This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Genito Urinary System, Subject name: Radiology
[{'content': 'Investigation of choice for Posterior urethral valves: \nSelect and explain. \nA. Micturating Cystourethrography (MCU), B. Ultrasound, C. Intravenous Pyelography, D. Retrograde urethrography', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. a (MCU). (Ref. Sutton Radiology 7th ed. 1017, 1061)- MCU is IOC for PU valve and VUR.Posterior urethral valves (PUV)# Varying degree of chronic urethral obstruction due to fusion and prominence of plicae colliculi, normal concentric folds of urethra.# Usually located in posterior urethra just distal to the level verumontanum.c;# It is the most common cause of severe obstructive uropathy in infants and children.# MCU is 'gold standard' in diagnosis of PUV.# Rx: Cystoscopic fulguration of the valves.Three types of PUV are described :", 'role': 'assistant'}]