Causes of poor performance of horses during training, racing, or showing: 348 cases (1992-1996)

OBJECTIVE

To determine results for horses undergoing a high-speed treadmill examination, including videoendoscopy of the pharynx and larynx before and during exercise, echocardiography before and after exercise, and electrocardiography before, during, and after exercise, because of poor performance.

DESIGN

Retrospective study.

ANIMALS

348 horses.

RESULTS

A definitive diagnosis was obtained for 256 (73.5%) horses. One hundred forty-eight horses had dynamic obstruction of the airway during exercise, 33 had clinically important cardiac arrhythmias alone, 22 had a combination of dynamic airway obstruction and clinically important cardiac arrhythmias, 19 had poor cardiac fractional shortening immediately after exercise, 10 had exertional rhabdomyolyis, 15 had clinically apparent lameness, and 9 had other disorders. Thirty-nine of the horses with dynamic obstruction of the airway during exercise had multiple airway abnormalities. Fifty-three horses also had subclinical myopathy

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggest that a complete evaluation, including a high-speed treadmill examination, should be conducted in horses with poor performance, regardless or whether horses do or do not have a history of abnormal respiratory noises and particularly if the horses have grade-II or -III left laryngeal hemiplegia.

Arytenoid cartilage dislocation: a 20-year experience

SUMMARY

Arytenoid cartilage dislocation is an infrequently diagnosed cause of vocal fold immobility. Seventy-four cases have been reported in the literature to date. Intubation is the most common origin, followed by external laryngeal trauma. Decreased volume and breathiness are the most common presenting symptoms. We report on 63 patients with arytenoid cartilage dislocation treated by the senior author (RTS) since 1983. Significantly more posterior than anterior dislocations were represented. Although reestablishing joint mobility is difficult, endoscopic reduction should be considered to align the heights of the vocal processes. This process may result in significant voice improvement even long after the dislocation. Strobovideolaryngoscopy, laryngeal electromyography, and laryngeal computed tomography (CT) imaging are helpful in the evaluation of patients with vocal fold immobility to help distinguish arytenoid cartilage dislocation from vocal fold paralysis. Familiarity with signs and symptoms of arytenoid cartilage dislocation and current treatment techniques improves the chances for optimal therapeutic results.

Orotracheal intubation through the laryngeal mask airway in paediatric patients with Treacher-Collins syndrome

The laryngeal mask airway (LMA) is useful as an airway intubator (conduit) for an intubating tracheal bougie or fibreoptic bronchoscope, over which a tracheal tube is passed. However, in our paediatric patients with Treacher-Collins syndrome, only the latter technique was successful. This was attributed to the fact that a posteriorly protruded tongue displaced the LMA, made the glottis move considerably anterior and interfered with the attempts to enter the trachea with a bougie. Downward displacement of the epiglottis, which can sometimes impair the intubation technique through the LMA, was not observed in our patients. Partial obstruction of a tracheal tube within the LMA occurred in one of the patients.

Laryngeal carcinoma: sclerotic appearance of the cricoid and arytenoid cartilage--CT-pathologic correlation

PURPOSE

To assess the significance of sclerotic-appearing cricoid and arytenoid cartilage with computed tomography (CT) in patients with laryngeal carcinoma.

MATERIALS AND METHODS

CT scans obtained in 75 patients with laryngeal carcinoma were prospectively studied; laryngeal CT studies obtained in 50 patients without laryngeal carcinoma were retrospectively reviewed.

RESULTS

Twenty-four of the 75 patients (32%) with laryngeal carcinoma had sclerotic cartilage. Evaluation of pathologic specimens obtained in 12 of these 24 patients showed 11 cases of sclerotic arytenoid cartilage and two cases of sclerotic cricoid cartilage. Tumor infiltration was demonstrated in six of these cases but not in the seven others. In 11 of the 12 cases with pathologic proof, however, tumor was adjacent to the perichondrium. In the 12 cases without pathologic proof, the proportion was similar. The positive predictive value of this sign for cartilaginous invasion was 46%.

