<prompt> Investigation of choice in pyloric stenosis-USGUGI seriesCTMRI  <response>: 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 