Dr Pedro Amarante Andrade Head & Neck 4 Larynx & Phonation Dr Pedro Amarante Andrade Marianne Bos-Clark

LARYNX/PHONATION SOURCES/READING Atkinson & McHanwell (2002) Basic Medical Science for SLT students London: Whurr Ch.16 Neck/Larynx Ch.17 Phonation Mathieson (2001) Greene & Mathiesosn’s The Voice & Its Disorders London: Whurr Ch.2 Larynx/ Upper resp. tract Ch.4 Voice and phonation Standard anatomy/physiology texts Internet

LARYNX/PHONATION Structure Lx: Cartilages Muscles Vocal folds Innervation Function: Normal voice production Voice quality

Breathing Protection Phonation Culture & Language Sciences – Information pack Breathing Protection Phonation Taken from Blausen.com staff: “Blausen galery 2014”. Wikiversity Journal of Medicine

THE LARYNX

LARYNX LOCATION Laryngeal cartilages. Taken from (Olias 2004)  

LARYNX – ANTERIOR & POSTERIOR VIEWS Laryngeal cartilages. Taken from (Olias 2004)  

LARYNX – POSTERIOR & LATERAL VIEWS Laryngeal cartilages. Taken from (Olias 2004)  

LARYNX- SAGITTAL VIEW From Gray's Anatomy 1918 edition. Public domain

LARYNX – POSTERIOR & FROM ABOVE From Gray's Anatomy 1918 edition. Public domain

THE LARYNX CARTILAGES

LARYNGEAL CARTILAGES 9 cartilages, 3 unpaired, 3 paired Thyroid cartilage Cricoid cartilage Epiglottis Arytenoid cartilages Minor cartilages: corniculate & cuneiform

EPIGLOTTIS Culture & Language Sciences – Information pack

EPIGLOTTIS Epiglottis in action Culture & Language Sciences – Information pack

THYROID Largest of the laryngeal cartilages; Titze IR. Physiologic and acoustic differences between male and female voices. J. Acoust. Soc. Am. 1989;85(4):1699-1707 Culture & Language Sciences – Information pack Largest of the laryngeal cartilages; Composed by two plate-like laminae; Laryngeal prominence – Adam’s apple; Houses the vocal folds;

THYROID – SAGITTAL VIEW Epiglottis Hyoid Bone Thyroid cartilage Vocal folds Arytenoid Culture & Language Sciences – Information pack Cricoid

CRICOID from Greek ‘ring-shaped’; Culture & Language Sciences – Information pack from Greek ‘ring-shaped’; Only complete ring of cartilage around the trachea; Sits on the top of the trachea;

ARYTENOIDS Pyramid-shaped pair of cartilages; Culture & Language Sciences – Information pack Pyramid-shaped pair of cartilages; Base slides on the top to of the cricoid; its lateral angle is called muscular process Its anterior angle is called the vocal process;

LARYNGEAL STRUCTURE Laryngeal membranes Thyrohyoid membrane Cricotracheal membrane Cricothyroid membrane ligament Laryngeal Joints Cricothyroid Cricoarytenoid

LARYNX – ANTERIOR VIEW

LARYNX – POSTERIOR VIEW

LARYNGEAL INLET Laryngeal vestibule infra/supra-glottis True VF False VF/vestibular folds Ventricular/laryngeal sinus

VOCAL FOLDS vocal fold (left/right); ventricular fold; trachea; epiglottis; arytenoid cartilage;

LARYNGEAL MUSCLES EXTRINSIC

EXTRINSIC LARYNGEAL MUSCLES Suprahyoid (elevators) Digastric Stylohyoid Mylohyoid Geniohyoid Infrahyoid (depressors) Sternohyoid Sternothyroid Omohyoid Thyrohyoid

LARYNGEAL MUSCLES Intrinsic

CRICOTHYROID MUSCLE (CT) 28.4.2017 Divided into two parts: Vertical/Straight and Oblique; Only intrinsic muscles innervated by the ‘external branch of the superior laryngeal nerve’ Contraction of vertical part of CT rotates the thyroid forward; Contraction of the oblique part pulls the thyroid forward; Cricothyroid joint;

OTHER INTRINSIC MUSCLES 28.4.2017 (TA) Thyroarytenoid muscles (IA) Interarytenoid muscle (LCA) Lateral Cricoarytenoid muscle ( PCA) Posterior Cricoarytenoid muscle

All above muscles are innervated by the ‘recurrent laryngeal nerve’ INTRINSIC MUSCLES and their function 28.4.2017 All above muscles are innervated by the ‘recurrent laryngeal nerve’

VOCAL FOLDS Histology

Principles of Voice Production. Titze, 2000 VOCAL FOLDS HISTOLOGY Principles of Voice Production. Titze, 2000

VOCAL FOLDS HISTOLOGY

VOCAL FOLDS: MEMBRANOUS AND CARTILAGINOUS PORTION

LARYNX Innervation

LARYNGEAL INNERVATION X VAGUS All innervation intrinsic laryngeal muscles Sensory structures larynx Superior laryngeal nerve: internal & external superior branches Left & right recurrent laryngeal nerve

LARYNGEAL INNERVATION X Vagus All innervation intrinsic laryngeal muscles Sensory structures Lx

LARYNGEAL INNERVATION X Vagus Superior laryngeal nerve: internal & external superior branches Left & right recurrent laryngeal nerve

PHONATION Own Work, following M. Hirano, The vocal cord during phonation, Igaku no Ayumi 80 (1968), no. 10. Author: Reinhard

PHONATION

VOICE ASSESSMENT SUBJECTIVE

PERCEPTUAL VOICE EVALUATION GRBAS (Hirano 1986) Rate the voice samples, for parameters Grade Rough Breathy Asthenia (weakness) Strain Scoring 0 = normal 1 = mild 2 = moderate 3 = severe If relevant, comment on amplitude & fundamental frequency or anything else you may notice about the voice LCSD08H | Voice and Fluency

PHONATION: VOICE QUALITY Judging voice quality on perceptual scales such as the GRBAS (Hirano 1986) G2R2B2A1S0 0=normal; 1=mild; 2=moderate; 3=severe

PHONATION: VOICE QUALITY GRBAS it: 0=normal; 1=mild; 2=moderate; 3=severe VOICE 01 VOICE 02 VOICE 03 VOICE 04 VOICE 05

EXAM PREP Explore the larynx on Anatomy TV Make sure you have a good understanding of the basic structure and function of the larynx, as well as the methods of examination used by ENT/Specialist SLTs