eMedicine Specialties > Radiology > Gastrointestinal
Cholecystitis, Acute: Imaging
Updated: Feb 4, 2009
Radiography
Plain abdominal radiograph of a 68-year-old woman who presented with acute abdominal pain. There are multiple calculi distributed in a pyriform shape in the right upper quadrant; these are suggestive of gallstones. Gallstones were diagnosed during sonography several months earlier. A clinical diagnosis of acute cholecystitis was made. However, the plain radiograph also shows features of a pneumoperitoneum. At laparotomy, a perforated cecal carcinoma was found. There were no findings of acute cholecystitis.
(Left) Plain radiograph of a 57-year-old woman presenting with right iliac fossa pain and mild fever shows large laminated opacities in the right iliac fossa (RIF); these findings suggest gallstones (arrow). Two smaller nonlaminated oval opacities are present more medially; these were interpreted as calculi in the cystic duct. Ultrasonography revealed a Reidel lobe of the liver. The gallbladder was located in the RIF and contained several calculi; however, no ultrasonographic features of acute cholecystitis were observed. The right kidney was also placed in the RIF, in a more medial location. Two calculi were present—one each in the upper and lower pole calices. (Right) Intravenous urogram shows a low-lying right kidney with calculi in the upper and lower pole calices. Urine culture revealed Escherichia coli. The patient's condition responded to a course of antibiotics. This example shows that an acute pyelonephritis can clinically mimic acute cholecystitis. With a Reidel lobe, the gallbladder may be located in the RIF, and an acute cholecystitis may mimic appendicitis or other RIF pathology.
Plain abdominal radiograph in a 49-year-old diabetic woman shows air within the gallbladder lumen due to emphysematous cholecystitis (arrow).
Plain abdominal radiograph in a patient with a clinical diagnosis of acute cholecystitis. The diagnosis was confirmed by means of abdominal ultrasonography. The radiograph shows faint opacities in the region of the gallbladder fossa and dilated loops of small bowel in the epigastrium and mid abdomen secondary to localized ileus.
This patient presented with acute cholecystitis, as confirmed at imaging. His pain resolved over a few days, but mildly elevated bilirubin levels persisted. Endoscopic retrograde cholangiopancreatographic (ERCP) study shows smooth narrowing of the bile duct (arrow) at the site of insertion of the cystic duct (Mirizzi syndrome). Note the small calculus in the cystic duct.
Findings
For patients with acute cholecystitis (AC), an acute plain abdominal radiograph is obtained primarily to exclude other diagnoses. Disorders such as empyema of the gallbladder (GB) and gallstone ileus may be suggested by findings on plain radiographs. Likewise, porcelain GB and milk-of-calcium bile have fairly characteristic appearances (see Images 1-5).
The plain radiograph may reveal dilated loops of the small bowel in the right upper quadrant; these findings may mimic those of small-bowel obstruction. Rarely, the GB is identified as a soft tissue mass.
On abdominal plain radiographs, the following signs should be assessed: opacities projected over the GB; linear calcifications in GB walls; GB enlargement; focal gas collections within the GB; and air-fluid levels in the GB lumen.
Plain radiographs may reveal gallstones, which are radiopaque in 15-20% of patients.9 Gallstones appear as single or multiple pyramidal, faceted, or cuboidal calcifications located in the right upper quadrant. Calcification may be central, homogeneous, or rimlike. When multiple gallstones are seen, the stones are clustered and are usually faceted. On erect images, stones may be layered in the dependent portion of the GB.
Occasionally, stellate radiolucencies are seen in the area of GB. These reflect gas-containing fissures within the GB calculi. This finding is referred to as the Mercedes-Benz sign. Gas in the GB wall or lumen is a feature of emphysematous cholecystitis. Calcification of the GB wall, or porcelain GB, is an indicator of chronic cholecystitis.
Biliary sludge of high calcium content, or limy bile, is also a feature of chronic cholecystitis. Gas may be seen in the bile ducts in cystocutaneous or cystoenteric forms with fistulous complications. The gallstone may pass through such a fistula into the gut and cause gallstone ileus. The stone usually has to be 25 mm in diameter to cause ileus. The ileum near the ileocecal junction is the most common site.
Emphysematous cholecystitis occurs as a complication of acute acalculous cholecystitis (AAC) in more than 50% of cases. Air is readily seen on plain abdominal radiographs. On upright radiographs, an air-fluid level in the right upper quadrant may be seen. This finding represents gas within the GB lumen admixed with inflammatory fluid, sludge, or both. Air within the wall of the GB appears more curvilinear. Gas visualized in the GB in the setting of AAC is highly associated with complications such as gangrene and perforation.
Oral cholecystography was employed in the past, but it no longer has a role in the diagnosis of AC. In cases in which the cystic duct is obstructed, the GB cannot be visualized. In patients who have recovered from an episode of AC, an oral cholecystogram may show single or multiple lucent-filling defects caused by calculi in an opacified GB. These usually are gravity-dependent; however, stones with a high cholesterol content and those containing air may float. Mobility is demonstrated by a change in position on supine and upright images. Compression images may be necessary to displace bowel gas.
Degree of Confidence
For patients with gallbladder disease, plain abdominal radiographic findings are nonspecific and are not useful in differentiating between biliary colic and acute cholecystitis. Plain radiography has been superseded by ultrasonography for such patients. Nevertheless, it still has value in cases in which the GB is not definitively identified by sonography. Emphysematous cholecystitis may be recognized easily on plain films. Sonography may be used in cases in which calcifications in the right upper quadrant are not of typical appearance or location.
Oral cholecystography has no role in the diagnosis of AC. However, in a more chronic setting, such as in cases involving gallstones, certain findings are characteristic; when such findings are present, no further imaging is required. Oral cholecystographic assessment of the number and size of gallstones is more accurate than sonography. The accuracy of oral cholecystography in the detection of gallstones is 85-90%.15
False Positives/Negatives
On plain abdominal radiographs, small bowel dilatation in the right upper quadrant caused by acute cholecystitis may be confused with small bowel obstruction.
The differential diagnosis for gallstones includes renal calculi, which are related to renal outline and which may be separated on oblique images if necessary. Only 50% of pigment stones and 20% of cholesterol stones contain sufficient calcium to be visible on plain radiographs. Gas in the biliary system must be differentiated from abscess or gas-forming collections in the gallbladder (GB) fossa. Ultrasonography may prove useful in such cases.
