MRI of the Body

As with the introduction of x -ray computed tomography, much of the initial development of magnetic resonance applications tended to focus on the central nervous system. The development of magnetic resonance imaging applications to other organ systems such as the chest, abdomen, pelvis and extremities has lagged somewhat behind, awaiting technical improvements, and a broader user base. The past two years have seen a marked increase in imaging applications throughout the body, most notably the musculoskeletal system. It is in this regard, that MRI of the Body is a welcome arrival as a text which describes both basic principles of magnetic resonance ima­ ging and surveys the current status of magnetic resonance imaging applications throughout the body. The volume is concise, focused, clinically oriented, and abun­ dantly illustrated. In each organ system, the appropriate technical approach is discussed, the normal anatomic features are reviewed, and the range of pathologic appearances which may be encountered are described. The authors of the chapters provide a balanced overview of MR applications and describe both present limitations and future potential of magnetic resonance imaging applications in the organ system described.

Physical basis.- Physical basis of nuclear magnetic resonance.- The magnetization of matter.- Elementary magnetic momentum and local magnetization.- Effect of a homogeneous, stable external magnetic field.- Components of nuclear magnetization.- Nuclear magnetic resonance.- Return of nuclear magnetization to equilibrium.- Signal parameters.- The nuclear magnetic resonance signal.- Pulse sequences.- Formation of an image.- Magnetic field gradients.- Signal location.- Imaging method with two-dimensional Fourier Transform (2D-FT).- Fast imaging methods.- Contrast media.- Chemical shift.- Flow in imaging.- Practical progress of an MRI examination.- Artifacts.- System-specific artifacts.- Influence of the basic characteristics.- Influence of system quality.- Patient-specific artifacts.- Artifacts common to all patients.- Artifacts peculiar to given patients.- Quality control.- Definition of QC parameters.- Basic parameters.- Complementary parameters.- Test substances and test objects.- Test substances.- Test objects.- NMR spectroscopy from experimental to clinical spectroscopy.- Principle of NMR spectroscopy.- Chemical shift.- Spectrum quantification.- Most significant results of spectrocopy in man.- Spectroscopy of Phosphorus 31.- Spectroscopy of other nuclei.- Clinical application.- Localization of the spectrum.- Magnetic field homogeneity.- Conclusion.- Contrast media.- Theoretic basis.- Paramagnetic substances.- Superparamagnetic substances.- Effects on contrast.- Paramagnetic ions.- General points.- Physicochemical, pharmacokinetic and toxicological properties of simple gadolinium complexes.- Imaging considerations.- Other contrast media.- Other intravascular products.- Oral contrast agents.- Inhaled contrast agents.- Experimental models.- Clinical applications.- Neurological applications-brain.- Other applications.- Conclusion.- Head and neck.- Facial structures — nasopharynx and parapharyngeal spaces.- Technique.- Normal anatomy.- Pathology.- Limitations.- Superficial soft tissue (excluding the orbits) : parotid gand and temporomandibular joint.- The parotid gland.- Temporomandibular joint.- Buccal cavity and the oropharynx.- Technique.- Anatomy.- Pathology.- Limitations.- Cervical region.- Pharynx and larynx.- Thyroid and parathyroid glands.- The vascular grooves.- Cervical soft tissue — the thoracic inlet.- Conclusion.- Thorax.- Exploration techniques.- Choices of TR.- Choice of TE.- Other parameters.- Section orientation.- Cardiorespiratory gating.- Other techniques.- Normal anatomy.- Mediastinum.- Hili of the lungs.- Pulmonary parenchyma.- Pleura.- Thoracic wall.- Diaphragm.- Pathological findings.- Mediastinal masses.- Aortic pathology.- Hilar masses.- Pulmonary vascular pathology.- Lung pathology.- Pleura and thoracic wall pathology.- Conclusion.- Heart.- General points.- Examination techniques.- Adverse effects — contraindications.- Study of the heart.- Cardiac cycle.- Imaging sequences and normal findings.- Choice of section planes.- Clinical applications.- Breast.- Imaging technique.- MR image of the normal breast.- Results.- Technical aspects.- Benign pathology.- Malignant pathology.- Conclusion.- Liver, biliary tract, portal system, spleen.- Technique.- Sequences.- Contraindications.- Preparation.- Normal anatomy.- Clinical findings.- MRI of the liver.- MRI of the biliary tract.- MRI of the portal system.- MRI of the spleen.- Conclusion.- Pancreas.- Application of MR imaging techniques to the pancreas.- Normal pancreas.- Acute and chronic pancreatitis.- Liquid collections and pseudocysts.- Pancreatic hemorrhage.- Tumors of the pancreas.- Metabolic diseases.- Vascular abnormalities associated with hepatic diseases.- Present situation, prospects, comparison with CT.- Tissue characterizarion.- Gastrointestinal tract.- MR examination technique for the GI tract.- General preparation of the patient.- Contrast media.- Patient position.- Body coils and surface coils.- Imaging parameters.- Normal anatomy of the rectum.