Drawings

View of indirect laryngoscopy from Henry Gray’s Anatomy of
the Human Body (1918)

The perspective of indirect laryngoscopy is commonly used for drawings in intubation education materials, even though indirect (mirror) laryngoscopy is rarely performed in current practice.  A drawing of the larynx from this angle makes all the structures appear as if they are on the same plane. In fact, the epiglottis is at a much higher (more cranial) location than the posterior cartilages (a.k.a.. the arytenoids) and these are more cranial than the vocal cords, which are deep within the larynx. Full visualization of larynx as shown here is rare with direct laryngoscopy.

Note that the tongue and vallecula are anterior (upper part of drawing); the orientation of the larynx in this image is the same as during direct laryngoscopy.  The epiglottis is at the top, the apex of the vocal cords (where the cords come together at the anterior commissure) is also up top.

The true vocal cord is labeled as “vocal fold,” and the false vocal cord (a mucosal fold) is labeled as “vestibular fold.”   The aryepiglottic folds connect the arytenoid cartilages to the epiglottis on either side.  The arytenoids are also called the posterior cartilages, and they are comprised of the cuneiform and corniculate cartilages.   Between the posterior cartilages is the interarytenoid notch. This landmark is the most posterior aspect of the laryngeal inlet, and critical to recognize during difficult laryngoscopy and tracheal tube insertion.   Johann Czermak (right), a pioneer in laryngology, performing indirect, mirror laryngoscopy in 1865. Note his left hand, which is being used to apply pressure to the thyroid cartilage and displace the larynx posteriorly into the line of sight.