CONCLUSION

Although it is not a reliable sign of cartilaginous invasion, sclerotic-appearing cricoid and arytenoid cartilage in patients with laryngeal carcinoma is predictive of the tumor to this cartilage.

Upper airway function during maximal exercise in horses with obstructive upper airway lesions. Effect of surgical treatment

Upper airway pressure was measured during maximal exercise in 10 Thoroughbred racehorses with naturally occurring upper airway obstruction. Left laryngeal hemiplegia and arytenoid chondropathy resulted in substantial increases (30-40 cm H2O) in inspiratory upper airway pressure (Pl), whereas complicated aryepiglottic entrapment and subepiglottic cysts produced only modest increases (15 cm H2O) in Pl. Uncomplicated aryepiglottic entrapment and grade IV pharyngeal lymphoid hyperplasia produced only slight increases (3-5 cm H2O). In general, surgical procedures restored airway pressures to within normal limits. Subtotal arytenoidectomy improved but did not normalize airway pressures in horses with arytenoid chondropathy. Pharyngeal lymphoid hyperplasia appeared to have little effect on upper airway function.

Laryngeal involvement in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory disease affecting the synovial membrane, which causes joint damage and bone destruction. Extra-articular manifestations are numerous, involving multiple organ systems. Rheumatoid nodules are common extra-articular findings occurring in 20% RA patients. They develop most commonly in pressure areas (elbows and finger joints) and may occasionally affect internal organs including pleura, lungs, meninges, larynx, and others. Furthermore, RA affects the ear, nose, and throat, causing various otorhinolaryngological symptoms. In this report we describe two patients with RA and laryngeal involvement, mostly rheumatoid nodule formation, with a review of the literature.

New insights into the pathomechanism of postintubation arytenoid subluxation

BACKGROUND

Impaired movement of the cricoarytenoid joint with hoarseness and immobility of the vocal ligament can occur as a consequence of endotracheal intubation. The biomechanics and pathomechanism of cricoarytenoid subluxation have not been demonstrated to date.

METHODS

The present study attempts to simulate the trauma that has been associated with arytenoid cartilage subluxation in intubation trials on 37 unfixed larynges in cadavers from persons aged 25 to 89 years. Larynges were intubated or extubated according to former conceptions of arytenoid subluxation, which assume that the arytenoid tip enters the lumen of the tracheal tube, or that a deflection of the arytenoid occurs during withdrawal of the endotracheal tube with the cuff of the tube only partially deflated. Also, manual attempts were carried out to subluxate the arytenoid cartilage. Subsequently after dissecting the left and right cricoarytenoid joint from each larynx, the morphologic changes induced experimentally were analyzed using gross microscopic and histologic methods.

RESULTS

Within the scope of the experiment, it proved impossible to produce any subluxation of a cricoarytenoid joint. Histologic analysis revealed injuries of synovial folds, joint-surface impressions of the articular cartilage, and fractures in the area of the subchondral bone in some joints.

CONCLUSIONS

Based on the morphologic results, it was concluded that intubation trauma of the cricoarytenoid joint does not cause subluxation per se, but rather that formation of a hemarthros or fractures of the joint bodies lead to fixation of the joint surfaces in an abnormal position. Subsequent ankylosis may occur.

Cricoarytenoid arthritis: a cause of acute upper airway obstruction in rheumatoid arthritis

PURPOSE

To report acute upper airway obstruction due to cricoarytenoid arthritis, a well known but uncommon complication of rheumatoid arthritis.

CLINICAL FEATURES

We report the case of a 70-yr-old female scheduled for a colostomy who had been suffering from rheumatoid arthritis for 17 years. Preoperative history and physical examination revealed no cardiopulmonary compromise. Anesthesia was induced while an assistant immobilized the cervical spine and an atraumatic intubation was performed. Surgery was uneventful. Muscle paralysis was reversed, demonstrated by normalization of the train-of-four response, and the patient was extubated awake. Shortly postextubation, the patient developed inspiratory stridor, which disappeared after a second dose of neostigmine. The patient was transported to the postanesthesia care unit. Just prior to arrival the patient once again developed inspiratory stridor, became distressed, and oxygen saturation decreased. Direct laryngoscopy followed by a nasal fibreoptic examination of the larynx was performed. Cricoarytenoid arthritis secondary to rheumatoid arthritis with airway compromise was diagnosed. An uneventful awake tracheostomy was performed. The patient was discharged on day ten with a colostomy and a tracheostomy in place. One month postdischarge the patient's trachea was decannulated. On follow-up, a normal voice and mobile cords were observed.

