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Azure Wilson - One of the best experts on this subject based on the ideXlab platform.
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spatial motion of Arytenoid Cartilage using dynamic computed tomography combined with euler angles
Laryngoscope, 2020Co-Authors: Huijing Bao, Xi Wang, Xi Chen, Zheyi Zhang, Jinan Wang, Peiyun Zhuang, Jack J Jiang, Azure WilsonAbstract:Objective To investigate the feasibility of dynamic computed tomography in recording and describing the spatial motion characteristics of the Arytenoid Cartilage. Methods Dynamic computed tomography recorded the real-time motion trajectory of the Arytenoid Cartilage during inspiration and phonation. A stationary coordinate system was established with the cricoid Cartilage as a reference and a motion coordinate system was established using the movement of the Arytenoid Cartilage. The Euler angles of the Arytenoid Cartilage movement were calculated by transformation of the two coordinate systems, and the spatial motion characteristics of the Arytenoid Cartilage were quantitatively studied. Results Displacement of the cricoid Cartilage was primarily inferior during inspiration. During phonation, the displacement was mainly superior. When the glottis closed, the superior displacement was about 5-8 mm within 0.56 s. During inspiration, the Arytenoid Cartilage was displaced superiorly approximately 1-2 mm each 0.56 s. The rotation angle was subtle with slight rotation around the XYZ axis, with a range of 5-10 degrees. During phonation, the displacement of the Arytenoid Cartilage was mainly inferior (about 4-6 mm), anterior (about 2-4 mm) and medial (about 1-2 mm). The motion of the Arytenoid Cartilage mainly consisted of medial rolling, and there was an alternating movement of anterior-posterior tilting. The Arytenoid Cartilage rolled medially (about 20-40 degrees within 0.56 s), accompanied by anterior-posterior tilting (about 15-20 degrees within 0.56 s). Conclusion Dynamic computed tomography recordings of Arytenoid Cartilage movement can be combined with Euler transformations as a tool to study the spatial characteristics of laryngeal structures during phonation. Level of evidence 4 Laryngoscope, 130:E646-E653, 2020.
Dominic Thyagarajan - One of the best experts on this subject based on the ideXlab platform.
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Arytenoid Cartilage movements are hypokinetic in parkinson s disease a quantitative dynamic computerised tomographic study
PLOS ONE, 2017Co-Authors: Laura Perjudumbrava, Ken Lau, Debbie Phyland, Vicki Papanikolaou, Paul Finlay, Richard Beare, Stephen Stuckey, Philip G Bardin, Peter A Kempster, Dominic ThyagarajanAbstract:BACKGROUND Voice change is one of the earliest features of Parkinson's disease. However, quantitative studies of vocal fold dynamics which are needed to provide insight into disease biology, aid diagnosis, or track progression, are few. METHODS We therefore quantified Arytenoid Cartilage movements and glottic area during repeated phonation in 15 patients with Parkinson's disease (symptom duration < 6 years) and 19 controls, with 320-slice computerised tomography (CT). We related these measures to perceptual voice evaluations and spirometry. We hypothesised that Parkinson's disease patients have a smaller inter-Arytenoid distance, a preserved or larger glottic area because vocal cord bowing has previously been reported, less variability in loudness, more voice dysdiadochokinesis and breathiness and a shortened phonation time because of Arytenoid hypokinesis relative to glottic area. RESULTS Inter-Arytenoid distance in Parkinson's disease patients was moderately smaller (Mdn = 0.106, IQR = 0.091-0.116) than in controls (Mdn = 0.132, IQR = 0.116-0.166) (W = 212, P = 0.015, r = -0.42), normalised for anatomical and other inter-subject variance, analysed with two-tailed Wilcoxon's rank sum test. This finding was confirmed in a linear mixed model analysis-Parkinson's disease significantly predicted a reduction in the dependent variable, inter-Arytenoid distance (b = -0.87, SEb = 0.39, 95% CI [-1.66, -0.08], t(31) = -2.24, P = 0.032). There was no difference in glottic area. On perceptual voice evaluation, patients had more breathiness and dysdiadochokinesis, a shorter maximum phonation time, and less variability in loudness than controls. There was no difference in spirometry after adjustment for smoking history. CONCLUSIONS As predicted, vocal fold adduction movements are reduced in Parkinson's disease on repeated phonation but glottic area is maintained. Some perceptual characteristics of Parkinsonian speech reflect these changes. We are the first to use 320-slice CT to study laryngeal motion. Our findings indicate how Parkinson's disease affects intrinsic laryngeal muscle position and excursion.
