Magnetic resonance relaxometry reveals central pontine abnormalities in clinically asymptomatic alcoholic men

Background: Central pontine myelinolysis (CPM) is a rare, debilitating, lif e -threatening condition, associated with chronic alcoholism, rapid correct ion of hyponatremia, and advanced age. It is unknown, however, whether olde r alcoholic patients who by age and diagnosis are at risk for CPM have obje ctively determined neuroimaging evidence of preclinical CPM that could be v aluable in understanding its development and in initiating appropriate trea tment. Accordingly, we examined central pontine magnetic resonance (MR) tra nsverse relaxation time (T2), which reflects myelin and axonal integrity wh en measured in white matter and is prolonged with pathology that causes inc reased free water content in tissue. Methods: The subjects were 46 alcoholic men who were abstinent from alcohol for about I month and were asymptomatic for CPM, 9 men and I woman with al coholic Korsakoffs syndrome (KS), and 74 healthy control men. All subjects received coronally acquired dual-echo MR imaging (MRI), from which T2 times were calculated in central pons. MRI films were read clinically and indepe ndently of relaxometry results. Hematological and neuropsychological data w ere also available for many subjects. Results: Only the KS group showed prolonged T2 times; however, pontine T2 p rolongation increased significantly with older age in the asymptomatic alco holics but not controls. Clinical radiological readings detected pontine si gnal hyperintensity in five KS subjects (two without dementia and three wit h dementia), one control, and no alcoholic patient. Hematologic indexes of macrocytic anemia and nutritional deficiency and neuropsychological measure s of verbal and nonverbal fluency correlated with prolonged T2 times in alc oholic men. Conclusions: This CPM-like condition, manifest as prolonged T2, may occur w ith higher incidence than previously thought in clinically asymptomatic alc oholism and may contribute to neuropsychological compromise of initiation a nd production. Preclinical detection of abnormal pontine signal properties with MR relaxometry may identify patients at high risk for developing CPM.