1.   The aetiology of cholesterol gall stones has not been completely elucidated.

2.   All patients had cholesterol gall stones.

3.   Subjects with cholesterol gall stones were reported to have alterations in the molecular species of phosphatidylcholine in bile, although the results of various studies are conflicting.

4.   The reduced metastability of biliary cholesterol in the gall bladder bile of patients with cholesterol gall stones has been well shown.

5.   In conclusion, patients with cholesterol gall stones produce less metastable hepatic bile measured by the evidence of shorter nucleation time.

6.   Patients without cholesterol gall stones, however, often have bile supersaturated with cholesterol.

7.   These findings suggest that factors, in addition to biliary cholesterol saturation, are responsible for the formation of cholesterol gall stones.

8.   Cholesterol nucleation is preceded by vesicle aggregation and fusion, and is believed to be an initial step in the formation of cholesterol gall stones.