Ceroid-lipofuscinosis (Batten's disease). Sequential electrophysiologic and pathologic changes in the retina of the ovine model

The sequential electrophysiologic and pathologic changes in the retina in ceroid-lipofuscinosis were recorded in a time-course study in the ovine model. Over a relatively short period in the course of the disease, a severe reduction in both rod and cone b-wave amplitudes developed with rod b-wave changes preceeding those of cones. These changes paralleled a similar loss of rod and cone photoreceptor cells. In affected retinas, outer segments appeared shorter than normal. By 84 weeks of age, the outer nuclear layer was reduced to the width of a single nucleus. In addition to these changes, electronmicroscopy showed the formation of abnormal dystrophic rod and cone outer segments in photoreceptor cells. Most cells in the retina showed the accumulation of a fluorescent lipopigment, this being most prominent in ganglion cells. Ultrastructural studies showed them to be made of electron dense granular material and a variety of membranous and tubular arrays.