CONCLUSION

Cricoarytenoid arthritis is an infrequent complication of rheumatoid arthritis. A thorough history and physical examination are necessary to recognize signs and symptoms of cricoarytenoid arthritis. Prompt recognition of airway obstruction due to cricoarytenoid arthritis is essential for appropriate management.

Laryngeal anatomic differences in pediatric patients with severe laryngomalacia

OBJECTIVES

To compare the aryepiglottic (AE) length in pediatric patients who have severe laryngomalacia (SL) and are undergoing aryepiglottoplasty with the AE length of a convenience sample of control patients without laryngomalacia.

DESIGN

Prospective case-control study.

SETTING

A tertiary-care pediatric hospital.

RESULTS

The mean AE fold length-glottic length ratio for patients with SL (0.380) was significantly lower than the mean ratio for controls (0.535) (P = .004 in 2-sample t test with unequal variance). For patients with SL, the aryepiglottoplasy procedure resulted in an average AE length increase-glottic length ratio of 0.330. Seven of the patients with SL were also diagnosed as having an underlying neurologic condition, and 18 had a diagnosis of gastroesophageal reflux disease. Two patients with SL required a tracheotomy for treatment of persistent airway obstruction.

CONCLUSIONS

In this series, patients with SL had lower AE fold length-glottic length ratios and more frequent occurrence of neuromuscular tone abnormalities (especially gastroesophageal reflux) than controls. These 2 findings may be related in that low intrauterine tone might contribute to anatomic underdevelopment.

Congenital laryngeal stridor secondary to flaccid epiglottis, anomalous accessory cartilages and redundant aryepiglottic folds

Most laryngeal anomalies are supraglottic and laryngomalacia is the most common. Cysts, bifid epiglottis and absence of the epiglottis are uncommon. An 18-year-old Caucasian man had long-standing stridor caused by anomalous supraglottic structures: a small floppy epiglottis, enlarged accessory cartilages and redundant aryepiglottic folds. These structures were excised and the airway was improved. The ventral portions of the fourth arches become the aryepiglottic folds and lateral segments of the epiglottis. A disturbance in this portion of the fourth arch may explain the anomaly. The cartilaginous contributions to the epiglottis were possibly isolated as accessory cartilages. Epiglottic anomalies may be associated with other anomalies, especially the digits of the hand. This patient had a short lingual frenulum and mild macroglossia.

Arytenoid appearance and vertical level difference between the paralyzed and innervated vocal cords

OBJECTIVES/HYPOTHESIS

In unilateral vocal fold paralysis, it has been generally accepted that the paralyzed vocal fold presents at a higher level than a normally innervated vocal fold. In this study, we correlate the appearances of the paralyzed arytenoid and the differences in level between the paralyzed and innervated vocal folds.

STUDY DESIGN

Retrospective review using video-recorded images of larynx.

METHODS

A total of 38 patients were selected for this study who reported symptoms of voice change attributable to a paralyzed vocal fold unilaterally. Video recordings were obtained using the laryngeal telescope. The heights were assessed according to the paralyzed positions, status (inspiration or phonation), and appearances of the paralyzed arytenoid. The appearances of paralyzed arytenoid were further clarified as the portions of the medial surface of the arytenoid that were visualized.

RESULTS

In medial paralysis, the paralyzed vocal fold appeared mainly as being at an equal vertical level or as having no distinct difference from normal vocal fold during phonation. However, a few cases of medial paralysis showed a lower than normal or higher than normal vocal fold during phonation, depending on the appearance of the paralyzed arytenoid. In lateral paralysis, most of the paralyzed vocal folds were not higher than the innervated vocal folds during phonation.

