Utility of Valsalva maneuver in the endoscopic pharyngeal observation

Metachronous cancer rate in the pharynx is high before and after the treatment of esophageal cancer. Endoscopic observation is difficult in the pharynx especially in the postcricoid area. Pharyngeal cancer in the postcricoid area has been often found in advanced stage. Valsalva maneuver has been reported to improve the visibility. From May 2017 we introduced a dedicated mouthpiece to conduct Valsalva maneuver. One hundred consecutive patients who had been observed throughout the pharynx by one endoscopist were enrolled. A total of 200 image files before and after introduction were made and reviewed by three endoscopists. We retrospectively evaluated the utility and safety of Valsalva maneuver. The visibility before introduction was Good in three cases, Moderate in 12 cases and Poor in 85 cases. Meanwhile, the visibility after introduction was Good in 58 cases, Moderate in 23 cases, and Poor in 19 cases (P