Porcelain GB has the characteristic appearance of eggshell calcification in the right upper quadrant. Other right-upper-quadrant calcifications, such as hepatic granulomas, tumor calcification, costal cartilage calcification, calcified mesenteric lymph nodes, and hepatic or renal artery aneurysms, are rarely confused with GB calculi.
A nonmobile filling defect seen on an oral cholecystogram may be an adherent stone, but it must be differentiated from polyps and adenomyomas; primary or metastatic tumors, heterotopic gastric mucosa, and pancreatic mucosa are more unusual conditions that may have a similar appearance. Calcified stones may be obscured by contrast material in the GB. Nonvisualization of the GB may have various causes, including drug-compliance failure or a change of drugs; intestinal resections; liver diseases; poor timing; cholestasis; and acute pancreatitis.
Computed Tomography
Findings
For cases of acute cholecystitis (AC), CT findings include the following: gallstones within the GB, the cystic duct, or both; more than 3 mm of focal or diffuse thickening of the GB wall in a noncontracted GB; indistinct liver-GB interface; fluid in the GB fossa in the absence of ascites; enlargement of the GB, with the transverse diameter measuring more than 5 cm; infiltration of the surrounding fat; increased bile attenuation, caused by biliary sludge; and GB mucosal sloughing.10,11,16,17
A low-attenuating ring surrounding the GB may be indicative of edema of the outer layer of the GB wall, or it may suggest the accumulation of fluid in the GB fossa. In hemorrhagic cholecystitis, the attenuation values of the GB contents may be abnormally elevated.
Contrast-enhanced CT shows enhancement of the GB wall and the adjacent liver. Inflammatory reaction in the pericholecystic fat is well seen on contrast-enhanced CT scans. This is a specific CT sign for AC. The inflammatory reaction is seen as streaky or bandlike areas of attenuation of soft tissue extending from the GB wall into the surrounding fat.
CT may be useful in the diagnosis of acalculous cholecystitis by showing the various signs described. However, CT may be difficult to perform because of the patients' poor condition.
In cases of emphysematous cholecystitis, CT may demonstrate intramural and intraluminal air within the GB better than plain abdominal radiography can. However, CT is not strictly needed for the diagnosis.
In diagnosing AC, CT criteria may be classified as major and minor. The diagnosis of AC requires the presence of 2 major criteria or 1 major and 2 minor criteria. This classification is particularly helpful in the diagnosis of acalculous AC. Major criteria include the following:
- GB wall thickening of greater than 3 mm
- A halo surrounding the GB, resulting from edema of the GB
- Extension of inflammation to the GB fossa
- Pericholecystic fluid in the absence of ascites
- GB mucosal sloughing
- Intramural GB gas
Minor criteria include GB dilatation, with the transverse diameter being greater than 5 cm, and sludge in the GB.
Degree of Confidence
Mucosal sloughing and intramural gas are specific signs of acute cholecystitis, but these are seen infrequently. The reported sensitivity and specificity of CT findings are 90-95%. CT is more sensitive than ultrasonography in the depiction of a pericholecystic inflammatory response and in localizing pericholecystic abscesses, pericholecystic gas, and calculi outside the GB lumen.
False Positives/Negatives
In cases of complicated acute cholecystitis, some CT features may mimic those of GB carcinoma. The features that may be confused with a carcinoma include diffuse or focal thickening of the GB wall and inflammatory infiltrate of the surrounding fat.
Magnetic Resonance Imaging
Nonenhanced CT scans through the gallbladder (GB) shows an indistinct GB wall. Contrast-enhanced CT scan (bottom) shows an inflammatory reaction in the pericholecystic fat, which is seen as streaky or bandlike soft-tissue areas of attenuation extending from the GB wall into the surrounding fat. Note the loss of the interface between the GB and surrounding soft tissue on both the nonenhanced (top) and enhanced (bottom) scans. Note also the striking enhancement of GB and pericholecystic tissues following the use of intravenous contrast material.
Acute cholecystitis mimic. Series of ultrasound and CT images are shown of a 36-year-old woman with severe right hypochondriacal pain. The gallbladder wall is thickened with a suggestion of the triple wall sign. There is a streak of pericholecystic fluid at the inferior aspect of the gallbladder. An ultrasound of the Murphy sign was negative. No gallstones were seen. There were no predisposing causes of an acalculous acute cholecystitis. A supine CT showed signs of inflammation in the region of the duodenum, but the duodenal wall was not well seen. However, further CT sections in the right decubitus position showed spasm and thickening of the wall of the first part of the duodenum. Endoscopy revealed an acute penetrating duodenal ulcer.
Acute cholecystitis mimic. Series of ultrasound and CT images are shown of a 36-year-old woman with severe right hypochondriacal pain. The gallbladder wall is thickened, with a suggestion of the triple wall sign. There is a streak of pericholecystic fluid at the inferior aspect of the gallbladder. An ultrasound of the Murphy sign was negative. No gallstones were seen. There were no predisposing causes of an acalculous acute cholecystitis. A supine CT showed signs of inflammation in the region of the duodenum, but the duodenal wall was not well seen. However, further CT sections in the right decubitus position showed spasm and thickening of the wall of the first part of the duodenum. Endoscopy revealed an acute penetrating duodenal ulcer.
Findings
In cases of acute cholecystitis (AC), MRI may depict the same pathologic features as CT does. Increased blood flow and capillary leakage resulting from inflammatory change are best exhibited by the use of gadolinium enhancement, particularly with fat-suppression techniques. Various morphologic changes may be observed (see Images 18, 23-24, 26).12,13,18,19,20,21,22
With T1-weighted gadolinium-enhanced images, prominent enhancement is seen along the mucosal layer of the gallbladder (GB) wall; on delayed images, this enhancement progresses to involve the whole thickness of the GB wall. A greater than normal degree of enhancement of the GB wall correlates well with the presence of AC. GB wall thickening is well depicted on both T1- and T2-weighted images. Transient liver enhancement is shown on immediate postgadolinium images, particularly T1-weighted and fat-suppressed images of the gallbladder fossa.