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Arytenoid Cartilage feature point detection using laryngeal 3D CT images in Parkinson's disease
2017 39th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2017Co-Authors: Nandakishor Desai, Paari Palaniswami, Dominic Thyagarajan, Marimuthu PalaniswamiAbstract:Parkinson's disease is a neurodegenerative disorder that results in progressive degeneration of nerve cells. It is generally associated with the deficiency of dopamine, a neurotransmitter involved in motor control of humans and thus affects the motor system. This results in abnormal vocal fold movements in majority of the Parkinson's patients. Analysis of vocal fold abnormalities may provide useful information to assess the progress of Parkinson's disease. This is accomplished by measuring the distance between the Arytenoid Cartilages during phonation. In order to automate this process of identifying Arytenoid Cartilages from CT images, in this work, a rule-based approach is proposed to detect the Arytenoid Cartilage feature points on either side of the airway. The proposed technique detects feature points by localizing the anterior commissure and analyzing airway boundary pixels to select the optimal feature point based on detected pixels. The proposed approach achieved 83.33% accuracy in estimating clinically-relevant feature points, making the approach suitable for automated feature point detection. To the best of our knowledge, this is the first such approach to detect Arytenoid Cartilage feature points using laryngeal 3D CT images.
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Arytenoid Cartilage movements are hypokinetic in Parkinson’s disease: A quantitative dynamic computerised tomographic study
2017Co-Authors: Laura Perju-dumbrava, Ken Lau, Debbie Phyland, Vicki Papanikolaou, Paul Finlay, Richard Beare, Philip Bardin, Stephen Stuckey, Peter Kempster, Dominic ThyagarajanAbstract:BackgroundVoice change is one of the earliest features of Parkinson’s disease. However, quantitative studies of vocal fold dynamics which are needed to provide insight into disease biology, aid diagnosis, or track progression, are few.MethodsWe therefore quantified Arytenoid Cartilage movements and glottic area during repeated phonation in 15 patients with Parkinson’s disease (symptom duration < 6 years) and 19 controls, with 320-slice computerised tomography (CT). We related these measures to perceptual voice evaluations and spirometry. We hypothesised that Parkinson’s disease patients have a smaller inter-Arytenoid distance, a preserved or larger glottic area because vocal cord bowing has previously been reported, less variability in loudness, more voice dysdiadochokinesis and breathiness and a shortened phonation time because of Arytenoid hypokinesis relative to glottic area.ResultsInter-Arytenoid distance in Parkinson’s disease patients was moderately smaller (Mdn = 0.106, IQR = 0.091–0.116) than in controls (Mdn = 0.132, IQR = 0.116–0.166) (W = 212, P = 0.015, r = −0.42), normalised for anatomical and other inter-subject variance, analysed with two-tailed Wilcoxon’s rank sum test. This finding was confirmed in a linear mixed model analysis—Parkinson’s disease significantly predicted a reduction in the dependent variable, inter-Arytenoid distance (b = −0.87, SEb = 0.39, 95% CI [−1.66, −0.08], t(31) = −2.24, P = 0.032). There was no difference in glottic area. On perceptual voice evaluation, patients had more breathiness and dysdiadochokinesis, a shorter maximum phonation time, and less variability in loudness than controls. There was no difference in spirometry after adjustment for smoking history.ConclusionsAs predicted, vocal fold adduction movements are reduced in Parkinson’s disease on repeated phonation but glottic area is maintained. Some perceptual characteristics of Parkinsonian speech reflect these changes. We are the first to use 320-slice CT to study laryngeal motion. Our findings indicate how Parkinson’s disease affects intrinsic laryngeal muscle position and excursion.
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Representative glottic areas measured by automated segmentation.
2017Co-Authors: Laura Perju-dumbrava, Ken Lau, Debbie Phyland, Vicki Papanikolaou, Paul Finlay, Richard Beare, Philip Bardin, Stephen Stuckey, Peter Kempster, Dominic ThyagarajanAbstract:Each row shows a measurement taken at a single time point in a different subject. Axial, sagittal and coronal images are shown left to right. Cords apart (A, B, C), Cords towards closure (D, E, F). Hourglass deformity (G, H, I). Annotations: A indicates the Arytenoid Cartilage, and C, the cricoid Cartilage.
