In 1851 he received his medical degree at the University of Dorpat (now known as the University of Tartu), and in 1855 became a professor of anatomy at Dorpat. In 1875 he retired from teaching for health reasons.
Reissner is remembered for his anatomical studies of the ear, particularly research concerning the formation of the inner ear. By studying the embryos of birds and farm animals, he was able to determine individual stages involving the formation of the inner ears' labyrinth. From this research he was therefore able to conceptualize formation of the labyrinth in humans. Today, his name is lent to Reissner's membrane, a membrane inside the cochlea of the inner ear.
Another anatomical structure that is named after him is "Reissner's fiber", a refractive longitudinal nerve fiber in the central canal of the spinal cord.