GB calculi are well seen on T2-weighted images, as is pericholecystic fluid. Intramural abscesses appear as areas of high signal foci on T2-weighted and fat-suppressed images.
Periportal high signal intensity is a nonspecific finding that is occasionally seen.
In hemorrhagic cholecystitis, which is more common in cases of acalculous cholecystitis, blood breakdown products may be identified on nonenhanced MRIs. Because of the specific signal-intensity characteristics of blood products on T1- and T2-weighted images, the age of the hemorrhage may be determined.
A magnetic resonance cholangiopancreatography (MRCP) protocol may show calculi in the GB, cystic duct, and CBD.
Gadolinium-based contrast agents (gadopentetate dimeglumine [Magnevist], gadobenate dimeglumine [MultiHance], gadodiamide [Omniscan], gadoversetamide [OptiMARK], gadoteridol [ProHance]) have been linked to the development of nephrogenic systemic fibrosis (NSF) or nephrogenic fibrosing dermopathy (NFD). For more information, see the eMedicine topic Nephrogenic Fibrosing Dermopathy. The disease has occurred in patients with moderate to end-stage renal disease after being given a gadolinium-based contrast agent to enhance MRI or MRA scans.
NSF/NFD is a debilitating and sometimes fatal disease. Characteristics include red or dark patches on the skin; burning, itching, swelling, hardening, and tightening of the skin; yellow spots on the whites of the eyes; joint stiffness with trouble moving or straightening the arms, hands, legs, or feet; pain deep in the hip bones or ribs; and muscle weakness. For more information, see the FDA Public Health Advisory or Medscape.
Degree of Confidence
For the diagnosis of acute cholecystitis, the sensitivity and accuracy of gadolinium-enhanced MRI techniques are higher than they are with ultrasonographic techniques. The MRI techniques may detect pericholecystic fluid with greater accuracy than is possible with ultrasonography. MRI has much greater sensitivity for the detection of CBD calculi than ultrasonography has.
False Positives/Negatives
There are a multitude of causes of increased thickness of the GB wall (see Ultrasound). Both GB polyps and gallstones may float and appear as signal voids. However, unlike gallstones, polyps may demonstrate enhancement with the use of a gadolinium-based contrast agent. Contrast enhancement may also occur in cases of chronic cholecystitis, but mural enhancement is more pronounced on delayed images than on other images, and pericholecystic enhancement is minimal.
Ultrasonography
Longitudinal oblique sonogram through the gallbladder shows a calculus at the neck of the gallbladder with acoustic shadowing and thickening of the gallbladder wall (arrow).
Longitudinal and axial scans through the gallbladder show layering of sludge (S) in the gallbladder lumen.
Oblique and longitudinal sonograms through gallbladder shows marked laminated sonolucent thickening of the gallbladder wall, sludge, and edema (arrow).
Axial scan through the gallbladder shows marked thickening of the gallbladder wall, with the lumen of the gallbladder full of sludge.
This 26-year-old man known to be HIV positive presented with pain in the right upper quadrant and mild jaundice. Axial sonogram through the gallbladder and pancreas shows sludge within the gallbladder and the lower common bile duct (CBD). A diagnosis of acalculous cholecystitis was confirmed. Arrow indicates the CBD; A, aorta; GB, gallbladder; IVC, inferior vena cava; P, pancreas; and S, splenic vein.
Acute emphysematous cholecystitis. Color Doppler images of the gallbladder of an 82-year-old male with diabetes mellitus who presented with abdominal distention and vomiting. Ultrasound shows a markedly thickened gallbladder wall, which is hypervascularized. There are no gallstones, but note the presence of air in the anterior wall of the gallbladder (arrow).
Findings
Sonographic features of acute cholecystitis (AC) include the following (see Images 6-15, 19-22, 25):
- Calculi in the gallbladder (GB), present in more than 90% of patients (calculi may be difficult to detect in the Hartmann pouch or cystic duct)
- Anterior GB wall thickness of more than 3 mm
- Positive Murphy sign (pain on compression of the GB with the ultrasound probe)
- Pericholecystic fluid in severe cases (indicative of actual or impending perforation)
- Echo-poor halo in or around the GB wall or striated GB wall (indicative of edema)
- Nonvisualization of the GB in a truly fasting patient (strong evidence of GB disease)
- Acalculous cholecystitis (5% of cases not associated with gallstones)
- GB distention (about 93% of patients with GB volume >70 mL have AC)
- Increased periportal echogenicity (presumably the result of a local inflammatory infiltrate)
- Loss of definition of GB margins
- Intraluminal wall desquamation, resulting in a lacelike lumen
- Hypervascularization of the GB wall on color-flow and power Doppler images, associated with GB-wall thickening on gray scale imaging
- Hypervascularization without GB wall thickening possible in cases of AC
In children, AC may be acalculous, with increased GB wall thickening, signs of hydrops, a positive sonographic Murphy sign, and an increase in the diameter of the CBD as a result of sludge.
In empyema of the GB, ultrasonography may reveal calculi within the lumen of the GB. Occasionally, the impacted calculus may be identified. The GB may be distended and tender to pressure from the sonographic probe. Within the GB lumen, gravity-dependent layering of pus, debris, or bile may be observed. Particulate matter may appear as bright medium to coarse echoes without shadowing.
With acute emphysematous cholecystitis, gas in the lumen of the GB is hyperreflective, with a distal reverberation artifact in the GB lumen. Intramural gas is characterized by hyperreflective foci in the GB wall, with or without a reverberation artifact. An effervescent GB may be seen; in such cases, a large number of bubbles rise from the dependent part of the GB like gas bubbles in a glass of champagne. The differential diagnosis includes various causes of pneumobilia.
