i-Scan Endoscopy in the Detection of Minimal Change Esophagitis in Dyspeptic Patients With or Without Gastroesophageal Reflux Disease by Gerd Q Questionnaire and by 24 Hour pH Monitoring.

Background: The association of minimal change esophagitis (MCE) with gastroesophageal reflux (GERD) is controversy. High resolution endoscopy may improve the detection of minimal change lesion (MCL). i- Scan endoscopy (SE) provides high resolution images with modulation of images for a specific purpose.

Methods. All dyspeptic patients with or without GERD symptoms scheduled for endoscopy were recruited from February 2010 till July 2014. All completed the validated Thai version of GerdQ then underwent endoscopy. Forty normal volunteers were recruited for endoscopy and PHM test. The esophagus was examined by HD and SE with the TE-e mode sequentially. The captured images were independently evaluated for MCL (punctate erythema (PE), minute erosion (ME) and triangular lesion with elongated pit (EP) by three endoscopists. The agreement of > 2 endoscopists was accepted as a final result. All had PHM within 1 week after the endoscopy. GERD was diagnosed by LA grade A-D esophagitis and/or PHM with acid exposure time > the upper limit of volunteer and/or positive symptom index and/or positive Symptom Association Probability. MCE was diagnosed when PE, ME or EP or the combination of these were present.

The 40 normal volunteers were recruited for performing pH monitoring. The PHM data of 40 volunteers were analyzed to set the upper normal limit of total acid exposure time in our population. The mean + 2SD of total acid exposure time of volunteers was 1.9%.

Definition. GerdQ. The Thai version of GerdQ was translated from the English version. The contents of the GerdQ were tested by back translation from Thai to English by 5 personnel who are fluent in English and all showed the consistent contents. The reliability of the GerdQ was validated in 22 volunteers completing the questionnaire twice with 3 hours in between and showed no significant difference of the mean score (5.14+ 2.34 vs 6.23+ 1.57, p=0.07) and the number of subjects with GERD diagnosed by the GerdQ (2 vs 5, Fisher's extact test, p=0.21) .

GERD is diagnosed when total acid exposure time is more than 2% or positive symptom index (SI) or positive symptom association probability ( SAP ) or endoscopy revealed LA erosive esophagitis > grade A.