CONCLUSIONS

The heights of paralyzed vocal folds were variable depending on the paralyzed positions, the status of the larynx, and appearances of the paralyzed arytenoid. The fact that the paralyzed vocal fold is at a higher level than the normal vocal fold should be reconsidered.

Histopathologic changes in the aging human cricoarytenoid joint

Detrimental effects of the natural aging process on the human cricoarytenoid joint have been hypothesized as a possible etiology for the voice changes seen in the aging population. Cellular events occurring at the histologic level, such as cricoarytenoid joint erosion or arthritis may lead to alterations in laryngeal structure which ultimately affect its function and performance. Seven normal human larynges of varying ages ranging from 29 to 69 years of age were examined histopathologically for changes in the cricoarytenoid joint. The synovium, joint space, periarticular muscle, and respiratory epithelium were evaluated for the presence of inflammatory changes or edema and degree of vascularity. The location and amount of ossification, elastin, and collagen formation were also noted. There were no appreciable changes noted in the synovium or joint space itself with increasing age. No differences were observed in the degree of elastin or collagen formation. However, there was progressive cricoid and arytenoid ossification and periarticular muscular atrophy and fibrosis. These findings suggest that other laryngeal changes may play a greater role in determining senescent vocal quality rather than changes within the cricoarytenoid joint itself.

Effects of suture tension and surgical approach during unilateral arytenoid lateralization on the rima glottidis in the canine larynx

OBJECTIVES

To evaluate the effect of abduction suture tension and cricothyroid (CT) joint disarticulation on the area, height, and width of the rima glottidis (RG) during unilateral arytenoid lateralization.

STUDY DESIGN

Experimental study.

ANIMALS

Nine canine cadaver larynges.

METHODS

Left arytenoid lateralization was performed with high or low abduction suture tension. RG area, height, and width were measured by computerized planimetric analysis with the epiglottis in an open and closed position. The experiment was performed with the CT joint intact and disarticulated. The effects of suture tension, CT disarticulation, and their interaction on RG area with the epiglottis closed or open were evaluated by repeated measures analysis of variance (ANOVA).

RESULTS

RG area increased by 82% and 129% (P <.0001) with low and high suture tension, respectively. The aperture not covered by the epiglottis in a closed position was 467% larger with high suture tension than with low tension (P <.0001). CT disarticulation had no significant effect on RG geometry with either low or high suture tension (P =.4970).

CONCLUSIONS

Low suture tension increased RG area when the epiglottis was in an open position without increasing RG aperture when the epiglottis was closed. Suture tension had a significant effect on RG opening when the epiglottis was closed. CT disarticulation did not modify the geometry of the RG.

CLINICAL RELEVANCE

Use of a low-suture tension should be considered during arytenoid lateralization because it has the potential to reduce the risk of aspiration pneumonia.

The effect of two modifications of unilateral arytenoid lateralization on rima glottidis area in dogs

OBJECTIVES

To evaluate the clinical outcome and percentage increase in rima glottidis area achieved using a combined technique of cricoarytenoid and thyroarytenoid cartilage lateralization compared with cricoarytenoid cartilage lateralization alone in live anesthetized dogs clinically affected with bilateral laryngeal paralysis.

STUDY DESIGN

Randomized prospective clinical study.

ANIMALS

Twenty dogs with bilateral laryngeal paralysis. Methods-Bilateral laryngeal paralysis was diagnosed by direct laryngoscopy. Each dog was allocated randomly to 1 of 2 surgical groups: CAL (cricoarytenoid lateralization) and CTAL (cricoarytenoid and thyroarytenoid lateralization). Photographs were taken of each larynx before and after surgery, the images were digitized, and the preoperative and postoperative areas of each rima glottidis were measured. The percentage increase in rima glottidis area produced by each of the arytenoid lateralization procedures was compared. Follow-up was obtained by telephone survey of owners and referring veterinarians.

