A surface ultrastructure study of ganglia and digital mucous cysts

Three digital mucous cysts and three dorsal wrist ganglia were studied by light and scanning electron microscopy. Both exhibited the same findings, namely a porous network of collagenous fibers forming the wall and a fibrillated inner surface composed of a random arrangement of collagen fibers. An intermittent thin membrane was observed on the inner surface, but no evidence of a cellular lining was apparent. This anatomic study lends support to a shared cause.