2nd constriction in oesophagus is seen at the following site -: (A) Where it crosses left main bronchus, (B) Crossing of aorta, (C) At pharyngoesophageal junction, (D) Where it pierces the diaphragm
Answer is B. There are 4 esophageal constrictions. They are at 15cms, 22.5cms, 27.5cms and 37.5 to 40 cms, from the incisors. The second constriction is due to crossing of arch of aorta.