Filly's 12th Law
The thicker the gallbladder wall, the less likely it has anything to do with gallbladder disease.
I know that your first thought upon reading the above law is “WRONG.” You have been taught that chronic cholecystitis is the most common cause of a thickened gallbladder wall and thus has EVERYTHING to do with gallbladder disease.
Okay. But here are the points I am trying to make. Chronic cholecystitis is very highly associated with gallstones. The presence of a gallstone is virtually pathognomonic for chronic cholecystitis. (About 10-20% of the world population will develop gallstones at some point in their life and about 80% of them are asymptomatic.) Once one sees a gallstone, some gallbladder wall thickening is superfluous. However, in the absence of gallstones, gallbladder wall thickening, and especially marked gallbladder wall thickening is usually related to a disease in an organ other than the gallbladder. Of course I am talking about diffuse GB wall thickening. Focal gallbladder wall thickening is always suspicious for a gallbladder issue.
The normal thickness of the GB wall is usually less than 3 mm, provided that the patient has been fasting for 8-12 hours. The measurement is best carried out on the anterior wall where it abuts the liver, resulting in better intrinsic contrast.
Diffuse gallbladder wall (GB) thickening can result from a broad spectrum of pathological conditions. In most cases however, the cause can be determined by correlation of the associated imaging findings with the clinical presentation. The vast majority of very thick gallbladder walls are the result of liver disease, not gallbladder disease (usually secondary to hypoalbuminemia). Indeed, a markedly thickened GB wall is typically secondary to hepatitis, liver cirrhosis, congestive heart failure, renal failure, or pancreatitis.
The only intrinsic GB disease that I know of that causes marked wall thickening is xanthogranulomatous cholecystitis. Xanthogranulomatous cholecystitis is an uncommon variant of chronic cholecystitis characterized by xanthogranulomatous inflammation of the gallbladder. Intramural accumulation of lipid-laden macrophages and acute and chronic inflammatory cells is the hallmark of the disease. If you are not familiar with this disease it is because it is very uncommon