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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Medical treatment of gallstone indicated in A/E:
assistant
The correct answer is  For good results, medical therapy should be limited to radiolucent stones smaller than 5 mm in diameter. Stones larger than 15 mm in size rarely dissolve. Pigment stones are not responsive to UDCA therapy to produce a lamellar liquid crystalline phase in bile that allows a dispersion of cholesterol from stones. Ursodeoxycholic acid decreases cholesterol saturation of bile. UDCA may also retard cholesterol crystal nucleation.