Arytenoid Cartilage (arytenoid + cartilage)

Distribution by Scientific Domains


Selected Abstracts


Morphology and histology of the larynx of the common toad Rhinella arenarum (Hensel, 1867) (Anura, Bufonidae)

ACTA ZOOLOGICA, Issue 4 2009
Gladys N. Hermida
Abstract The structure of the larynx of the toad Rhinella arenarum was exhaustively studied. The laryngeal skeleton consists of three bilaterally symmetrical cartilages: the cricoid and two arytenoids. Internally, each half-larynx has an anterior and a posterior chamber. The first chamber is delimited by the epithelium covering the arytenoid cartilage and the anterior membrane. The latter consists of fibro-elastic tissue and contains blood capillaries that, judging by their location and distribution, might serve to maintain vocal cord turgidity. At the level of the cricoid cartilage, two structures are reported here for the first time: the posterodorsal and the anteroventral processes. Both processes are associated with the insertion of the posterior membrane. A cartilaginous rod is located at the free margin of the posterior membrane. This rod appears to support the membrane when the air flows. The distal portion of the larynx communicates with the proximal region of the lung. The epithelium of the laryngeal mucosa contains ciliated cells, goblet cells, secretory cells with short microvilli and neuroendocrine cells immunopositive to PGP 9.5. The results obtained in this study provide new information about the internal organization of the larynx in anurans, which could serve as additional morphological characters for phylogenetic relationships. [source]


Study of laryngopharyngeal pathology in Thoroughbred horses in southern California

EQUINE VETERINARY JOURNAL, Issue 9 2009
S. DIAB
Summary Reasons for performing study: There is increasing anecdotal evidence among horse owners, trainers and equine clinicians of a high prevalence of subepiglottic ulcers, suggested to have a negative effect on racing performance. Objectives: To provide a prevalence study and pathological characterisation of laryngopharyngeal lesions with emphasis in the subepiglottic area and, in particular, subepiglottic ulcers. Methods: The study was carried out on 91 Thoroughbred racehorses received for post mortem examination from 4 major Southern California racetracks. The most common reason for submission was catastrophic musculoskeletal injury, but others include sudden death, laminitis, colic, colitis, neurological disorders, pleuropneumonia and arytenoid chondropathy. Laryngopharyngeal specimens were collected and examined grossly; selected cases were also examined histopathologically. Results: Thirteen horses (14.3%) had at least one type of laryngopharyngeal abnormality, 7 horses (7.7%) had lesions in the subepiglottic soft tissues, including 4 subepiglottic ulcers, 2 soft palate ,kissing lesions' and one 'subepiglottic scar'. Eight horses (8.8%) had lesions elsewhere in the laryngopharynx, including mucosal ulcerations, arytenoid chondropathy, epiglottic entrapment and partial absence of arytenoid cartilage. Conclusions and potential relevance: Lesions in the subepiglottic area were among the most prevalent in this study, suggesting that an important percentage of laryngopharyngeal abnormalities may be missed during routine endoscopy of the standing horse, which often does not include the examination of subepiglottic tissues. Pathologically, subepiglottic ulcers were chronic-active with viable hyperplastic epithelial margins, suggesting that proper healing and re-epithelialisation should occur with appropriate treatment. In most cases, the lesions observed do not necessarily indicate a clinical problem and more extensive prevalence studies and correlation between abnormalities found and performance are needed to assess the clinical relevance of subepiglottic soft tissue lesions accurately. [source]


Effect of magnitude and direction of force on laryngeal abduction: Implications for the nerve-muscle pedicle graft technique

