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Otto Lowenstein, Pioneer Pupillographer

Thompson, H. Stanley MD

Journal of Neuro-Ophthalmology: March 2005 - Volume 25 - Issue 1 - pp 44-49

Otto Lowenstein, a pioneer in the study of pupil function, began his professional life as an academic neuropsychiatrist at the University of Bonn with an interest in experimental psychology. From his teacher Alexander Westphal, he developed a fascination with the pupil. He invented ingenious recording devices and took motion pictures of the pupils, graphing their movements. Forced to flee Nazi persecution in 1933, he took temporary refuge in Switzerland and eventually sacrificed a flourishing career in Europe to escape to New York. During the next 25 years, he collaborated with Irene Loewenfeld on experiments and publications related to the clinical use of pupillary signs and introduced pupillography to American neuro-ophthalmology.

Address correspondence to H. Stanley Thompson, MD, Ginniff Brooks, 2096 Krestel Ridge SW, Oxford, IA 52322; E-mail:

Otto Lowenstein was the middle of five children born in 1889 to Julius Loöwenstein, a Jewish merchant in Osnabruück, Germany, and to Henriette Loöwenstein (Fig. 1).

He grew to be a small, quiet, thoughtful boy. At age 12, he was believed to have lung trouble and was sent for a year to live with a family in the Black Forest so that he could breathe clean country air. He read a lot of books (1,2). His lungs proved to be healthy.

At age 19, he entered the University of Goöttingen, studying mathematics and philosophy. He then started a medical course and transferred to the University of Bonn, where he received his license to practice medicine in 1914. It was a bad month for the world; he was promptly drafted into the army as a physician.

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The young doctor Lowenstein was chiefly interested in measuring bodily movements by means of instruments that could make recordings (Figs. 2-4). He invented a device to document differences between organic and psychogenic tremor in shell-shocked soldiers (Fig. 2). Other gadgets were used to record deep tendon reflexes (Fig. 3) and document an unsteady stance (Fig. 4).

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After the war, Lowenstein returned to Bonn to train in neuropsychiatry under Professor Alexander Westphal (1863-1941), whose name is attached to the Westphal-Piltz phenomenon of pupillary constriction with forced lid closure. (Alexander Westphal's famous father was Karl Friedrich Otto Westphal [1833-1890], professor of psychiatry and neurology the University of Berlin and teacher of Pick, Oppenheim, and Wernicke, and it is his name that is attached to the Edinger-Westphal nucleus.) It was Alexander Westphal who stirred Lowenstein's interest in the pupil (see Side Bar).

Lowenstein stayed on at the University of Bonn as Privatdozent and later as Oberarzt and Auserordentlicher Professor. During that period, he took a special interest in pediatric psychiatry as illuminated by the developing field of experimental psychology. By 1926 he was the medical director of the Provincial Children's Hospital, and within 3 years his activities had filled the 60 beds. In 1929 he made plans for a new building in the modern style with room for nurses' quarters, dormitories, and classrooms. The upper floors contained laboratory space. There he began to make motion pictures of patients with epileptic seizures (Fig. 5).

He was intrigued that pupil diameter seemed to vary with the state of the patient's emotions. He interpreted this phenomenon to mean that the pupils were not only hardwired by the nerves to the light reflex and near reflexes but also were influenced by psychologic states.

If he could document the details of pupillary movements with a movie camera, he reasoned, it might offer a new and interesting window on brain activity. Several years would go by, however, before photographic film became sensitive enough to allow him to display pupillary movements. (Fig. 6)

In 1926, only 6 years out of training, he became of the director of Die Rheinische Provinzial-Kinder-Heilanstalt für seelische Abnorme, the first institute in Europe to be devoted exclusively to pediatric and adolescent psychiatry (3).

His new laboratories required a trustworthy machine shop (Fig. 7), and indoor and outdoor activities were organized to keep the children occupied (Fig 8).

