Index

A

Aberrant crypt foci (ACF), 62, 64–66

ABF, see Analog beamforming (ABF)

ACF, see Aberrant crypt foci (ACF)

Acquisition electronics, 372–376

ACS, see Autocalibration signal (ACS)

ACT, see Average CT (ACT)

Active shape models (ASM), 671, 675

AD, see Alzheimer's disease (AD)

ADC, see Analog-to-digital converters (ADCs)

Algebraic reconstruction technique (ART), 132

Alzheimer's disease (AD), 583–584

Analog beamforming (ABF), 223–224

Analog-to-digital converters (ADCs)

CAD tools, 237

design automation, 237–241

output signals, 278

PET and SPECT designs, 375

PMOS and NMOS, 237–238, 240

power efficiency vs. dynamic range, 227

range and bandwidth, 226

SSV technique, 237

TIQ-based, 235–237

TIQ comparator models, accuracy comparison, 239

transistor yields, 241

Application-specific integrated circuits (ASICs), 122, 263, 313

ART, see Algebraic reconstruction technique (ART)

ASICs, see Application-specific integrated circuits (ASICs)

ASM, see Active shape models (ASM)

Attenuation map, creation, 343–348

Autocalibration signal (ACS), 499, 506

Avalanche photodiode (APD)

bias voltage, 385–386

breakdown voltage, 383

representation, 382

electrical signals, 386

Geiger mode, 386

PSAPDs, 384–385

quenching, 386

radiation detectors, 383

spatial resolution, 384

system gain, 383

Average CT (ACT), 174, 185, 186

B

Bayesian network (BN) modeling

directed Markov property and faithfulness assumption, 604

d-separation concept, 603–604

joint probability distribution, 603, 604

network structure, 604–605

neural interactions, 602–603

PC_fdr algorithm, see PC_fdr algorithm

PD, 610–612

BDL, see Biliary duct ligation (BDL)

Beamforming

ABF vs. DBF, 223–224

post processor adds, 223

PPL, 224

receive beamformer, 223

transmit beamformer, 223

ultrasound images, finer resolution, 224

Beam-hardening, 344

Biliary duct ligation (BDL), 584–585

Block detector, 275–277

Block-matching (BM) algorithm, 646

Blood flow, 465–467

Blood oxygen level dependent (BOLD)

amplitude, 594, 595

description, 594

DTI, 595

functional connectivity, 596

GLM, 596

ICA, 599

seed-based ROI method, 597

T₂-weighted contrasts, 570

BM algorithm, see Block-matching (BM) algorithm

B-mode imaging system hardware

A/D converter and memory (FIFO), 222–223

amplifier, 222

block diagram, 222

control host, 221

TGC, 222

T/R switch, 222

BN modeling, see Bayesian network (BN) modeling

BOLD, see Blood oxygen level dependent (BOLD)

Bone and soft-tissue maps, 344

Brain connectivity

diffusion MRI, see Diffusion magnetic resonance imaging (dMRI)

functional MRI

assessment, network modeling methods, 601

behavioral paradigms, 595

BN modeling, see Bayesian network (BN) modeling

BOLD, see Blood oxygen level dependent (BOLD)

clustering methods, 599

conditional-dependence measures, 598–599

connectivity network, ROIs, 612–613

CT method, 597–598

graphical models, 601

group modeling, 601–602

incrementally updatable and hierarchical group analysis, 613

linear decomposition methods, 599

multivariate statistical methods, 600

perturbation analysis, 614

seed-based ROI method, 597

sparse methods, 600–601

temporal and spatial

resolution, 594

Breathing instruction-based methods, PET/CT

DIBH PET/CT, 409–410

normal end-expiration breath-hold, 407–408

shallow breathing, 407

C

CA algorithms, see Coordinate accent (CA) algorithms

CACT, see Cine average CT (CACT)

CAD, see Computer aided design (CAD)

Cadmium telluride (CdTe), detectors, 388–390

Cadmium zinc telluride (CdZnTe), detectors, 388–390

Calcium scoring, 348, 365

Calibration-Less Multicoil (CaLM) MRI

conditions, CS recovery, 514

data acquisition model, 513–514

frequency domain methods, 513

Gaussian sampling, 517

group-sparse reconstruction, 514–516

reconstruction accuracy

brain data and Shepp–Logan phantom, 517–518

Gaussian sampling, 517, 523

GRAPPA, l1SPIRiT and CS SENSE, 519, 521

NMSE, see Normalized mean squared error (NMSE)

objectives, 518

radial sampling, 517, 522

CaLM MRI, see Calibration-Less Multicoil (CaLM) MRI

Capacitive micromachined ultrasonic transducers (CMUTs) imaging systems

applications

large/high-density 2D array, 266–268

small 2D array, 263–265

in vivo, 263

benefits

grating lobes concept, 259–260

IC integration, 260

and PZT transducers, 258–259

smaller pitch, 259–260

wider bandwidth, 258–259

cell, cross-sectional schematic, 255

challenges

dielectric charging, 268–269

efficiency, 269

reliability, 269

transducer elements, cross talk, 269

CMUT–CMOS integration techniques

ASICs, 263

CMUT-in-CMOS, 261

CMUT-on-CMOS, 262–263

flip-chip integration, 261–262

design and fabrication

and application, 254

cavities formation, 257

encapsulation layer, 257–258

horizontal dimension, 256

integrated circuit (IC) production, 255

membrane diameter, 255, 256

silicon nitride and silicon oxide, 257

square-and hexagon-shaped membranes, 256

MEMS-based transducer, 254

scanning electron microscope image, 254

ultrasonic transducers composition, 254

Cardiac imaging, 416–417

Cascaded system theory (CST), 94

CCD, see Charge-coupled devices (CCD)

CEST imaging, see Chemical exchange saturation transfer (CEST) imaging

CFD, see Constant fraction discriminator (CFD)

Charge-coupled devices (CCD), 110, 113, 140

Charge-sensitive preamplifier (CSA), 372–374

CHARMED, see Composite hindered and restricted model of diffusion (CHARMED)

Chemical exchange saturation transfer (CEST) imaging, 571–572

CIE color functions, see Commission Internationale d'Eclairage (CIE) color functions

Cine average CT (CACT), 411–413

Closed-form solutions, MIR

affine transformations, 636

Bayesian energy, 635–636

least squares (LS) error, 634–635

nonlinear transform, 634

spectral algorithms, 636

Clustering methods, brain connectivity, 599

CMOS, see Complementary metal oxide semiconductor (CMOS)

CMUTs imaging systems, see Capacitive micromachined ultrasonic transducers (CMUTs) imaging systems

CNR, see Contrast-to-noise ratio (CNR)

