Correlation of Cognitive Function and Proton Magnetic Resonance Spectroscopic(1H MRS) Findings in Subclinical Hepatic Encephalopathy / 신경정신의학

ABSTRACT

OBJECTIVES: To investigate the relationship of neurochemical changes of brain in SCHE patients and the level of cognitive function, the authors measured hydrogen containing neurochemicals in two brain regions using 1H MRS, and compared those changes with the level of cognitive performances such as attention, visual analysis, or fine motor function. METHODS: A total of patients with liver cirrohosis were defined as SCHE, for they performed poorly(out of 1 SD of normative data) in more than one neuropsychological tests conventionally used(digit symbol and block design tests in KWIS, trail making test A and B). They were further evaluated in attentional ability and efficacy of visual analysis using Cognitrone subtest in Vienna Neurocognitive Test battery. Fine motor coordination were also measured by Grooved Pegboard test. Patients and 20 normal controls underwent proton MRS study. Proton containing neurochemicals, such as myoinositol(mI), N-acetyl-L-aspartate(NAA), creatine(Cr), choline(Cho) were measured from 2*2*2cm3 voxel of basal ganglia and parietal white matter using 1.5 tesla clinical MRI/MRS system. The ratios of above metabolites to Cr were analyzed. RESULTS: 1) Patients with SCHE showed reductions in Cho/Cr and mI/Cr in both basal ganglia and parietal white matter compared to normal subjects. 2) Performance of Grooved Pegboard test were negatively correlated with mI level of basal ganglia and with Cho level of parietal white matter(r=-0.59, p<.05). 3) Mean time of correct responses in Cognitrone test showed negative correlation with NAA level of parietal white matter(r=-0.55, p<.05). CONCLUSION: Certain neurocognitive disturbances in SCHE patients seemed to be related with neurochemical changes in basal ganglia or parietal white matter. To further elucidate the relationship of focal biochemical changes and neurocognitive deficits in SCHE patients, however, follow-up study according to the illness stage must be performed. Studies on other disorders showing similar cognitive deficit patterns would be helpful.