By careful instrumentation and documentation, he hoped to reach a firm diagnosis, while at the same time learning, by searching family trees, the genetics of psychiatric disease. To this end, he arranged for massive accumulations of old hospital records and family information from surrounding hospitals (Fig. 9). He had set himself a task that would have taken several lifetimes!

He would have been a logical successor to his teacher Westphal, who was to retire from the professorship of psychiatry and neurology, but opposition was emerging from members of the faculty who favored the policies of the new Nazi Party.

The leader of the opposition was Professor Walther Poppelreuter (1886-1939) (4), a man who had made significant contributions to neuro-ophthalmology and neuropsychology. During the 1914 to 1918 war, Poppelreuter was a military doctor in a position to examine patients with head injuries. He took a particular interest in the "filling-in" phenomenon in the blind hemifield and was the first to suggest that there might be a part of the cortex with the task of managing color vision. He spoke of a cortical area that, when damaged, produced dyscalculia (later incorporated into Gerstmann's syndrome).

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Very soon after the Nazis came to power, Lowenstein received a telephone call saying that the Gestapo was after him. Within an hour, he was in hiding and soon he and his family were in flight to Switzerland. One can only wonder what perverted use was made of his collection of family trees with its associated medical information. Enough of his patients were killed or sterilized by the Nazis during the next few years that the University of Bonn felt obliged to actively participate in a national apology to their families in the 1950s.

After being forced to abandon all of their possessions, including the scientific data, films, instruments, and other equipment, Lowenstein and his family set up a new life in Switzerland. There he found work as a consultant neuropsychiatrist at the Clinique La Métairie in Nyon, on the shore of Lac Léman. At first he would not believe that the Nazi Party could last very long and he contemplated eventual return to Germany. In the meantime, he published his work in Swiss and French journals.

But he soon saw that the Nazi party was only getting stronger, its malicious policies abundantly clear. In 1938 came reports of "Kristallnacht," a night when mobs of Nazi youth went on a rampage looting shops, defiling synagogues, and killing Jews. In Osnabrück, his hometown, the famous old synagogue on Roland Strasse was burned to the ground. Lowenstein knew that for the safety of his family, he should make plans to escape from Europe. Abandoning an esteemed academic reputation based on 49 publications on experimental psychology, he left in 1939 for New York.

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The professor soon had a part-time private practice and an appointment at New York University. Having published 21 articles on pupillary topics, he returned to his old interest and set up a pupillography laboratory at New York University (Fig. 10).

The next year, Irene Loewenfeld (Fig. 11) joined him as a technician and eventually as a colleague and a research partner. The research team of Lowenstein and Loewenfeld became well known at New York University and later at Columbia Presbyterian Hospital (Fig. 12).

Lowenstein went on to write another 43 papers on pupillary subjects, 40 of them in English and approximately half of them with Loewenfeld. With Ira Jones, MD, he demonstrated that asymmetric illumination of the two eyes did not induce anisocoria (5). He had made the observation that in sleepiness, the pupils became small and unstable, whereas alerting stimuli would restore their size and normalize their reaction to light. These observations were based on the lessons of Westphal, namely that excitement made pupils large and fixed. Lowenstein suspected that this phenomenon was not simply a matter of peripheral sympathetic outflow to the iris dilator muscle because it also happened in patients with Horner syndrome who had a complete sympathetic denervation (6).

By 1950 he was using two 35-mm movie cameras, one focused on each pupil. The film was projected on a small screen and the pupil diameters were measured by hand with calipers. Loewenfeld suggested methods of improving the experimental equipment and study design. She began a series of experiments with cats, trying to figure out the mechanisms involved when the pupils dilated to an alerting stimulus. It turned out that the stimulus not only tightened the iris dilator muscle by sending impulses out along the well-known cervical sympathetic pathway but also actively inhibited the iris sphincter nucleus in the midbrain. This neural activity served to dilate the pupil by decreasing iris sphincter tone and canceling some of the resistance to the pull of the dilator muscle.

