Related Experiment Video
Updated: Jul 16, 2026

The Flexible Rhino-Laryngoscope for Awake Nasotracheal Intubation
Published on: August 2, 2024
Prospective randomized trial of transnasal versus peroral endoscopy using an ultrathin videoendoscope in unsedated
Atsuhiko Murata1, Kazuya Akahoshi, Yorinobu Sumida
1Department of Gastroenterology , Aso Iizuka Hospital, Iizuka, Japan .ringer@hanafos.com
Aim:
The aim of this study was to compare the acceptance and tolerance of transnasal and peroral esophagogastroduodenoscopy (EGD) using an ultrathin videoendoscope in unsedated patients.
Methods:
A total of 124 patients referred for diagnostic endoscopy were assigned randomly to have an unsedated transnasal EGD (n = 64) or peroral EGD (n = 60) with local anesthesia. An ultrathin videoendoscope with a diameter of 5.9 mm was used in this study. A questionnaire for tolerance was completed by the patient (a validated 0-10 scale where '0' represents no discomfort/well tolerated and '10' represents severe discomfort/poorly tolerated).
Results:
Of the 64 transnasal EGD patients, 60 patients (94%) had a complete examination. Four transnasal EGD examinations failed for anatomical reasons; all four patients were successfully examined when switched to the peroral EGD. All 60 peroral EGD patients had a complete examination. Between the transnasal and peroral groups, there was a statistically significant difference in scores for discomfort during local anesthesia (1.5 +/- 0.2 vs 2.6 +/- 0.3, P = 0.003), discomfort during insertion (2.3 +/- 0.3 vs 4.3 +/- 0.3, P = 0.001), and overall tolerance during procedure (1.6 +/- 0.2 vs 3.8 +/- 0.2, P = 0.001). In all, 95% of transnasal EGD patients and 75% of peroral EGD patients (P = 0.002) were willing to undergo the same procedure in the future. Four patients in the transnasal EGD group experienced mild epistaxis.
Conclusion:
For unsedated endoscopy using an ultrathin videoendoscope, transnasal EGD is well tolerated and considerably reduces patient discomfort compared with peroral EGD.
Related Concept Videos
Endoscopic Procedures I: Esophagogastroduodenoscopy
During an EGD, the endoscope can be used to:
Endoscopic Procedures III: Video Capsule Endoscopy
Endoscopic Studies I: Bronchoscopy and Thoracoscopy
Bronchoscopy
Description
Bronchoscopy is a procedure that involves direct visualization of the larynx, trachea, and bronchi for diagnostic and therapeutic purposes. A flexible fiber optic or rigid bronchoscope is used to carry out the procedure. The fiber-optic bronchoscope is more frequently used due to...
Endoscopic Procedures IV: Sigmoidoscopy and Laproscopy
Sigmoidoscopy
Sigmoidoscopy is a diagnostic procedure that uses a flexible sigmoidoscope equipped with a light source and camera to examine the rectum and sigmoid colon. The procedure involves inserting the tube through the anus...
Endoscopic Studies II: Thoracocentesis
Description
Excess pleural fluid or air may accumulate in some respiratory disorders in the thoracic cavity. To treat pleural effusion, a physician conducts thoracentesis by carefully piercing the chest wall and entering...
Endotracheal Intubation I: Procedure
The ET tube comprises various components, including a standard adaptor to attach a bag-valve-mask (BVM) or ventilator, a cuff, a pilot balloon, and radiopaque markings along its length to measure the insertion distance. The tube sizes...

