Tag Archives: stereo

Solving the Puzzle of History

 

Our profession enjoys a long and rich history, one that has seen dramatic advancement in technology and techniques that aid in the documentation and diagnosis of eye disease. My personal interest in the history of ophthalmic photography stems from participation in multiple history symposia sponsored by the  American Academy of Ophthalmology’s Museum Committee. In 2011, I was quite honored to be invited to co-chair the symposium Imaging and the Eye, but I think I drew the short straw when we were assigning lecture topics. I was given the task of covering the origins of photography and ophthalmic photography – in a ten minute presentation!

It seemed like a daunting task to somehow cover all that history in such a short talk. But when I started to research the topic, a common theme began to emerge when I came across rivalries, controversies, mistakes, and inconsistencies in the historical accounts related to several important discoveries. Rather than try to force every important milestone or event into a timeline format, I decided to concentrate my lecture on a few important controversies and rivalries. This approach worked well for the symposium, but I ended up with far more material than I could hope to cover in several lectures. And I had barely scratched the surface.

The Pencil of Nature is the first collection of photograph works published in book form by Fox Talbot in 1844.  The photographs were printed separately and then mounted or “tipped in”. Talbot claimed that his photographic process preceded that of Daguerre’s in 1839. A digitized version of this book is available through Project Gutenberg.

During the research process, I found that reconstructing history is somewhat like completing a puzzle. Professional historians traditionally have had access to original source documents to support their historical research. Thanks to digital technology, many of these obscure resources are now publicly available through advanced search engines and extensive online collections of scanned historical journals and documents. New pieces of the historical puzzle often become apparent when you can access these primary documents. The accounts in this series benefit from the availability of newly digitized documents, many of which were originally published over 100 years ago.  The Internet Archives, Project Gutenberg, and Google Books provide access to digitized, publicly accessible books, periodicals, and journals that are now in the public domain by virtue of their age and expiration of copyright.

Advertisements in The Philadelphia Photographer from June, 1886. Jackman and Webster’s landmark article on the first successful fundus photograph is included in this issue of the photographic periodical. It can be accessed and downloaded from the Internet Archives.

Even with access to these amazing resources, there are still some missing pieces of the puzzle. The available literature sometimes contains conflicting information or apparent mistakes between different historical accounts. Some publications have also proven to be difficult to locate, either online or in print. These hard to find references were often published in the decades just prior to routine digital publication (1960’s & 70’s) and may not yet be eligible for inclusion in public domain collections.

Covers from vintage journals accessed through Google Books. The 1894 Transactions of the Ophthalmological Society of the United Kingdom includes a paper on fundus photography by one of the early pioneers, Lucien Howe. The American Journal of Ophthalmology from 1899 includes a description of Thorner’s reflex-free ophthalmoscope. Thorner and others soon adopted the same optical design to build improved fundus cameras.

In piecing this puzzle together, I found that it pays to read all referenced documents that other historians have cited rather than rely on a citation of a “fact” actually being accurate. Mistakes are sometimes made and then blindly repeated or misinterpreted in other accounts. For example, a non-existent reference title was accidentally published in multiple historical reviews. Listed as “Barr E.: Drs. Jackman & Webster, Philadelphia Photographer June 5, 1886”, it combined fragments of two separate references and was most likely an author’s note to search for them both. 1,2

After searching the online archives, I was able to confirm that the combined title doesn’t exist, yet multiple authors include it in their reference list.3,4  The authors may have also been confused because of a typographical error in multiple references. Elmer Barr was listed as author of an 1887 paper in the American Journal of Ophthalmology, as well as another article in the Scientific American Supplement from 1888.1,5  Both of these articles describe the successful capture of a human fundus photo with more recognizable features than previous investigators. The author’s real name was Elmer Starr, but the typographical error was repeated several times causing an early pioneer in fundus photography to fade into obscurity and lose his rightful place in history. Being able to detect these mistakes and correct the historical record of our profession has been fascinating.

Die Photographie des Augenhintergrundes by Friedrich Dimmer is an atlas of fundus photographs, published in 1907. It contains several amazing reflex-free photographs taken with a one-of-a-kind camera of Dimmer’s own design. This book represents a major milestone in ophthalmic photography. It was digitized by The Internet Archives in 2011 with funding from Open Knowledge Commons and Harvard Medical School.