Commercial helical 4DCT systems, 182–183

Commission Internationale d'Eclairage (CIE) color functions, 73, 74

Compartmental model

blood flow, 465–467

glucose metabolism, 467–468

receptor-ligand binding

DVR, 470

equilibrium dissociation constant, 468

radioligand concentration, plasma, 469

single-tissue compartment, 470

time–activity curves, 470–471

Complementary metal oxide semiconductor (CMOS), 118, 119, 125, 130

Composite hindered and restricted model of diffusion (CHARMED), 542–543

Compressed sensing (CS), MRI acceleration

description, 485

estimation, sparse vector, 486

hardware and software based approaches, 485–486

multichannel scans

calibration-free parallel MRI reconstruction, see Calibration-Less Multicoil (CaLM) MRI

data acquisition process, 499

k-space samples, 499

SENSE-based reconstruction, 500–513

SMASH, GRAPPA and ACS, 499

NP hard problem, 487–488

single-channel MRI scans

data acquisition model, 488

k-space, 488

low-rank matrix, see Low-rank matrix, MRI reconstruction

sparse modeling, 488–493

Compton interaction, 282–283

Computed tomography (CT)

iterative methods, 210

protocols

CACT, 411–413

IACT, 413–414

low-pitch CT, 411

scan modes, 410

slow CT, 410–411

Computer aided design (CAD), 237

Cone-beam

artifacts, 212

reconstruction

description, 204

3-D-radon data, 207, 208

fan-to-parallel-beam rebinning method, 206

FBP methods, 204, 205

FDK algorithm, 205

hybrid filtering approach, 205–206

image artifacts, 207

phantom, 207

Wedge algorithm, 206

Constant fraction discriminator (CFD), 279

Contrast-to-noise ratio (CNR)

dual-energy imaging, 153

lesion detection, 155

performance, 303

Coordinate accent (CA) algorithms, 441–442

Corticospinal fluid (CSF), 531

Crossed electrodes, see Row-column (RC)

CSA, see Charge-sensitive preamplifier (CSA)

CSF, see Corticospinal fluid (CSF)

CSI, see Cubic spline interpolation (CSI)

CST, see Cascaded system theory (CST)

CT, see Computed tomography (CT)

CT-based co-registration, 361–362

CT protocols, see Computed tomography (CT)

CT-SPECT/CT-PET

attenuation

accurate correction, 338–339

beam-hardening, 344

blurred image, 344

bone and soft-tissue maps, 344

contrast, 345–346

CT vs. transmission scans, 338–339

Hounsefield units, 343

map, creation, 343–348

max-intensity CT, 348

metal objects, 345

patient movement, 345

respiratory artifact, 345–347

truncation, 344–345

CTAC

advantages, 339–341

disadvantages, 341–342

FDG PET/CT whole-body study, 340

field-of-view (FOV), 339

photon flux, 339

radioactive sources, 339

speed, 341

diagnostic information

calcium scoring, 348

high-resolution anatomical map, 348–349

non-oncologic studies, 348

radiotracers, 349

dose modulation, 342–343

image registration

motion compensation, areas, 351

nonlinear registration algorithms, 351

patients movements, 350–351

rigid-body registration, 349

semi-automated methods, 349

software registration, 349–351

warping algorithms, 350

localization advantages

bone scan, 338

cancer, focal sites, 337

cardiac imaging, 338

DEFER trial, 338

hybrid imaging, 337–338

nuclear medicine, 337

MRI

absolute quantification, 352

cost-effectiveness, 353

metal implants, 353

patient-specific attenuation, 353

photomultiplier tubes, 352

radiofrequency radiation, 351–352

solid-state amplification, 352

multislice scanners, 336

types, 342–343

“unclear medicine”, 335

Cubic spline interpolation (CSI), 40–41

CZT, see Cadmium zinc telluride (CdZnTe), detectors

D

DAG, see Directed acyclic graph (DAG)

Data acquisition, micro-CT systems

calculation, 130

continuous rotation, 128

detector integration period, 129

online correction, raw data, 130–131

parameters, 129–130

projection images, 129

step-and-shoot approach, 128

Data interpolation, MIR, 621–622

Data sufficiency condition (DSC), 176–178

DBF, see Digital beamforming (DBF)

DCT, see Discrete cosine transformation (DCT)

4DCT, see Four-dimensional computed tomography (4DCT)

Deconvolution PET/CT, 421–422

Deep-inspiration breath-hold (DIBH) PET/CT, 409–410

Demons algorithm, MIR

Gaussian smoothing, 643

LDDD, 645–646

modification, 645

orientation and magnitude, forces, 643

PASHA algorithm, 644

Depth-of-interaction (DoI)

capability, 315–316

detector design concepts, 315

dual-layer crystals, offset positions, 316–317

monolithic crystals, statistical positioning, 316

multiple crystal-photodetector layers, 314

Phoswich design, 315

single-crystal layer/dual-ended photodetectors, 314–315

TRI and RECT crystal, 317

Detector response function (DRF)

counting direct conversion detectors, 103–105

definition, 100–101

indirect and direct conversion detector, 101–102

integrating indirect conversion detectors, 102–103

spectral behavior, 102

DFT, see Discrete Fourier transformation (DFT)

DIBH PET/CT, see Deep-inspiration breath-hold (DIBH) PET/CT

Diffusion magnetic resonance imaging (dMRI)

anisotropy, tissue, 531

brain connectivity mapping

front propagation tractography, 553–556

probabilistic tractography, 550–553

streamline tractography, 548–550

Brownian motion, 530

CSF, gray matter and white matter, 531

description, 530, 556

diffusion tensor, see Diffusion tensor

DWI, 533–535

eddy currents, 535–536

HARDI, see Higher angular resolution diffusion imaging (HARDI)

model correction, 547–548

molecular displacement, 530

MRI, 532–533

noise reduction, 547

Rician noise, 536–537

spin property, magnetic moment, 531–532

subject motion, 536

Diffusion ODF, see Diffusion orientation distribution function (ODF)

Diffusion orientation distribution function (ODF)

DOT, 544

q-ball imaging, 543

tractosema, 548

visualization, HARDI, 544–546

Diffusion orientation transform (DOT), 544

Diffusion tensor

Brownian motion, PDF, 537

eigendecomposition, 538–539

ellipsoid, 539

fitting procedure, 538

vs. HARDI, 546–547

mean diffusivity (MD) and fractional anisotropy (FA), 539–541

q-space imaging, 537

quality, 538

visualization strategy, 540, 541

zero-mean Gaussian, 538

Diffusion tensor imaging (DTI), 595, 613

Diffusion-weighted imaging (DWI)

brain's white matter, 534, 535

eddy currents, 535–536

gradient direction, 535

HARDI, see Higher angular resolution diffusion imaging (HARDI)

magnetic pulse, spin direction, 533

Stejskal–Tanner, 533

subject motion, 536

T₂ relaxation times, 534

Digital beamforming (DBF), 223–224

Digital signal interfacing, 225

Digital SiPM

ADC and TDC functions, 324

CMOS

fabrication process, 325–326

process, 323

dark count rate (DCR), 323

in-pixel electronics, 326–327

quenching, 323

Direct conversion detector

cathode CZT, 92

counting, 103–105

flat-panel X-ray

ambient conditions, 120–121

ASIC, 122

cadmium telluride (CdTe), 121

crystallization and stabilize material, 121

design, contact plates, 121

electric charges, 119, 120

photoconductor materials, 119–120

TFTs, 122

parameters, 94

primary energy deposition, 96

pulse generation, 96–97

signal conversion steps, 92, 93

Direct conversion detectors, 297–298

Directed acyclic graph (DAG), 603–604, 606, 607

Discrete cosine transformation (DCT), 625

Discrete Fourier transformation (DFT), 625

Discrete optimization, see Markov Random Field (MRF) energy minimization

Distribution volume ratio (DVR), 470

Dixon's composite spin-lock pulse and phase cycling, 577–578

dMRI, see Diffusion magnetic resonance imaging (dMRI)

DoI, see Depth-of-interaction (DoI)

DOT, see Diffusion orientation transform (DOT)

