Non-Ionising Functional and Tissue Imaging (UG)

Module aims

 This module will explain the latest uses and advanced features of medical imaging (CT, X-ray, MR and US) in modern hospital practice. It will also explain the principles of operation of the modalities of CT, X-ray, MR and US and explain how the modalities of CT, X-ray, MR and US can be used safely. It will explain some reasearch imaging tools such as Optical Coherence tomography and the use of different techniques for enhancing contrast.

Learning outcomes

 To know the features incorporated in current medical imaging systems; To know the principles of operation and associated equipment used in advanced imaging features; To know how to optimise the contrast of different imaging modalities; To be aware of the safety guidelines and regulations for ionising and non-ionising radiation; To know how ultrasound can be used for therapy; To know how to check the quality of scanners using routine Q.A. procedures; Be able to calculate Image parameters such as pixel size, beam width etc; Be able to discuss the relative merits of different imaging modalities; Be able to evaluate patient exposures, e.g. radiation dose, SAR etc; Be able to manipulate images in k-space; Be able to assess ultrasound image quality using phantoms.

Module syllabus

 X-ray imaging: image intensifiers, special techniques, DSA, interventional radiology; Digital radiography: digital fluoroscopy, storage media, direct digital radiography, PACS; Advanced image quality: MTF, evaluation of contrast/details thresholds, square wave and edge response functions, ROC analysis, figure of merit; Performance assessment: Quality assurance, test objects, phantoms; Radiation protection: risks and hazards, patient dose, occupational dose, shielding, room design, the critical examination, dose reduction measures, measurement of patient dose, dose surveys; Radiation protection legislation: Guidance, codes of practice, basic safety standards, EU directives; CT Technology: Image Reconstruction from Projections: Algebraic interpretation, Central slice theorem, convolution backprojection, reconstruction filters, effect of filters on image quality, image reconstruction artefacts, spatial sampling and aliasing. Iterative reconstruction, ART and SIRT algorithms, ML reconstruction and EM algorithms. Spiral CT: pitch factor, interpolation, reconstruction, multiple slice systems. Quantitative and functional CT: dynamic CT, bone densitometry, CT angiography, CT fluoroscopy. CT Image Quality: noise, uniformity, slice width, spatial resolution, MTF, figure of merit, test objects, artefacts. CT dosimetry: dose profile, CTDI, practical measurement, patient dosimetry, scattered radiation, radiation protection issues; Ultrasonic Imaging Transducer arrays: Linear, linear phased, annular. Electro-acoustic modelling. U/S Field Theory: Beam Formation, lateral and axial resolution, beam steering, focussing and apodization. Therapeutic Techniques: Bioeffects, thermal interactions/cavitation, transducer array design, beam focussing, clinical studies, ablation, 3D Ultrasound: Position sensing, image data acquisition, interpolation techniques, editing procedures, volume and surface rendering techniques, display modes, ultrasound tomography, QA protocols, Acoustic output measurements, preventative maintenance protocols, first line maintenance. Contrast Agents and Harmonic Imaging: Nature of contrast agents, areas of clinical application, fundamental and harmonic imaging, stimulated acoustic emissions, drug delivery; Dosimetry and Safety: Thermal, non-linear and cavitation effects. Cellular effects. Cooling mechanisms in vivo. Ultrasound field measurements, thermal and mechanical indices, operating parameters, International safety regulations; Magnetic Resonance Imaging: NMR phenomenon. Reference frames, resonance and Bloch equations. MR Hardware: Magnet design and constraints, superconductivity, gradient coil design, gradient performance, eddy currents and shielding. Components of Receiver chain: coil design, coil loading, quadrature and array coils, SNR vs field strength. Advanced pulse sequences: CPMG, Stimulated echoes. Fast Imaging Sequences: k-space, segmented sequences, FLASH, turbo-FLASH, Fast spin-echo, Echo-planar, sequential scanning. Clinical Scanning Techniques: Contrast agents, paramagnetic ions, positive and negative contrast agents, fat suppression, chemical shift, chemical and motion artefacts, gating, STIR, in and out-phase techniques, chemical selection, spatial saturation. MR Angiography: Physics of flow effects, in-flow, phase effects, gradient moment rephasing, time-of-flight MRA, phase-contrast MRA, 2D and 3D techniques, TONE, MIP, quantitative velocity measurement, Fourier encoding; Advanced contrast mechanisms: BOLD effect, diffusion, perfusion, magnetisation transfer. MR Spectroscopy: chemical shift, common nuclei for investigation, spectral features, line widths, technical requirements, localisation methods, CSI. MR Image Quality: SNR and resolution, assessing image quality, test objects, parameters, test materials; MR Safety II: Bioeffects & safety, biological effects of static, time-varying fields, magneto-hydrodynamic effect, neuro-muscular stimulation, heating, SAR, exposure limits and units. Pacemakers, implants, standards, guidance and organisational issues, siting and environmental issues; Biomedical Optics: Optical Coherence Tomography, micro-confocal Endoscopy.

Assessments

 Written exam 100%