Marx's Line Publication 1924: Critical in Dry Eye Research 86 Years Later (2010)

Why should a translation of a 1924 article by E. Marx1 be of sufficient significance to justify publication in OVS? Remarkably, the line reported in this article is now of prime interest for both understanding the lid margin and for dry eye treatment and diagnosis.2–6 As such, the information in this article, published in 1924 in the German journal “Albrecht von Graefes Archiv für Ophthalmologie,” will provide a valuable reference for all those interested in the lid margin and dry eye. Marx described, for the first time, a line on both the upper and lower eyelids, which stained with rose bengal and other dyes.1 This line of staining, now known as Marx's line (ML), delineates the junction between the keratinized epithelium of the eyelid margin and its junction with the palpebral conjunctiva, nowadays known as the mucocutaneous junction. Until recently, as evidenced by its sparse appearance in the literature, interest in this phenomenon was minimal.7–11 In fact, in 1924 Marx wrote, “Investigators who evaluate the anatomy of the eye in vivo by slit-lamp microscope have shown only minimal interest in the margins of the eyelids and the lacrimal puncta.”1 His comment regarding the margins of the eyelids is, remarkably, still relevant, because we are without adequate answers for a plethora of questions concerning the function and mechanism of action of the lid margins. The details of Marx's original findings would obviously be of interest; however, attempts to translate the 1924 article were thwarted by the style of 1920 scientific German. Both I (Korb) and the profession are indebted to Heiko Pult, a German optometrist, researcher and Fellow of the American Academy of Optometry, who, on my suggestion, provided the initial translation despite being in the middle of writing his PhD dissertation. In addition, Erich Knop, MD, PhD, a native speaking German ocular anatomist and Chair of the Anatomy Subcommittee of the Meibomian Gland Workshop, contributed significantly to the understanding of Marx's complex descriptions. The task of translating the text into contemporary English not only required the four authors to work as a team to refine and distill the translation, but additionally necessitated repeating many of Marx's clinical studies to observe and appreciate his findings, because many of his findings were foreign to the authors, thus hindering translation. The information obtained from repeating his observations allowed effective translation of the article. We were dedicated to conveying the literal beauty of Marx's detailed descriptions, making only those alterations necessary for facile reading. The authors added comments to facilitate the reader's understanding. The article was translated in its entirety, with the exception of a few paragraphs that were not readily understood in today's technical language. The translation provides information that has not been available or commonly understood, including Marx's Line (ML) that delineates two planes of different heights (the epithelium of the conjunctiva is usually elevated relative to that of the adjacent lid epithelium); ML is continuous through the temporal canthi, joining both lids; and ML and the puncta have a variable appearance and elevation from the lid planes from infancy to old age. Marx's work was very specific to the lid margins, particularly the lower margins. We noted the use of many stains that are not in current use for ML and the lid margin in addition to the staining characteristics of various stains and individual cells of ML and the ocular surface. Each of these observations and notes offer research potential, particularly for dry eye conditions. It is of interest to reflect upon the accomplishments of Marx and his untimely demise. The authors are indebted to the Deutsche National Bibliothek (German National Library) for their help in providing insight in to his life. Eugen Marx was born in 1879 in Mannheim, Germany, moved to the Netherlands where he qualified in medicine in 1906. He practiced in Rotterdam and was an important figure in both Dutch and international ophthalmology. He published his works in German and English Journals and authored several books. He was the first secretary of the International Ophthalmological Council, president of several organizations, organized multiple international ophthalmological congresses, and was personally responsible for improving the international communication of ophthalmologists. Marx's career ended tragically when he took his life after the German invasion into the Netherlands (Marx was a Jew). It is remarkable that his work was not acknowledged by many European luminaries, including Eugene Wolff, the ophthalmologist who first reported the three-layer tear film model. Wolff failed to acknowledge Marx when discussing the mucocutaneous junction in any edition of his renowned text books, the Anatomy of the Eye and Orbit,8–10 or in his frequently quoted 1946 article, “The mucocutaneous junction of the lid-margin and the distribution of the tear fluid.”7 We are unable to explain these omissions. Unfortunately, it appears that the lack of appropriate referencing served to curtail the acknowledgment of Marx's contributions from succeeding generations. The publication of the translation of this classical article will provide information that has previously been unavailable in English for reference, and Marx's article will, 86 years after its publication, serve as a new impetus for understanding the role of the Line of Marx, the mucocutaneous junction, and the role of the lid margins in dry eye states. The authors are grateful to the Editor, Anthony Adams, and to OVS for the publication of the translation of this classic. Donald R. Korb Boston, MA