Avaliação por imagem da paralisia de pregas vocais

Abstract

Paralisia das pregas vocais é causa frequente de rouquidão, podendo ser secundária a várias lesões ao longo do trajeto do X par craniano e seus ramos, particularmente os nervos laríngeos recorrentes. Apesar de grande parte dos casos ser idiopática, os métodos de imagem são muito importantes na pesquisa de fatores etiológicos, tais como lesões neoplásicas da tireoide e esôfago com invasão secundária dos nervos laríngeos recorrentes. Além destas, outras anormalidades como aneurismas do arco aórtico e da artéria subclávia direita podem ser encontradas. É fundamental que o radiologista conheça a anatomia pertinente a esta região e as principais afecções que podem ocorrer, para que o estudo seja corretamente planejado, auxiliando o diagnóstico e o planejamento terapêutico. Além disso, como até 35% dos casos de paralisia da prega vocal são assintomáticos, o conhecimento dos sinais radiológicos que indicam esta condição é indispensável, cabendo ao radiologista alertar o médico assistente sobre os achados do exame. Neste trabalho realizamos uma revisão da anatomia e das principais doenças responsáveis pela paralisia de cordas vocais, demonstrando-as por meio de estudos de tomografia computadorizada e ressonância magnética de casos típicos. Mostramos, também, as alterações radiológicas próprias da laringe que indicam a presença de paralisia das pregas vocais.

Voice and swallowing implications in patients with tumors in their mediastinum

“…Reflex cough during and after swallowing is the classic mechanism of defense of oropharyngeal dysphagia 20,21 . In the study, it was possible to identify the frequency of this symptom in ten study subjects.…”

Characteristics of voice and personality of patients with vocal fold immobility

“…Numerous risk factors are attributed to the vocal fold immobility, such as central and peripheral nervous systems disorders, the latter being the most common one, besides aging, neck trauma, head and/or chest, intubation, diabetes mellitus, hypertension, surgical injuries, cancer, heart diseases, toxic, metabolic, inflammatory, and idiopathic which affect the vagus nerve, some of its branches or both (4,15,16) . As seen, many are the diseases that may affect the vagus nerve and, consequently, the activities that require the laryngeal functions: breathing, protection, and phonation.…”

“…The vagus nerve is originated in the nuclei located in the bulb and extends from the brain stem to the abdomen, originating the superior and inferior laryngeal nerve, named recurrent laryngeal right and left nerve, responsible for supplying all the intrinsic laryngeal muscles but the cricothyroid muscle, innervated by the external superior laryngeal nerve (15)(16)(17) . Therefore, the vagus nerve and its ramifications may undergo some injuries at any part of its pathway, resulting in the vocal fold immobility; however, the left recurrent laryngeal nerve has higher chance of being injured, due to its longer pathway (18) .…”

“…The vocal deviation degree of patients with vocal fold immobility depends on the position of the paralyzed vocal fold, on the atrophy and laxity of the vocal fold, as well as on the surpassing of the healthy vocal fold and the constriction of the larynx (18) . In bilateral vocal fold immobility, the voice is characterized as high pitched, because of the paramedian position of both vocal folds, and the individual may have respiratory problems due to pneumonia and frequent aspirations (4,15) . In the unilateral immobility of the vocal fold, the patient may evolve with pneumophonoarticulatory incoordination, weak voice, increase of effort to speak, vocal fatigue, roughness, reduction of intensity and vocal extension, increase of fundamental frequency, little projection, tension, maximum time of reduced phonation, breathiness, and dysphagia (4) .…”

“…However, the roughness is mentioned as one of the most common symptoms between patients with vocal fold immobility; however, 35% of these patients may have no symptoms (15,18) , an so it may be considered as just a symptom of a greater involvement.…”