Yukio Hayashi - One of the best experts on this subject based on the ideXlab platform.
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cardiovascular operation a significant risk factor of Arytenoid Cartilage dislocation subluxation after anesthesia
Annals of Cardiac Anaesthesia, 2017Co-Authors: Seri Tsuru, Mayuko Wakimoto, Takeshi Iritakenishi, Makoto Ogawa, Yukio HayashiAbstract:Background: Arytenoid Cartilage dislocation/subluxation is one of the rare complications following tracheal intubation, and there have been no reports about risk factors leading this complication. From our clinical experience, we have an impression that patients undergoing cardiovascular operations tend to be associated with this complication. Aims: We designed a large retrospective study to reveal the incidence and risk factors predicting the occurrence and to examine whether our impression is true. Settings and Designs: This was a retrospective study. Methods: We retrospectively studied 19,437 adult patients who were intubated by an anesthesiologist in our operation theater from 2002 to 2008. The tracheal intubation was performed by a resident anesthesiologist managing the patients. Only patients whose postoperative voice was disturbed more than 7 days were referred to the Department of Otorhinolaryngology-Head and Neck Surgery and examined using laryngostroboscopy by a laryngologist to diagnose Arytenoid Cartilage dislocation/subluxation. We evaluated age, sex, weight, height, duration of intubation, difficult intubation, and major cardiovascular operation as risk factors to lead this complication. Statistical Analysis: The data were analyzed by logistic regression analysis to assess factors for Arytenoid Cartilage dislocation/subluxation after univariate analyses using logistic regression analysis. Results: Our analysis indicated that difficult intubation (odds ratio: 12.1, P = 0.018) and cardiovascular operation (odds ratio: 9.9, P < 0.001) were significant risk factors of Arytenoid Cartilage dislocation/subluxation. Conclusion: The present study demonstrated that major cardiovascular operation is one of the significant risk factors leading this complication.
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Cardiovascular operation: A significant risk factor of Arytenoid Cartilage dislocation/subluxation after anesthesia
Wolters Kluwer Medknow Publications, 2017Co-Authors: Seri Tsuru, Mayuko Wakimoto, Takeshi Iritakenishi, Makoto Ogawa, Yukio HayashiAbstract:Background: Arytenoid Cartilage dislocation/subluxation is one of the rare complications following tracheal intubation, and there have been no reports about risk factors leading this complication. From our clinical experience, we have an impression that patients undergoing cardiovascular operations tend to be associated with this complication. Aims: We designed a large retrospective study to reveal the incidence and risk factors predicting the occurrence and to examine whether our impression is true. Settings and Designs: This was a retrospective study. Methods: We retrospectively studied 19,437 adult patients who were intubated by an anesthesiologist in our operation theater from 2002 to 2008. The tracheal intubation was performed by a resident anesthesiologist managing the patients. Only patients whose postoperative voice was disturbed more than 7 days were referred to the Department of Otorhinolaryngology-Head and Neck Surgery and examined using laryngostroboscopy by a laryngologist to diagnose Arytenoid Cartilage dislocation/subluxation. We evaluated age, sex, weight, height, duration of intubation, difficult intubation, and major cardiovascular operation as risk factors to lead this complication. Statistical Analysis: The data were analyzed by logistic regression analysis to assess factors for Arytenoid Cartilage dislocation/subluxation after univariate analyses using logistic regression analysis. Results: Our analysis indicated that difficult intubation (odds ratio: 12.1, P = 0.018) and cardiovascular operation (odds ratio: 9.9, P < 0.001) were significant risk factors of Arytenoid Cartilage dislocation/subluxation. Conclusion: The present study demonstrated that major cardiovascular operation is one of the significant risk factors leading this complication
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prolonged hoarseness and Arytenoid Cartilage dislocation after tracheal intubation
BJA: British Journal of Anaesthesia, 2009Co-Authors: H Yamanaka, Yukio Hayashi, Y Watanabe, H Uematu, Takashi MashimoAbstract:Background Hoarseness is a common complication after tracheal intubation and prolonged hoarseness may be very limiting for a patient. This study was designed to examine the duration of hoarseness after tracheal intubation and to identify risk factors that may increase the duration of hoarseness. Methods We prospectively studied 3093 adult patients (aged 18–77 yr), over a 3 yr period who required tracheal intubation. Postoperative hoarseness was assessed on the day of operation and on postoperative days 1, 3, and 7 by standardized interview by the resident anaesthetist managing the patient. If postoperative hoarseness was still present on postoperative day 7, the patient was followed up until complete resolution. We evaluated age, gender, weight, Cormack grades, duration of intubation, and the anaesthetic agents used as factors affecting the duration of hoarseness after tracheal intubation. Results Hoarseness was observed in 49% of patients on the day of surgery and in 29%, 11%, and 0.8% on 1, 3, and 7 postoperative days, respectively. Multiple regression analysis showed that patient age and duration of intubation, but not gender, weight, Cormack grades, or the agents used, were significant predictors of increased duration of hoarseness after tracheal intubation. We found three patients with Arytenoid Cartilage dislocation (0.097%) in our study population. Conclusions The age of the patient and duration of intubation were significant factors in the duration of hoarseness after tracheal intubation. In addition, the incidence of Arytenoid Cartilage dislocation was 0.097%.
