Main description:

MRI is assuming a dominant role in imaging of the larynx. Its superior soft tissue contrast resolution makes it ideal for differentiating invasion of tumors of the larynx from normal or more sharply circumscribed configuration of most of the benign lesions. Over ten years ago CT made a major impact on laryngeal examination because it was the first time that Radiologists were beginning to look at submucosal disease. All of the previous examinations duplicated the infor mation that was available to the clinician via direct and in-direct laryngo scopy. With the advent of rigid and flexible endoscopes, clinical examination became sufficiently precise that there was little need to perform studies such as laryngography which merely showed surface anatomy. The status of deep structures by these techniques was implied based on function. Fortunately laryngography is now behind us together with all of the gagging and contrast reactions which we would all like to forget. CT is still an excellent method of examining the larynx but it is unfortunately limited to the axial plane. With presently available CT techniques motion deteriorates any reformatting in sagittal or coronal projections. The latter two planes are extremely helpful in delineating the vertical extent of submucosal spreads. MRI has proven extremely valuable by producing all three basic projections, plus superior soft tissue contrast. Although motion artifacts still degrade the images in some patients, newer pulsing sequences that permit faster scanning are elimi nating most of these problems.

Contents:

1: General Aspects of Laryngeal Cancer.- 1. Introduction.- 1.1. Incidence.- 1.2. Predisposing factors.- 2. TNM staging.- 2.1. Introduction.- 2.2. Clinical classification.- 3. Diagnostic aspects.- 3.1. History.- 3.2. External examination.- 3.3. Laryngoscopy.- 4. Therapeutic options.- 4.1. Radiotherapeutic options.- 4.1.1. Technique.- 4.1.2. Prognostic factors of irradiation treatment.- 4.1.3. Complications due to radiation therapy.- 4.2. Surgical options.- 4.2.1. Laser therapy and microsurgical stripping.- 4.2.2. Laryngofissure and cordectomy.- 4.2.3. Vertical partial laryngectomy.- 4.2.4. Antero-frontal laryngectomy for excision of the anterior commissure.- 4.2.5. Supraglottic laryngectomy.- 4.2.6. (Wide-field) total laryngectomy.- 4.3. Chemotherapeutic options.- 5. Therapeutic management.- Tl- and T2-glottic carcinomas.- T1- and T2-subglottic carcinomas.- T2- and T2-supraglottic carcinomas.- T3- and T4-laryngeal cancer.- Nodal metastasis.- References.- 2: The Patterns of Growth And Spread of Laryngeal Cancer.- 1. Introduction.- 2. Spread of cancer in various regions.- 2.1. Cancer of the supraglottic region.- 2.2. Cancer of the glottic region.- 2.3. Cancer of the subglottic region.- 3. Cartilage invasion.- 4. Lymphatic spread.- 5. Vascular and perineural invasion.- References.- 3: The Radiological Examination of the Larynx.- 1. Introduction.- 2. Phonation manoeuvers.- 3. Frontal tomography.- 4. Contrast laryngography.- 5. Computed tomography.- 6. CT versus conventional radiological techniques.- 6.1. CT versus conventional tomography.- 6.2. CT versus contrast laryngography.- References.- 4: General Aspects of MR Imaging.- 1. Introduction.- 2. Technical principles.- 2.1. Properties of atomic nuclei.- 2.2. Resonance.- 2.3. Behaviour of a sample of nuclei.- 2.4. Proton density, tissue characteristics.- 2.5. Spin echo technique.- 3. The equipment.- 3.1. Magnet.- 3.2. Gradient system.- 3.3. Coils.- 3.4. Computer.- 4. Disadvantages of MR imaging.- 4.1. Claustrophobia.- 4.2. Contra-indications.- References.- 5: MR Imaging Techniques of the Larynx.- 1. Surface coils.- 1.1. Coil selection.- 2. Parameters.- 2.1. Pulse sequences.- 2.2. Slice thickness.- 2.3. Slice direction.- 2.4. Matrix size.- 2.5. Number of signal measurements.- 3. Artifacts.- 3.1. Motion artifacts.- 3.2. System artifacts.- 3.3. Chemical shift artifacts.- 3.4. Artifacts due to ferromagnetic implants.- 4. Performance of the laryngeal examination.- References.- 6: MR Imaging of the Normal Larynx.- 1. Introduction.- 2. MR imaging of laryngeal structures.- 2.1. Laryngeal skeleton.- 2.2. Laryngeal compartments.- 3. Landmarks.- 3.1. Hyoid bone.- 3.2. Aryepiglottic fold.- 3.3. False vocal cords.- 3.4. True vocal cords.- 3.5. Subglottic level.- References.- 7: MR Imaging of Laryngeal Cancer.- Abstract.- 1. Introduction.- 2. Materials and methods.- 3. Case reports.- Case 1.- Case 2.- Case 3.- Case 4.- Case 5.- Case 6.- Case 7.- 4. Discussion.- 5. Conclusions.- References.- 8: MR imaging of Normal and Cancerous Laryngeal Cartilages. Histopathological Correlation.- Abstract.- 1. Introduction.- 2. Materials and methods.- 3. Results.- 3.1. Epiglottic cartilage.- 3.2. Thyroid cartilage.- 3.3. Cricoid cartilage.- 3.4. Arytenoid cartilage.- 4. Discussion.- 5. Conclusions.- References.- 9: Dagnosis of Laryngeal Cartilage Invasion by Cancer. Comparison of CT and MR Imaging.- Abstract.- 1. Introduction.- 2. Materials and methods.- 2.1. Imaging techniques.- 2.2. Image interpretation.- 2.3. Pathological findings.- 3. Results.- 3.1. Epiglottic cartilage.- 3.2. Thyroid cartilage.- 3.3. Arytenoid cartilage.- 3.4. Cricoid cartilage.- 3.5. Group of patients for which no pathologic correlation was available.- 3.6. Movement artifacts.- 4. Discussion.- 4.1. Elastic cartilage: epiglottic cartilage.- 4.2. Hyaline cartilage: thyroid, cricoid and arytenoid cartilages.- 5. Summary.- References.- 10: MR Findings of Cartilage Invasion by Laryngeal Cancer. Value in Predicting Outcome of Radiation Therapy.- Abstract.- 1. Introduction.- 2. Materials and methods.- 3. Results.- 4. Discussion.- References.- 11: General Discussion.- References.