RESULTS

There was no significant difference in mean (+/- SD) percentage increase in rima glottidis area for the CAL group (241.5 +/- 42.9%) or the CTAL group (236.4 +/- 44.5%). Clinical follow-up (median, 18 months postoperatively) indicated 60% of the dogs were still alive and only 1 dog had died as a result of complications related to surgery.

CONCLUSIONS

CTAL for the treatment of canine laryngeal paralysis does not significantly increase rima glottidis area compared with CAL alone. The mean percentage increase in rima glottidis area obtained with both procedures was comparable to previously reported mean increases with CAL in live anesthetized dogs. Both procedures resulted in good long-term clinical outcome.

CLINICAL RELEVANCE

CTAL is as effective as CAL in providing an increased rima glottidis for the treatment of bilateral laryngeal paralysis in dogs.

Partial thyroarytenoid myectomy: an animal study investigating a proposed new treatment for adductor spasmodic dysphonia

A new surgical procedure with potential application for the treatment of adductor spasmodic dysphonia was performed on ten rabbits to assess surgical effects on laryngeal function. Using an external approach, partial unilateral thyroarytenoid (TA) muscle excision was performed through a thyroplasty cartilage window. The contralateral side was left undisturbed as a control. The animals were studied acutely and at 3 months using videolaryngoscopy. Electrophysiologic measurements were recorded at 3 months. The procedure was well tolerated by all animals, with no postoperative infection or aspiration. At 3 months, spontaneous and evoked (recurrent laryngeal nerve stimulation) TA muscle electromyographic potentials were measurable bilaterally. TA compound muscle action potential amplitudes were reduced on the side of myectomy. The threshold of recurrent laryngeal nerve stimulation needed to produce observable vocal fold adduction was increased on the side operated on. Perioperative and long-term (3 months) videolaryngoscopy demonstrated preservation of laryngeal competence with good true vocal cord adduction. Histologic analysis with whole organ sections showed replacement of excised muscle with loose fibroareolar tissue. No evidence of muscle regeneration was observed. The vocal ligament and vocal fold mucosa were intact and undistorted in all specimens. This procedure is technically simple and appears to effectively result in a functional yet weakened TA muscle. Because myectomy includes motor unit end-plate excision, problems associated with reinnervation may be circumvented. TA myectomy may be applicable in patients with focal laryngeal dystonia to decrease muscle spasm.

Prognostic factors in glottic carcinoma clinical stage I and II treated by surgery or radiotherapy

INTRODUCTION

Decision making regarding selection of treatment for early glottic carcinoma remains controversial. This study was undertaken to assess the impact of such factors as patient age, stage of tumor, site and size of characteristic of the lesion, and other characteristics relative to disease free and overall survival rates.

PATIENTS AND METHODS

The records of 145 consecutive patients with stage I and II glottic carcinomas treated between 1954 and 1990 were reviewed retrospectively. Surgery was performed on 50 patients (34.5%), and irradiation therapy was performed on 95 (65.5%). Cox's regression model was used to estimate the hazard ratios of recurrence and death.

RESULTS

Median follow-up was 69.3 months. Death due to cancer or treatment complications occurred in 29 patients, whereas 25 patients died due to causes not related to cancer. Five-year rates for overall survival and disease-free intervals were 94.6% and 70.8%, respectively. Tumor control was achieved by initial surgery or irradiation in 78% and 69.5%, respectively. T stage and vocal cord mobility in this series were not associated with prognosis. Arytenoid involvement intended to indicate a worse prognosis. Other site involvement such as anterior commissure had no prognostic impact.

DISCUSSION

Although stage I and II glottic cancers represent a heterogenous group, survival rates after surgery or radiotherapy vary relatively little. Death due to occurred in 17.9% of patients included in this series, whereas 17.2% died due to causes not related to cancer. Local recurrence following irradiation (29.5%) occurred more frequently than following surgery (10%). The choice of treatment modality for stage I and II glottic cancer should be justified by patient preference, involvement of anterior commissure, and impairment of vocal cord mobility and should not be a contraindication to radiotherapy.

