Gallbladder pathology
For normal anatomy and scanning protocol
Cholelithiasis
Commonly called gallstones
Many people do not even realise they have gallstones unless they have experienced symptoms. Typically Right upper quadrant pain radiating to the back.
The 5 “F’s” fat, fertile, over forty ,female and fair are risk factors along with rapid weight loss, gallbladder stasis, genetic disorders that impair bile salt synthesis/secretion or increase cholesterol levels (serum or biliary), low HDL levels. Some Nationalities such as Scandinavians, Chileans and Mexican-Americans are at higher risk.
Ultrasound image- Small Gallstones on the posterior wall.
Ultrasound image- The stones move to the fundus when erect.
Ultrasound image-If a calculus is suspected, examine the gallbladder with the patient erect to confirm it is mobile
(and not impacted or a polyp).
If the patient cannot be examined erect, roll them between supine/decubitus. Consider what position will cause the calculus to move to the dependant portion of the gallbladder.
Ultrasound image- Multiple calculi almost filling the gallbladder.
Ultrasound image- A calculus impacted in the neck of the Gallbladder.
The Gallbladder has been unable to excrete for some time resulting in complex biliary stasis.Biliary sludge typically occurs before gallstones.
For a description of the different types of gallstones. (Primarily Cholesterol or Bilirubin Based)
Ultrasound image- The colour seen using power doppler is artifactual.
It is twinkle artifact secondary to reverberation in the bright crystaline material resulting from the bile concentration.
This will have a characteristic ‘bacon frying’ crackling noise using spectral doppler.
Ultrasound image- Mobile small gallstones moving into the fundus when the patient stands erect. It is the smaller stones that are at most risk of impacting in the neck and causing pain and inflammation.
Sludge
- The role of the gallbladder is to store and concentrate bile.
- Sludge is concentrated bile combined with the normal mucous secreted by the gall bladder. This then sediments out under the fresh bile entering the gallbladder.
- With modern high resolution ultrasound, it is normal to see some fine echogenic material ‘floating around’ within the gallbladder.
Ultrasound image- Complex material filling the gallbladder.
A calculus is impacted in the neck.
Ultrasound image- Subtle sludge with mild GB wall thickening and pericholic fluid. Increased vascularity of the wall seen with colour doppler.
Acute cholecystitis with biliary stasis.
Ultrasound image- Sludge almost filling the gallbladder. A single echogenic calculus is suspended within the sludge
Ensure there is no obstruction in the Gallbladder neck.
Mirizzi's Syndrome
Is very rare. It is when a stone impacting in the cystic duct or gallbladder neck causes extrinsic compression or obstruction of the common bile duct, causing jaundice.
For a great article on mirizzi syndrome
Polyps
There are varying types. Ultrasound is not able to determine which type.
- Adenomyosis 15-25% of benign polyps
- Cholesterol polyp Most common benign polyp (50-90%) Usually women (75%), 40-50 years old
- Granular cell tumor
- Hyperplastic / metaplastic polyp Common (25% of benign polyps)
- Inflammatory polyp 15% of benign polyps .Associated with chronic cholecystitis
- Villous papilloma Associated with metachromatic leukodystrophy in children and adults. May cause massive hemobilia
Ultrasound image- Multiple Polyps
Ultrasound image- A sessile mucosal polyp. You must also examine with the patient erect.
Ultrasound image- Highly suspicious Polyp in the gallbladder.
A large polyp is adjacent to the phrygian cap.
Cholecystitis
Acute cholecystitis is the fourth most common cause of hospital admissions for patients presenting with an acute abdomen in the US.Assess for a positive sonographic Murphy’s sign ( i.e., pain elicited by pressure over the sonographically located gallbladder), pericholecystic fat inflammation or fluid and hyperemia of the gallbladder wall at power Doppler.
Systemic diseases such as hepatic dysfunction, heart failure, or renal failure may lead to diffuse gallbladder thickening .
Cholecystitis is defined as inflammation of the gallbladder, commonly because of an obstruction of the cystic duct from gallstones (cholelithiasis). Most cases involve stones in the cystic duct (ie, calculous cholecystitis), with about 10% of cases representing acalculous cholecystitis.
Risk factors include increasing age, female sex, certain ethnic groups, obesity or rapid weight loss, drugs, and pregnancy.
Acalculous cholecystitis is related to conditions associated with biliary stasis, including debilitation, major surgery, severe trauma, sepsis, long-term total parenteral nutrition (TPN), and prolonged fasting. Other causes of acalculous cholecystitis include cardiac events; sickle cell disease; Salmonella infections; diabetes mellitus; and cytomegalovirus, cryptosporidiosis, or microsporidiosis infections in patients with AIDS.
The most common presenting symptom of acute cholecystitis is upper abdominal pain. The physical examination may reveal fever, tachycardia, and tenderness in the RUQ or epigastric region, often with guarding or rebound. However, the absence of physical findings does not rule out the diagnosis of cholecystitis.