There are major and minor ultrasonographic diagnostic criteria for the diagnosis of AC. Two major or 1 major and 2 minor criteria need to be present to achieve a diagnosis. This classification is particularly useful with AAC. The major criteria include the following:
- GB wall thickening of more than 3 mm
- A striated GB wall
- A positive sonographic Murphy sign
- Mucosal sloughing
- Pericholecystic fluid
- Intramural gas
Minor criteria include sludge within the GB and GB dilatation of greater than 5 cm in transverse diameter.23,24,25,26,27
Degree of Confidence
For the diagnosis of acute cholecystitis (AC), ultrasonography is rapid, noninvasive, affordable, and sensitive. Because ultrasonography may be performed at the bedside, it is particularly useful in making the diagnosis of AC in hospitalized patients, who may be very ill; dependent on a respirator; or recovering from surgery or various medical problems. The sensitivity and specificity of ultrasonography in the diagnosis of AC are 81-100% and 60-100%, respectively.28
False Positives/Negatives
Ultrasonography may be inaccurate in the diagnosis of acute cholecystitis (AC) in hospitalized patients, especially in patients who have acalculous cholecystitis. None of the sonographic criteria for diagnosing AC (eg, cholelithiasis, thickened GB wall, nonshadowing echoes, sonolucent stripes, pericholecystic fluid) are specific. Differentiating acute cholecystitis from chronic cholecystitis is possible in only 26% of patients. In 74% of patients, therefore, it is not possible to differentiate between acute and chronic cholecystitis on the basis of ultrasonographic findings. AC is presumed to be present if ultrasonography reveals no other apparent cause of abdominal pain.
The ultrasonographic Murphy sign is present in only 33% of patients with acute gangrenous cholecystitis. When gas is prominent in cases of emphysematous cholecystitis, the GB may be mistaken for a bowel loop because of increased echogenicity and shadowing.
The following are causes of increased GB wall thickness6 :
- Fasting (transient GB wall thickening present in about 3.5% of fasting patients)
- Poor distention (postprandial)
- Artifact on oblique sections
- Acute cholecystitis
- Chronic cholecystitis
- Carcinoma GB
- Xanthogranulomatous cholecystitis
- Acquired immunodeficiency syndrome
- Hyperplastic cholesterolosis
- GB varices
- Adenomyomatosis
- Leukemia-GB infiltration
- GB perforation
- GB torsion
- Oriental cholangiohepatitis
- Hepatic clonorchiasis
- Cholecystenteric fistula
- Focal obstruction to GB lymphatic drainage (eg, nodes at the porta)
- Hepatitis (80%)
- Cirrhosis
- Acute alcoholic abuse (severe GB wall thickening is often present after an alcoholic binge; may make the GB difficult to define)
- Portal hypertension
- Veno-occlusive disease
- Congestive cholecystopathy in chronic liver disease
- Hepatoportal sclerosis
- Infectious mononucleosis
- Extrinsic causes, systemic causes
- Hypoproteinemia
- Ascites
- Acute pancreatitis
- Acute myelogenous leukemia
- Sepsis
- Graft-versus-host reaction, bone marrow transplantation
- Brucellosis
- Systemic venous hypertension
- Right-sided heart failure
- Acute pyelonephritis (GB wall thickening secondary to adjacent inflammatory process; similar to that seen in pancreatitis and peptic ulcer disease)
- Renal failure
- Myeloma
- Appendicitis
- Peptic ulcer disease
- Infusion with interleukin-2 (IL-2) in HIV infection (symptomatic GB wall thickening during IL-2 infusion may exactly mimic other forms of acalculous cholecystitis, except when IL-2–associated GB wall thickness resolves after the cessation of therapy; surgical treatment not required)
Mimics of gallstones include the following6 :
- Partial volume effects, usually caused by impression by the duodenum
- Misidentification of the GB
- Fluid-filled bowel associated with gas, a hepatic or renal cyst, debris, hemorrhage, or a combination of these factors
- Nonvisualization of the GB in a fasting patient (presence of shadowing foci in the GB bed strong presumptive evidence of GB disease: wall-echo-shadow [WES] triad useful in this setting; complex consists of 2 parallel arcs of echogenic lines, with an interspaced anechoic space; echogenic lines represent the GB wall and the leading edge of the gallstone separated by anechoic bile; WES sign useful in differentiating a contracted diseased GB from other conditions with similar appearance [eg, porcelain GB, emphysematous cholecystitis, air-filled bowel])
- Reverberation echoes from folds in the GB neck
- Respiratory motion artifact (not usually a problem with real-time scanners)
- Shadows arising directly anterior or posterior to the GB (eg, rib)
- Junctional mucosal fold
- Clips in the cholecystectomy bed (patients may be unable to remember having undergone previous cholecystectomy or may be unaware that GB has been removed)
- Inspissated bile sludge, commonly seen in ill patients
- Any cause of an intraluminal filling defect
- Pseudosludge (the artifactual appearance of layering sludge caused by the section thickness and side-lobe artifact; these artifacts may be reduced by appropriate focusing, by centering the GB in the field of view, and by optimizing the gain settings)
- Adenomyomatosis and cholesterolosis (forms of hyperplastic cholecystosis; usually asymptomatic, but symptoms may occur because of associated gallstones)
- Emphysematous cholecystitis and porcelain GB (may cause patchy shadowing, which occasionally is present without associated gallstones; air and calcification echogenic and cause shadowing)
- Echogenic bile (often associated with biliary stasis or bile duct obstruction; echogenicity varies, but usually no shadowing present)
- Polyps within the GB (vary in size and echogenicity but do not show shadow; differentiation from adherent gallstones may be difficult)
Nonshadowing mobile intraluminal GB masses may be present6 :
- Calculi
- Tumefactive sludge
- Cholesterol crystals
- Pseudosludge, artifact
- Food and/or feces
- Blood
- Pus
- Fibrinous debris and/or desquamated mucosa
- Ascaris lumbricoides
- Clonorchis sinensis
- Fasciola hepatica
- Low-level echoes within the GB
- Cholesterol crystals (small but echogenic)
- Multiple small calculi
- Pus
- Abnormal mucous
- Parasites
- Milk calcium bile or limy bile (echogenicity intermediate between that of sludge and calculi)
- Concentration of bile
The concentration of bile in the fasting patient may give rise to sludge formation. This is slightly echogenic and does not cause shadowing, but it may form a bile/sludge level. The biochemical nature of sludge has been recognized to consist predominantly of aggregates of cholesterol crystals and liquid crystalline droplets. In some cases of obstructive jaundice and symptomatic liver disease, it is composed of bilirubin granules embedded in a gel matrix of mucous glycoproteins.
Biliary sludge is often associated with biliary stasis, as occurs in association with parenteral nutrition, fasting, pregnancy, and mucous hypersecretion (eg, mucin-secreting bile duct tumors). In most patients, the presence of sludge is a transient phenomenon; as the patient's condition improves, the sludge resolves. If the lumen of the GB is completely filled with sludge that has an echogenicity similar to that of the liver, the GB may not be seen; this process is called hepatization.
