Morphology and localization of sunburst varicosities: an electron microscopic and morphometric study

The results of light and electron microscopy of 18 punch biopsies of sunburst varicosities are presented. Sunburst varicosities are widened cutaneous veins located within the superficial vessel net as well as within descending branches, often with an asymmetrically thickened wall. The thickened vessel walls contain collagenous and muscle fibers. Only a few elastic fibers have been detected, as opposed to numerous oxytalan fibers. Electron microscopy reveals an interfibrillar collagenous dysplasia, lattice collagen, and some matrix vesicles. The center of sunburst vessels is found at depths ranging from 175 to 382 microns below the stratum granulosum.