Cone Dysfunction in a Subgroup of Patients With Autosomal Dominant Cerebellar Ataxia

Retinal Degeneration in the nervous Mutant Mouse. III. Electrophysiological Studies of the Visual Pathway

“…The data reported here provide a basis for comparison to similar studies of patients with retinal abnormalities associated with cerebellar defects (Hamilton et al, 1990 ;To et al, 1993 ;Abe et al, 1997). In most cases, the patient phenotypes can be distinguished clearly from that seen in the nervous mouse.…”

“…In most cases, the patient phenotypes can be distinguished clearly from that seen in the nervous mouse. For example, Hamilton et al (1990) reported a series of patients with autosomal dominant cerebellar ataxia in which cone function was selectively impaired and the rod ERG was not different than normal. In addition, Abe et al (1997) reported that some patients with spinocerebellar degeneration may evidence only mild ERG changes that are restricted to the high frequency oscillatory potentials.…”

“…Oberdick et al, 1990), and that retinocerebellar degenerations present with retinal phenotypes that may be distinguished based on studies of retinal function (Hamilton et al, 1990 ;To et al, 1993 ;Gouw et al, 1994), raise the possibility that the nervous defect may involve cells of the inner retina. The specific studies conducted here involved histological analysis of the cellular and plexiform layers that comprise the inner retina and electrophysiological recordings of the visual pathway made under conditions that allow the activity of different classes of cells to be assessed.…”

Spinocerebellar degeneration with negative electroretinogram: dysfunction of the bipolar cells

“…Pigmentary degeneration of the retina has been reported in association with SCD [7,8]. Impairment of the function of photoreceptors, evaluated with ERGs in SCDs, has been reported [9,10]. In contrast, few have reported dysfunction of the inner nuclear layer of the retina in SCD patients.…”

Spinocerebellar Ataxia Type 7 (SCA7) Shows a Cone–Rod Dystrophy Phenotype

“…If full ®eld ERGs were performed, the results could be normal or abnormal. If rod and cone selective stimuli were used in the ERG studies, abnormalities tended to be more prominent in cone-mediated responses or in both cone and rod signals (Bjo Èrk 1956;Jampel 1961;de Jong et al, 1980;Hamilton et al, 1990;Neetens et al, 1990;. It can be assumed that many of these families had SCA7.…”