Learning Modern Laryngeal Surgery in a Dissection Laboratory

This reproducible affordable laboratory setup can be used for laryngeal surgery that is closely similar to ex vivo animal laryngeal models. This laryngeal training center is an ideal setup for training in endoscopic and open laryngeal surgeries for technical refinement and teaching purposes. This type of laboratory setup could reproduce the learning curve in endoscopic and open laryngeal surgeries.

Demonstrating the procedure will be Dr.Andrea Manca, Dr.Davide Lancini, and Dr.Marco Fantini, residents from my unit. If possible, use a room with a sector table and a proper sink for ease of washing before and after the procedure. Procure a surgical light or traditional lamp that provides sufficient illumination and place a barrier across the table at the halfway point to split the table into two stations.

Then procure a biohazard waste container into which the porcine specimen and used materials will eventually be discarded. To prepare the endoscopic station, place the specimen on a proper support and position the laryngoscope at the end of the surgical table. Insert the appropriate laryngoscope for the selected laryngeal region into the specimen.

Expose the surgical target of interest and tighten the proper screw to fix the laryngoscope to the support. To expose the vocal folds, embed the tip of the laryngoscope anterior to the arytenoid cartilages pushing these structures in a lateral posterior direction to apply tension to the vocal folds. Place a suction system inside the specimen to extract the laser fumes and fix a wet gauze inside the inferior tracheal extremity of the larynx to avoid the emission of the carbon dioxide laser from the inferior part of the specimen.

Then place a wet gauze at the superior border of the larynx to protect the areas not involved in the dissection. Position the endoscope in front of the laryngeal specimen to guarantee that the participants will have the same perspective as that of the first operator using an endoscope holder to maintain the optic system in place. Confirm that all of the components are fixed and stable in their positions and place the 4K or full high definition monitor on the right side of the table connected to the microscope or to the endoscopic camera.

Place the laser on the left side of the table and connect the operating microscope to the carbon dioxide laser. Have the surgeon and all of the participants put on safety goggles before turning on the carbon dioxide laser. Then place a microlaryngoscopy set of surgical instruments on a table beside the first surgeon.

To prepare the open surgery station, place the specimen inside an open box on the other end of the sector table and adjust the surgical light so that it illuminates the surgical field. Then place a conventional two-dimensional camera above the surgical field and connect the camera to a 2D/3D monitor. To perform an open partial horizontal laryngectomy, use scissors and forceps to dissect the strap muscles along the midline and remove the pre-laryngeal tissue.

Rotate the larynx contralaterally and make an incision of the inferior constrictor muscle bilaterally along the lateral aspect of the thyroid cartilage. Retract the larynx medially and downward to protect the superior laryngeal pedicle before sectioning the thyrohyoid ligament. Bilaterally dissect the piriform sinus from the thyroid cartilage and the periglottic space as far as the inferior cornu of the thyroid cartilage and dissect the cricothyroid muscle.

Section the inferior cornu of the thyroid cartilage bilaterally to protect the recurrent laryngeal nerve. Use scissors to make the superior access along a line parallel to the superior border of the thyroid cartilage through the pre-epiglottic space. Use thumbs to apply pressure onto the laryngeal prominence while pulling the lateral laminae of the cartilage forward.

Use the scalpel to make the inferior access between the thyroid cartilage and the cricoid ring and modify the inferior access according to the selected type of open partial horizontal laryngectomy. To complete the dissection, make vertical incisions to connect the superior and the inferior accesses and cut the aryepiglottic folds, the false vocal cords, the true vocal cords, and the subglottic region. Modify the lines of incision according to the selected type of open partial horizontal laryngectomy and apply four polygalactin 910 stitches, one of which should be a median double between the cricoid cartilage and the hyoid bone through the base of the tongue.

The result of the inside out technique can be checked using a zero degree endoscopic telescope. In the last two sessions of the LARY-GYM course, the satisfaction of 14 of the 28 participants was determined through a dedicated questionnaire in which the participants responded to questions about their course experience on a scale from one to five as indicated in the table. All of these exercises can be easily simulated and repeated inexpensively with this type of laboratory setup in the presence of a master of the technique.

Following this procedure, we can test phonosurgery techniques such as the injection of hyaluronic acid into the vocal cords. The same setup can be used to test transoral robotic surgery for oropharyngeal and supraglottic tumors. Remember that it's mandatory to wear safety goggles when using the carbon dioxide laser device.