Causes of pericholecystic fluid may include the following6 :
- Acute cholecystitis
- Pericholecystic abscess
- Subacute GB perforation
- Gangrenous infarction of GB
- Ascites
- Pancreatitis
- Peptic ulcer, with or without perforation
- Liver abscess
- Peritonitis
- Ligamentum teres abscess
- Ruptured hepatic adenoma
- Ruptured ectopic gestation
- AIDS
- Low-level echoes in the adjacent liver (eg, secondary to inflammation of the hepatic flexure of colon)
The lack of findings associated with AC and a clinical picture not suggestive of acalculous cholecystitis should suggest the possibility of other causes of pericholecystic fluid.
Nuclear Imaging
Normal cholescintigrams. Normal technetium-99m hepatic iminodiacetic acid (99mTc-HIDA) scans of the liver shows normal gallbladder filling within 45 minutes.
Technetium-99m hepatic iminodiacetic acid (99mTc-HIDA) scan followed for 1 hour 30 minutes shows no filling of the gallbladder due to cystic duct obstruction.
Findings
Technetium-99m iminodiacetic acid (99m Tc-IDA) agents (disofenin and mebrofenin) are routinely used in the performance of cholescintigraphy (see Images 16-17). After the intravenous injection, these compounds are rapidly bound to plasma proteins and are transported to the liver. There, the IDA compounds dissociate from their protein binding. After dissociation, the compounds are taken up by the hepatocytes through a carrier-mediated non–sodium-dependent membrane transport mechanism. This is the same pathway as that of bilirubin. Therefore, when the serum bilirubin level increases, competition for the carrier molecules occurs, and biliary excretion of IDA compounds is diminished.29,30,31
Unlike bilirubin, IDA compounds do not undergo conjugation in the hepatocytes, and they are rapidly excreted into the bile. The compounds enable excellent visualization of the bile ducts and GB within 30-60 minutes. Because AC is initiated by cystic duct obstruction, nonvisualization of the GB after the intravenous injection of99m Tc-IDA is better correlated with acute cholecystitis (AC) than is the detection of gallstones. Normally, the gallbladder (GB) is visualized within 60 minutes after tracer injection. Visualization of the GB establishes cystic duct patency and excludes AC with only rare exceptions. Nonvisualization of the GB 3-4 hours after the injection because of cystic duct obstruction is characteristic of an AC.
Alternatively, morphine infusion may be used to shorten the examination time. Morphine increases tone in the sphincter of Oddi, increases CBD pressure, and results in a pressure differential between the CBD and the GB; this promotes tracer entry into the GB. Nonvisualization of the GB 30 minutes after the morphine infusion suggests AC cholecystitis in the appropriate clinical setting. The rim sign indicates inflammatory spread into the adjacent liver parenchyma; in cases of AC, this is usually a sign that GB gangrene has set in, with or without perforation.
In one study, radionuclide angiography and cholescintigraphy were performed with a bolus injection of99m Tc-disofenin in 65 patients with clinically suspected AC. AC was surgically confirmed in 23 of 25 patients who had positive radionuclide angiographic findings (a positive result was indicated by increased blood flow to the GB fossa). Severe AC and abscesses were present in 3 patients with a scintigraphically visible GB but with positive angiographic findings. All 20 patients for whom there were positive findings on radionuclide angiography and cholescintigraphy had transmural cholecystitis. Of the 9 patients with AC and false-negative angiographic findings, none had abscess or gangrene of the GB.
Radionuclide angiography may therefore allow the determination of AC severity. In one study, 9 of 25 patients with positive findings had gangrenous cholecystitis or a pericholecystic abscess. Positive findings on radionuclide angiograms may shorten the patient examination, and delayed images (>1 h) may not be necessary.
Gallium-67 (67 Ga) has been shown to accumulate in both inflammatory and infective processes. In one study of 10 patients with cholecystitis examined with67 Ga scanning, images in 5 patients with AC showed significant accumulation in the GB.
Degree of Confidence
Cholescintigraphy is highly sensitive in the diagnosis of acute cholecystitis (AC), and it is especially valuable when ultrasound results are equivocal. The negative predictive value of a normal cholescintigram is greater than 98%.32 The rim sign is not sensitive (35% sensitivity), but it is reasonably specific in cases of complicated cholecystitis; however, the specificity is not high enough to obviate delayed or postmorphine images.32
In a meta-analysis, cholescintigraphy displayed a sensitivity of 97% and a specificity of 90% for AC; by way of comparison, ultrasonography displayed a sensitivity of 91% and a specificity of 79%. Although cholescintigraphy is more accurate than ultrasonography, the latter has the advantages of allowing evaluation of all the abdominal structures (possibly enabling an alternative diagnosis for patients with right-upper-quadrant pain who do not have AC). In patients who do have AC, ultrasonography may provide anatomic information regarding gallbladder size, stone size, gallbladder wall thickness, and bile duct size.
Cholescintigraphy is less accurate in diagnosing acalculous AC than it is in diagnosing calculous AC. Sensitivities are 68-100%; specificities are 38-100%. Morphine administration may be particularly helpful in preventing false-positive results in patients with suspected acalculous AC. Use of cholecystokinin before the study causes the emptying of viscous bile from the gallbladder and helps prevent false-positive results.
Although67 Ga scanning is noninvasive, it has not found acceptance in the diagnosis of AC.
False Positives/Negatives
Spontaneous resolution of an acute cholecystitis (AC) may occur 5-7 days after onset of symptoms because of reestablishment of cystic duct patency. In such circumstances, the gallbladder (GB) may appear normal on cholescintigraphy. In a small number of patients with acalculous cholecystitis, GB visualization may be normal. Most patients with acute acalculous cholecystitis (AAC), however, have a functional cystic duct obstruction as a result of vasculitis or edema; in these cases, GB visualization is unusual. The presence of tracer in the duodenal cap, dilation of the cystic duct, or a duodenal diverticulum may be misinterpreted as GB filling. In appearance, chronic cholecystitis and AC may be indistinguishable. In only 4-8% of cases is the GB not visualized. Especially in patients with symptomatic, chronic cholecystitis is the GB not visualized.
