Anatomy of the Larynx

Johnathan D. McGinn, M.D.

Penn State Milton S. Hershey Medical Center Penn State College of Medicine October 18, 2007

Anatomy of the Larynx

Johnathan D. McGinn, M.D.

Penn State Milton S. Hershey Medical Center Penn State College of Medicine October 24, 2005

Case 1 • 55 year-old female with 2 pack per day for 35 year tobacco usage (70 pack-year) complains of 1 month history of hoarseness and cough. She has occasional chest discomfort and left arm weakness.

• Examination shows a hoarse voice. There is some fullness over the left supraclavicular area. Videostroboscopy was performed.

• Respiration

Function

BREATHING

• Deglutition • Phonation • Stress Maneuver

HULKING EATING SPEAKING

Evaluation

Larynx Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Larynx Framework • Rigid structure – 9 Cartilages – 1 Bone – Membranous sheets – Elastic tissue • Rigid structure allows for airway patency and muscular attachments

Larynx Framework Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Larynx Framework Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Gender Issues National Center for Voice and Speech, www.ncvs.org, 04/29/04

Elastic Membrane Cummings,

Otolaryngology – Head & Neck Surgery

, 1998 Wesley Norman, PhD, DSc

Tracheostomy www.portex.com

Laryngeal Musculature • Intrinsic muscles – Cricothyroid m.

– Thyroarytenoid m.

– Lateral cricoarytenoid m.

– Posterior cricoarytenoid m.

– Interarytenoid m.

• Extrinsic muscles Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Intrinsic Musculature Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Intrinsic Musculature Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Intrinsic Musculature Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Larynx Motion Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Extrinsic Musculature Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Extrinsic Musculature Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Pharyngeal Muscles Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Mucosal Surface Anatomy • Based on framework, membranous structures, and musculature • True and false vocal folds • Epiglottis • Ventricle • Saccule (appendix of ventricle) • Aryepiglottic folds • Pyriform sinuses

Mucosal Surface Anatomy Pyriform sinuses Ventricle Aryepiglottic fold True vocal fold False vocal fold Epiglottis

Mucosal Surface Anatomy Benjamin B,

Endolaryngeal Surgery

, Mosby, 1998.

Mucosal Surface Anatomy Cummings,

Otolaryngology – Head & Neck Surgery

, 1998 Benjamin,

Endolaryngeal Surgery

,1998

Mucosal Surface Anatomy Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Vocal Production • Power Source – Lung • Sound Producer – Vocal folds • Post-production Modification – Length and diameter supraglottic area – Shape of pharynx and oral cavity Eroschenko,

Atlas of Histology

,2000 .

Vocal Production • Closure of vocal folds • Development subglottic pressure • Subglottic pressure > Glottic closing pressure • Mucosal wave generated • Subglottic pressure < Glottic closing pressure • Airflow ceases Hirano,

Clinical examination of voice

, 1981

Vocal Quality Modal Whisper Breathy Harsh Creaky Falsetto

Case 2 48 year-old female who developed laryngitis several months ago after a viral illness.

She is employed as a laboratory technician and frequently works around volatile chemicals.

She continues to be hoarse despite the resolution of her cold symptoms.

Muscle Tension Dysphonia

Case 3 81 year-old female comes to your office complaining of not being able to sing in church like she did in past.

Her speaking voice also seems weaker than “normal.” Careful history-taking reveals some difficulties with swallowing, specifically coughing when she drinks liquids.

Vocal Fold Atrophy

Swallowing 1 2 • Closure of glottis by true and false vocal cords • Retropulsion of tongue base • Elevation of larynx beneath tongue base • Relaxation of cricopharyngeus

Laryngeal Innervation Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Laryngeal Innervation Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Laryngeal Innervation Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Laryngeal Innervation Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Case 4 57 year-old female underwent a left hemithyroidectomy for a benign adenoma.

Postoperatively, patient complains of hoarseness.

Her hoarseness was initally felt by her surgeon to be secondary to intubation irritation of larynx, but the symptoms persisted at the postoperative appointment.

She also notes occasional coughing with liquids, a sense of shortness of breath, and vocal fatigue.

She was referred to an otolaryngologist for evaluation.

Vascular Supply • Paired branches form external carotid system • Superior thyroid artery  Superior laryngeal a. • Inferior thyroid artery  Inferior laryngeal a.

Vascular Supply Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Vascular Supply • Veins parallel arteries Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Pathology

Pathology Benjamin B,

Endolaryngeal Surgery

, Mosby, 1998.

Case 1 • 55 year-old female with 2 pack per day for 35 year tobacco usage (70 pack-year) complains of 1 month history of hoarseness and cough. She has occasional chest discomfort and left arm weakness.

• Examination shows a hoarse voice. There is some fullness over the left supraclavicular area.

• CXR and Chest CT were performed

StudentBMJ.com

, October 21, 2003. http://www.studentbmj.com/back_issues/0302/education/63.html

Netter Frank H.,

Atlas of Human Anatomy

, 3 rd edition, 2003.

Radiographics. 2001 Sep-Oct;21(5):1275-81

The Far Side, Gary Larson Illustration credits: Netter, FH.

Atlas of Human Anatomy.

Icon Learning Systems, 2003.

Photography credits: Bruce Benjamin Sydney University

Endolaryngeal Surgery

, 1998