In CHPS which of the following is seen

In CHPS, non-bilious vomiting, metabolic alkalosis and aciduria is seen. The morphological features are due to hyperophy and hyperplasia of the circular muscle with some contribution by the longitudinal muscle. The hyperophied muscle lengthens and narrows the pyloric channel. Radiographically, there is the lengthening of the pyloric channel with smooth symmetrical narrowing. The hyperophied muscle bulges retrogradely into the antrum, creating a 'shoulder'. In infants, HPS ultrasound is the technique of choice in the diagnosis of HPS.