Diagnosis often begins with prenatal ultrasound, which may reveal a "double bubble" sign, indicating fluid accumulation in the stomach and duodenum. After birth, further diagnostic tests include: - Abdominal X-ray: To visualize the "double bubble" sign more clearly. - Upper gastrointestinal series: A contrast study to confirm the location and extent of the obstruction. - Echocardiogram: To identify any associated cardiac anomalies.
