How can large stones pass through the narrow bile ducts?
An ultrasound scan cannot distinguish between a single large stone in the gallbladder, and multiple stones positioned close to each other. In the case of large cholesterol stones, repeated flushes can soften and gradually dissolve them until they are small enough to pass through the elastic bile ducts. Nature has similar examples where a large object goes through a narrow passage – a snake swallowing a meal larger than its head, or a mother giving birth to her child.
