Technique of Endoscopic Cricopharyngeal Myotomy by CO₂ Laser and Its Surgical Effectiveness

Abstract

We performed a new paradigm of endoscopic cricopharyngeal myotomy (ECPM) by resection of the cricopharyngeal muscle as a modification of the conventional ECPM. The technique consisted of the following steps for the best results. 1. Postcricoid placement of a laryngoscope is performed. 2. A vertical midline incision is made in the mucosa covering the cricopharyngeal muscle with a CO₂ laser, and the muscle is well exposed under a microscope. 3. While grasping the cricopharyngeal muscle, its posterior aspect is widely separated from the buccopharyngeal fascia. 4. To avoid damage to the buccopharyngeal fascia is then needed. 5. While grasping the cricopharyngeal muscle with two clamps and keeping traction, a submucosal resection of the cricopharyngeal muscle is made with the CO₂ laser as widely as possible. 6. The resected area is covered with the mucosa and the initial mucosal incision is sutured horizontally. Our ECPM method will provide a more sufficient opening of the upper esophageal sphincter by eliminating the problem of postoperative adhesion of the cricopharyngeal muscle.
The effectiveness of our ECPM was evaluated based on neuromuscular theory. Objectives : The aim of this study is to clarify the effectiveness of our ECPM compared to the conventional transcervical cricopharyngeal myotomy (TCPM). Patients and Methods : Twenty-two head and neck cancer patients who underwent our ECPM or TCPM during cancer surgery were included. For immunopathological examination using acetylcholine esterase (AchE), specimens of 12 muscles surgically removed by TCPM and 10 muscles removed by our ECPM were promptly frozen and divided into longitudinal sections at the midline of each muscle. The AchE-stained areas of neuromuscular junctions were analyzed and calculated using an image binarization procedure. Results : There was no statistically significant difference in the AchE-stained areas between the two methods. Conclusions : Our ECPM technique has equal effectiveness to conventional TCPM.