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Tolerability and efficacy of the concentration of iodine solution during esophageal chromoendoscopy: a double-blind
Tatsuhiro Gotoda1, Hiromitsu Kanzaki1, Yuki Okamoto1
1Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
Insights
Lower concentration iodine solution reduces patient discomfort during esophageal cancer screening. A 1% iodine solution is recommended over 2% for esophageal chromoendoscopy, offering similar diagnostic yield with less pain.
Area of Science:
- Gastroenterology
- Oncology
- Medical Imaging
Background:
- Esophageal chromoendoscopy with iodine solution is vital for detecting superficial esophageal cancer.
- Varied iodine concentrations have been reported, necessitating standardization for patient comfort and diagnostic efficacy.
Purpose of the Study:
- To evaluate patient discomfort associated with different iodine concentrations during esophageal chromoendoscopy.
- To compare the safety, detection yield, and color evaluation of 1% versus 2% iodine solutions.
Main Methods:
- A prospective, double-blind, randomized study involving 77 high-risk patients undergoing esophagogastroduodenoscopy (EGD).
- Patients were divided into two groups: 1% iodine solution (Group A) and 2% iodine solution (Group B).
- Pain measurements, safety, detection yield, and color evaluation (using CIELAB) were assessed as primary and secondary endpoints.
Main Results:
- Significantly lower heartburn and retrosternal pain were reported in the 1% iodine group (Group A) compared to the 2% group (Group B) (P = .02).
- Only 2 patients in Group A reported pain versus 9 in Group B.
- No significant differences were observed in detection yield or color evaluation between the groups; all patients completed the study without adverse events.
Conclusions:
- The 2% iodine solution causes significantly more pain than the 1% solution during esophageal chromoendoscopy.
- Diagnostic efficacy and image quality are comparable between the two concentrations.
- A 1% iodine solution is recommended for esophageal chromoendoscopy to minimize patient discomfort.
Background And Aims:
Esophageal chromoendoscopy with iodine solution is an important diagnostic method for the detection of superficial esophageal cancer. However, the concentration of iodine solution has differed among reports. This study aimed to evaluate patient discomfort with different iodine concentrations.
Methods:
We performed a prospective, double-blind, randomized study. We prospectively enrolled and analyzed 77 patients who were at high risk for esophageal carcinoma and scheduled to undergo EGD from March 2018 to January 2019. All patients were divided into 2 groups before the procedure to compare pain measurements: a 1% iodine solution group (group A) and a 2% iodine solution group (group B). The primary endpoint of this study was the difference in pain measurement between 1% and 2% iodine solution chromoendoscopy. Secondary endpoints were safety, detection yield, and color evaluation based on both the endoscopist's survey and color values, as determined using the Commission Internationale de l'Eclairage (CIELAB, Vienna, Austria) color evaluation system, in the iodine-faded and iodine-stained area of each group.
Results:
Heartburn and retrosternal pain in group A were significantly lower than those in group B (P = .02). Eleven patients reported heartburn and retrosternal pain (group A, 2; group B, 9). Four patients reported pain above the sternal angle and 7 below the sternal angle. There was no significant difference between the 2 groups with regard to detection yield, color evaluation by the endoscopist's assessment, or color values. No patients had any adverse events, and all safely completed this study.
Conclusions:
The 2% iodine solution resulted in significantly greater pain than the 1% iodine solution, and the color of the stained esophageal images of each group was the same from this study. Therefore, the 1% iodine solution is recommended for esophageal chromoendoscopy. (Clinical trial registration number: UMIN 000029796.).
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