False-positive results with hepatic iminodiacetic acid (HIDA) scanning (eg, lack of GB visualization) are possible in association with the following:
- Prolonged fasting (gallbladder full)
- Total parenteral nutrition
- Ingestion of food less than 1 hour before scanning
- Acute pancreatitis
- Hepatitis
- Alcoholism
- Cirrhosis
- Gallbladder hydrops
- Chronic cholecystitis
- Postpartum state (speculative)
- Hydatid cyst rupture into the biliary tree
Serial67 Ga scanning is needed to rule out gallium accumulation in the hepatic flexure of the colon, which is a potential cause of a false-positive result. The accumulation of67 Ga has also been reported in cases of chronic cholecystitis.
Angiography
Findings
Patients with acute cholecystitis (AC) are rarely examined with angiography. Historically, angiographic findings of AC have been described. Marked hypervascularity with dilatation of the cystic artery may be observed, but the inflammatory process also results in the acquisition of blood from the right hepatic arterial supply. Arterial blush is present in association with an increase in the accumulation of contrast material in the gallbladder, the GB fossa, and the associated inflammatory mass. In the subacute phase of disease, hypervascularity persists, but parenchymal accumulation of contrast material may occur early and may be prominent; in such cases, a thickened GB wall is apparent. GB veins are seldom seen when the GB is normal, but in the subacute stage of AC, the GB veins may be particularly prominent.
Degree of Confidence
Angiography has no role in the diagnosis of acute cholecystitis. Angiography is an invasive procedure, and there are risks associated with the use of contrast material; with radiation exposure; and with other factors.
False Positives/Negatives
Empyema of the GB may arise de novo or as a complication of acute cholecystitis; the angiographic findings may be similar to those seen in cases of subacute AC.
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References
Dahnert W. Radiology Review Manual. 6th edition. Philadelphia, Pa: Wolters Kluwer Health; 2006.
Claesson B, Holmlund D, Mätzsch T. Biliary microflora in acute cholecystitis and the clinical implications. Acta Chir Scand. 1984;150(3):229-37. [Medline].
Ahmad MM, Macon WL 4th. Gangrene of the gallbladder. Am Surg. Mar 1983;49(3):155-8. [Medline].
Teixeira JP, Malheiro L, Pontinha N, Friões F, da Fonseca F, Saleiro V. Infectious factors in acute acalculous cholecystitis. Hepatogastroenterology. Nov-Dec 2002;49(48):1484-6. [Medline].
Hashemzehi M, Esmaili-Motlagh M, Moodi M, Balali-Mood M. Narcotic drug abuse and other risk factors in 100 operated patients for acute cholecystitis in Birjand, Iran. Saudi Med J. May 2008;29(5):698-702. [Medline].
Bisset RA, Khan AN. Differential Diagnosis in Abdominal Ultrasound. London, England: WB Saunders Co; 2002:159-80.
Babb RR. Acute acalculous cholecystitis. A review. J Clin Gastroenterol. Oct 1992;15(3):238-41. [Medline].
Kimura Y, Takada T, Kawarada Y, Nimura Y, Hirata K, Sekimoto M. Definitions, pathophysiology, and epidemiology of acute cholangitis and cholecystitis: Tokyo Guidelines. J Hepatobiliary Pancreat Surg. 2007;14(1):15-26. [Medline].
Barakos JA, Ralls PW, Lapin SA, Johnson MB, Radin DR, Colletti PM. Cholelithiasis: evaluation with CT. Radiology. Feb 1987;162(2):415-8. [Medline].
Lim ST, Sohn MH. Rim sign in acute cholecystitis correlative images between hepatobiliary scintigraphy and helical computed tomography. Clin Nucl Med. Jan 2002;27(1):67-8. [Medline].
Chang CW, Liao WS, Shih SC, Lin SC, Wang TE, Chang WH, et al. Vomiting and a target sign on abdominal CT. Gut. May 2008;57(5):663, 694. [Medline].
Hakansson K, Leander P, Ekberg O, Hakansson HO. MR imaging in clinically suspected acute cholecystitis. A comparison with ultrasonography. Acta Radiol. Jul 2000;41(4):322-8. [Medline].
Regan F, Schaefer DC, Smith DP, et al. The diagnostic utility of HASTE MRI in the evaluation of acute cholecystitis. Half-Fourier acquisition single-shot turbo SE. J Comput Assist Tomogr. Jul-Aug 1998;22(4):638-42. [Medline].
Petroianu A, Alberti LR. Importance of the new radiographic sign of fecal loading in the cecum in the presence of acute appendicitis in comparison with other inflammatory diseases of the right abdomen. Eur J Intern Med. Jan 2008;19(1):22-6. [Medline].
Berk RN. Oral Cholecystography. In: Berk RN, Ferrucci JT and Leopold GR. Radiology of the Gallbladder and Bile Ducts: Diagnosis and Intervention. First Ed. Philadelphia, Pa: WB Saunders Co; 1983:83-162.
Jhaveri KS, Harisinghani MG, Wittenberg J. Right-sided colonic diverticulitis: CT findings. J Comput Assist Tomogr. Jan-Feb 2002;26(1):84-9. [Medline].
Paulson EK. Acute cholecystitis: CT findings. Semin Ultrasound CT MR. Feb 2000;21(1):56-63. [Medline].
Loud PA, Semelka RC, Kettritz U, et al. MRI of acute cholecystitis: comparison with the normal gallbladder and other entities. Magn Reson Imaging. 1996;14(4):349-55. [Medline].
Park MS, Yu JS, Kim YH, et al. Acute cholecystitis: comparison of MR cholangiography and US. Radiology. Dec 1998;209(3):781-5. [Medline].
Pu Y, Yamamoto F, Igimi H, et al. A comparative study usefulness of magnetic resonance imaging in the diagnosis of acute cholecystitis. J Gastroenterol. Apr 1994;29(2):192-8. [Medline].
Bilgin M, Balci NC, Erdogan A, Momtahen AJ, Alkaade S, Rau WS. Hepatobiliary and pancreatic MRI and MRCP findings in patients with HIV infection. AJR Am J Roentgenol. Jul 2008;191(1):228-32. [Medline].
