First look into the eye.

PURPOSE: Until Helmholtz's discovery of the ophthalmoscope, it was not possible to visualize the posterior pole of the eye in a living subject. The aim of this work is to emphasize the importance of the invention of the ophthalmoscope because the new era in ophthalmology began with it. METHODS: Available literature concerning this topic was studied, especially by getting in contact with institutes for history of medicine as well as medico-historians in Germany and other countries. RESULTS: Hermann von Helmholtz, German physician and physicist, presented and published his invention of the ophthalmoscope in 1851. Albrecht von Graefe was the first to use ophthalmoscope routinely. He said: 'Helmholtz has opened a new world to us'. The first ophthalmoscope was not easy to use. Some ophthalmologists even thought that ophthalmoscopy is harmful for the eye, particularly for a diseased eye. First, it was used in Germany (A von Graefe), Austria (E Jäger), and Netherlands (FC Donders). In England, it was used only at Moorfields till 1855 (W Bowman). At the First International Congress of Ophthalmology in Brussels 1857, the importance of ophthalmoscopy was stressed. FC Donders said that every view with the ophthalmoscope into the living eye was a new discovery. Among retinal diseases, first were discovered pigment retinopathy (FC Donders) and retinal detachment (A Coccius) in 1853. CONCLUSION: Helmholtz inaugurated modern era in ophthalmology with his magnificant instrument which revolutionized the development of ophthalmology. Von Graefe popularized it. Because of the new findings, ophthalmology was definitely separated from surgery in the middle of 19th century.

Hjalmar Schiøtz, the great Norwegian innovator and his ophthalmoscope.

Recently, the authors encountered an intriguing and largely incomplete ophthalmoscope. The quest to identify and restore it led to a re-evaluation of the evolution of the modern-day ophthalmoscope and a re-examination of the life and contributions of its inventor, the Norwegian ophthalmologist Hjalmar August Schiøtz.

Schultz-Crock binocular ophthalmoscope.

The ophthalmoscope, which is an indispensable tool of our profession, is now taken for granted. It is often forgotten that it was only just over 150 years ago that the first binocular ophthalmoscope was invented. The early instruments were not popular for a variety of reasons. Australians Donald Schultz and Gerald Crock played a major role in improving this instrument and developing the modifications that turned it into an everyday tool of all ophthalmologists.

Allvar Gullstrand (1862-1930)--the gentleman with the lamp.

This is a biography of Allvar Gullstrand (1862-1930) on the occasion of the centennial of his 1911 Nobel Prize in physiology or medicine. We reviewed pertinent literature and we did archival studies at the Uppsala University Library and the Regional State Archives at Lund as well as the Nobel Archives at the Royal Swedish Academy of Sciences in Stockholm. Allvar Gullstrand was a brilliant scientist with an exceptional personality. He gave mathematical descriptions of the dioptric system of the human eye with unprecedented accuracy, and he invented and designed ophthalmological instruments of far-reaching importance. The two most valuable ones are the slit lamp and the reflexless ophthalmoscope. Both are in everyday use by any ophthalmologist in the world. Allvar Gullstrand is so far the only ophthalmologist who has been given a Nobel Prize for work in ophthalmology, and he deserved it well.

75th Anniversary of the Stiles-Crawford Effect(s): a celebratory special symposium, October 23, 2008; Rochester, New York.

There are rather few articles which, so-to-speak, serve to change the landscape in a scientific field. One of those was the discovery of the "directional sensitivity of the retina" by Walter Stanley Stiles and Brian Hewson Crawford (first reported in 1933). Subsequently, their findings were subdivided by Hansen into two logical components, "the Stiles-Crawford Effects of the First and Second Kinds, (SCE- 1 and SCE-2)." The former (SCE-1) dealt with aspects of their research which addressed alterations in perceived brightness of a visual stimulus; the second (SCE-2) was associated with the perceived hue and saturation of these visual stimuli. These discoveries arose out of a failed attempt by W.S. Stiles and B.H. Crawford to measure properly the areas of the entrance pupils of their experimental subjects as part of a research program which addressed problems of glare, e.g., disability glare, in illuminating engineering. Their research was conducted at the National Physical Laboratory (NPL), which is located in Teddington, Middlesex, England. These two fine scientists properly deduced the reason for the failure of their experimental design, and they effectively described and defined a new feature of the visual system which was largely ascribed to the retina. In time, it was realized that this phenomenon was associated in large measure with the waveguide/fiber-optics properties of photoreceptors, and that this was a feature shared by virtually all vertebrate species. This paper is divided into two parts. In the first part, Enoch describes, as best he can, the culture and working conditions at NPL during 1959/60 when he served as a post-doctoral fellow with W.S. Stiles. And in the second part of this paper, the authors describe the findings of W.S. Stiles and B.H. Crawford at the time of their discovery. Today, we celebrate the 75th Anniversary of that research. The organizing committee for this program (alphabetically) is David Atchison, Jay M. Enoch, Vasudevan Lakshminarayanan, and Pieter Walraven. Our group of speakers today will follow with discussions of aspects of subsequent work which has evolved from the initial discoveries made by the late W.S. Stiles and B.H. Crawford.

The ophthalmoscope: Helmholtz's Augenspiegel.

The origins of Helmholtz's invention of the ophthalmoscope are found in the ancient observation that the back of the eye appeared black. In 1703, Jean Méry reported that the luminosity of the cat's eye could be seen when the animal was held under water, and Mariotte observed that a dog's eye was luminous but erroneously thought this was because its choroid was white. Prévost made a breakthrough when he deduced it was incident light and not light coming out of the eye. Purkinje and von Brucke used lenses to attempt to see the fundus and almost succeeded. However, it was Helmholtz who created the first useable ophthalmoscope, whose development and clinical application are traced in this paper. One of the greatest physical scientists in many spheres of learning, his biography is briefly sketched.

On the evolution of binocular ophthalmoscopy.

The need for stereopsis arose soon after the discovery of the ophthalmoscope, not least because the glaucomatous cup was mistaken for a swelling. At that time, Brewster's popular stereoscope was already in use, and its theory and method were then applied to ophthalmoscopy by Giraud-Teulon. His was the first binocular instrument, subsequently much improved by Zachariah Laurence. Binocular indirect ophthalmoscopy was abandoned toward the end of the 19th century in favor of direct monocular ophthalmoscopy, until it was revived in the 1950s by Schepens.

The relaxed confocal scanning laser ophthalmoscope.

The development of the Scanning Laser Ophthalmoscope is reviewed from a historical perspective. Since a flying-spot scanning principle for an electro-optical ophthalmoscope was first disclosed in 1950, enabling milestones have included the introduction of the laser and inversion of the usual Gullstrand's configuration of optical pupils in 1977, and the application of the optical principle of confocality by means of double or de-scanning in 1983. As a result, high resolution and high contrast confocal infra-red ophthalmoscopy with a 790 nm diode laser, at video rates, is a major novel imaging modality when compared to traditional optical techniques. This imaging mode is ideal to provide the necessary fiducial landmarks for microperimetry, therapeutic laser and SD-OCT based optical sectioning of the retina. DPSS or He-Ne lasers emitting at 532, 543, 561 or 575 nm are used for complimentary red-free fundus imaging. The diode 790 nm and DPSS 490 nm lasers are also used for fluorescence excitation.