Dissection Summary

Part 1 - Exposing the Pharynx & Esophagus 

• • Locate the intervertebral disc between C7-T1, and work from this level superiorly

    • • Remove any remaining musculature in the way

  • Lift the esophagus, pharynx, other viscera, and neurovasculature anteriorly to separate from the anterior vertebral column

  • Chisel through the C7-T1 intervertebral disc

  • Disarticulate the superior articular facets of C1 from the occipital condyles

  • Using an autopsy (Stryker) saw, complete a mid-sagittal section of the vertebral bodies of C1-C7

  • Expose the posterior pharynx and esophagus

Part 2 - Muscles of the Pharynx 

• • Clean the stylopharyngeus mm. 

  • Locate the glossopharyngeal nn. (CN IX)

  • Clean and distinguish the pharyngeal constrictor muscles

Part 3 - Cervical Ganglia 

• • Locate and clean the superior cervical ganglion at the C1/C2 level

  • Follow the cervical sympathetic trunk and locate:

    • • middle cervical ganglion ( C5/C6 level)

      • inferior cervical ganglion (C7/T1 level)

Part 4 - Carotid Sheath

• • Position (but do NOT remove) the superior cervical ganglion and sympathetic trunk laterally

  • Remove the posterior carotid sheath, and locate the:

    • • • internal jugular v.

        • common carotid a.

        • vagus n.

  • Locate the branches of the vagus n. (CN X) in this region

• • • • superior laryngeal n. (external and internal brs.)

      • recurrent laryngeal n.

• • Locate the carotid bifurcation. 

• • • • Differentiate between the external and internal carotid aa. 

      • Locate the carotid body and carotid sinus.

• • Follow the external carotid a. superiorly, and locate the 

• • • • superior thyroid a. 

        • superior laryngeal a.

• • Locate the thyrocervical trunk and identify:

• • • • inferior thyroid a.

        • inferior laryngeal a.

Part 5 - Divisions of the Pharynx 

• • Make a sagittal section along the posterior aspect of esophagus and pharynx 

  • Locate the:

    • •  nasopharynx

      • oropharynx

      • laryngopharynx

Part 6 - Larynx 

• • Looking at the posterior larynx, locate the:

    • • laryngeal inlet

      • ary-epiglottic folds

      • interarytenoid notch

  • Remove the mucosal layer of the laryngopharynx to expose the posterior aspect of the larynx

  • Identify the muscles of the posterior larynx

  • Reflect the inferior pharyngeal constrictor mm. laterally from the thyroid cartilages

  • Locate the cricothyroid m.

  • Remove the pharyngeal mucosa of the ary-epiglottic folds superior to the oblique and transverse arytenoid mm. to reveal the arytenoid cartilages and lateral crico-arytenoid mm.

  • Turn the donor supine, and locate the:

    • • thyrohyoid membrane

      • cricothyroid m.

  • Reflect the cricothyroid muscle unilaterally, and locate the cricothyroid joint

  • Mid-sagittally section the thyroid cartilage

  • With the donor prone, disarticulate (cut) a single cricothyroid joint and reflect the posterior edge of the ipsilateral thyroid lamina anteriorly  to reveal a closer view of the lateral crico-arytenoid m.

  • Make a midsagittal cut from the posterior laryngeal inlet inferiorly through the cricoid cartilage to open the larynx and visualize internal structures

  • Locate the laryngeal cartilages from an internal view

  • Locate the:

    • • laryngeal vestibule

      • vestibular folds

      • rima vestibuli

      • laryngeal ventricle

      • vocal folds

      • rima glottidis

      • infraglottic cavity

  • On one side, remove the mucosal lining of the larynx to expose the contents of the vocal folds and the remainder of the conus elasticus

    • • vocalis m.

      • vocal ligament

      • thyro-arytenoid m.

  • Uncover the quadrangular membrane, and its vestibular ligament

  • With the donor supine, investigate the relationships of the larynx to the hyoid bone and the trachea

  • Just proximal to the tracheal bifurcation, excise a section of the trachea, and examine its features