- Abnormalities of the GI tract.- Crohn’s disease.- Rectal and colonic tumors.- Extramural signs.- Invasion of neighboring organs.- Adenopathy.- Tumor recurrence.- MR signs of reccurence.- Tissue characterization.- Advantages and disadvantages of MR — Future prospects.- The kidneys and perirenal space.- Technique.- Anatomy.- Mass lesions.- Cystic lesions.- Solid lesions.- Loss of corticomedullary differentiation.- Transplanted kidneys.- Perirenal lesions.- Collections.- Retroperitoneal fat.- Paramagnetic substances.- Adrenal glands.- MRI procedure.- Normal anatomy.- Secretory tumors of the adrenals.- Conn’s disease.- Pheochromocytoma.- Adrenal hyperplasia — Cushing’s disease.- Non-secretory tumors.- Metastases.- Nonhyperfunctioning adenomas.- Other lesions.- Cysts.- Myelolipoma.- Neuroblastoma.- Hematoma.- Adrenal carcinoma.- Contribution of spectroscopy imaging to adrenal investigation.- Conclusion.- Large retroperitoneal blood vessels.- Exploration technique.- Normal findings.- Abdominal aorta and its visceral branches.- Appearance of the inferior vena cava.- Spatial resolution of MRI.- Pathological findings.- Aneurysm of the abdominal aorta.- Aortic dissections.- Periaortic pathology and retroperitoneal fobrosis.- Atheromatous disease.- The vena cava.- Conclusion.- Retroperitoneal adenopathy.- Technique.- Sequences.- Section plane.- In practice.- Findings.- Conclusion.- Gynecology.- Examination technique.- Normal anatomy.- Uterus.- Vagina.- Ovaries and adnexa.- The genital vessels.- The lymph nodes.- Benign pathology.- Uterus.- Ovaries.- Other pathology.- Malignant pathology.- Carcinoma of the uterine body.- Cancer of the cervix.- Pelvic recurrence of uterine cancer.- Malignant ovarian tumors.- Other gynecological tumors.- Adenopathy.- Postoperative pathology and therapeutic follow-up.- Conclusion.- Male pelvis.- Technique.- Patient preparation.- Imaging parameters.- Normal anatomy.- Pelvic wall.- Pelvic contents.- Pathology.- Bladder pathology.- Postoperative pathology (tumor recurrence, infectious diseases).- Lymph node pathology.- Bone metastases.- Conclusion.- Pathology of the scrotum.- Examination technique.- Normal appearance.- Pathology of the scrotum.- Mass lesions of the testes.- Inflammatory pathology : orchiepididymitis.- Traumatic pathology.- Other pathological conditions.- Conclusion.- Joints.- General technical points.- Pulse sequences.- Coils.- Parameters influencing image quality.- Section plane and thickness.- Position of the patient.- Examination procedure.- Tissue characterization in the different sequences.- Windows.- Normal images.- Shoulder.- Elbow.- Hand and wrist.- Hip and sacroiliac joint.- Knee.- Ankle and foot.- General findings.- Liquid effusion.- Cartilages.- Subchondral bone.- The synovial membrane.- Ligaments and tendons.- Muscles.- Pathological conditions.- Trauma.- Infection and arthritis.- Osteonecrosis.- Sympathetic reflex dystrophy.- Arthrosis and mechanical dystrophy.- Primary synovial osteochondromatosis.- Periarthritis.- Metabolic arthropathy.- Periarticular soft tissue disease and other pathogical conditions.- Spine.- Technical considerations.- Surface coils.- Spatial resolution and signal-to noise ratio.- Choice of the sequences.- Limitation of motion artifacts.- Choice of the section planes.- Normal images.- Lumbar spine.- Dorsal spine.- Cervical spine.- Degenerative pathology.- Lumbar level.- Cervical level.- Infections of the disk and of the vertebra.- Spondylolysis and spondylolisthesis.- Trauma.- Detection of epidural hematomas.- Bone lesions.- Disk lesions.- Ligamentous lesions.- Detection of spinal cord lesions.- Inflammatory pathology.- Post-treatment appearance of the spine.- Post-surgery.- Post-chemonucleolysis.- Post-radiation therapy.- Spinal tumors.- Benign tumors.- Malignant spine tumors.- Conclusion.- Primary musculoskeletal tumors.- Advantages and limitations of MRI.- Advantages.- Limitations.- Technique.- Contribution of MRI to diagnosis.- Assessment of tumor extension.- Intramedullary extension of bone tumors.- Soft tissue extension.- Vessels.- Intraarticular expansion.- Treatment efficacy.- Post-treatment checkup.- Practical examples.- Osteosarcoma.- Ewing’s sarcoma.- Chondrosarcomas.- Chordoma and other sacral tumors.- Other primitive malignant bone tumors.- Soft-tissue tumors.- Conclusion.- Bone Marrow: MRI of diffuse and multifocal bone marrow malignancy.- Technique.- Normal bone marrow.- Pathological bone marrow.- Low-signal marrow.- High-signal marrow.- Multifocal bone marrow disease.- Conclusion.- Role of MR in non-oncologic pediatric imaging.- Technique.- Indications.- Discussion.- Conclusion.- MRI in pediatric oncology.- Material and techniques.- Tumoral pathology.- Neuroblastoma.- Nephroblastoma.- Non-Hodgkin lymphoma (NHL).- Rhabdomyosarcoma and soft-tissue sarcomas.- Hepatoblastoma.- Hodgkin’s disease.- Conclusion.- Obstetrical MRI.- The mother.- MRI pelvimetry.- Lumbar spine in pregnant women.- Uterus.- Trophoblastic tumors.- The fetus.- General points.- Appearance of the major organs.- Other intrauterine structures.- Application of MRI to radiation therapy.- Contribution of MRI to radiation therapy planning.- Geometric distortion.- Gradient calibration.- Distortion in multiple-slice mode.