Contributed by Jessica Tan, MD (Cand)

Theodor Ruete was born in Scharmbeck, Lower Saxony Germany on May 2, 1810. He was a prominent German ophthalmologist most notable for his inventions of the first ophthalmotrope and the first indirect ophthalmoscope.

Ruete entered the field of ophthalmology at a time when it was just establishing itself as a separate specialty. After obtaining a medical doctorate from the University of Gottingen in 1834, he became an assistant to the prominent ophthalmologist Dr. Karl Himly for four years. He then served a teaching role until he was promoted to professor extraordinarius and then professor ordinarius of medical faculty in 1841 and 1847, respectively.[1,2] In 1852, Ruete became the chair of ophthalmology at the University of Leipzig –marking him as the first full professor of ophthalmology in Germany.[1] As chair, he expanded ophthalmological training for medical students and created a one-year residency program in the specialty.[3] He simultaneously served as director of the university’s eye sanatorium focused on providing free eye care for the poor—increasing the number of beds and advocating for free train tickets for patients who could not afford the transportation. [3]

In his early career, Ruete had taken an interest in studying ocular movement and strabismus. He developed a mechanical model to visualize eye movement he coined the “Ophthalmotrope”.  Announced in his 1845 publication titled Des Ophthalmotrope, his first model consisted of an artificial eye in nested gimbals[4] that later improved to a two-eyed apparatus with a weight and pulley system to mimic ocular muscles.[5] The device was intended to be used for teaching demonstrations and to aid research.[4] By understanding the quantitative contribution of each individual muscle to ocular alignment, it assisted strabismus surgeons like himself to determine the degree of muscle shortening in corrective myomectomies.[4,5]

In 1852, Ruete was the first to modify Hermann von Helmholtz’s 1851 invention of the direct ophthalmoscope thereby creating the indirect ophthalmoscope.[6] Instead of a series of semi-reflective glass plates, Ruete better-concentrated light using a concave mirror with aperture.[6] While Helmholtz’s ophthalmoscope created an upright virtual image with higher magnification, Ruete’s indirect method created an inverted real image with improved illumination and a larger panoramic view of the fundus.[7] Given that the light sources at the time were limited to candlelight, the increased brightness of the indirect ophthalmoscope was preferable to many physicians.[7]

Ruete was highly regarded by his colleagues, students, and patients. He was described as an affable, liberal-minded, and exceptional gentleman both in social and professional regard.[3,7] His cordial demeanor, collaborative process, and devotion to his field of medicine left a lasting impression on colleagues who knew him well and those who met him briefly.[8]

Theodor Ruete passed away from a sudden stroke in Leipzig, Germany on June 23, 1867. His legacy lives on as one of the early pioneers of ophthalmology – a brilliant leader whose contributions would help define the field of ophthalmology and provide indispensable diagnostic tools needed to set the stage for the modern practice of ophthalmology.