DRF, see Detector response function (DRF)

DSC, see Data sufficiency condition (DSC)

DTI, see Diffusion tensor imaging (DTI)

Dual-energy CT imaging

acquisition, see Image acquisition

description, 147

noise suppression, 163–168

patient motion, 149

post-contrast single-energy abdomen CT exam, 148

reconstruction, see Image reconstruction, dual-energy x-ray CT imaging

“rotate–rotate” technique, 149

visualization and clinical applications

beam-hardening reduction, 168–169

hepatic cyst, 166

histograms/scatterplots, 167

metal artifact reduction, 169

monochromatic energy, 165–166

Dual-layer crystals, offset positions, 316–317

Dual window (DW) processing method

calculation, 56, 57

depth resolved spectra, 57, 58

Gaussian distribution, 57

local oscillations, 58

STFT, 56, 57

time-frequency distribution (TFD), 56–57

windowed data, 56

DVR, see Distribution volume ratio (DVR)

DWI, see Diffusion-weighted imaging (DWI)

Dynamic PET data model, 452–453

E

EAs, see Evolutionary algorithms (EAs)

Eddy currents, 535–536

Electronics, PET and SPECT imaging

ADC, 375

bias capacitor, voltage, 373

event location, 375

gamma ray deposition, 376

Gaussian shapers, 374–375

high count rates, measurement, 375

multiple modular detector blocks, 376

output voltage, 374

photocurrent, 372

preamplifier (pre-amp), 372

VSA, 372–374

EM algorithm, see Expectation maximization (EM) algorithm

EMPIRE, see Evaluation of Methods for Pulmonary Image Registration (EMPIRE)

Energy functions, MIS

boundary and region, 555, 664

challenges, 679

description, 664

GACs, 666

GAs, 674–675

graph cuts, 674

image representation, 670–671

noise, 666

parameters, 668

piecewise-constant functions, 667

SDF, 669, 670

shape-based terms, 667

weight optimization, 667–668

ENF, see Excess noise factor (ENF)

Euler–Lagrange equation, 673, 680–681

Evaluation of Methods for Pulmonary Image Registration (EMPIRE), 649–650

Evolutionary algorithms (EAs), 639–640

Excess noise factor (ENF), 289

Expectation maximization (EM) algorithm

closed-form solution, 446

concave function, 443–444

E-step, 443

generalized EM (GEM), 445

pair-wise penalty, 445

Poisson log-likelihood function, 444

EyeCam

camera, 4

durability, 3

electrical impulses, 2, 3

person's eyesight, 2

size, power and heat, 3

F

FACT approach, see Fiber assignment by continuous tracking (FACT) approach

Fan-beam projections

analytical methods, 197

backprojection process, 200

divergent rays, 200

kernel h_R shift-invariant, 198

and parallel-beam projections, 197, 198

parameters, 197, 198

pin-hole and divergent collimators, 197

ramp filter kernel, 199

Fan-to-parallel-beam rebinning method, 206

Fast-kVp switching (FKS), see Dual-energy CT imaging

FDA, see Food and Drug Administration (FDA)

FDK algorithm, see Feldkamp algorithm (FDK) algorithm

FD-OCT, see Fourier domain OCT (FD-OCT)

Feldkamp algorithm (FDK) algorithm, 205

FFD, see Free-form deformation (FFD)

¹⁸F–fluorodeoxyglucose (FDG) imaging, 364

Fiber assignment by continuous tracking (FACT) approach, 549, 550

Fiber-optic coupling

limitations, 380

McPET I, 379–380

McPET II, 380

timing resolution, 380

Field-cycled MR, 378–379

Field-programmable gate array (FPGA)

chip, 229

FD-OCT image reconstruction, 25

Filter kernel, 196–197

Flat-panel X-ray detectors

Argus PET/CT, 124

classification, 114

CMOS, 125

direct conversion, 119–122

edge response function (ERF), 134, 135

features, 124

Hamamatsu C7940DK-02, 124

indirect conversion, 115–119

magnification factor, 135–136

MTF and, 135

protocol, measurement, 133–134

scintillator layer, 125

slanted-edge method, 134

small-animal imaging, 114

temporal instability, 133

fLCI, see Fourier domain low coherence interferometry (fLCI)

Food and Drug Administration (FDA), 578

Four-dimensional computed tomography (4DCT)

ACT and MIP CT, 185, 186

commercial helical 4DCT systems, 182–183

data acquisition modes, 178, 179

description, 185–186

DSC, 176–178

image artifacts, 184–185

image location, slice thickness and scan time, 178, 180

LightSpeed MSCT scanner, 174, 175

respiratory monitoring devices, 183–184

respiratory motion, 173–174

scan modes, 176

Siemens Somatom 4-slice CT, 174–175

slow CT scan, 174, 175

work flow and phase selection accuracy, 180–182

Fourier domain low coherence interferometry (fLCI)

ACF and, 62, 64–66

animal experimental protocols, 63

average spectrum, 64, 65

depth resolved DW spectra, 60–62

ex vivo hamster cheek pouch carcinogenesis model., 62

light scattering, 58, 59

LSS and, 59, 62

measurement, 58

neoplastic development, 66

nuclear morphology measurements, 64, 66

pfdOCT system, 63, 64

phantom, 60

polystyrene microsphere, 60

scattering properties, 59

statistical analysis, 64

Fourier domain OCT (FD-OCT)

A-scan depth-resolved imaging, 30–31

data processing

numerical dispersion compensation, 41–42

numerical interpolation method, see Numerical interpolation method

volume rendering, 42–43

description, 28–29

imaging resolution and depth, 31, 32

spectrometer-based spectral domain, 29

swept-laser-based swept-source, 29

system design

configuration, 36–38

data processing flow, 38

Fourier rebinning

approximation, FORE, 435–436

description, 432–433

FORE-J, 434–435

FOREX algorithm, 434

oblique projections, 433–434

Fourier slice theorem, 191–193

FPGA, see Field-programmable gate array (FPGA)

FPGA chip, see Field-programmable gate array (FPGA)

Free-form deformation (FFD), 624–625, 631, 642

Front propagation tractography

description, 553

fast marching tractography, 553–554

flow simulation, 554–555

minimal path algorithms, 555–556

Full width half maximum (FWHM), 302

Functional imaging technique, 360

FWHM, see Full width half maximum (FWHM)

G

GACs, see Geodesic active contours (GACs)

GAPD cells, see Geiger-mode avalanche photodiode (GAPD) cells

GAs, see Genetic algorithms (GAs)

Gated four-dimensional (4D) PET/CT

breathing motions and ¹⁸F-FDG uptake, 414

description, 423

distances, lesion centroids, 415, 416

reconstruction-based methods

advantage, 420

data acquisition, 418–419

deformation matrices, 419

motion compensation, 418

OPL-EM algorithm, 419

OS-EM technique, 419–420

registration-based methods

cardiac imaging, 416–417

frames, 416

lung imaging, 417–418

RPM marker location and electrical triggers, 414, 415

Geiger-mode avalanche photodiode (GAPD) cells, 292–293

Generalized autocalibrating partially parallel acquisitions (GRAPPA)

description, 507

image reconstruction

brain, 510

rat ex vivo 1, 511

rat in vivo 1, 512

UBC MRI phantom 1, 511

iSENSE CS vs. iSENSE NN, 508–509

Generalized least squares (GLS), 474, 477

Generalized weighted least squares (GWLS), 474, 477

General linear model (GLM), 596

General-purpose computing on graphics processing units (GPGPU), 25, 26

Genetic algorithms (GAs), 674–675

Geodesic active contours (GACs), 666, 678

GLM, see General linear model (GLM)

