Importance of 1H-MR spectroscopy of the brain to identify the minimal hepatic encephalopathy in different patients with liver cirrhosis: A prospective study

Abstract

Objectives: Liver cirrhosis patients commonly progress to minimal hepatic encephalopathy (MHE) with cognitive impairment and raised blood ammonia and proinflammatory cytokines levels. This study aims to identify the subjects of MHE in patients with liver cirrhosis by hydrogen 1 magnetic resonance (1H-MR) spectroscopy of the brain, serum proinflammatory cytokines, and neuropsychiatric tests. Materials and Methods: This prospective was carried out on 100 patients of liver cirrhosis without overt hepatic encephalopathy (HE) and compared with 100 healthy controls in a tertiary care hospital in Northeast India between September 2017 and October 2019. The psychometric hepatic encephalopathy score (PHES) neuropsychological tests, cranial MRIwith 1H-MR spectroscopy, and estimation of serum interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were done. The PHES scores and serum proinflammatory markers levels were correlated with the conventional and 1H-MR spectroscopy findings of the brain. Results: The mean PHES score in the case group was −7.58±3.43 (standard deviation [SD]) and the control group was −3.41 ± 3.87 (SD). Patients with Child-Pugh class A (n = 8) had a PHES score of −8.7 ± 2.5 (SD), class B (n = 42) −7.62 ± 3.7 (SD), and class C (n = 50) had a score of −7.36 ± 3.3 (SD). The mean value of IL-6 and TNF-α in the case group was 219 ± 180 (SD) pg/mL and 99 ± 118 (SD) pg/mL and the control group was 67.4 ± 77 (SD) pg/mL and 57.5 ± 76 (SD) pg/mL. Globus pallidus T1-weighted hyperintensities on the visibility scale with a visibility score of 0 were observed in 39 cases, a score of 1 in 38 cases, and a score of 2 in 23 cases. Increased glutamate/glutamine/creatine (Glx/Cr) ratio was identified in the case group on MR spectroscopy as compared to the control (0.95 ± 0.24 vs. 0.31 ± 0.19, P < 0.0005), a decrease of myoinositol/creatine (mI/Cr) ratio (0.11 ± 0.13 vs. 0.30 ± 0.12, P < 0.0005), and increase choline/creatine (Cho/Cr) ratio (0.69 ± 0.26 vs. 0.61 ± 0.20, P < 0.0005). There was a statistically significant difference in Glx/Cr, mI/Cr and Cho/Cr ratio between the case and control groups with P < 0.0005. Conclusion: Predicting the development of MHE in established cases of liver cirrhosis using non-invasive modalities like PHES, IL-6, TNF-α levels, and 1H-MR spectroscopy plays an important role in further progression to overt HE and coma.