For hiatus hernia, investigation of choice is
Barium swallow and meal examination give the best appreciation of gastro-oesophageal anatomy. The patient is in the Trendelenburg position to demonstrate barium in the fundus.Bailey and Love 26th edition Pg: 1015
Barium meal follow through
Barium meal upper GI
Barium meal upper GI in Trendelenberg position
Barium meal double contrast
C.V.S