Ernst Reissner (; 24 September 1824 – 16 September 1878) was a

Baltic German Baltic Germans (german: Deutsch-Balten or , later ) were ethnic German inhabitants of the eastern shores of the Baltic Sea, in what today are Estonia and Latvia. Since their coerced resettlement in 1939, Baltic Germans have markedly declined ...

anatomist Anatomy () is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having its ...

from

Riga Riga (; lv, Rīga , liv, Rīgõ) is the capital and largest city of Latvia and is home to 605,802 inhabitants which is a third of Latvia's population. The city lies on the Gulf of Riga at the mouth of the Daugava river where it meets the Ba ...

Livonia Livonia ( liv, Līvõmō, et, Liivimaa, fi, Liivinmaa, German and Scandinavian languages: ', archaic German: ''Liefland'', nl, Lijfland, Latvian and lt, Livonija, pl, Inflanty, archaic English: ''Livland'', ''Liwlandia''; russian: Ли ...

. In 1851 he received his medical degree at the

University of Dorpat The University of Tartu (UT; et, Tartu Ülikool; la, Universitas Tartuensis) is a university in the city of Tartu in Estonia. It is the national university of Estonia. It is the only classical university in the country, and also its biggest ...

(now known as the University of Tartu), and in 1855 became a professor of anatomy at

Dorpat Tartu is the second largest city in Estonia after the Northern Europe, Northern Europe, European country's political and financial capital, Tallinn. Tartu has a population of 91,407 (as of 2021). It is southeast of Tallinn and 245 kilometres ...

. In 1875, he retired from teaching for health reasons. Reissner is remembered for his anatomical studies of the

ear An ear is the organ that enables hearing and, in mammals, body balance using the vestibular system. In mammals, the ear is usually described as having three parts—the outer ear, the middle ear and the inner ear. The outer ear consists of ...

, particularly research concerning the formation of the

inner ear The inner ear (internal ear, auris interna) is the innermost part of the vertebrate ear. In vertebrates, the inner ear is mainly responsible for sound detection and balance. In mammals, it consists of the bony labyrinth, a hollow cavity in the ...

. By studying the

embryos An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sper ...

of birds and farm animals, he was able to determine individual stages involving the formation of the inner ears'

labyrinth In Greek mythology, the Labyrinth (, ) was an elaborate, confusing structure designed and built by the legendary artificer Daedalus for King Minos of Crete at Knossos. Its function was to hold the Minotaur, the monster eventually killed by the ...

. From this research he was therefore able to conceptualize formation of the labyrinth in humans. Today, his name is lent to

Reissner's membrane The vestibular membrane, vestibular wall or Reissner's membrane, is a membrane inside the cochlea of the inner ear. It separates the cochlear duct from the vestibular duct. It helps to transmit vibrations from fluid in the vestibular duct to the ...

, a

membrane A membrane is a selective barrier; it allows some things to pass through but stops others. Such things may be molecules, ions, or other small particles. Membranes can be generally classified into synthetic membranes and biological membranes. B ...

inside the

cochlea The cochlea is the part of the inner ear involved in hearing. It is a spiral-shaped cavity in the bony labyrinth, in humans making 2.75 turns around its axis, the modiolus. A core component of the cochlea is the Organ of Corti, the sensory org ...

of the inner ear. Another anatomical structure that is named after him is

Reissner's fiber Reissner's fiber ''(named after Ernst Reissner)'' is a fibrous aggregation of secreted molecules extending from the subcommissural organ (SCO) through the ventricular system and central canal to the terminal ventricle, a small ventricle-like str ...

, a long, fibrous aggregation of

glycoproteins Glycoproteins are proteins which contain oligosaccharide chains covalently attached to amino acid side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification. This process is known as glycos ...

secreted by the

subcommissural organ The subcommissural organ (SCO) is one of the circumventricular organs of the brain. It is a small glandular structure that is located in the posterior region of the third ventricle, near the entrance of the cerebral aqueduct. The name of the SC ...

in the

third ventricle The third ventricle is one of the four connected ventricles of the ventricular system within the mammalian brain. It is a slit-like cavity formed in the diencephalon between the two thalami, in the midline between the right and left lateral v ...

and extending through the

central canal The central canal (also known as spinal foramen or ependymal canal) is the cerebrospinal fluid-filled space that runs through the spinal cord. The central canal lies below and is connected to the ventricular system of the brain, from which it r ...

of the

spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spi ...

.
Mondofacto Dictionary, definition of eponym

References

Sketches of Otohistory

Archives of Otolaryngology, Ernst Reissner 1824-1878 105:434-435, 1979 1824 births 1878 deaths Physicians from Riga People from Kreis Riga Baltic-German people Anatomists from the Russian Empire University of Tartu alumni Academic staff of the University of Tartu {{Germany-med-bio-stub