What is acid reflux?

The most thoroughly evaluated classification scheme for esophagitis is the Los Angeles system, which categorizes mucosal injury as grade A, B, C, or D. However, it is important to note that the Los Angeles system does not consider strictures, hiatal hernia, or Barretts metaplasia; the endoscopist is required to describe these separately.

Los Angeles Endoscopic Grading Scheme for Esophagitis Severity
Grade A
One (or more) mucosal breaks no longer than 5 mm that do not extend between the tops of two mucosal folds.
Grade B
One (or more) mucosal breaks more than 5 mm long that do not extend between the tops of two mucosal folds.
Grade C
One (or more) mucosal breaks that are continuous between the tops of two or more mucosal folds but involve lesser than 75% of the circumference.
Grade D
One (or more) mucosal breaks that involve at least 75% of the esophageal circumference.