In piecing these puzzles together, what stood out the most were the often bitter rivalries that seemed to overshadow many of the most important discoveries. Photography was born in the Victorian Era, a time of great discovery, invention, and advancement in science and medicine. The Victorian Era roughly coincided with the Belle Epoch in Continental Europe and the Gilded Age in the United States. It was during this period that Darwin, Babbage, Pasteur, Maxwell, Morse, Helmholtz, and many others made important advancements in science, medicine, and technology. As you will see in future installments of this series, it was also a time of fierce competition, rivalry, and controversy. The brilliant minds of the day often had egos to match their great intellect. The race to be listed as the “first” to discover a scientific breakthrough could become an obsession. Eponyms were popular, and just about every important new discovery was named for the person that first described it.

A classic example of this competition and controversy occurred in the feud over the discovery of anesthesia in the 1840’s when American dentist Horace Wells and his former apprentice William Morton both claimed to be the first to discover the use of inhaled anesthesia. Wells had successfully used anesthesia on several occasions, but was discredited after a famously failed public demonstration. Humiliated after this one failure, he became deeply depressed, began abusing chloroform, and eventually committed suicide. Morton didn’t fare much better. He remained obsessed with recognition throughout his life. He tried to patent ether under a different name, and eventually died penniless. The American Dental Association honored Wells posthumously in 1864 as the discoverer of modern anesthesia, and the American Medical Association recognized his achievement in 1870. Morton was similarly recognized later in life and again posthumously. Both were instrumental in this major medical advancement, but their egos prevented them from sharing in recognition of their achievement.

The next few episodes in this historical series explore similar relationships, rivalries, feuds, and debate surrounding several important milestones in the evolution of ophthalmic imaging. Fortunately the ending of each of these stories is slightly less morbid than the anesthesia saga:

The Priority Debate looks at the frantic race for recognition as the inventor of photography in 1839.

Stereo Photography examines the nineteenth century development of the stereoscope and competing theories on stereo vision that resulted in a bitter feud between Wheatstone and Brewster.

The First Human Fundus Photograph will explore the early days of fundus photography including several controversies and professional rivalries, including how Elmer Starr lost his place in history.

From there we will continue to explore the evolution of ophthalmic imaging by taking a look back at important individuals and events that shaped our profession – and hopefully fill in a few more pieces of the historical puzzle.

References:

  1. Barr E. On photographing the interior of the human eyeball. Amer J Ophth 1887; 4:181-183
  2. Jackman WT, Webster JD. On photographing the retina of the living eye. Philadelphia Photographer 1886;23:340-341
  3. Van Cader TC. History of ophthalmic photography. J Ophthalmic Photography 1978; 1:7-9
  4. Wong D. Textbook of Ophthalmic Photography. Inter-Optics Publications, New York, 1982
  5. Barr E. Photography of the human eye. Scientific American Supplement 1888; 650:10388

Celestial Bodies – The Eye and Space

First time viewers of ophthalmic images frequently make the observation that the photos look like something from outer space. Especially when reviewing the round orange retinal photos with their eye doctor, patients often comment, “That looks like the planet Mars.”

Every time it happens I get a chuckle out of it. As if we all truly know what the planet Mars really looks like! But to most people, images of the inside of an eye are foreign and amazing. And there does seem to be a little science fiction aspect to both the appearance of the eye when viewed at high magnification, as well as the technology used to capture these amazing images. There are however, several space analogies that really seem to ring true. Among eye-care professionals, the eyeball is routinely referred to as the “globe”.

Macular Star in a patient with cat scratch neuroretinitis

Many clinical findings are named by their appearance rather than an underlying cause, and several conditions have names derived from their similarity in appearance to objects in space: asteroid hyalosis, macular star, star folds, starry sky, astrocytoma, stellate pattern, etc.

Asteroid hyalosis is comprised of calcium soaps suspended in the vitreous cavity behind the iris. Despite their appearance, most patients with this condition are asymptomatic.

In fact, there are enough conditions like this, that I’ve been able to compile them into the Ophthalmic Jeopardy category: Celestial Bodies.