Oto A, Ernst RD, Ghulmiyyah LM, Nishino TK, Hughes D, Chaljub G, et al. MR imaging in the triage of pregnant patients with acute abdominal and pelvic pain. Abdom Imaging. Mar 11 2008;[Medline].
Draghi F, Ferrozzi G, Calliada F, et al. Power Doppler ultrasound of gallbladder wall vascularization in inflammation: clinical implications. Eur Radiol. 2000;10(10):1587-90. [Medline].
Famulari C, Macri A, Galipo S, et al. The role of ultrasonographic percutaneous cholecystostomy in treatment of acute cholecystitis. Hepatogastroenterology. May-Jun 1996;43(9):538-41. [Medline].
Schiller VL, Turner RR, Sarti DA. Color doppler imaging of the gallbladder wall in acute cholecystitis: sonographic-pathologic correlation. Abdom Imaging. May-Jun 1996;21(3):233-7. [Medline].
Uggowitzer M, Kugler C, Schramayer G, et al. Sonography of acute cholecystitis: comparison of color and power Doppler sonography in detecting a hypervascularized gallbladder wall. AJR Am J Roentgenol. Mar 1997;168(3):707-12. [Medline].
Eiberg JP, Grantcharov TP, Eriksen JR, Boel T, Buhl C, Jensen D, et al. Ultrasound of the acute abdomen performed by surgeons in training. Minerva Chir. Feb 2008;63(1):17-22. [Medline].
Rosen CL, Brown DF, Chang Y, Moore C, Averill NJ, Arkoff LJ. Ultrasonography by emergency physicians in patients with suspected cholecystitis. Am J Emerg Med. Jan 2001;19(1):32-6. [Medline].
Lin EC, Kuni CC. Radionuclide imaging of hepatic and biliary disease. Semin Liver Dis. May 2001;21(2):179-94. [Medline].
Lin EC, Kuni CC. Radionuclide imaging of hepatic and biliary disease. Semin Liver Dis. May 2001;21(2):179-94. [Medline].
Waxman AD, Siemsen JK. Gallium gallbladder scanning in cholecystitis. J Nucl Med. Feb 1975;16(2):148-50. [Medline].
Kalimi R, Gecelter GR, Caplin D, Brickman M, Tronco GT, Love C. Diagnosis of acute cholecystitis: sensitivity of sonography, cholescintigraphy, and combined sonography-cholescintigraphy. J Am Coll Surg. Dec 2001;193(6):609-13. [Medline].
Chopra S, Dodd GD 3rd, Mumbower AL, et al. Treatment of acute cholecystitis in non-critically ill patients at high surgical risk: comparison of clinical outcomes after gallbladder aspiration and after percutaneous cholecystostomy. AJR Am J Roentgenol. Apr 2001;176(4):1025-31. [Medline].
Seow VK, Lin CM, Wang TL, Chong CF, Lin IY. Acute emphysematous cholecystitis with initial normal radiological evaluation: a fatal diagnostic pitfall in the ED. Am J Emerg Med. May 2007;25(4):488.e3-488.e5. [Medline].
Husain EA, Prescott RJ, Haider SA, Al-Mahmoud RW, Zelger BG, Zelger B, et al. Gallbladder Sarcoma: A Clinicopathological Study of Seven Cases from the UK and Austria with Emphasis on Morphological Subtypes. Dig Dis Sci. Jul 10 2008;[Medline].
Adam A, Roddie ME. Acute cholecystitis: radiological management. Baillieres Clin Gastroenterol. Dec 1991;5(4):787-816. [Medline].
Avrahami R, Badani E, Watemberg S, et al. The role of percutaneous transhepatic cholecystostomy in the management of acute cholecystitis in high-risk patients. Int Surg. Apr-Jun 1995;80(2):111-4. [Medline].
Bigio EH, Haque AK. Disseminated cytomegalovirus infection presenting with acalculous cholecystitis and acute pancreatitis. Arch Pathol Lab Med. Nov 1989;113(11):1287-9. [Medline].
Boland GW, Lee MJ, Dawson SL, Mueller PR. Percutaneous cholecystostomy for acute acalculous cholecystitis in a critically ill patient. AJR Am J Roentgenol. Apr 1993;160(4):871-4. [Medline].
Boland GW, Lee MJ, Leung J, Mueller PR. Percutaneous cholecystostomy in critically ill patients: early response and final outcome in 82 patients. AJR Am J Roentgenol. Aug 1994;163(2):339-42. [Medline].
Bortoff GA, Chen MY, Ott DJ, et al. Gallbladder stones: imaging and intervention. Radiographics. May-Jun 2000;20(3):751-66. [Medline].
Bree RL, Ralls PW, Balfe DM, et al. Evaluation of patients with acute right upper quadrant pain. American College of Radiology. ACR Appropriateness Criteria. Radiology. Jun 2000;215 Suppl:153-7. [Medline].
Browning PD, McGahan JP, Gerscovich EO. Percutaneous cholecystostomy for suspected acute cholecystitis in the hospitalized patient. J Vasc Interv Radiol. Jul-Aug 1993;4(4):531-7; discussion 537-8. [Medline].
Dequanter D, Lefebvre JC, Takieddine M, et al. [An acute pseudo-cholecystitis]. Rev Med Brux. Oct 2001;22(5):439-41. [Medline].
England RE, McDermott VG, Smith TP, et al. Percutaneous cholecystostomy: who responds?. AJR Am J Roentgenol. May 1997;168(5):1247-51. [Medline].
Fraser AG, Ali MR, McCullough S, et al. Diagnostic tests for Helicobacter pylori--can they help select patients for endoscopy?. N Z Med J. Mar 22 1996;109(1018):95-8. [Medline].
Ghahreman A, McCall JL, Windsor JA. Cholecystostomy: a review of recent experience. Aust N Z J Surg. Dec 1999;69(12):837-40. [Medline].
Gruber PJ, Silverman RA, Gottesfeld S, Flaster E. Presence of fever and leukocytosis in acute cholecystitis. Ann Emerg Med. Sep 1996;28(3):273-7. [Medline].
Guarner J, Shieh WJ, Morgan J, et al. Leptospirosis mimicking acute cholecystitis among athletes participating in a triathlon. Hum Pathol. Jul 2001;32(7):750-2. [Medline].
