF Fare & PJ Allisy-Physics for medical imaging by RF Fare & PJ Allisy-Roberts.Roberts.

QuestionsQuestions

1.1. Mention the advantages of MRI over CT?Mention the advantages of MRI over CT?

2.2. Enumerate the imaging modalities that use Enumerate the imaging modalities that use

ionising radiation? ionising radiation?