These studies provided a reasonable explanation for what Lowenstein called "central sympathetic activity," and they eventually became Loewenfeld's PhD thesis. The work was published in astonishing detail in 1958 (7). It had become apparent to Lowenstein and Loewenfeld that the drowsy "nodding off" of the pupil coincided precisely with the waves of sleepiness that preceded the drooping of the eyelids and the head (8). These observations led to the use of pupil monitoring in sleep clinics at the Mayo Clinic by Robert Yoss, MD (9), at the University of Tübingen by Barbara Wilhelm, MD (10), and by Sharon Merritt, EdD, RN at the University of Illinois Center for Narcolepsy Research (11).

In 1957, Lowenstein and Loewenfeld built the "electronic pupillograph," incorporating infrared technology developed by the United States Navy and early television technology that allowed for a mechanically generated infrared raster that measured the widest horizontal pupil diameter with great safety, accuracy, and dependability. Their pioneering efforts gave rise to the modern generation of pupillographic instruments.

In 1964, Lowenstein and Loewenfeld outlined a massive textbook on pupillary function, but the professor was found to have pancreatic carcinoma. In that year, at the age of 74, Lowenstein was honored in Bonn as a pioneer of child psychiatry and experimental psychology. He died in New York in 1965. Nearly 40 years later, a new children's psychiatric clinic opened at the University of Bonn that was named Das Professor Otto Löwenstein Haus.

In the 30 years after Lowenstein's death, his cherished colleague Loewenfeld labored on the massive textbook they had started together. Published in 1993 in a small first edition by the Iowa State University Press (12), it was reprinted in 1999 by Butterworth-Heinemann. It remains the standard reference work on the pupil.

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1. Loewenfeld IE. Otto Lowenstein: Neurologic and ophthalmologic testing methods during his Lifetime. Doc Ophthalmol. 1999:98:3-20.
2. Loewenfeld IE, Dr Otto Lowenstein. Surv Ophthalmol. 1965;10:507-509.
3. Waibel A. Die Anfänge der Kinder- und Jugendpsychiatrie in Bonn: Otto Löwenstein und die Provinzial-Kinderanstalt 1926-1933. Landschaftsverband Rheinland. Köln, Germany: Rheinland-Verlag, 2000.
4. Poppelreuter W. Hitler der politische psychologe. Friedrich Mann's pädagogisches Magazin. Langensalza: Beyer & Sohne Vlg, 1934.
5. Jones IS. Anisocoria: Attempted induction by unilateral illumination. Arch Ophthalmol. 1949;42:249-253.
6. Lowenstein O. Der Psychische Restitutionseffekt. Das Prinzip der psychisch bedingten Wiederherstellung der ermüdeten, der erschöpften und der erkrankten Funktion. Basel: Benno Schwabe & Co, 1937.
7. Loewenfeld IE. Mechanisms of reflex dilatation of the pupil. Historical review and experimental analysis. Doc Ophthalmol Proc Ser. 1958;12:185-448.
8. Lowenstein O, Feinberg R, and Loewenfeld IE. Pupillary movements during acute and chronic fatigue: a new test for the objective evaluation of tiredness. Invest Ophthalmol. 1963;2:138-57.
9. Yoss RE, Moyer NJ, Ogle KN. The pupillogram and narcolepsy: a method to measure decreased levels of wakefulness. Neurology. 1969;10:921-8.
10. Wilhelm B, Wilhelm H, Ludtke H, et al. Pupillographic assessment of sleepiness in sleep-deprived healthy subjects. Sleep. 1998;21:258-65.
11. Merritt SL, Schnyders HC, Patel M, Clark G, Basner, RC, O'Neill. Pupil staging and EEG measurement of sleepiness. Int J Psychophysiol. (in press).
12. Loewenfeld IE. The Pupil: anatomy, physiology and clinical applications. Ames, Iowa: Iowa State University Press, 1993.
© 2005 Lippincott Williams & Wilkins, Inc.