EQUINE VETERINARY JOURNAL, Issue 4 2009
P. CRAMP
Summary Reasons for performing study: The nerve-muscle pedicle graft technique is a treatment for recurrent laryngeal neuropathy (RLN), but the optimal placement of the pedicles within the cricoarytenoideus dorsalis (CAD) muscle is unknown. Hypothesis: The magnitude and direction of force placed on the muscular process of the left arytenoid cartilage affects the magnitude of laryngeal abduction. Methods: Five larynges were harvested from cadavers. Using increments of 0.98 N, a dead-weight force generator applied a force of 0,14.7 N for 1 min each to the left muscular process at 0, 10, 20, 30, 40, 50, 60 and 70 angles. The rima glottis was photographed digitally 1 min after each force had been applied. Distances between biomarkers (Lines 1,4) and right to left angle quotient (RLQ) were used to assess the degree of left arytenoid abduction. Results: Increasing force from 0,14.7 N progressively and significantly increased the length of all lines and RLQ, indicating abduction. Furthermore, there was a significant interaction between force and angles. Applying forces of 7.84 N or greater (Lines 2,4 and RLQ) or 11.76 N or greater (Line 1) at angles 0, 10, 20 and 30 resulted in significantly greater abduction than applying the same forces at 40, 50, 60 and 70. Angles of 0,30 correspond with the direction of pull exerted by the lateral compartment of the CAD muscle. Conclusion: In RLN, nerve-muscle pedicle grafts should be placed preferentially in the lateral rather than in the medial compartment of the CAD muscle. Potential relevance: The information presented can be used to assist surgeons in the planning and application of the nerve-muscle pedicle graft procedure. [source]


Implications of different degrees of arytenoid cartilage abduction on equine upper airway characteristics

EQUINE VETERINARY JOURNAL, Issue 7 2008
V. RAKESH
Summary Reason for performing study: The necessary degree of arytenoid cartilage abduction (ACA) to restore airway patency at maximal exercise has not been determined. Objectives: Use computational fluid dynamics modelling to measure the effects of different degrees of ACA on upper airway characteristics of horses during exercise. Hypothesis: Maximal ACA by laryngoplasty is necessary to restore normal peak airflow and pressure in Thoroughbred racehorses with laryngeal hemiplegia. Methods: The upper airway was modeled with the left arytenoid in 3 different positions: maximal abduction; 88% cross-sectional area of the rima glottis; and 75% cross-sectional area of the rima glottis. The right arytenoid cartilage was maximally abducted. Two models were assumed: Model 1: no compensation of airway pressures; and Model 2: airway pressure compensation occurs to maintain peak airflow. The cross-sectional pressure and velocity distributions for turbulent flow were studied at peak flow and at different positions along the airway. Results: Model 1: In the absence of a change in driving pressure, 12 and 25% reductions in cross-sectional area of the larynx resulted in 4.11 and 5.65% reductions in peak airflow and 3.68 and 5.64% in tidal volume, respectively, with mild changes in wall pressure. Model 2: To maintain peak flow, a 6.27% increase in driving tracheal pressure was required to compensate for a cross-sectional reduction of 12% and a 13.63% increase in driving tracheal pressure was needed for a cross-sectional area reduction of 25%. This increase in negative driving pressure resulted in regions with low intraluminal and wall pressures, depending on the degree of airway diameter reduction. Conclusion: Assuming no increase in driving pressure, the decrease in left ACA reduced airflow and tidal volume. With increasing driving pressure, a decrease in left ACA changed the wall pressure profile, subjecting the submaximally abducted arytenoid cartilage and adjacent areas to airway collapse. Clinical relevance: The surgical target of ACA resulting in 88% of maximal cross-sectional area seems to be appropriate. [source]


Development of equine upper airway fluid mechanics model for Thoroughbred racehorses

