X-ray feature of pyloric stenosis is –
**Core Concept**
Pyloric stenosis is a condition characterized by the narrowing of the pyloric channel due to hypertrophy of the pyloric muscle, leading to gastric outlet obstruction. The characteristic X-ray feature is a result of this obstruction.
**Why the Correct Answer is Right**
The correct X-ray feature of pyloric stenosis is the "string sign" or "olive sign", which is caused by the narrowed pyloric channel. This sign is due to the thickened pyloric muscle, which creates a narrow, elongated channel that can be seen on an X-ray. The "olive sign" refers to the palpable, firm, and elongated pyloric mass, which is a result of hypertrophy of the pyloric muscle.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not describe a recognized X-ray feature of pyloric stenosis.
* **Option B:** This option is incorrect because it describes a feature of duodenal atresia or stenosis, not pyloric stenosis.
* **Option C:** This option is incorrect because it describes a feature of gastric ulcer or gastritis, not pyloric stenosis.
**Clinical Pearl / High-Yield Fact**
The "string sign" or "olive sign" is a classic radiographic feature of pyloric stenosis, and it is often associated with a palpable, firm, and elongated pyloric mass.
**Correct Answer:** C. The "string sign" or "olive sign" is a characteristic X-ray feature of pyloric stenosis.