Investigation of choice in pyloric stenosis-

Ans. is 'a' i.e., USG o "The diagnosis of HP S is made by ultrasound scan or UGI series " - Sabistono "When olive cannot be palpated, ultrasonsgaraphy can diagnose the condition accurately in 95% of patients. Criteria for USG diagnosis include a channel length of> 16 mm and pylonic thickness of > 4 mm " - Schwartz