Transillumination of a thinly pigmented iris in a patient with ocular albinism.

Like images from space, there does seem to be an element of wonder and mystery when we peer inside the globe, so in some ways the analogy makes sense.

Cataract

Many ophthalmic images seem reminiscent of photographs from NASA. Or they may stir our imagination or perception of how objects in space might appear.

Lisch nodules on the iris of this patient with neurofibromatosis are reminiscent of peaks, valleys and craters seen in NASA photographs from planets or moons in our solar system.

There are other connections as well. Some of the photographic techniques used by both astronomers and ophthalmic photographers are actually similar. IR capture, interferometry and stereo imaging are common techniques in both fields.  The principles of  rotational stereo imaging can be applied to both subjects. Filters or lasers of different wavelengths are commonly used to enhance visibility of certain features in both subject types.

Most of these analogies between the eye and outer space, are loose associations rather than a direct connection. There is however, at least one eye condition that can be directly associated with a celestial body. Solar retinopathy is a type of photic injury to the retina that is the result of staring at the sun. This condition typically occurs in patients with psychiatric disorders or under the influence of hallucinogenic drugs.

A case of solar retinopathy with a subtle yellow-white foveal lesion with associated early pigmentary changes.

Some scholars believe that early astronomers, especially Gallileo, went blind as the result of solar retinopathy from viewing the sun through a telescope. It’s important to note that this condition can also occur from viewing a solar eclipse without protective eyewear. The upcoming solar eclipse visible in the U.S. on August 21, may cause a spike in cases of solar retinopathy presenting to emergency rooms and eye clinics. The American Academy of Ophthalmology offers some tips for safe viewing of the eclipse.

In recent years, another connection between outer space and vision has been discovered. It turns out that space travel can have some damaging effects on the human eye. Long-term exposure to microgravity can lead to a hyperopic shift in vision from flattening of the globe. This condition is believed to be related to increased intracranial pressure and is sometimes associated with optic disc edema, cotton wool spots and choroidal folds. Optical coherence tomography (OCT) is used to document  changes in thickness of the retinal nerve fiber layer of astronauts before, during, and after space flight.

I took this OCT selfie a few years back when we had a scientist from NASA visiting our clinic while exploring the possibility of putting an OCT on the International Space Station. She wanted to see the Heidelberg Spectralis in clinical use. After demonstrating on several patients, the scientist asked me if I thought it were possible for someone to take an OCT image of themselves. I pivoted the monitor, control panel, and footswitch around so I could operate the OCT from the patient chair and then captured some images of my own retina. I was showing off a little and smugly cautioned the NASA doctor that this was a difficult feat that only an experienced ophthalmic imager could perform. After all, I’ve been doing this for over thirty years. She paused for a moment and then said, “With all due respect, astronauts are some of the smartest and most talented people on earth. They shouldn’t have any difficulty performing OCTs on themselves after a some brief training.” Suddenly I didn’t feel so smug.

A year or so later, the Spectralis arrived at the International Space Station and it looks like she was right. I heard from some colleagues at Heidelberg that the astronauts were given less than 30 minutes of training on the instrument and mastered it quickly!

It’s pretty cool knowing that astronauts are performing ophthalmic imaging on the International Space Station. I wonder if they ever see any resemblance between the eye and celestial bodies?

Disclosure: I have no financial or proprietary interest in the Heidelberg Spectralis.

Here are some links on the condition that’s effecting the vision of astronauts and the use of diagnostic imaging on the space station:

http://www.vision-research.eu/index.php?id=858

https://www.theatlantic.com/science/archive/2017/01/seeing-in-space/513650/

http://www.utsouthwestern.edu/newsroom/news-releases/year-2017/jan/vision-levine.html

https://www.washingtonpost.com/news/speaking-of-science/wp/2016/02/11/cosmic-breakthrough-physicists-detect-gravitational-waves-from-violent-black-hole-merger/

https://www.healio.com/ophthalmology/retina-vitreous/news/print/ocular-surgery-news/%7B5cd3865b-b1db-473a-8800-e3e3b50c6df5%7D/monitoring-long-term-effects-on-vision-in-microgravity-a-priority-for-nasas-future-flight-to-mars