GLS, see Generalized least squares (GLS)

Glucose metabolism, 467–468

GPGPU, see General-purpose computing on graphics processing units (GPGPU)

Gradient-based algorithms

active set approach, 440–441

Hessian matrix, 440

Newton–Raphson method, 439

PCG algorithm, 440

Gradient-based optimization

gradient descent method, 637

Kiefer–Wolfowitz method, 638

QN and NCG methods, 638

GRAPPA, see Generalized autocalibrating partially parallel acquisitions (GRAPPA)

Group modeling, brain connectivity, 601–602

GWLS, see Generalized weighted least squares (GWLS)

H

Halfscan artifacts, 213

Half-value thickness (HVT), 338

HAMMER, see Hierarchical Attribute Matching Mechanism for Elastic Registration (HAMMER)

Health care

digital and medical imaging

companies and industry, 7

evolution, 5

fusion, multiple imaging modalities, 6

migration to digital files, 5

moving, diagnostic to therapeutic, 5–6

real-time processing, 5

ultrasound, 6

wireless connectivity, 6

life-changing application, medical technology, 4

medical devices, 4

Hierarchical Attribute Matching Mechanism for Elastic Registration (HAMMER), 634, 647

Higher angular resolution diffusion imaging (HARDI)

CHARMED and FORECAST methods, 542–543

diffusion ODF, 544–546

vs. diffusion tensor, 546–547

DOT, 544

fibrous tissues, 541–542

limitations, 543

neural pathways, 542

PAS approach, 544

q-ball imaging, 543–544

Stejskal–Tanner equation, 542

High photon detection sensitivity

dual-panel CZT-based PET system, 305–306

geometric efficiency, 304

intrinsic coincidence detection efficiency, 304

parallax error, 304–305

PET instrumentation, 303–304

rectangular PET detectors and, 306

tapered crystals, 306–307

High-voltage excitation pulses, 225

Hounsfield units (HU), 343, 364

HU, see Hounsfield units (HU)

HVT, see Half-value thickness (HVT)

I

IACT, see Interpolated average CT (IACT)

ICA, see Independent component analysis (ICA)

ICE, see Intracardiac echocardiography (ICE)

ICS, see Intercrystal scatter (ICS)

ICs, see Integrated circuits (ICs)

Image acquisition

detector, 151–153

dose

CTDI_vol, 157, 158

LCD, 155, 156

phantom, 155, 156

region of interest (ROI), 156–157

flux

CNR, 153

FKS dual-energy, 153, 154

modulating, tube current, 154

noise reduction processing, 152

simulated low-contrast lesion, 155

x-ray exposure, 153

X-ray tube/generator, 150–152

Image co-registration, 362

Image reconstruction (IR)

artifacts, 211–213

central slice theorem, 191–193

cone-beam reconstruction, see Cone-beam

3D PET

data model, 436–437

dynamic PET data model, 452–453

Fourier rebinning, 432–436

Fourier transform, parallel projections, 430–432

linear kinetic models, 454–455

ML and PL methods, 437–439

nonlinear kinetic models, 456

optimization algorithms, see Optimization algorithms

PET scanners, 429–430

2-D Radon transform, 190

dual-energy x-ray CT imaging

effective atomic number, 162–164

energy-dependent attenuation measurements, 159

material density map, 160–161

monochromatic energy, 161–162

projection-space material decomposition, 158–159

fan-beam projections, see Fan-beam projections

FBP, 193–195

filter kernel, 196–197

Hilbert transform, 211

iterative reconstruction methods, see Iterative image reconstruction

parameters, 190

redundancy

backprojection, 203, 204

conjugate ray, 201

electrocardiogram-gated cardiac image, 203

fan-beam projections, 203

halfscan algorithm, 202

primary ray, 201

scan / partial scan, 203

sinograms, 201, 191

weighting function, 202–203

spatial distribution, 189

trans-axial truncation, 211

Improved spatial resolution

anger-logic PET block detector, 311

complex and expensive assembly, 308–309

compton scatter and multiple interactions, 310

high-density data acquisition systems, 312–313

high-resolution PET detector developments, 312

MTF, 307

PET image quality, 307

PSF, 307

reduced scintillation light output, 309–310

Rose criterion, 308

spatial decoding, block detectors, 310–312

Independent component analysis (ICA), 597, 599

Indirect conversion detectors

CT scintillation detector, 91

electronic read-out, 96

flat-panel X-ray

light transport, nonstructured scintillator screen, 117

optical photons, 115

photon energy, 115–116

scintillation materials, 115, 116

secondary quanta detection, 118–119

semiconductor detector, 117

integrating, 102–103

light transport and detection, 96

parameters, 94

primary energy deposition, 94, 96

signal conversion steps, 92, 93

¹¹¹In-labeled imaging, 365

Integrated circuits (ICs), 1, 11, 13, 21

Intercrystal scatter (ICS), 282–283

Interpolated average CT (IACT), 413–414

Intracardiac echocardiography (ICE), 263–264

Intravascular ultrasound (IVUS), 263–264

IR, see Image reconstruction (IR)

iSENSE method

GRAPPA and JSENSE, 510–512

iSENSE CS vs. iSENSE NN, 508–509

reconstruction

accuracy, 507–508

times, 512–513

SparSENSE and NNSENSE, 507

Iterative image reconstruction

CT, 210

SPECT and PET, 208–210

IVUS, see Intravascular ultrasound (IVUS)

J

Joint image reconstruction and sensitivity estimation in SENSE (JSENSE)

Chebyshev polynomials, 502

CS and nuclear norm minimization, 504–506

iSENSE CS vs. iSENSE NN, 508–509

reconstructed and difference images

brain, 510

rat ex vivo 1, 511

rat in vivo 1, 512

UBC MRI phantom 1, 511

JSENSE, see Joint image reconstruction and sensitivity estimation in SENSE (JSENSE)

L

Large/high-density 2D array

row-column (RC), 267–268

sparse array, 266, 267

synthetic array, 266–267

LCD, see Low-contrast detectability (LCD)

LDDD, see Log Domain Diffeomorphic Demons (LDDD)

Light scattering spectroscopy (LSS), 59, 60, 62

Linear kinetic models, 454–455

Linear least squares (LLS)

description, 474

single-tissue compartment models

dynamic H₂15O PET, 478

LWLS and GWLS, 477

measurements, 476

time–activity curves, 476, 478

two-tissue compartment models

irreversible binding, 479–480

reversible binding, 480–481

Linear spline interpolation (LSI), 39–40

LLS, see Linear least squares (LLS)

LNA, see Low-noise amplifier (LNA)

Log Domain Diffeomorphic Demons (LDDD), 645–646

Low-contrast detectability (LCD), 155–157

Low-field MR, 377–378

Low-noise amplifier (LNA), 222

Low-pitch CT, 411

Low-rank matrix, MRI reconstruction

brainWeb and NIH, CSMRI

comparison, 498

description, 499

Haar wavelet, 496–497

NMSE, 497

proposed approach, 497, 498

SPGL1, 496

k-space measurements, 495

l_p-norm minimization, 496

rank minimization, 495

Schatten-p-norm, 496

spatial redundancy, 493

SVD, 493, 498

Low-voltage high-frequency transducer, 225

LSI, see Linear spline interpolation (LSI)

