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Use of the Scissor-Type Knife During the Peroral Endoscopy Myotomy Procedure for the Treatment of Achalasia
Published on: March 3, 2023
Pharyngeal observation via transoral endoscopy using a lip cover-type mouthpiece
Taro Iwatsubo1,2, Ryu Ishihara1, Kentaro Nakagawa1
1Department of Gastrointestinal Oncology, Osaka International Cancer Institute, Osaka, Japan.
Background And Aim:
Simultaneous and metachronous head and neck cancers are likely to develop in patients with current or previous esophageal cancer. The Valsalva maneuver facilitates the visualization of the hypopharyngeal area during endoscopic observation, but it requires transnasal endoscopy. We developed a novel Valsalva maneuver using transoral endoscopy with a lip cover-type mouthpiece.
Methods:
Between March 2018 and July 2018, 107 patients with current or previous esophageal cancer who were scheduled to undergo upper gastrointestinal endoscopy were included in our pilot study. We performed the Valsalva maneuver using our newly developed mouthpiece and transoral endoscopy in the patients and evaluated the hypopharyngeal region, including the postcricoid area and the posterior wall of the hypopharynx. The outcome measure was procedural success rate, which was graded as "complete," "incomplete," and "none."
Results:
Observation of the hypopharyngeal area was "complete" in 81 patients (76%) using the Valsalva maneuver. However, in 25 patients and in 1 patient, observation was "incomplete" and "none," respectively. Seven lesions were newly detected in seven patients during the study period.
Conclusions:
The Valsalva maneuver using transoral endoscopy with a lip cover-type mouthpiece is feasible for the visualization of the postcricoid area and the posterior wall of the hypopharynx. Particularly, this technique would contribute to early detection of head and neck cancers.
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