EQUINE VETERINARY JOURNAL, Issue 3 2008
V. RAKESH
Summary Reason for performing study: Computational fluid dynamics (CFD) models provide the means to evaluate airflow in the upper airways without requiring in vivo experiments. Hypothesis: The physiological conditions of a Thoroughbred racehorse's upper airway during exercise could be simulated. Methods: Computed tomography scanned images of a 3-year-old intact male Thoroughbred racehorse cadaver were used to simulate in vivo geometry. Airway pressure traces from a live Thoroughbred horse, during exercise was used to set the boundary condition. Fluid-flow equations were solved for turbulent flow in the airway during inspiratory and expiratory phases. The wall pressure turbulent kinetic energy and velocity distributions were studied at different cross-sections along the airway. This provided insight into the general flow pattern and helped identify regions susceptible to dynamic collapse. Results: The airflow velocity and static tracheal pressure were comparable to data of horses exercising on a high-speed treadmill reported in recent literature. The cross-sectional area of the fully dilated rima glottidis was 7% greater than the trachea. During inspiration, the area of highest turbulence (i.e. kinetic energy) was in the larynx, the rostral aspect of the nasopharynx was subjected to the most negative wall pressure and the highest airflow velocity is more caudal on the ventral aspect of the nasopharynx (i.e. the soft palate). During exhalation, the area of highest turbulence was in the rostral and mid-nasopharynx, the maximum positive pressure was observed at the caudal aspect of the soft palate and the highest airflow velocity at the front of the nasopharynx. Conclusions and clinical relevance: In the equine upper airway collapsible area, the floor of the rostral aspect of the nasopharynx is subjected to the most significant collapsing pressure with high average turbulent kinetic during inhalation, which may lead to palatal instability and explain the high prevalence of dorsal displacement of the soft palate (DDSP) in racehorses. Maximal abduction of the arytenoid cartilage may not be needed for optimal performance, since the trachea cross-sectional area is 7% smaller than the rima glottidis. [source]


Sedation with detomidine and acepromazine influences the endoscopic evaluation of laryngeal function in horses

EQUINE VETERINARY JOURNAL, Issue 6 2007
C. Lindegaard
Summary Reasons for performing study: Endoscopy of the upper airways of horses is used as a diagnostic tool and at purchase examinations. On some occasions it is necessary to use sedation during the procedure and it is often speculated that the result of the examination might be influenced due to the muscle-relaxing properties of the most commonly used sedatives. Objectives: To evaluate the effect of detomidine (0.01 mg/kg bwt) and acepromazine (0.05 mg/kg bwt) on the appearance of symmetry of rima glottidis, ability to abduct maximally the arytenoid cartilages and the effect on recurrent laryngeal neuropathy (RLN) grade. Methods: Forty-two apparently normal horses underwent endoscopic examination of the upper airways on 3 different occasions, under the influence of 3 different treatments: no sedation (control), sedation with detomidine and sedation with acepromazine. All examinations were performed with a minimum of one week apart. The study was performed as an observer-blind cross-over study. Results: Sedation with detomidine had a significant effect on the RLN grading (OR = 2.91) and ability maximally to abduct the left arytenoid cartilages (OR = 2.91). Sedation with acepromazine resulted in OR = 2.43 for the RLN grading and OR = 2.22 for the ability to abduct maximally. The ability to abduct maximally the right arytenoid cartilage was not altered. Conclusions: Sedating apparently healthy horses with detomidine or acepromazine significantly impairs these horses' ability to abduct fully the left but not the right arytenoid cartilage. This resulted in different diagnosis with respect to RLN when comparing sedation to no sedation. Potential relevance: Since the ability to abduct the right arytenoid cartilage fully is not altered by sedation, it is speculated that horses changing from normal to abnormal laryngeal function when sedated, might be horses in an early stage of the disease. To confirm or reject these speculations, further studies are needed. Until then sedation during endoscopy should be used with care. [source]


Prenatal and early postnatal morphogenesis and growth of human laryngotracheal structures