Ultrasound image- Grossly distended gallbladder full of biliary sludge. Fundal calculi and a calculus impacted in the neck.
Ultrasound image- The thin echogenic rim visible inside the wall is gas suggesting significant infection.
Ultrasound image- Longitudinal view of a gallbladder with
a calculus (purple) impacted in the neck.
Resultant wall oedema (green)
Ultrasound image-Short axis or transverse view showing the gallbladder wall edema in cholecystitis.
Ultrasound image- Demonstrating the difference between high and low gain settings to assess for gallbladder contents.
The calipres approximate the wall oedema in this case of cholecystitis.
Cholangitis
Ultrasound image- Oedema of the gall bladder wall in acute cholecystitis associated with ascites.
Ultrasound image- This patient presented with extreme right upper quadrant pain. They had a history of gallstones. The bile ducts were inflamed which is referred to as Cholangitis. Try to identify any stones in the ducts and report their position.
Acknowledge: Mrs Alison Deslandes . AMS.
Adenomyomatosis
- Is characterized by epithelial proliferation, muscular hypertrophia and intramural diverticula (Rokitansky-Aschoff sinuses), which may segmentally or diffusely involve of the gallbladder.
- It is a benign condition that requires no specific treatment, occurring as an incidental finding in up to 9% of cholecystectomy specimens [6].
Ultrasound image- Phrygian cap at the Gall bladder fundus. This is a normal variant and should not be confused with a Rotikanski-Aschoff sinus.
Ultrasound image- The sonographic finding of cholesterol crystals, shown as ‘comet-tail’ reverberation artifacts within a thickened wall of the gallbladder strongly suggests this diagnosis.
Air may produce a similar artifact, however, patients with emphysematous cholecystitis are usually ill in contrast to those with adenomyomatosis.
MR imaging may be able to differentiate adenomyomatosis from gallbladder carcinoma by depicting Rokitansky-Aschoff sinuses
Gallbladder Carcinoma
Carcinoma of the gallbladder is the most common primary hepatobiliary carcinoma.It affects people more commonly over 65 years old with chronic cholecystolithiasis. The ultrasound appearance is that of a thickened gallbladder wall. It may extend into the liver. If a polyp is greater than 1cm single or multiple further investigation is warranted. Usually patients have coexisting stones.
Gallbladder Duplication
Double gallbladder is a rare congenital anomaly.
Double gallbladders are classified according to the Boyden’s classification .The two main types of duplications are vesica fellea divisa( bilobed gallbladder )and vesica fellea duplex ( true duplication), with two different cystic duct. The accessory gallbladder of ductular type may be adjacent to the normal organ in the gallbladder fossa or may be intrahepatic, subhepatic or within the gastrohepatic ligament. The true duplication is more common and occurs due to bifurcation of gallbladder primodium during the 5 th and early 6 th week of embryonic life.
The double gallbladders do not present with specific symptoms and the incidence of disease in this gallbladder is similar to its normal variant .Gallstone is the commonest complication occurring in one lobe but, both lobes can be involved. There is no increase in the incidence of disease in double gallbladder.
Ultrasound image- The differential diagnosis of double gallbladder include gallbladder fold, focal adenomyomatosis phrygian cap, intraperitoneal fibrous (Ladd’s) bands, choledochal cyst, pericholecystic fluid and gallbladder diverticulum.
References
- Rumack CM, Wilson SR, Charboneau JW. Diagnostic Ultrasound, 2nd ed. St.Louis: Mosby, 1998:175-200
- Zissin R, Osadchy A, Shapiro M, Gayer G. CT of a thickened-wall gallbladder. Br J Radiol 2003; 76:137-143
- Jung SE, Lee JM, Lee K, et al. Gallbladder wall thickening: MR imaging and pathologic correlation with emphasis on layered pattern. Eur Radiol 2005; 15:694-701
- Gore RM, Yaghmai V, Newmark GM, Berlin JW, Miller FH. Imaging of benign and malignant disease of the gallbladder. Radiol Clin N Am 2002; 40:1307-1323
- Boland GWL, Slater G, Lu DSK, Eisenberg P, Lee MJ, Mueller PR. Prevalence and significance of gallbladder abnormalities seen on sonography in intensive care unit patients. AJR 2000; 174:973-977
- Levy AD, Murakat LA, Abbott RM, Rohrmann CA. Benign tumors and tumorlike lesions of the gallbladder and extrahepatic bile ducts: radiologic-pathologic correlation. RadioGraphics 2002; 22:387-413
- Yoshimitsu K, Honda H, Jimi M, et al. MR diagnosis of adenomyomatosis of the gallbladder and differentiation from gallbladder carcinoma: importance of showing Rokitansky-Aschoff sinuses. AJR 1999;172:1535-1540