Anatomic Study of Laser-Assisted Endoscopic Cricopharyngeus Myotomy

Objectives: Laser-assisted endoscopic cricopharyngeus muscle (CPM) myotomy has been used to correct dysphagia caused by CPM dysfunction. The aim of this study was to anatomically characterize this procedure in hopes of demonstrating its safety and efficacy. Methods: A Dohlman endoscope was used to isolate the CPM in 5 lightly preserved, thawed cadavers. A carbon dioxide laser at 10 W continuous power was used to section through the CPM in conjunction with a micromanipulator connected to an operating microscope. The specimens were then carefully dissected and photographed to demonstrate the anatomy of the pharyngoesophageal segment, including the location of the incision and the condition of the tissue planes. The CPM was harvested for histologic studies, sectioned, and prepared with modified Gomori trichrome stain. Results: Gross examination of the retropharyngeal region revealed the presence of intact buccopharyngeal fascia between the lasered region and the retropharyngeal space. Histologic analysis demonstrated sectioning of the CPM with preservation of this fascia layer. Placement of the endoscope was difficult in 1 cadaver, in which we were unable to properly identify the CPM. Conclusions: The carbon dioxide laser-assisted endoscopic CPM myotomy is a potentially anatomically safe and viable procedure when properly performed. However, the potential for violation of the retropharyngeal space is real.