Huijing Bao - One of the best experts on this subject based on the ideXlab platform.
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spatial motion of Arytenoid Cartilage using dynamic computed tomography combined with euler angles
Laryngoscope, 2020Co-Authors: Huijing Bao, Xi Wang, Xi Chen, Zheyi Zhang, Jinan Wang, Peiyun Zhuang, Jack J Jiang, Azure WilsonAbstract:Objective To investigate the feasibility of dynamic computed tomography in recording and describing the spatial motion characteristics of the Arytenoid Cartilage. Methods Dynamic computed tomography recorded the real-time motion trajectory of the Arytenoid Cartilage during inspiration and phonation. A stationary coordinate system was established with the cricoid Cartilage as a reference and a motion coordinate system was established using the movement of the Arytenoid Cartilage. The Euler angles of the Arytenoid Cartilage movement were calculated by transformation of the two coordinate systems, and the spatial motion characteristics of the Arytenoid Cartilage were quantitatively studied. Results Displacement of the cricoid Cartilage was primarily inferior during inspiration. During phonation, the displacement was mainly superior. When the glottis closed, the superior displacement was about 5-8 mm within 0.56 s. During inspiration, the Arytenoid Cartilage was displaced superiorly approximately 1-2 mm each 0.56 s. The rotation angle was subtle with slight rotation around the XYZ axis, with a range of 5-10 degrees. During phonation, the displacement of the Arytenoid Cartilage was mainly inferior (about 4-6 mm), anterior (about 2-4 mm) and medial (about 1-2 mm). The motion of the Arytenoid Cartilage mainly consisted of medial rolling, and there was an alternating movement of anterior-posterior tilting. The Arytenoid Cartilage rolled medially (about 20-40 degrees within 0.56 s), accompanied by anterior-posterior tilting (about 15-20 degrees within 0.56 s). Conclusion Dynamic computed tomography recordings of Arytenoid Cartilage movement can be combined with Euler transformations as a tool to study the spatial characteristics of laryngeal structures during phonation. Level of evidence 4 Laryngoscope, 130:E646-E653, 2020.
J Cheetham - One of the best experts on this subject based on the ideXlab platform.
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ex vivo investigation of the effect of the transverse Arytenoid ligament on abduction of the Arytenoid Cartilage when performing equine laryngoplasty
New Zealand Veterinary Journal, 2019Co-Authors: M Chesworth, J Cheetham, O Brandenberger, Zoe Windley, James Schumacher, K Cochran, R J Piercy, Justin PerkinsAbstract:Aims: To investigate the effect of the transverse Arytenoid ligament (TAL) on abduction of the Arytenoid Cartilage when performing laryngoplasty. Methods: Modified prosthetic laryngoplasty was performed on right and left sides of 13 cadaver larynges. Increasing force was sequentially applied to the left Arytenoid Cartilage at 3 N intervals from 0-24 N, when the force on the right Arytenoid Cartilage was either 0 or 24 N, before and after TAL transection. Digital photographs of the rostral aspect of the larynx were used to determine the left Arytenoid abduction angles for these given force combinations and results compared before and after TAL transection. Longitudinal and transverse sections of the TAL from seven other equine larynges were also examined histologically. Results: Increasing force on the left Arytenoid Cartilage from 0-24 N produced a progressive increase in the angle of the left Arytenoid Cartilage (p < 0.001) and increasing force on the right Arytenoid Cartilage from 0-24 N reduced the angle of the left Arytenoid Cartilage (p < 0.001). Following transection of the TAL the mean angle of the left Arytenoid increased from 36.7 (95% CI = 30.5-42.8)° to 38.4 (95% CI = 32.3-44.5)°. Histological examination showed that the TAL was not a discrete ligament between the Arytenoid Cartilages but was formed by the convergence of the ligament and the left and right Arytenoideus transversus muscles. Conclusions: Transection of the TAL in ex vivo equine larynges enabled greater abduction of the left Arytenoid Cartilage for a given force. These results indicate that TAL transection in conjunction with prosthetic laryngoplasty may have value, but the efficacy and safety of TAL transection under load in vivo, and in horses clinically affected with recurrent laryngeal neuropathy must be evaluated. Abbreviations:Fmax: Force needed to maximally abduct the left or right Arytenoid; TAL: Transverse Arytenoid ligament.
