Cochlear Explorers – Part VI – Rosenthal’s Canal

Welcome to part VI of Hearing Ice65nternational’s series honoring the Cochlear Explorers.  Recall that there are lots of cells and other structures within the body named after the researchers who first described them; their names are called Eponyms

This week’s Cochlear Explorer is the often mistakenly referenced Friedrich-Christian Rosenthal (1780–1829) an anatomist born in Greifswald, Germany. While there is some discussion of  an even earlier description of the canal by  Samuel Thomas Soemmerring who may have illustrated the inferior half of the spiral canal as early as 1806, Rosenthal is the anatomist credited with the discovery of the Spiral Canal with the cochlea.   

Rosenthal’s Canal (Canalis Spiralis Cochleae)

 The electronmicrograph at right presents a transverse section of the cochlear duct. Within the petrous portion of the temporal bone, the auditory receptors are housed in a bony, coiled canal, called Rosenthal’s Canal or, anatomically, the canalis spiralis cochleaeThe winding tube of the bony labyrinth which makes two and an half turns about the modialius of the cochlea, it is divided incompletely into two compartments by a shell of winding shelf of bone, tce66he bony spiral laminaIn his 1823 publication “Ueber den Bau der Spindel im menschlichen Ohr” (Translation:  About the construction of the spindle in the human ear ), Rosenthal corrects Scarpa, with due respect to the master, noting that Scarpa’s representation of the spindle “does not completely agree with nature.” He then describes a “Kanal” (canalis spiralis modioli) that follows the modiolus and observes that all nerve fibers that penetrate through the perforations of the tractus spiralis foraminulentus] reach this canal and then distribute themselves as thin fibers on the spiral plate. Rosenthal’s spiral canal of the modiolus of the cochlea is mentioned numerous times in the literature, but there are few references to the man (Rosenthal) who discovered it or to the 1823 article in which it was first described. 

 Who was Rosenthal?

Rosenthal was first and foremost a general anatomist, also known for his studies on whales, seals, and jellyfish. His study of the ear led to the description of two eponymous structures: the ce6canalis spiralis cochleae canal in the cochlea and the basal cerebral vein. While he is a famous cochlear explorer, Schacht & Hawkins (2004) state that Rosenthal has probably suffered more than most other inner ear anatomists from posthumously mistaken identity. His discovery has on occasion been ascribed to Isidore Rosenthal 1915) [Critchley, 1978; Koenigsberg, 1989], a German anatomist, whose birth postdates the original publication describing the structure.  

Friedrich-Christian Rosenthal earned his doctorate from the Fredrich Schiller University, a public research university located in Jena, Germany and often referred to as the University of Jena.  The University was established in 1558 and is among ce67the ten oldest universities in Germany.  He entered the university in 1797 and earned his doctorate in 1802. His dissertation is entitled De organo olfactus quorundam animalium (Of the olfactory organ of certain animals).  After surgical training in Würzburg and Vienna, he returned to Greifswald in 1804 to settle down in the private medical practice he opened and to work on cr68his habilitation, at the University of Greifswald.  

During the habilitation he worked closely with the naturalist Karl Asmund Rudolphi (1771–1832) and, in 1807 finished the habituation at the University of Greifswald with a treatise on olfaction: De organo olfactus quorundam animalium (Of the olfactory organ of certain animals).   In 1810, he accepted an appointment to the University of Berlin, and in 1820 returned to Greifswald as a professor of physiology and anatomy.  He died in 1829 at the age of 49 due to consequences from tuberculosis.

Next Week watch Hearing International for another Cochlear Explorer, Ernst Reissner

About Robert Traynor

Robert M. Traynor is a board certified audiologist with 45 years of clinical practice in audiology. He is a hearing industry consultant, trainer, professor, conference speaker, practice manager, and author. He has 45 years experience teaching courses and training clinicians within the field of audiology with specific emphasis in hearing and tinnitus rehabilitation. Currently, he is an adjunct professor in various university audiology programs.