Apparatus (10) is provided, including an elongate carrier (24), configured to be advanced through an esophagus (20) of a subject. An anchor member (30) is coupled to a distal end of the carrier, and configured to be mounted in a stomach (32) of the subject in a vicinity of a lower esophageal sphincter (LES) (34) of the subject. An imaging capsule (26) is configured to move with respect to the carrier when the anchor member is in the vicinity of the LES. Other embodiments are also described.