JOURNAL OF ANATOMY, Issue 2 2008
Pierre Fayoux
Abstract Advances in neonatal medicine have resulted in increased care of fetal and neonatal airways. These advances have required an exhaustive knowledge of fetal airway anatomy and development. The aim of this study was to determine the anatomical development of laryngotracheal structures during the fetal and immediate postnatal period and to correlate these observations with other fetal biometric parameters to estimate developmental particularities of the fetal airway. An anatomical prospective study was based on examination of larynx and trachea from 300 routine autopsies of fetuses and infants, free of malformation and never intubated. Anatomical measurements of cricoid cartilage, thyroid cartilage, glottis, arytenoid cartilage and trachea were performed using a precision calliper and precision divider. Statistical analysis was performed to represent the growth of anatomical structures and to evaluate the correlation with biometric data. Raw data and 10th and 90th percentile curves were fitted satisfactorily with a linear model for gestational age. A linear relationship between laryngotracheal measurement and body weight and height was observed except for glottis length, interarytenoid distance and anterior cricoid height. The diameter of the cricoid lumen was significantly less than that of the trachea and glottis lumen. A sexual dysmorphism was noted for thyroid cartilage measurements and interarytenoid distance, with measurements significantly smaller in females. This study reports the anatomical development of normal laryngotracheal structures during the fetal period. Despite the fact that this study was performed during postmortem examination, these observations can be useful to develop criteria, materials and surgical procedures adapted to fetal and neonatal airways as well as for the purposes of early diagnosis and management of laryngotracheal malformations. [source]


Tremulous arytenoid movements predict severity of glottic stenosis in multiple system atrophy,

MOVEMENT DISORDERS, Issue 10 2010
Tetsutaro Ozawa MD
Abstract To determine whether tremulous arytenoid movements predict the severity of glottic stenosis in patients with multiple system atrophy (MSA), 28 MSA patients and 14 age-matched controls underwent fiberoptic laryngoscopy with video monitoring during wakefulness and under anesthesia induced by intravenous injection of propofol. Presence or absence of tremulous arytenoid movements was recorded during wakefulness. The ratio of glottic stenosis (%), which represents the extent of airway narrowing under anesthesia, was obtained by measuring the inspiratory glottic angle during wakefulness and under anesthesia. The median ratio of glottic stenosis was significantly higher in patients with MSA (57.5%) than in control subjects (0.5%). Tremulous arytenoid movements were characterized by shaking movements of the arytenoid region including the vocal folds, which are most apparent in the arytenoid cartilage. In this study, tremulous arytenoid movements were observed in 18 (64.2%) of 28 patients with MSA, who displayed a significantly higher median ratio of glottic stenosis (71.2%) than other patients (34.9%). None of the control subjects exhibited tremulous arytenoid movements. A clear correlation existed between the ratio of glottic stenosis and disease duration. Our observations indicate that tremulous arytenoid movements are a marker of the severity of glottic stenosis, which confers an increased risk of upper airway obstruction in patients with MSA. 2010 Movement Disorder Society [source]


