Such blindness has been termed "congenital blindness"... Think about your own dreams for a moment. You probably have dreams that contain not only visual effects, but usually auditory or sound effects as well. Some people even report the sense of smell or touch in their dreams. The congentially blind do dream, according to Helen Keller. She addressed the topic of dreams in her landmark work, The Story of my Life. Her dreams are discussed in Part. III, Chap. V.
She, and others report that their dreams are almost totally auditory in nature... filled with sound. Some report,as do sighted persons the phenomena of touch and smell in their dreams. The heightened senses that are remaining tend to dominate their dreaming....