Biliary Microlithiasis

home > research > theories > where foci form

Biliary Microlithiasis - Theories

A Theory on Where Foci (Biliary Microlithiasis) Form

Most cystic ducts are smooth.  Some have varying lengths of small corrugated saccule like dilatations along the duct wall, valves of Heister.  Perhaps foci form in these corrugated sacculations.  A nidus develops in a small saccule from which grows a uniform sized .5 to 2 mm foci.  The near uniform size of foci suggests they completely form in the cystic duct saccule before migrating into the gallbladder or pass into the duodenum.  Foci unlikely form in the gallbladder as they have a near uniform size unchanged on repeat exams.  Also, “the same pain” and recurrent pancreatitis post cholecystectomy suggests they form in the cystic duct.  These particles likely pass through the cystic duct and ampulla where they may obstruct.  Intermittent right upper quadrant pain especially over long periods, suggests this fact. 

A Method That Might Prove These Foci are Biliary Microlithiasis.

Foci could be analyzed and confirmed as the same structures seen on rotational ultrasound and at ERCP aspiration.  Foci may be fragile, easily broken down or are hard, not easily disrupted.  ERCP aspiration may result in fragmentation of biliary microlithiasis so there would be a discrepancy in their appearance compared to the foci seen with rapid rotation.  Foci might be visualized by removing the gallbladder intact, then ultrasound the agitated specimen with all the contents to prove their presence.  The gallbladder is opened and examined with a magnifying lens.  Foci could blend in with bile and not be seen requiring meticulous retrieval by other methods.