Which imaging study is used for diagnosing Pyloric Stenosis?

Ultrasound is the preferred imaging study for diagnosing pyloric stenosis, particularly in infants. This is because ultrasound is non-invasive, does not involve radiation, and provides real-time imaging of the pylorus. In cases of pyloric stenosis, the ultrasound will typically reveal a thickened pyloric muscle and elongated pylorus, which are characteristic features of this condition.

The other imaging modalities listed, such as CT scans and MRIs, are more complex and involve exposure to radiation or extended scan times, making them less suitable for pediatric patients. Additionally, while X-rays of the upper gastrointestinal (GI) tract can provide some information, they are not the most effective method for visualizing the changes associated with pyloric stenosis and could miss the critical details that ultrasound captures. Therefore, the use of ultrasound is the gold standard for this specific diagnosis.