Unilateral arytenoid lateralisation and extraluminal polypropylene ring prostheses for correction of tracheal collapse in the dog

The surgical repair of tracheal collapse in 25 dogs is described. The initial presenting signs included coughing, dyspnoea, gagging, retching, exercise intolerance, cyanosis and collapse. Diagnosis was based upon the clinical signs, plain radiography and tracheal endoscopy. The collapse was corrected by the application of a number of extraluminal polypropylene prosthetic rings applied to the affected trachea. Additionally, a left arytenoid lateralisation was also performed. The perioperative complication rate was approximately 4 per cent, while the success rate was 75 per cent. The technique reduces the likelihood of catastrophic postoperative complications associated with iatrogenic laryngeal paralysis which is a possible complication of placement of extraluminal tracheal support devices.

Computed tomography vs. histology of laryngeal cancer: their value in predicting laryngeal cartilage invasion

Twenty-seven cancerous larynges were examined preoperatively by computed tomography and postoperatively by transaxial anatomic sections. Data from this correlative study provides a new radiographic classification based upon the relationship of the plane of maximal tumor size to the apex, body, or vocal process of the arytenoid. Unlike those tumors whose maximal size lies at or above the apex of the arytenoid, those below have a very high association with cartilage invasion (8% in former group, 86% in latter group). This is explained by our observation of sites of predilection of tumor invasion of the thyroid, cricoid, and arytenoid cartilages. At these sites collagen fibers have been observed to pass through the perichondrium and attach directly to cartilage. These same fibers may serve as a pathway to direct growth of tumor cells. There was no correlation between six histologic parameters and the presence of cartilage invasion.

Glottic configuration after arytenoid adduction

It has been recently noted that laryngeal paralysis results in a complex alteration of the glottis. The membranous segment of the paralyzed vocal fold is shortened, and, during phonation, patients use hyperfunction to shorten the normal vocal fold to about the same length. Additionally, if the paralyzed vocal fold is not near the midline, the angle between the membranous and cartilaginous segments of the vocal fold is decreased, resulting in a "posterior" gap which cannot be closed by hyperadduction of the normal side. To determine whether arytenoid adduction addresses these problems, videolaryngoscopy was analyzed in 11 patients before and after surgery, and results were compared to patient satisfaction and acoustic and aerodynamic assessment. The posterior gap and glottic competence were improved in all patients, but only 6 had improvement in symptoms. Two had persistent vocal fold bowing but achieved good function after Teflon injection. Three patients, all with paralysis for more than 20 years, had no increase in vocal fold length and very little subjective vocal improvement. Arytenoid adduction is most effective in acute cases. Poor functional results in chronic paralysis are related to failure to achieve vocal fold lengthening, presumably due to soft-tissue contracture.

Contact granulomas of the larynx

Ten cases of intubation granulomas and eight cases of contact granulomas not related to intubation were reviewed for the purpose of clinical analysis and pathological investigation. Granulomas were located primarily at the vocal process of the arytenoid cartilage. Additionally, 58 hemilarynges obtained from 37 cadavers with intubation granulomas were evaluated grossly and histopathologically. The intubation granulomas had no side predilections. All eight contact granulomas occurred in males and had a higher incidence of recurrence (three of eight cases) despite complete removal with laser surgery. In an attempt to explain recurrences of these contact granulomas, all three cases were studied clinically and pathologically. Results indicated that they recurred in singers and vocal abusers, and presumably resulted from the continued hammering of one vocal process against the other. Analysis also demonstrated that vocal rehabilitation was essential prior to or immediately after removal of the granuloma to prevent its recurrence. Pathological evaluation of the contact granulomas revealed focal ulceration and a covering of necrotic tissue with desquamating epithelium. The propria mucosa was edematous and infiltrated by chronic inflammatory cells and neutrophils forming focal granulation tissue in a stroma containing proliferated capillaries. Pathological features around local ulcerations were typical of a secondary granuloma while underlying arytenoid cartilage was partially necrotic.

