EYE-Mobile TRACKer IN the Diagnosis of Minimal Hepatic Encephalopathy
Hepatic encephalopathy (HE) corresponds to the neurological or the neuropsychological symptoms caused by an acute or chronic liver disease and/or porto-systemic shunt. Many patients present neurological symptoms even if their liver disease is stabilized. Furthermore, HE is associated with an altered quality of life and an increased mortality. Its incidence is high with 30 to 80% of cirrhotic patients that will display according to retained diagnostic criteria. HE symptoms are going from subtle neuropsychological abnormalities detected only on neuropsychological testing, minimal HE, to altered consciousness, overt HE. Recently, the therapeutic armamentarium has increased with now several drugs (rifaximin, ammonia lowering agents) that are able to prevent new bouts of HE. Unfortunately, the diagnosis of minimal HE is difficult and no gold-standard is available. None of the proposed test is rapid and easily performed at bedside. Recently, different studies suggest the potential interest of the study of the ocular movements in HE. Abnormalities in ocular saccades could be an early predictor of cortical impairment. In a pilot feasibility study using an eye-tracker, we could show that cirrhotic patients with minimal HE had, compared to healthy controls, increased latencies, decreased speed of voluntary and reflex saccades, more errors in anti-saccades, more anticipations saccades and more difficulties to fix the target. Our hypothesis was that the use of the eye-tracker will enable the diagnosis of minimal HE by studying the characteristics of saccades and anti-saccades. Since no gold-standard is available for the diagnosis of minimal HE, we will use the conclusion of an adjudication committee formed by 2 experts. Their clinical judgment will take into account the results of medical history, clinical examination, neuropsychological testing, PHES, Critical Flicker Frequency test (CFF), ammonemia levels, EEG and brain MRI with spectroscopy.
Start: January 2021