Classically, the onset of head tremor in essential tremor (ET) patients follows that of hand tremor, such that there is a somatotopic spread of involved areas. Here we present a series of seven self-reportedly "unaffected" relatives of ET cases. These seven were clinically asymptomatic and had normal levels of arm tremor on examination, yet each evidenced a transient head wobble on examination. We estimate the prevalence of this phenotype within the two studies from which cases were ascertained.ET cases and their self-reportedly affected and unaffected relatives, enrolled in two family studies, underwent a medical history and videotaped neurological examination.In seven self-reportedly "unaffected" relatives, a transient and subtle head wobble was seen, always during sustained phonation, speech, or reading aloud. Total tremor score (a measure of arm tremor) ranged from 5 to 12 (i.e., mild tremor within the range of normal). The prevalence of this phenotype of early head tremor was 3.7

作者：Elan D, Louis；Funmi M, Badejo；Ashley D, Cristal；James, Meyers；Nora, Hernandez；Karen P, Chen；Kelly V, Naranjo；Jemin, Park；Lorraine N, Clark

来源：Tremor and other hyperkinetic movements (New York, N.Y.) 2017 年 7卷