Hatzidakis AA, Prassopoulos P, Petinarakis I, et al. Acute cholecystitis in high-risk patients: percutaneous cholecystostomy vs conservative treatment. Eur Radiol. Jul 2002;12(7):1778-84. [Medline].
Hultman CS, Herbst CA, McCall JM, Mauro MA. The efficacy of percutaneous cholecystostomy in critically ill patients. Am Surg. Apr 1996;62(4):263-9. [Medline].
Imamoglu M, Sarihan H, Sari A, Ahmetoglu A. Acute acalculous cholecystitis in children: Diagnosis and treatment. J Pediatr Surg. Jan 2002;37(1):36-9. [Medline].
Kiviniemi H, Makela JT, Autio R, et al. Percutaneous cholecystostomy in acute cholecystitis in high-risk patients: an analysis of 69 patients. Int Surg. Oct-Dec 1998;83(4):299-302. [Medline].
Konno K, Ishida H, Naganuma H, et al. Emphysematous cholecystitis: sonographic findings. Abdom Imaging. Mar-Apr 2002;27(2):191-5. [Medline].
LaBerge JM, Gordon RL, Kerlan RK Jr, Ring EJ. Delayed gallbladder rupture following percutaneous cholecystostomy. J Vasc Interv Radiol. Nov 1991;2(4):539-41. [Medline].
Lee MJ, Saini S, Brink JA, et al. Treatment of critically ill patients with sepsis of unknown cause: value of percutaneous cholecystostomy. AJR Am J Roentgenol. Jun 1991;156(6):1163-6. [Medline].
Lo LD, Vogelzang RL, Braun MA, Nemcek AA Jr. Percutaneous cholecystostomy for the diagnosis and treatment of acute calculous and acalculous cholecystitis. J Vasc Interv Radiol. Jul-Aug 1995;6(4):629-34. [Medline].
McLoughlin RF, Patterson EJ, Mathieson JR, et al. Radiologically guided percutaneous cholecystostomy for acute cholecystitis: long-term outcome in 50 patients. Can Assoc Radiol J. Dec 1994;45(6):455-9. [Medline].
Merriam LT, Kanaan SA, Dawes LG, Angelos P, Prystowsky JB, Rege RV. Gangrenous cholecystitis: analysis of risk factors and experience with laparoscopic cholecystectomy. Surgery. Oct 1999;126(4):680-5; discussion 685-6. [Medline].
Muttarak M, Na Chiangmai W. Clinics in diagnostic imaging (62). Gallstones with acute cholecystitis. Singapore Med J. Jun 2001;42(6):280-5. [Medline].
Patel M, Miedema BW, James MA, Marshall JB. Percutaneous cholecystostomy is an effective treatment for high-risk patients with acute cholecystitis. Am Surg. Jan 2000;66(1):33-7. [Medline].
Shin SJ, Na KS, Jung SS, et al. Acute acalculous cholecystitis associated with systemic lupus erythematosus with Sjogren''s syndrome. Korean J Intern Med. Mar 2002;17(1):61-4. [Medline].
Shirai Y, Tsukada K, Kawaguchi H, et al. Percutaneous transhepatic cholecystostomy for acute acalculous cholecystitis. Br J Surg. Nov 1993;80(11):1440-2. [Medline].
Spain DA, Bibbo C, Ecker T, et al. Operative tube versus percutaneous cholecystostomy for acute cholecystitis. Am J Surg. Jul 1993;166(1):28-31. [Medline].
Spira RM, Nissan A, Zamir O, et al. Percutaneous transhepatic cholecystostomy and delayed laparoscopic cholecystectomy in critically ill patients with acute calculus cholecystitis. Am J Surg. Jan 2002;183(1):62-6. [Medline].
Teplick SK, Harshfield DL, Brandon JC, et al. Percutaneous cholecystostomy in critically ill patients. Gastrointest Radiol. Spring 1991;16(2):154-6. [Medline].
Van Steenbergen W, Ponette E, Marchal G, et al. Percutaneous transhepatic cholecystostomy for acute complicated cholecystitis in elderly patients. Am J Gastroenterol. Oct 1990;85(10):1363-9. [Medline].
Van Steenbergen W, Rigauts H, Ponette E, et al. Percutaneous transhepatic cholecystostomy for acute complicated calculous cholecystitis in elderly patients. J Am Geriatr Soc. Feb 1993;41(2):157-62. [Medline].
vanSonnenberg E, D''Agostino HB, Goodacre BW, et al. Percutaneous gallbladder puncture and cholecystostomy: results, complications, and caveats for safety. Radiology. Apr 1992;183(1):167-70. [Medline].
Vauthey JN, Lerut J, Martini M, et al. Indications and limitations of percutaneous cholecystostomy for acute cholecystitis. Surg Gynecol Obstet. Jan 1993;176(1):49-54. [Medline].
Vingan HL, Wohlgemuth SD, Bell JS 3rd. Percutaneous cholecystostomy drainage for the treatment of acute emphysematous cholecystitis. AJR Am J Roentgenol. Nov 1990;155(5):1013-4. [Medline].
Zeebregts CJ, Wijffels RT, de Jong KP, et al. Percutaneous drainage of emphysematous cholecystitis associated with pneumoperitoneum. Hepatogastroenterology. Mar-Apr 1999;46(26):771-4. [Medline].
Further Reading
Guidelines and clinical studies:
Treatment of gallstone and gallbladder disease. Society for Surgery of the Alimentary Tract, Inc - Medical Specialty Society. 1996 (revised 2003 Feb 1). 4 pages. NGC:003756
Harmonic in Laparoscopic Cholecystectomy for Acute Cholecystitis
Acute Cholecystitis – Early Laparoscopic Surgery Versus Antibiotic Therapy and Delayed Elective Cholecystectomy
FDG-PET/CT in the Evaluation of Patients With Suspected Cholecystitis
The Role of Antibiotic Treatment in Patients With Acute Mild Cholecystitis - A Prospective Randomized Controlled Trial
Keywords
acute cholecystitis, acute acalculous cholecystitis, acalculous cholecystitis, AC, AAC, necrotizing cholecystitis, emphysematous cholecystitis


































Imaging: Cholecystitis, Acute