Acute Cholecystitis

Acute cholecystitis results from obstruction of the gallbladder neck or cystic duct by a gallstone in 80% to 95% of patients.34 Acute acalculous cholecystitis (AAC) composes 5% to 15% of cases of acute cholecystitis and is typically caused by diminished gallbladder emptying (eg, in patients with severe trauma/surgery, burns, shock, anesthesia, diabetes); by decreased blood flow in the cystic artery because of obstruction, hypotension, or embolization; or by bacterial infection.35,36 Although most patients present with typical right upper quadrant symptoms, this diagnosis may be challenging in patients with complicated systemic disease and sepsis.

Patients with suspected cholecystitis should be imaged for 2 major reasons. First, most patients (60%-85%) referred to exclude cholecystitis have other causes of right upper quadrant pain, including peptic ulcer disease, pancreatitis, hepatitis, appendicitis, hepatic congestion from right-sided heart failure, perihepatitis from pelvic inflammatory disease (Fitz-Hugh-Curtis syndrome), right lower lobe pneumonia, right-sided pyelonephritis, or nephroureterolithiasis. If the patient does not have acute cholecystitis, the clinical workup can be redirected before the patient's clinical condition deteriorates. Secondly, imaging can diagnose severe complications such as emphy-sematous cholecystitis and perforation, which require immediate surgery.37

Patients with suspected acute cholecystitis should be evaluated with ultrasonography as the initial imaging procedure. If the diagnosis is in doubt, it can be confirmed with hepatobiliary scintigraphy or CT. Multidetector CT is often initially performed in many cases because the diagnosis is unclear. CT is also helpful in suspected complications of acute cholecystitis, such as emphysematous cholecystitis or gallbladder perforation. MRI is usually used to exclude obstructing and nonobstructing biliary tract stones.

The morphologic changes that occur in acute cholecystitis are well depicted in imaging studies and result from the presence of stones, increased mural blood flow, and capillary leakage caused by inflammatory changes, mural thickening of the gallbladder, and pericholecystic fluid.

Sonographic Findings

The sonographic findings of acute uncomplicated cholecystitis include gallstones often impacted in the cystic duct or gallbladder neck (Fig. 6), mural thickening (>3 mm), a 3-layered appearance of the gallbladder wall, hazy delineation of the gallbladder, localized pain with maximal tenderness elicited over the gallbladder (sonographic Murphy's sign), pericholecystic fluid, and gallbladder distension.38,39 Gallstones and the sonographic Murphy's sign are the most specific indicators of acute cholecystitis with a positive predictive value of 92%.38,39 The sonographic Murphy's sign may be difficult to elicit in obtunded patients and those who have received pain medication. The sign may be absent in patients with gangrenous cholecystitis. Finding an impacted stone in the cystic duct or gallbladder neck also increases the likelihood of acute cholecystitis.38-42

Multidetector CT Findings

The CT findings (Fig. 7) of acute cholecystitis have been well described and include gallstones, mural thickening of the gallbladder, mural edema, pericholecystic fluid and inflammation, and transient increased enhancement of the liver parenchyma adjacent to the gallbladder caused by hyperemia.1,2,4,17 CT is less sensitive (75%) than ultrasonography in the depiction of gallstones. Stones with significant calcification or the presence of gas in a noncalcified stone (the Mercedes-Benz sign) are best seen with CT.17 The CT findings of acute cholecystitis have been divided into major and minor criteria. Major findings include calculi, mural thickening of the gallbladder, pericholecystic fluid, and subserosal edema. Minor findings are gallbladder distension and sludge. The overall sensitivity, specificity, and accuracy of CT for the diagnosis of acute cholecystitis are 91.7%, 99.1%, and 94.3%, respectively.41-45

MRI Findings

MRI (Fig. 8) rivals ultrasonography and CT in the depiction of acute cholecystitis. On postgadolinium T1-weighted images, acute cholecystitis manifests as increased mural enhancement, mural thickening, and transient increased enhancement of the adjacent liver parenchyma. Findings on T2-weighted images include the presence of gallstones, the presence of an intramural abscess appearing as a hyperintense

Cholecystitis Patient
Fig. 6. Acute cholecystitis: sonographic findings. Longitudinal (A) and transverse (B) sonograms show a large obstructing stone (open arrow) within the gallbladder neck associated with a thick, hypoechoic gallbladder wall (arrows). The patient also had a sonographic Murphy sign.
CholcytitisGallbladder Findings

Fig. 7. Acute cholecystitis: CT findings. (A) Multiple calcified stones (open arrow) are seen in the dependent portion of the gallbladder. Mural thickening (solid arrows) of the gallbladder is also present. (B) In a different patient, the inflamed gallbladder (open arrow) is causing hyperenhancement of the adjacent liver (solid arrows).

focus in the gallbladder wall, and increased wall thickness. Periportal edema depicted as periportal high signal intensity may be observed but is a nonspecific finding.46-48

Hepatobiliary Scintigraphy

Radionuclide cholescintigraphy with technetium Tc 99m-labelled iminodiacetic acid analogs (hepatobiliary iminodiacetic acid scan) was first introduced in the late 1970s. In this study, hepatic parenchymal uptake is observed within 1 minute, with peak activity occurring at 10 to 15 minutes. The bile ducts are usually visualized within 10 minutes, and the gallbladder should fill with isotope within 1 hour if the cystic duct is patent. If the gallbladder is not identified, delayed imaging up to 4 hours should be performed.1-3 Prompt biliary excretion of the isotope without visualization of the gallbladder is the hallmark of acute cholecystitis (Fig. 9).

False-positive results may occur in patients with abnormal bile flow because of hepatic parenchymal disease or a prolonged fast with a distended, sludge-filled gallbladder. Delayed gallbladder filling can be seen in the setting of chronic cholecystitis.1

Cholecystitis Mri

Fig. 8. Acute cholecystitis: MRI findings. (A) Axial fat-suppressed T2-weighted image shows a gallstone (arrowhead), mural thickening (solid arrows) of the gallbladder and high signal intensity pericholecystic fluid (open arrow). (B) Coronal MRCP image shows gallstones (arrowhead) and a large amount of subhepatic, pericholecystic fluid (open arrows) in a more severe case of acute cholecystitis.

Fig. 8. Acute cholecystitis: MRI findings. (A) Axial fat-suppressed T2-weighted image shows a gallstone (arrowhead), mural thickening (solid arrows) of the gallbladder and high signal intensity pericholecystic fluid (open arrow). (B) Coronal MRCP image shows gallstones (arrowhead) and a large amount of subhepatic, pericholecystic fluid (open arrows) in a more severe case of acute cholecystitis.

Fig. 9. Acute cholecystitis: hepatobiliary scintigraphy findings. A 60-minute image from a heptobiliary scintiscan shows isotope in the duodenum and small bowel (solid arrows) but none in the gallbladder (open arrow).

Get Rid of Gallstones Naturally

Get Rid of Gallstones Naturally

One of the main home remedies that you need to follow to prevent gallstones is a healthy lifestyle. You need to maintain a healthy body weight to prevent gallstones. The following are the best home remedies that will help you to treat and prevent gallstones.

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