LSS, see Light scattering spectroscopy (LSS)

Lumbar spinal fusion, 580

M

Magnetic compatibility

collimator material, 392–393

eddy currents generation, 391

magnetic field gradients, 392

PET and SPECT shielding materials, 390

radiation detection, 391–392

spatial resolution measurements, 392

susceptibility, 391

Magnetic resonance imaging (MRI)

acceleration, CS, see Compressed sensing (CS), MRI acceleration

configurations

field-cycled MR, 378–379

low-field MR, 377–378

imaging, 376–377

precession, 532

relaxation, 532–533

resonance, 532

T_1rho, see T_1rho MRI

MAP inference, see Maximum a posterior (MAP) inference

Markov Random Field (MRF) energy minimization

conditional probability, 640

FFD transformation model, 642

fusion-move approach, 642

Gaussian noise model, 641

MAP inference, algorithms, 641

Mass attenuation coefficient, 343

Material density map, 160–161

Maximum a posterior (MAP) inference, 640–642

Maximum intensity projection (MIP) CT, 185, 186

Maximum likelihood (ML)

EM, 440, 444, 454, 455

images, regularization, 437, 438

Kuhn–Tucker conditions, 439

Mean square error (MSE), 648

Medical image registration (MIR)

applications, 620

BM algorithm, 646

closed-form solutions, 634–636

data dissimilarity

feature-based information, 634

hybrid approaches, 634, 635

intensity inhomogeneities, 633–634

model-based information, 632

mono-modality registration, 633

data interpolation, 621–622

Demons algorithm, 643–646

description, 619–620

evaluation

brain image, nonlinear algorithms, 650

EMPIRE, 649–650

gradient-based optimization, 648

landmarking 3D images, 649

misalignments, 648

MSE and PSNR, 648

NIREP, 649

split window validation, 647

TRE and segmentations, 648–649

HAMMER, 647

image representation and imaging terminologies, 621

iterative optimization

discrete, 640–642

EAs, 639–640

functional landscape, 636–637

gradient-based, 637–638

gradient-free, 638–639

line search scheme, 637

search approaches, 639

mathematical formulation, 626

regularization

description, 626–627

inverse consistency, 631

invertibility, 631

local rigidity, 632

smoothness, see Smoothness regularization, MIR

volume-preservation (VP), 631–632

x-ray breast images, 627

spatial (geometric) transformations, see Spatial transformations, MIR

Medical image segmentation (MIS)

Bayesian methods, 676–677

boundary, region and shape, 663

convex relaxation, 674

corpus callosum (CC), 662

deformable models, 664, 665

description, 661–662

energy function, see Energy functions, MIS

Euler–Lagrange equation, 673, 680–681

expert segmentations, 678

GAs, 674–675

gradient-descent process, 673

graph cuts, 674

image representation, 670–671

min-path techniques, 673–674

multiobjective optimization, 675–676

registration, segmentation, 677

segmentation representation, 668–670

snakes, derivations, 681–683

Sobolev-type inner products, 673

synthetic data, 678–679

training data

ASM and PCA, 671

linear statistics, 671–672, 679–680

vessel segmentation, 677–678

Medical imaging

automated monitoring, 9–10

creations inspired, imagination, 21, 22

development cost, 12–13

eyecam, 2–4

health care, 4–7

ICs, 1

innovation drives technology, 10

Moore's law, 11, 12

multiprocessor complexity, 14–16

noninvasive techniques, 21

performance, 13–14

perpetual devices, 18–19

power dissipation, 16–18

process technology, 11, 12

retinal scanner, 11

SoC and SiP, 19–21

telecommunications complements, 7–9

transistor, 10, 12, 21

MeTRiCS, see Molecular imaging true color spectroscopic (MeTRiCS)

MIP CT, see Maximum intensity projection (MIP) CT

MIR, see Medical image registration (MIR)

ML, see Maximum likelihood (ML)

Modulation transfer function (MTF)

definition, 97

flat-panel X-ray detectors, 135

properties, 98–99

simulation and measurement, 97–98

spatial resolution, 307–308

Molecular imaging true color spectroscopic (MeTRiCS)

absorbing species, 80

Beer's law, 68

biomedicine, molecular imaging focuses, 68

calculation, correlation coefficients, 71, 72

CIE color functions, 73, 74

concentration values, 71–72

conventional OCT imaging, 77–78

detector saturation, 82

DW processing, 75

endogenous and exogenous contrast, 77

en face image, 78, 79

fluorescence imaging, 67

glass capillaries, 74–75

images, chick embryos in vivo, 76–78

incoherent fluorescent light, 82

influences absorption spectra, 70

light focus, 68

measurements, 69–71

molar extinction coefficients, 69

oxygen saturation, 71

pfdOCT system, 67

photograph and pfdOCT image, 72, 73

potential impact, 76–77

quantitative spectral information, 73

RGB values, 74

sensitivity, 69

SOCT, 68

sodium fluorescein (NaFS), 79–82

supercontinuum laser light source, 67

tomographic images, mouse dorsal skin flap, 78–80

variations across individual vessels, 79

visible region, spectrum, 72

wavelength, 79, 81

Monochromatic energy image, 161–162

Monolithic crystals, statistical positioning, 316

Moore's law, 11–13, 21

MRF energy minimization, see Markov Random Field (MRF) energy minimization

MSE, see Mean square error (MSE)

⁹⁹mTc-MDP bone imaging, 365

MTF, see Modulation transfer function (MTF)

Multi-anode PMT (MA-PMT), 291–292

Multicoil parallel MRI, see Compressed sensing (CS), MRI acceleration

Multimodality imaging systems

alpha blending, PET/CT images, 363

CT attenuation correction, 363–364

CT-based co-registration, 361–362

image co-registration, 362

image display, 363

magnetic compatibility, 390–393

MR attenuation correction, 394

nuclear medicine images, 360

PET/CT and SPECT/CT, clinical applications

calcium scoring, 365

¹⁸F–fluorodeoxyglucose (FDG) imaging, 364

¹¹¹In-labeled imaging, 365

^{99 m}Tc-MDP bone imaging, 365

myocardial perfusion imaging, 365

PET/MR and SPECT/MR requirements, 367

PET/MR system, 393

problems

beam hardening, 365–366

nuclear medicine, 366

soft-tissue contrast production, 367

time scales, 366

x-ray CT scans, artifacts, 366

radionuclide transmission imaging, 361

RGB color channels, 363

system design, 393–394

“unclear” medicine, 361

whole-body PET scan, 360

Multi-pixel Geiger-mode APD, 386–388

Multiple crystal-photodetector layers, 314

Multislice scanners, 336

Myocardial perfusion imaging, 365

N

National Institute of Health (NIH), 496–498

NCG method, see Nonlinear conjugate gradient (NCG) method

NEC, see Noise equivalent count (NEC)

NECR, see Noise equivalent count rate (NECR)

NIH, see National Institute of Health (NIH)

NIREP, see Nonrigid Image Registration Evaluation Project (NIREP)

NLS, see Nonlinear least squares (NLS)

NMSE, see Normalized mean squared error (NMSE)

NNSENSE, see Norm-regularized SENSE reconstruction (NNSENSE)