Vocal fold fixation in laryngeal carcinomas

The mechanisms of vocal fold fixation were determined by means of a whole-organ serial section study. A total of 80 laryngectomy specimens, 36 supraglottic and 44 glottic carcinomas, was investigated. In the supraglottic carcinomas, the most frequent cause of fixation of the ipsilateral vocal fold was a deep massive tumor invasion in the arytenoid eminence and the second most frequent cause was an extensive involvement of the thyroarytenoid (TA) muscle. Fixation of the contralateral vocal fold resulted from a deep tumor invasion in the contralateral arytenoid eminence. In the glottic carcinomas, fixation of the ipsilateral vocal fold resulted from an extensive invasion into the TA muscle. Fixation of the contralateral vocal fold was caused chiefly by an invasion into the contralateral TA muscle through the anterior commissure region. It resulted occasionally from an invasion into the interarytenoid muscle and contralateral arytenoid cartilage and cricoarytenoid joint via the posterior part of the larynx.

Degenerative changes in the human cricoarytenoid joint

OBJECTIVE

Changes in the human voice occur during the natural aging process. Occurrence of compromising alterations in the cricoarytenoid joint has been hypothesized as a possible reason for voice changes seen in advanced age and has been discussed controversially until today.

METHODS

The present study analyzes degenerative changes in 42 cricoarytenoid joints from 21 body donors (13 men and 8 women; age range, 42-98 years) by means of histological, immunohistochemical, and scanning electron microscopic methods.

RESULTS

Many patients older than 40 years show distinctly altered joint surfaces at varying levels of intensity. The articular cartilage surface is fibrillated in some places. Chondrocytes near the joint surface appear as voluminous chondrocyte clusters. The superficial cartilage layer shows a positive reaction to type III and type I collagen antibodies.

CONCLUSIONS

Chondrocyte proliferation next to the joint surface, changed collagen synthesis, and fibrillation of the joint surface indicate degenerative alterations. Such changes are well known in cases of limb diarthroses. The changes may impair gross positional or postural movements of the arytenoid cartilages and reduce the degree and extent of vocal ligament closure. The structural changes may also lead to negative functional consequences during vocal production, such as impaired vocal quality and reduced vocal intensity due to air leakage through incompletely or loosely approximated vocal ligaments.

Arytenoid dislocation after cardiac surgery

Occurring most usually as complications of upper aerodigestive tract instrumentation during endotracheal intubation or extubation, arytenoid cartilage dislocation and arytenoid subluxation are uncommon laryngeal injuries. Their precise cause, however, is usually difficult to determine. We encountered arytenoid dislocation following cardiac surgery requiring the use of transesophageal echocardiography (TEE). This case prompted us to review some of the mechanisms of injury to the cricoarytenoid joint. We conclude that even very subtle force may dislocate the arytenoid cartilage. We speculate that careless insertion of a TEE probe is mechanically capable of causing arytenoid dislocation and arytenoid subluxation. As ideal tools for intra-operative cardiovascular monitoring, TEE probes are increasingly being used routinely during cardiovascular surgery. So far, arytenoid cartilage dislocation and subluxation following TEE probe insertion have been reported rarely, but complications caused by TEE may increase in the near future. We wish to emphasize the pathophysiological risks of TEE monitoring and other procedures associated with anesthesia, and the need for a proper explanation to achieve informed consent before carrying out TEE monitoring during cardiac surgeries.

Chondrosarcoma of the larynx: challenges in diagnosis and management

Chondrosarcoma is a rare neoplasm of the larynx with approximately 200 cases reported in the literature. The infrequent occurrence of this neoplasm, and its indolent pattern of growth, can result in a delayed or missed diagnosis, thereby jeopardizing the preservation of laryngeal function. Four cases of chondrosarcoma of the larynx are presented demonstrating the challenges in the diagnosis and management of this neoplasm. Conservation surgery remains the mainstay of therapy aiming towards preservation of the framework and function of the larynx. Two innovative reconstructive techniques are presented which made conservation laryngeal surgery possible in two of the four patients. Indeed, surgical resection with sound oncologic principles must be applied and total laryngectomy may be necessary. On rare occasion radiotherapy may be used, although its value remains controversial.