For a PA oblique esophagus projection (RAO position) with accurate positioning, January 2, 2023 by admin the patient is rotated until the midcoronal plane is at a 35- to 40-degree angle with the IR. the central ray is centered to the esophagus at the level of T6 to T7. an 11- × 14-inch (28- × 35-cm) IR is used. the patient drinks barium before the exposure only. See Answer the patient is rotated until the midcoronal plane is at a 35- to 40-degree angle with the IR.