Yang Xia - Essential Concepts in MRI

178 165

179 166

180 167

181 168

182 169

183 170

184 171

185 172

186 173

187 174

188 175

189 176

190 177

191 178

192 179

193 180

194 181

195 182

196 183

197 184

198 185

199 186

200 187

201 188

202 189

203 190

204 191

205 192

206 193

207 194

208 195

209 196

210 197

211 198

212 199

213 200

214 201

215 202

216 203

217 204

218 205

219 206

220 207

221 208

222 209

223 210

224 211

225 212

226 213

227 214

228 215

229 216

230 217

231 218

232 219

233 220

234 221

235 222

236 223

237 224

238 225

239 226

240 227

241 228

242 229

243 230

244 231

245 232

246 233

247 234

248 235

249 236

250 237

251 238

252 239

253 240

254 241

255 242

256 243

257 244

258 245

259 246

260 247

261 248

262 249

263 250

264 251

265 252

266 253

267 254

268 255

269 256

270 257

271 258

272 259

273 260

274 261

275 262

276 263

277 264

278 265

279 266

280 267

281 268

282 269

283 270

284 271

285 272

286 273

287 274

288 275

289 276

290 277

291 278

292 279

293 280

294 281

295 282

296 283

297 284

298 285

299 286

300 287

301 288

302 289

303 290

304 291

305 292

306 293

307 294

308 295

309 296

310 297

311 298

312 299

313 300

314 301

315 302

316 303

317 304

318 305

319 306

320 307

321 308

322 309

323 310

324 311

325 312

326 313

327 314

328 315

329 316

330 317

331 318

332 319

333 320

334 321

335 322

336 323

337 324

338 325

339 326

340 327

341 328

342 329

343 330

344 331

345 332

346 333

347 334

348 335

349 336

350 337

351 338

352 339

353 340

354 341

355 342

356 343

357 344

358 345

359 346

360 347

361 348

362 349

In the fall semester of 1994, I became a new assistant professor of physics at Oakland University, in the specialization of medical physics. After receiving my assignment to teach a graduate-level one-semester course in magnetic resonance imaging (MRI) for the next semester, I sat in my nearly empty office and wondered what and how to teach my students. As someone who had been working in MRI research for eight years at that time, I knew the importance of the fundamental theory. As someone who had been a hands-dirty experimentalist, I knew the importance of hardware and software that enabled any experiment. As someone who was specialized in quantitative MRI, I loved this field of research where the final result was an image, hopefully a beautiful and useful one. At the same time, I remembered my occasional regret during my imaging career that I did not know much about spectroscopy. I therefore determined to teach my students a little bit of nuclear magnetic resonance (NMR) spectroscopy.

I started to read the books that were available at the time, to find a potential textbook for my students. I wished I had read some of these books earlier, since there was so much that I simply didn’t know! As I went over these books for a possible adaptation for my course, I could not find any single book that contained what I had in my mind as the four essential and inseparable components of MRI – theory, instrumentation, spectroscopy, and imaging. There were books that were excellent and extensive in each of the four essential components in MRI. I was, however, unable to find one book that introduces all four components that I had in mind. (Asking my students to buy multiple books for one course was not an option.) I eventually realized, painfully, that I would have to put together the materials myself, if I wanted to teach the course as I had planned in my mind. My starting point was two excellent books that were available at that time: P.T. Callaghan’s Principles of Nuclear Magnetic Resonance Microscopy (Oxford University Press, 1991) and R.K. Harris’s Nuclear Magnetic Resonance Spectroscopy (Longman Scientific & Technical, 1989). I had the pleasure to communicate with both authors on their books during my teaching. My lecture notes, evolved and revised substantially during the last 26 years, became the basis for this book.

Since my course is for one 14-week semester, I must pick and choose what I could cover within that given time; I simply do not have time to cover all important concepts in all four components in great detail. I, however, determined to cover all four components of MRI: the theory of physics that explains this fascinating phenomenon, the instrumentation and experimental techniques that facilitate the execution of this fascinating phenomenon, the early adaptation of this physics phenomenon in the practice of NMR spectroscopy, and finally MRI. The requirements and time constraints of the course reflect the compromised (or optimized) choices, which are personal, for the topic selections in this book and the words “ Essential Concepts ” in the title of this book.

This book is grouped into five parts. Part I introduces the essential concepts in magnetic resonance, including the use of the classical description and a brief introduction of the quantum mechanical description. It also includes the description for a number of nuclear interactions that are fundamental to magnetic resonance. Part II covers the essential concepts in experimental magnetic resonance, which are common for both NMR spectroscopy and MRI. Part III describes the essential concepts in NMR spectroscopy, which should also be beneficial for MRI researchers. Part IV introduces the essential concepts in MRI. The final part is concerned with the quantitative and creative nature of MRI research. At the end of the book there are several short appendices, which include some background information on several topics in the book, some sample syllabi for possible ways to teach this course, as well as some homework problems.

I owe a great debt to the late Sir Paul T. Callaghan, who was my graduate advisor at Massey University in Palmerston North, New Zealand during 1986–1992. He taught me the art and science of NMR imaging at microscopy resolution (µMRI).

In my own research journey at Oakland University since 1994, I am very grateful for the beautiful works of my graduate students (Jonathan Moody, Hisham Alhadlaq, Jihyun Lee, Farid Badar, Daniel Mittelstaedt, David Kahn, Syeda Batool, Hannah Mantebea, Amanveer Singh, Austin Tetmeyer, Aaron Blanc), the mutual education of my former postdocs in MRI (ShaoKuan Zheng, Nian Wang, Rohit Mahar, Nagaraja Cholashetthalli), and the stimulating exchange of many visiting and sabbatical scientists to my lab (Paul T. Callaghan, Siegfried Stapf, Hisham A. Alhadlaq, Ekrem Cicek, RanHong Xie, ZhiGuo Zhuang, Zhe Chen). I have also benefited in my MRI research from the collaboration and interactions with many professional colleagues in MRI (Eiichi Fukushima, Kenneth Jeffrey, Gregory Furman, Jia Hua, Yong Lu, Quan Jiang, Jiani Hu, Craig Eccles, Mark Mattingly, Dieter Gross, Thomas Oerther, Volker Lehmann). Thank you.

I am grateful for four five-year R01 grants from the National Institutes of Health (NIH NIAMS) to my research lab at Oakland University, much internal support from the Research Excellence Fund in Biotechnology and the Center for Biomedical Research at Oakland University, the Department of Physics at Oakland University, and an NMR instrument endorsement from R.B. and J.N. Bennett (Oakland University), which initiated and supported my micro-imaging adventure at Oakland University.