Abstract
Mitochondrial encephalomyopathies include various symptoms such as central nervous system damage, muscle strength loss and diabetes. Leigh syndrome, which primarily affects children, is one of the mitochondrial encephalomyopathies classified on the basis of presenting clinical conditions and laboratory findings. In this study, we report the association between evoked potentials and clinical conditions in Leigh syndrome patients. The study subjects included five patients diagnosed as having Leigh syndrome. We recorded the short-latency somatosensory evoked potential, auditory brainstem response and visual evoked potential of all the patients. All the patients aged <1 year showed early symptoms of poor sucking or eye nystagmus; with time, all the patients regressed, but their symptoms worsened. We found no specific abnormality pattern for any patient by comparing the evoked potentials and clinical conditions. However, the patients with N20 and N30 scalp waves showed relatively better early clinical manifestation than those who lost scalp waves owing to gradual disease progression after regression. This observation can be attributed to the functions of the primary sensor area of N20 origin, basal ganglia of N30 origin, or early development of the subcortical pathway. The cumulative findings may indicate an association between the existence of scalp waves and early clinical manifestations. Thus, the scalp wave may be used as a reference indicator for predicting Leigh syndrome prognosis.
