Critical flicker frequency is diagnostic of minimal hepatic encephalopathy
Serag Esmat1, Nouman El Garem1, Hassan Raslan2
1Department of Internal Medicine, Cairo University, Cairo, Egypt.
Abstract:
Minimal hepatic encephalopathy may affect up to 80% of cirrhotic patients, in the absence of overt hepatic encephalopathy. The objective of the study is to evaluate the accuracy of diagnosis of minimal hepatic encephalopathy with critical flicker frequency (CFF). The study was conducted on 180 patients with post hepatitis C liver cirrhosis and on 60 healthy subjects as control. Patients and controls were divided into four groups: group 1 (60), healthy individuals as a control group; group 2 (60), patients with liver cirrhosis (Child class A); group 3 (60), patients with liver cirrhosis (Child class B); and group 4 (60), patients with liver cirrhosis (Child class C). All participants were subjected to estimation of CFF, line drawing test, complete blood picture, liver functions, viral markers, and abdominal ultrasound. CFF detected abnormality in 90% of patients. Accuracy of CFF in differentiation of Child A from normal is 100%, Child B from normal is 100%, Child C from normal is 100%, Child A from Child B is 80%, Child A from Child C is 100% and Child B from Child C is 100%, and it has higher accuracy than line drawing test. CFF is a simple, reliable and accurate method for the diagnosis of minimal hepatic encephalopathy. It is not influenced by the patient level of education.
Insights
Critical flicker frequency (CFF) accurately diagnoses minimal hepatic encephalopathy in liver cirrhosis patients. This simple test shows high accuracy, outperforming the line drawing test for diagnosing this condition.
Area of Science:
- Hepatology
- Neurology
- Diagnostic Medicine
Background:
- Minimal hepatic encephalopathy affects up to 80% of patients with liver cirrhosis.
- Diagnosis is challenging in the absence of overt symptoms.
Purpose of the Study:
- To evaluate the diagnostic accuracy of critical flicker frequency (CFF) for minimal hepatic encephalopathy.
- To compare CFF's accuracy against the line drawing test.
Main Methods:
- A study involving 180 patients with post-hepatitis C liver cirrhosis and 60 healthy controls.
- Participants were categorized into four groups based on Child class (A, B, C) and health status.
- Assessments included CFF, line drawing test, blood tests, liver function tests, viral markers, and ultrasound.
Main Results:
- CFF detected abnormalities in 90% of patients with liver cirrhosis.
- CFF demonstrated high diagnostic accuracy across all comparisons (e.g., 100% for Child A vs. normal).
- CFF showed superior accuracy compared to the line drawing test.
Conclusions:
- Critical flicker frequency is a simple, reliable, and accurate method for diagnosing minimal hepatic encephalopathy.
- CFF is unaffected by a patient's educational background.
- CFF offers a valuable tool for identifying minimal hepatic encephalopathy in cirrhotic patients.
