Vocal Process Avulsion

Vocal process avulsion is a rare condition in which laryngeal trauma causes a separation of the vocal process from the body of the arytenoid cartilage. Typically symptoms are dysphonia and shortness of breath during phonation. Strobovideolaryngoscopy, laryngeal electromyography, and laryngeal computed tomography are helpful in establishing this important and sometimes elusive diagnosis. Several treatment modalities have been reported with varying success. We report four new cases, review four cases reported previously by the senior author, and suggest approaches to diagnosis and optimal treatment of vocal process avulsion.     

Vocal Process Avulsion

Vocal process avulsion is a rare complication of intubation or external laryngeal trauma that can cause significant dysphonia. The vocal process develops independently from the body of the arytenoid cartilage, which results in a fusion plane that is vulnerable to trauma. The findings of vocal process avulsion may be subtle, and the relationship of the vocal process to the body of the arytenoid cartilage must be examined closely. Stroboscopy is critical in the evaluation. We describe three cases of vocal process avulsion encountered by the senior author (R.T.S.) over the last 5 years and discuss our approaches to evaluation and treatment. All cases were repaired endoscopically. However, we used three different techniques. These include chemical tenotomy with botulinum toxin, closed reduction with fat injection, and open reduction via cordotomy.     

Permanent medialization of the paralyzed vocal fold utilizing botulinum toxin and Gelfoam

The clinical picture of a paralyzed vocal fold often has the same appearance as a subluxated arytenoid, with anterior and medial displacement of the arytenoid and a foreshortened and lax vocal fold. Previous work by the authors has shown that a subluxated arytenoid may be permanently repositioned by reduction and selective injection of the intrinsic laryngeal musculature with botulinum toxin. The injection changes the forces within the larynx, allowing the arytenoid to be brought back to proper position on the cricoid cartilage. This concept has been extended to the paralyzed vocal fold. It has been noted that even a clinically paralyzed vocal fold has voluntary motor units that may still act on the arytenoid through residual action from the interarytenoid and synkinesis. These forces are significant enough to manipulate the arytenoid and, thus, the vocal fold, into its correct, adducted position. In this paper, the arytenoid is mobilized to free any fibrosis. The thyroarytenoid and lateral cricoarytenoid muscles are then injected to prevent any forward synkinetic pull on the arytenoid. Next, a Gelfoam injection medializes the vocal fold to create glottic closure. This rebalancing sufficiently positions the arytenoid, so that valvular function is permanently restored. In the ten patients studied for over 1 year, there was a 90% success rate as measured by videostroboscopy, phonation time, and V-RQOL analysis. There were no untoward complications. All the materials used are nonpermanent. The procedure does not limit other techniques from being performed at a later time.     

Arytenoid dislocation

Arytenoid dislocation is a common yet infrequently diagnosed complication of laryngeal trauma. It may result in various symptoms, including permanent dysphonia, although immediate voice change is not always present. Early reduction is the treatment of choice; however, late reduction is often successful in restoring voice. A high index of suspicion based on the history of the patient is necessary to recognize arytenoid dislocation. Thorough physical examination and objective tests are helpful in confirming this diagnosis.     

Mild Vocal Fold Paresis: Understanding Clinical Presentation and Electromyographic Findings

The implications of mild vocal fold hypomobility are incompletely understood. This study describes the clinical, electromyographic, and probable etiologic findings in patients who presented with complaints of dysphonia and whose physical examination revealed vocal fold paresis as a factor possibly contributing to their voice complaints. A retrospective chart review of all patients who presented to a tertiary laryngology referral center over a 13-month period, who had a clinical diagnosis of mild vocal fold hypomobility and who underwent laryngeal electromyography, were included in the study. A total of 22 patients completed the medical evaluation of their voice complaint. Of these patients, 19 (86.4%) were found to have evidence of neuropathy on laryngeal electromyography. The clinical picture indicated the following probable origins for the vocal fold paresis: goiter/thyroiditis (7/22 or 31.8%), idiopathic (4/22 or 18.2%), viral neuritis (4/22 or 18.2%), trauma (3/22 or 13.6%), and Lyme's disease (1/22 or 4.5%). This article describes the clinical entity of mild vocal fold hypomobility and associated flexible laryngoscopic, rigid strobovideolaryngoscopic, and laryngeal electromyographic findings.     

Unilateral recurrent laryngeal nerve paralysis: A re-examination

Re-examination of flexible fiberoptic videotaped laryngeal images of 39 patients with unilateral recurrent laryngeal nerve paralysis (URLNP) by four observer-judges revealed consistent findings of a unilaterally appearing shorter vocal fold with asymmetry of the arytenoid complex on the involved side. No previous similar experience in otolaryngological training or practice has been encountered. Multiple discrepancies between and among observer-judges regarding vocal fold positions during phonation were encountered. Possible explanations are discussed. The need for further investigation to determine the mechanics causing these differences is stressed. It is suggested that for the present, such terms as median, paramedian, and intermediate be used in teaching and in practice as generalities only.     

Effects of long-term intubation on vocal fold mucosa in dogs

A canine model was used to study effects of long-term intubation on vocal fold mucosa. Dogs' larynges were removed 5 weeks after a 7-day intubation period and were compared with control tissue. Intubation effects on vocal fold mucosa were highly variable. Most severe damage was observed posteriorly, at the presumed location of direct tube-mucosa contact. Effects judged to be less severe but still significant were noted in tissue anterior to this site. Morphometric analysis of the layers of the intubated mucosa revealed significant differences in epithelium, connective tissue, and glands, as compared with control tissue. Differences were also observed for blood vessels and nerves. Of particular clinical importance was evidence of damage along membranous, as well as cartilaginous, portions of the true vocal fold, and of damaged connective tissue and cartilage underlying epithelium which appeared normal. Implications of the findings for recovery from intubation, and for voice, are discussed.     

Vocal Fold Paralysis Following Radiotherapy for Nasopharyngeal Carcinoma: Laryngeal Electromyography Findings

Laryngeal electromyography was used to study the pattern of neurological injury in three patients with unilateral vocal fold paralysis following radiotherapy for nasopharyngeal carcinoma. The thyroarytenoid and cricothyroid muscles were assessed to give an indication of recurrent and superior laryngeal nerve function. Two patients demonstrated both recurrent and superior laryngeal neuropathy suggesting injury at the skull base. The other patient had only recurrent laryngeal neuropathy indicating more distal involvement. Subclinical neuropathic changes were seen in two cases on the side contralateral to the vocal fold paralysis. These patients may be at increased risk of developing bilateral vocal fold paralysis and potentially life-threatening airway obstruction. Long-term follow-up is recommended for such patients, especially if medialization thyroplasty is being considered. This is the first report describing the use of electromyography to determine the pattern of nerve injury in patients with vocal fold paralysis following head and neck radiotherapy.     

Laryngeal injuries after short-versus long-term intubation

Forty-five patients were seen over a 5-year period with laryngeal injuries following endotracheal intubation (ETI). The mean duration of ETI was 5.6 days (2 hours to 37 days). Patients intubated for less than 24 hours were most likely to present with a vocal fold immobility or an anterior glottic web. Long-term intubation was associated with the development of subglottic stenoses and granulomas. Patients with vocal fold immobility were seen more often after ETI for surgical reasons and had a significantly higher incidence of previous intubation and tobacco usage. Subglottic stenoses were seen in younger patients intubated for medical reasons and associated with nasogastric tubes and longer periods of intubation.