Noise equivalent count (NEC), 303

Noise equivalent count rate (NECR), 289

Non-deterministic polynomial (NP) hard problem, 487–488, 495, 496

Nonlinear conjugate gradient (NCG) method, 638

Nonlinear least squares (NLS), 474–475

Nonlinear registration algorithms, 351

Nonrigid Image Registration Evaluation Project (NIREP), 649

Non-separable quadratic surrogate (SQS) function, 447–448

Non-SQS function, see Non-separable quadratic surrogate (SQS) function

Normal end-expiration breath-hold protocol, 407–408

Normalized mean squared error (NMSE)

CaLM MRI reconstruction, 521

CS SENSE reconstruction, 519, 520

GRAPPA and l1SPIRiT

reconstruction, 519

iSENSE CS vs. iSENSE NN, 508–509

proposed and CS reconstruction, 497

reconstruction accuracy, Cartesian undersampling, 492–493

Norm-regularized SENSE reconstruction (NNSENSE)

brain images, iSENSE NN, 509–510

description, 501

GRAPPA, 507

reconstruction accuracy, 508–509

NP hard problem, see Non-deterministic polynomial (NP) hard problem

Numerical interpolation method

CSI, 40–41

linear spline interpolation, 39–40

spectral signal, 39

O

OA, see Osteoarthritis (OA)

OCT, see Optical coherence tomography (OCT)

One-pass list-mode expectation-maximization (OPL-EM) algorithm, 419

OPL-EM algorithm, see One-pass list-mode expectation-maximization (OPL-EM) algorithm

Optical coherence tomography (OCT)

application, 83

chromatic dispersion and compensation, 34–36

chromophores, 83

concept, 25

DW signal processing method, see Dual window (DW) processing method

FD-OCT, see Fourier domain OCT (FD-OCT)

FD-OCT system, schematic, 54

fLCI, see Fourier domain low coherence interferometry (fLCI)

full-range Fourier domain, 34, 35

fundamental imaging modes, 24

GPGPU, 25

high-frequency oscillations, 82

imaging

capabilities, 47

instruments measure structure, 54

tools, 83

and interference, 26–27

interferometry scheme, 53

low coherence interferometry (LCI), 53

and MeTRiCS, see Molecular imaging true color spectroscopic (MeTRiCS)

multidimensional imaging

2D cross-sectional imaging, realtime, 43–45

3D (4D) imaging, real-time, 43, 46, 47

parameters,3D biomedical imaging modalities, 24, 25

phantom, 82

SOCT, 54, 55

STFT, 54, 55

submicronlevel resolutions, 25

TD-OCT, 27–28

tissue absorption, 32–33

tissue scattering, 33–34

Optimization algorithms

CA algorithms, 441–442

gradient-based algorithms, 439–441

Kuhn–Tucker conditions, 439

transfer methods

EM algorithm, 443–446

OSEM, 449–452

QSCA, 446–448

SQS, 448–449

surrogate functions, 442–443

Ordered-subset EM (OSEM) algorithm

augmented cost function, 450–451

convergence rates, 450

convergent OSEM (COSEM), 451–452

EM surrogate function, 451

sub-objective function, 449–450

Ordered subset-expectation-maximization (OS-EM) technique, 419–420

OSEM algorithm, see Ordered-subset EM (OSEM) algorithm

Osteoarthritis (OA), 582–583

P

Parallax error, 304–305

Parallel-beam projections, 193–195

Parallel frequency domain OCT (pfdOCT), 67, 69, 72–74

Parkinson's disease (PD), 583, 584, 610–612

Patient-specific attenuation, 353

PCA, see Principal component analysis (PCA)

PCC-SL, see Phase-cycled composition spin-lock (PCC-SL)

PC_fdr algorithm

conditional variables, 605–606

error control criteria and results, multiple testing, 606–607

gPC⁺_fdr algorithm, 608, 609

group-level model, 609

mixed-effect model, 610

partial correlation coefficient, 608

pseudo-code, 605

sample size approaches, 607–608

PCG, see Preconditioned conjugate gradient (PCG)

PD, see Parkinson's disease (PD)

PDD, see Primary diffusion direction (PDD)

PDM, see Point distribution model (PDM)

Peak-Signal-to-Noise Ratio (PSNR), 648

Penalized-likelihood (PL), 438–439, 445, 447

Penn State ultrasound imaging system

FPGA chip, 229

mode set, 229

transceiver chip, 229–230

transmit signal generator, 230

PET, see Positron emission tomography (PET)

PET and SPECT imaging

electronics, 372–376

photodetectors, 369–372

radiation detectors, see Radiation detectors

scintillation detectors, 367–369

PET/CT, see Thoracic PET/CT

PET detectors

advanced

direct conversion detectors, 297–298

photodetectors, 297

PS-PMT, 291–292

scintillator configurations, alternative photodetector, 293–296

semiconductor photodetectors, 292–293

block detector, 275–277

collinear emission, 274

electronics, 278–279

field-of-view (FOV), 274

high-performance

coincidence events, 302–303

DoI design, see Depth-of-interaction (DoI)

fast and high-Z scintillation materials, 320–321

high photon detection sensitivity, 303–307

improved spatial resolution, see Improved spatial resolution

principles, 302–303

SiPM detectors, see SiPM devices

ToF PET, see Time-of-flight PET (ToF PET)

line-of-flight (LOF), 273–274

noise

detection efficiency, 284

multiple coincidence, 285

prompt coincidences, 285

random counts, 285, 288–290

scatter counts, 284–288

sources, 284

photodetectors, 297

scintillators, see Scintillators

spatial resolution issues

ICS, 282–283

light sharingtechnique, 282

line-of-response (LOR), 281–282

noncollinearity and positron range, 280–281

pixilated detector solutions, 282

radial elongation, 282

radioisotopes, 280–281

technological contribution, 281–284

timing window, 278–279

pfdOCT, see Parallel frequency domain OCT (pfdOCT)

Phase-cycled composition spin-lock (PCC-SL), 578

Phased-array focusing, 259

Phase locked loop (PPL), 224

Phoswich design, 315

Photodetectors, see Photomultiplier tube (PMT)

Photodiodes

avalanche, see Avalanche photodiode (APD)

capacitance, 381

composition, 380

Digirad 2020Tc, 381–382

inherent Q.E., 380–381

leakage current, 381

multi-pixel Geiger-mode avalanche, 386–388

PMTs and, 380

radiation detectors, 381

thermal ionizations, 381

Photomultiplier tube (PMT)

capacitor, 372

collector anode, 370

dynode, 370

electron multiplication stage, 369–370

magnetic field effect, 372

multiplier tube efficiency, 370

photomultiplier tube, 369

primary photons, transition, 372

quantum efficiency (Q.E.), 369

secondary electrons, 372

voltages configuration, 370–371

PHS, see Pulse height spectrum (PHS)

PL, see Penalized-likelihood (PL)

Point distribution model (PDM), 671, 675

Point spread function (PSF), 307

Portable high-frequency ultrasound imaging system

B-mode

beamforming, 223–224

imaging system hardware, 221–223

ultrasound imaging, see Ultrasound imaging

challenges

hardware specifications, 226

low-voltage high-frequency transducer, 225

system architecture, 227–229

CMUT, 219

conventional system's size, 218

Penn State

A/D converters, see Analog-to-digital converters (ADCs)

configuration, 229–230

experimental results, 246–249

receiver, 230–235

SRAM, see SRAM

transmitter, see Transmitter

silicon surface detection, 218

SonicWindow, 219

ultrasound ASIC chips, 218–219

Position-sensitive APDs (PSAPDs), 384–385, 395

Position-sensitive PMT (PS-PMT)