Supracricoid Laryngectomy Outcomes: The Johns Hopkins Experience

THE LARYNGOSCOPE, Issue 1 2007
Tarik Y. Farrag MD
Abstract Objective: To report the oncologic and functional results from our experience in performing supracricoid laryngectomy (SCL) for selected patients with laryngeal cancer. Study Design: Retrospective chart review. Methods: Twenty-four consecutive patients who underwent SCL for laryngeal cancer in our institution from December 2000 to March 2006 have been reviewed. Reports of the site and extent of tumor, type of reconstruction, preoperative or postoperative radiotherapy, and the final histopathologic examination were reviewed. In addition, the reports of the preoperative examination, inpatient course, and postoperative follow-up were reviewed. Results: A total of 24 patients were involved in the study; 19 had tumors involving the glottic region, and 5 patients had tumors involving both the glottic and supraglottic regions (transglottic). Ten patients had their SCL for postradiotherapy recurrence/persistence of disease. Eighteen patients underwent reconstruction through cricohyoidoepiglottopexy (CHEP), whereas six patients had cricohyoidopexy (CHP). Eleven patients had an arytenoid cartilage resected; 8 of 11 had CHEP, and 3 of 11 had CHP. All patients had a tracheostomy and percutaneous endoscopic gastrostomy (PEG) tube placement performed at the same time as the SCL. The median hospital stay period was 6 days. Twenty-three of 24 had successful tracheostomy tube decannulation, with a median time to decannulation of 37 days. The median time to removal of the PEG tube was 70 days. The complications with SCL were postoperative wound infection in two patients (SCL/CHP) and the need for completion total laryngectomy secondary to intractable aspiration in one patient with SCL/CHP. One patient with SCL/CHEP had a ruptured pexy and subsequently underwent a second reconstruction with successful tracheostomy and PEG tube removal. One of 24 patients is still PEG tube dependant, and he had postoperative radiotherapy. Fifteen patients underwent concurrent neck dissection. None of the patients had any local or regional recurrence, with a median follow-up period of 3 years. All final surgical margins were negative for tumor invasion. Three patients had postoperative radiotherapy, two patients because of nodal metastases in the excised lymph nodes and one because of perineural invasion on final histopathologic examination of the SCL specimen. There were no perioperative deaths. Conclusion: SCL with CHEP or CHP represents an effective technique that can be taught and effectively used to avoid a total laryngectomy while maintaining physiologic speech and swallowing in selected patients with advanced stage primary laryngeal cancer or recurrent/persistent laryngeal cancer after radiotherapy. There is a good functional recovery with acceptable morbidity and an excellent oncologic outcome when strict selection criteria are applied and a formal swallowing rehabilitation program is followed. [source]


Long-Term Result of the New Endoscopic Vocal Fold Medialization Surgical Technique for Laryngeal Palsy,

THE LARYNGOSCOPE, Issue 2 2006
Koichiro Nishiyama MD
Abstract Objective: The conventional surgical method for a case of unilateral laryngeal nerve paralysis with large glottal gap requires an external cervical incision. In the present study, we developed an endoscopic technique of vocal fold medialization that can make the external incision unnecessary. This procedure of autologous transplantation of fascia into the vocal fold (ATFV) was developed for the successful treatment of unilateral laryngeal nerve paralysis. However, the method seemed to be effective only for patients with a relatively mild glottal gap. Study Design and Methods: In the present study, we modified the method of medialization using the ATFV technique to obtain effective closure of a large glottal gap. To overcome this difficulty, an attempt was made to extend the site of transplantation more posteriorly so as to adduct the vocal process of the arytenoid cartilage in the body of the vocal fold. Results: This new technique was applied to eight cases of patients with unilateral laryngeal paralysis with severe dysphonia. None of the patients showed any evidence of falling off of the graft. Elongation of the maximum phonation time and a decrease in airflow rate during phonation were obtained with improvement in voice quality in all patients 1 year after the surgery. Conclusions: This method, with its less invasive approach, proved to be useful for the treatment of large glottal gap due to unilateral laryngeal nerve paralysis. [source]


A comparison of a flexometallic tracheal tube with the intubating laryngeal mask tracheal tube for nasotracheal fibreoptic intubation using the two-scope technique,

ANAESTHESIA, Issue 12 2009
M. R. Rai
Summary We compared the incidence and site of impingement of a flexometallic tracheal tube with those of the re-usable intubating laryngeal mask (ILMA) tube in 60 anaesthetised patients undergoing nasotracheal fibreoptic intubation for oral surgery. A two-scope technique was used, observing the site of impingement with one scope whilst intubating with the other. The tubes were 6.0-mm in females and 6.5-mm in males. Impingement occurred with 10 (33%) flexometallic and 2 (7%) ILMA tubes (p < 0.032). In all but one case, the impingement was posterior to the right arytenoid cartilage. When impingement was observed, a single disempaction with a 90 anticlockwise rotational manoeuvre overcame impingement in every case except one, allowing successful intubation. We conclude that the incidence of impingement of the tracheal tube, and therefore of potential laryngeal trauma from nasotracheal fibreoptic intubation, is significantly greater with the flexometallic tube than with the ILMA tube. [source]


