Researchers have identified that multiple CT findings can identify patients with high-risk non-alcoholic fatty liver disease (NAFLD) — advanced fibrosis or cirrhosis, that is — though the presence of non-alcoholic steatohepatitis (NASH) remains elusive on CT.
Fibrosis, also known as fibrotic scarring, is a pathological wound healing in which connective tissue replaces normal parenchymal tissue to the extent that it goes unchecked, leading to considerable tissue remodeling and the formation of permanent scar tissue.
And, cirrhosis is a late stage of scarring (fibrosis) of the liver caused by many forms of liver diseases and conditions, such as hepatitis and chronic alcoholism.
“Subjective assessment of multiple morphologic and separately quantified parameters by trained readers and a simple quantitative three-parameter model combining two CT features, liver surface nodularity (LSN) and liver segmental volume ratio (LSVR), and a clinical score (FIB-4) showed good association with the presence of advanced fibrosis,” said researcher Meghan G. Lubner from the University of Wisconsin in the US.
For the study, the research team included a total of 186 patients with NAFLD (mean age, 49 years; 74 men and 112 women), of whom 87 (47 percent) had nonalcoholic steatohepatitis (NASH) and 112 (60 percent) had moderate to severe steatosis.
An experienced gastrointestinal pathologist performed a histopathologic review to determine steatosis, inflammation, and fibrosis.
The presence of any lobular inflammation and hepatocyte ballooning was categorized as nonalcoholic steatohepatitis (NASH), while patients with NAFLD and advanced fibrosis (stage F3 or higher) were categorized as having high-risk NAFLD. Two readers subjectively assessed the presence of NASH and fibrosis.
The researchers found that a total of 51 patients were classified as fibrosis stage F0, 42 as F1, 23 as F2, 37 as F3, and 33 as F4.
Additionally, 70 (38 percent) had advanced fibrosis (stage F3 or F4) and were considered to have high-risk NAFLD. FIB-4 score showed a correlation with fibrosis, and of the individual CT parameters, LSVR and splenic volume had the best performance. Meanwhile, subjective reader assessment performed best among all parameters. FIB-4 and subjective scores were complementary, and for NASH assessment, FIB-4 performed best.
Noting the well-established utility of CT in identifying hepatic steatosis, the authors of this AJR article concluded that CT can also be “a highly accessible, frequently used method for assessment of patients with NAFLD and identification of those with high-risk NAFLD (advanced fibrosis or cirrhosis) who are potentially most in need of intervention,” the researcher said.