MA-PMT, 291–292

PET detector configuration, 292

Positron emission tomography (PET); see also Thoracic PET/CT

Argus PET/CT system, 128, 137

detectors, see PET detectors

drug development, 110

micro-CT systems, designs, 111

PET/CT, see Thoracic PET/CT

radioisotope, local activity density, 273

statistical methods, 132

Powell's method, 639

PPL, see Phase locked loop (PPL)

Preamplifier, 222

Preconditioned conjugate gradient (PCG), 440, 452, 453

Primary diffusion direction (PDD)

description, 541

FACT and TEND approaches, 549

probabilities, 552

statistical bootstrap, 553

Principal component analysis (PCA), 671

Probabilistic tractography

Bayesian formulations, 552

description, 550–551

diffusion profile, 552

heuristic approaches, 552

limitations, 553

Markov chain Monte Carlo (MCMC), 551

statistical bootstrap, 552–553

Projection-space material decomposition, 158–159

Prototype experimental board, 246

PSAPDs, see Position-sensitive APDs (PSAPDs)

PSF, see Point spread function (PSF)

PSNR, see Peak-Signal-to-Noise Ratio (PSNR)

PS-PMT, see Position-sensitive PMT (PS-PMT)

Pulse-echo experiments

Pitch-Catch mode experimental setup, 248

test results, 249

Pulse height spectrum (PHS), 99, 100

Q

QN methods, see Quasi-Newton (QN) methods

QSCA, see Quadratic surrogate and coordinate ascent (QSCA)

Quadratic surrogate and coordinate ascent (QSCA)

non-SQS function, 447–448

optimal curvature, 447

Poisson log-likelihood function, 446

Quasi-Newton (QN) methods, 638

R

Radial basis functions (RBFs), 624

Radiation detectors

fiber-optic coupling, 379–380

photodiodes, 380–388

scintillation detectors, 379

solid-state detectors, 388–390

Radiation dose

acquisition protocols, 139

coronal image, 139

maximum intensity projection image, 139, 140

measurement, 139

soft-ware and hardware tools, 138

Radionuclide transmission imaging, 361

Radiotracers, 349

Random coincidences (R), see Random counts

Random counts

coincidence events, detection, 289

ENF and, 289

narrow timing window, 288

NEC curve, 290

NECR formulation, 289–290

in PET, 302–303

timing resolution, 289

RBFs, see Radial basis functions (RBFs)

Receiver

amplified signals, VGA functioning, 234

bandwidth, 230–231

circuit design details, 231–235

design automation, 237–241

dynamic range, 231

effective bit resolution, 235

Gilbert-type four-quadrant multiplier, 233, 234

preamplifier, 231–232

protection devices, 225

required specifications, 230–231

transceiver chip gain and dynamic range requirements, 232

Regions-of-interests (ROIs)

brain, 611

CT method, 597–598

functional connectivity, 596

network connectivity, 612–613

perturbation, 614

placement, 580–581

seed-based method, 597

sparse methods, 600–601

Respiratory artifacts, thoracic PET/CT

attenuation correction, 404–405

breathing instruction, 407–410

CT protocols, 410–414

deconvolution techniques, 421–422

description, 403

gamma rays, 404

gated 4D PET/CT, see Gated four-dimensional (4D) PET/CT

lung carcinoma lesions, 405, 406

Rician noise, 536–537

ROI, see Regions-of-interests (ROIs)

Rotary echo spin-lock (SL) pulse

B₀ inhomogeneities, magnetization evolution, 575

longitudinal magnetization, 576

structure, 574–575

T_1rho-weighted contrast, 575

Row-column (RC), 267–268

R_1rho relaxation rate, 583

S

SAR, see Specific absorption rate (SAR)

Scatter coincidences (S), see Scatter counts

Scatter counts

Compton scattering, 286

energy spectrum generation, 287

finite energy window, 285

full energy peak, 287

intercrystal scatter, 286

in PET, 303

representation, 285

scatter corrections, 288

scatter fraction (SF), 287

Scintillators

configurations, alternative photodetector

APDs matrices, 294

depth-of-interaction, estimation, 296

DOI error, 296

drawback, 295

efficiency, 295–296

monolithic crystals, 295

one-to-one coupling, 294

small animal, 296

spatial resolution issue, 295

detectors

advantages, 379

Compton effect, 369

high-energy gamma ray, 368

high light output, 368

inorganic crystalline material, 368

PET scintillators, 368

properties, 368

radionuclide imaging, 368

effective atomic number, 277

gamma-ray detectors, 277

inorganic, characteristics, 278

light yield, 277

photodetector coupling, 277

SDF, see Signed distance function (SDF)

SD-OCT, see Spectrometer-based spectral domain OCT (SD-OCT)

Segmentation representation, MIS

explicit contour model, 668

fully automatic segmentation, 680

graph methods, 669–670

SDF, 669, 670, 679

T-snakes and T-surfaces, 669

vessels, 670

Semiconductor detectors, medical imaging

amorphous selenium detectors, 90

description, 89–90

indirect and direct conversion detectors, 91–94

intrinsic energy resolution, 105

signal transport processes

anode signals, 97

CST model, 94, 95

direct conversion detector, 96–97

indirect conversion detector, 94, 96

spatial resolution

MTF, 97–99

pixel pitch, 97

SPECT, CT and radiography, 89, 90

spectral resolution

counting direct conversion detectors, 103–105

DRF, see Detector response function (DRF)

integrating indirect conversion detectors, 102–103

nuclear physics and medical imaging, 99

PHS, 99, 100

tungsten tube spectra, 99, 100

Semiconductor photodetectors

APDs, 292

characteristics comparison, 294

continuous slab solution, 292

GAPD cells, 292–293

SiPM, 292–293

Sensitivity encoding (SENSE), MRI reconstruction

brain data, 506

coil sensitivity parameters, 502

description, 500, 524–525

ex vivo and in vivo images, rat's spinal cord, 506

iSENSE method, see iSENSE method

JSENSE, see Joint image reconstruction and sensitivity estimation in SENSE (JSENSE)

least squares optimization, 500–501

polynomial coefficients, 502

rank-deficient matrices, 503–504

sensitivity maps and decay of singular values, 503

SparSENSE and NNSENSE, 501

sum-of-squares method, 506–507

TV regularization, 502

Separable quadratic surrogate (SQS) algorithm, 448–449

Shallow breathing CT, 407

Short-time Fourier transform (STFT), 55–57

Signal-to-noise ratio (SNR)

cross-contamination, 165

iodine, 163

material density image, 164

significant improvement, 164–165

two-pass algorithm, 165, 167–168

water density image, 165, 166

Signed distance function (SDF), 669, 670, 679

Silicon photomultiplier (SiPM), 292–293

Simultaneous acquisition of spatial harmonics (SMASH), 499

Single-crystal layer/dual-ended photodetectors, 314–315

Single photon emission computed tomography (SPECT), 110, 111, 128, 132, 137, 208–210

Singular value decomposition (SVD), 493, 498

SiP, see System in package (SiP)

SiPM, see Silicon photomultiplier (SiPM)