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equine laryngoplasty sutures undergo increased loading during coughing and swallowing
Veterinary Surgery, 2010Co-Authors: T H Witte, J Cheetham, L V Soderholm, Lisa M Mitchell, Norm G DucharmeAbstract:Objectives: To report (1) the force required on a single laryngoplasty suture to achieve optimal abduction of the left Arytenoid Cartilage, (2) peak forces experienced by the suture during induced swallowing and coughing, and during 24-hour resting activity in a stall, and (3) peak forces during induced swallowing and coughing after left recurrent laryngeal nerve blockade. Study Design: Experimental study. Animals: Horses (n=8). Methods: Each laryngoplasty suture was instrumented with an E-type buckle force transducer to measure the force required for optimal intraoperative left Arytenoid Cartilage abduction. This was correlated with abduction observed postoperatively. Change in suture force from baseline was measured during induced coughing and swallowing, and during normal stall activity. Results: Optimal intraoperative Arytenoid abduction was achieved with a mean (±SD) force of 27.6±7.5 N. During saline-induced swallowing and coughing mean force on the suture increased by 19.0±5.6 N (n=233 measurements; 7 horses) and 12.1±3.6 N (n=31; 4 horses), respectively. Sutures underwent increased loading a mean of 1152 times in 24 hours. No change in suture force was observed with respiratory rhythm. Conclusion: Swallowing increases laryngoplasty suture force to a greater extent than coughing.
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implications of different degrees of Arytenoid Cartilage abduction on equine upper airway characteristics
Equine Veterinary Journal, 2008Co-Authors: Vineet Rakesh, J Cheetham, N G Ducharme, Ashim K Datta, A P PeaseAbstract: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.
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neuroanatomy of the equine dorsal cricoArytenoid muscle surgical implications
Equine Veterinary Journal, 2008Co-Authors: J Cheetham, C R Radcliffe, Norm G Ducharme, I Sanders, John W HermansonAbstract:Summary Reason for performing study: Studies are required to define more accurately and completely the neuroanatomy of the equine dorsal cricoArytenoid muscle as a prerequisite for developing a neuroprosthesis for recurrent laryngeal neuropathy. Objective: To describe the anatomy, innervation, fibre types and function of the equine dorsal cricoArytenoid muscle. Methods: Thirty-one larynges were collected at necropsy from horses with no history of upper airway disease and 25 subjected to gross dissection. Thereafter, the following preparations were made on a subset of larynges: histochemical staining (n = 5), Sihler's and acetylcholinesterase staining for motor endplates (n = 2). An additional 6 larynges were collected and used for a muscle stimulation study. Results: Two neuromuscular compartments (NMC), each innervated by a primary nerve branch of the recurrent laryngeal nerve, were identified in all larynges. Stimulation of the lateral NMC produced more lateral displacement of the Arytenoid Cartilage than the medial NMC (P<0.05). The medial NMC tended to rotate the Arytenoid Cartilage dorsally. Motor endplates were identified at the junction of the middle and caudal thirds of each NMC. If fibre type grouping was present it was always present in both NMCs. Conclusions: The equine dorsal cricoArytenoid muscle has 2 distinct muscle NMCs with discrete innervation and lines of action. The lateral NMC appears to have a larger role in increasing cross-sectional area of the rima glottidis. Potential relevance: This information should assist in planning surgical reinnervation procedures and development of a neuroprosthesis for recurrent laryngeal neuropathy.
