In addition to triggered MR techniques, which are all quite laborious, few publications exist which use ‘real-time’ imaging, mainly using spoiled gradient-echo sequences or echo-planar-imaging. The main advantages of MRI in this context, however, are that it allows real-time dynamic imaging of moving structures with adequate temporal resolution and also allows the radiologist to choose adequate imaging planes beyond the axial orientation.Ī small series of MRI studies has been published on the potential of this modality in the assessment of the vocal tract. Theoretically, at least, MRI provides better tissue contrast as well as sufficient spatial resolution for visualization of the vocal cords. Like CT scan, MRI enables the examiner to visualize pathological changes beneath the surface of the larynx and, for example, discover a tumor in the soft tissue or estimate the depth of invasion of a malignant process. Some of these studies have shown that coronal reconstruction of images acquired during ‘hee’ phonation could improve the detection rate of vocal cord palsy. Studies have been conducted that have used sequential scans during different phonations. In adults, however, specific examination of the vocal cords using USG may be hampered by echoes caused by laryngeal calcifications and air–tissue borders.ĬT scan is usually used for assessing tumor extent or for the presence of anatomic variants of vessels or nerve courses and can also be used for virtual laryngoscopy. In cases of vocal cord palsy USG is often used to look for underlying causes such as tumors. The search for underlying pathologies must then be performed by means of other techniques. While fluoroscopy provides real-time images of the vocal cords during different phonations, it does not display the surrounding anatomy. Radiological fluoroscopic imaging has been used for decades as an alternative to endoscopy. Moreover, the procedure might be impossible to perform in some cases due to unfavourable anatomic conditions, abnormal emetic disposition, severely impaired general condition of the patient, or severe coagulopathy. Müller proposed that all cases of hoarseness lasting longer than 3 weeks must be evaluated by an otorhinolaryngologist to rule out malignant disease.Īlthough modern endoscopic devices are extremely flexible, the examination is nevertheless invasive successful endoscopy depends to a large extent on the patient's cooperation. However, this symptom may also be due to malignant tumours. Hoarseness is a common symptom in a variety of benign diseases for example, it may be due to infection and inflammation (e.g., common cold), vocal cord paralysis, or trauma.
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