SiPM devices

digital, see Digital SiPM

operation, 321–323

Slow CT, 410–411

Small 2D array

catheter-based CMUT system, 264

CMUT catheters, growth rate, 264

IVUS and ICE, 263–264

microlinear catheter, 265

real-time volumetric imaging, 265

ring array designs, 264

SMASH, see Simultaneous acquisition of spatial harmonics (SMASH)

Smoothness regularization, MIR

diffusion and curvature, 628

elastic regularization, 629–630

Sobolev semi-norm, 627–628

spatial transformation, 627

TPS model, 628–629

viscous-fluid-based model, 630

SNR, see Signal-to-noise ratio (SNR)

SoC, see System on a chip (SoC)

SOCT, see Spectroscopic OCT (SOCT)

Software registration, 349–351

Solid-state detectors

CdTe and CdZnTe, 388–390

Si(Li) and Ge(Li), 388

Sparse array, 266, 267

Sparse modeling, MRI reconstruction

Cartesian sampling

Haar wavelets, 492

NMSE, 492–493

rat (spine), brain and phantom, 492

reconstructed images, 493, 494

description, 488–489

l_p-norm minimization, 489

orthogonal and redundant wavelets, 491

signal models, 489–490

total variation (TV) minimization, 490

wavelet transform coefficients, 489

Spatial transformations, MIR

description, 623

linear and nonlinear models

DFT and DCT, 625

FFDs, 624–625

misalignment, images, 625–626

RBFs, 624

terminologies, 623

Specific absorption rate (SAR)

compressed sensing, 579

definition, 578

partial k-space acquisition approach, 579

reduction, spin-lock frequency, 579

spine and cartilage T_1rho imaging, 579–580

spin-lock times (TSLs), 579

U.S. FDA, 578

SPECT, see Single photon emission computed tomography (SPECT)

Spectral projected gradient L1 (SPGL1), 496, 498

Spectrometer-based spectral domain OCT (SD-OCT), 29

Spectroscopic OCT (SOCT), 54–56, 68

SPGL1, see Spectral projected gradient L1 (SPGL1)

Spin-lock radiofrequency (RF) pulse

B₁ and B₀ insensitive composite spin-lock pulse, 572–573, 576–577

Dixon's composite spin-lock pulse and phase cycling, 577–578

magnetization

evolution, 568, 573–574

preparations, 568

MRI hardware, 572

nominal and true spin-lock pulse strength, 572, 573

normal spin-lock pulse, 568, 574

rotary echo SL pulse, 574–576

T_1rho-weighted contrast, 569–570

SQS algorithm, see Separable quadratic surrogate (SQS) algorithm

SRAM

capacity, 241

clock modulation, simulation results, 243

design details, 241–243

functional block diagram, 242

measured outputs, 243

on-chip memory, 241

required specifications, 241

SS-OCT, see Swept-laser-based swept-source OCT (SS-OCT)

SSV technique, see Systematic size variation (SSV) technique

STFT, see Short-time Fourier transform (STFT)

Streamline tractography

FACT and TEND approaches, 549

limitations, 550

multitensor models and HARDI, 550

Runge–Kutta method and PDD, 548–549

SVD, see Singular value decomposition (SVD)

Swept-laser-based swept-source OCT (SS-OCT), 29

Synthetic array, 266–267

System architecture, 228–229

Systematic size variation (SSV) technique, 237

System in package (SiP), 19–21

System on a chip (SoC)

component integration, 19, 20

IC, 19, 20

implementing digital circuits, 20

programmable processors, 21

single-chip calculator, 19

T

Target registration error (TRE), 648

TD-OCT, see Timedomain OCT (TD-OCT)

Telecommunications complements medical imaging, 7–9

TEND approach, see Tensor deflection (TEND) approach

Tensor deflection (TEND) approach, 549

TFT, see Thin-film transistor (TFT)

Theory of compressed sensing (CS), 486–488

Thin-film transistor (TFT), 118, 122

Thin-film ultrasound transducer array

CMOS transceiver chip specifications, 247

PZT layers, 246

SEM image, 247

Sol-gel and multilayer dry-etching, 247

Thin-plate-spline (TPS) model, 624, 625, 628–629, 634, 646, 647

Thoracic PET/CT

breathing instruction-based methods, 407–410

CACT, 411–413

gated 4D, see Gated four-dimensional (4D) PET/CT

IACT, 413–414

low-pitch CT, 411

slow CT, 410–411

Timedomain OCT (TD-OCT), 27–28

Time-of-flight PET (ToF PET)

Cherenkov radiators, 318

conventional PET, 318

SNR improvements, 318

Timing window, 278–279

TIQ comparator, 235–237

ToF PET, see Time-of-flight PET (ToF PET)

Tomographic image reconstruction, 131–132

TPS model, see Thin-plate-spline (TPS) model

Tracer kinetic analysis, PET and SPECT

compartmental model

blood flow, 465–467

glucose metabolism, 467–468

receptor-ligand binding, 468–471

noncompartmental model

description, 471

graphical analysis, 471–472

spectral analysis, 473

parameter estimation and parametric images

LLS, 476–481

NLS, 474–475

procedures, 464

purpose, 463–464

standard kinetic parameters, 464

Transmitter

beam focusing, programmable delays, 245

CMOS technology, 244

delay time, 244

dynamic focusing and steering delay, 244

focused signal, expression, 243

transmit pulses, 245

TRE, see Target registration error (TRE)

T_1rho MRI

applications

AD and PD, 583–584

BDL and carbon tetrachloride intoxication, 584–585

BT4C glioma animal model, 586

cerebral ischemia, T_1rho dispersion, 584

intervertebral disc and articular cartilage, 580–583

murine radiation–induced fibrosarcoma model, 586

myocardial infarction (MI), 586

and T₂ relaxation times, 581–582

tumors, 585–586

Bloch–McConnell equations, 571

CEST, 571–572

description, 586–587

dispersion, 570–572

mapping, 570–572

proton exchange, 571

SAR, see Specific absorption rate (SAR)

spin-lock RF pulse, see Spin-lock radiofrequency (RF) pulse

T₁ and T₂ relaxation time

CT, x-ray and nuclear medicine, 565–566

Larmor frequency, 566

low-frequency motional processes, 567

precession rate, spins, 567

spin–lattice relaxation rate, 566

spin-lock pulse field strength, 566–567

weighted contrast imaging, 570–572

True coincidences (T), 302

Truncation, 344–345

U

Ultrasound imaging

axial resolution, 221

beam width, 220–221

reflection, 220

resolution, 220

V

Voltage-sensitive preamplifier(VSA), 372–374

VSA, see Voltage-sensitive preamplifier(VSA)

W

Windmill artifacts, 211–212

X

X-ray micro-CT systems

CCD, 110, 140

components

angular position, 124

constant radiation level, 122

flat-panel detector, 124–125

mechanical subsystem, 126

minimal beam collimation, 125

pixel size and geometrical configuration, 122

rotating gantry, 123

scanner design, 123

source output window, 125

data acquisition, see Data acquisition, micro-CT systems

description, 111

evaluation

quality, reconstructed images, 136–138

radiation dose, 138–140

X-ray flat-panel detector, 133–136

geometrical configuration, 126–128

high-resolution imaging, 141

PET and SPECT images, 110

small-animal

anesthesia equipment/vital sign monitoring devices, 112

configuration, in vitro, 112

fast and sensitive detectors, 113

in vivo requirements demand, 112, 113

image quality and radiation delivery, 111

photon-counting detectors, 113–114

tomographic image reconstruction, 131–132