Sedation with detomidine and acepromazine influences the endoscopic evaluation of laryngeal function in horses

EQUINE VETERINARY JOURNAL, Issue 6 2007
C. Lindegaard
Summary Reasons for performing study: Endoscopy of the upper airways of horses is used as a diagnostic tool and at purchase examinations. On some occasions it is necessary to use sedation during the procedure and it is often speculated that the result of the examination might be influenced due to the muscle-relaxing properties of the most commonly used sedatives. Objectives: To evaluate the effect of detomidine (0.01 mg/kg bwt) and acepromazine (0.05 mg/kg bwt) on the appearance of symmetry of rima glottidis, ability to abduct maximally the arytenoid cartilages and the effect on recurrent laryngeal neuropathy (RLN) grade. Methods: Forty-two apparently normal horses underwent endoscopic examination of the upper airways on 3 different occasions, under the influence of 3 different treatments: no sedation (control), sedation with detomidine and sedation with acepromazine. All examinations were performed with a minimum of one week apart. The study was performed as an observer-blind cross-over study. Results: Sedation with detomidine had a significant effect on the RLN grading (OR = 2.91) and ability maximally to abduct the left arytenoid cartilages (OR = 2.91). Sedation with acepromazine resulted in OR = 2.43 for the RLN grading and OR = 2.22 for the ability to abduct maximally. The ability to abduct maximally the right arytenoid cartilage was not altered. Conclusions: Sedating apparently healthy horses with detomidine or acepromazine significantly impairs these horses' ability to abduct fully the left but not the right arytenoid cartilage. This resulted in different diagnosis with respect to RLN when comparing sedation to no sedation. Potential relevance: Since the ability to abduct the right arytenoid cartilage fully is not altered by sedation, it is speculated that horses changing from normal to abnormal laryngeal function when sedated, might be horses in an early stage of the disease. To confirm or reject these speculations, further studies are needed. Until then sedation during endoscopy should be used with care. [source]


The historical Latin and etymology of selected anatomical terms of the larynx

CLINICAL ANATOMY, Issue 2 2010
Daniel D. Lydiatt
Abstract The etymological evolution of the anatomical terms larynx, cricoid, glottis, epiglottis, and thyroid (cartilage) dates to antiquity. Human dissection replaced animal in the 16th and 17th centuries and terms evolved. This evolution was recorded in the literature largely in Latin. We translated key studies of laryngeal anatomy from the 16th century to better understand this evolution. We present the Latin with our translations, and historical commentary as essential to this understanding. Vesalius favored the Latin scutiform (shield) for the thyroid cartilage, but recognized peltalis (shield). The Basle Nomina Anatomica (BNA) chose the Greek thyroid (,,,,o,,, ) for modern convention. Vesalius used the name "innominate" for the cricoid cartilage, but described its resemblance to a ring, drawn in the margin of the Fabrica. Krikoid, the Greek for ring shaped, was adopted by the BNA. Although the term arytenoid was used for centuries, Vesalius argued the Greek name referred to the spout of a cup or ladle. He recognized the human arytenoids as two separate cartilages as opposed to single in certain animals. The glottis was defined by Vesalius as the vocal fold or rima glottidis of today, and he advanced its function by understanding the paired, mobile arytenoid cartilages. He defined the function of the epiglottis and first described the pre-epiglottic space. Vesalius' student at Padua, Italy, Columbo contributed to anatomical knowledge, but animosity between them clouded the record. Harvey, working 75 years later in England, offers an evolutionary window from Vesalius. Harvey's laryngeal studies preceded by a decade his groundbreaking studies on the circulation of blood. Clin. Anat. 23:131,144, 2010. 2010 Wiley-Liss, Inc. [source]