In the 1990s, gas was around $1.15 a gallon, Windows 95 was released, Netscape debuted and the dot-com boom began. The average digital camera was around 5 to 8 megapixels, not a threat to traditional photography yet. Film was still king on the block when it came to high-detailed images. Digital projection was still young and expensive.
Radiology faculty at Cincinnati Children’s would teach residents, fellows and other faculty via lectures or conferences by projecting medical presentations on regular slides. The radiologist would show PowerPoint-generated slides containing text information, charts and graphs. They would also show medical images via x-rays, CT, MRI, ultrasound, and nuclear medicine taken with a normal 35mm camera. A majority of their slide presentations would be just medical images on slides.
Photo: Samples of slides given at a medical lecture. (l-r) Pathology image, image inserted in PowerPoint (PPT) then exposed on to a film slide, PPT slide containing graphs, CT image taken with a 35mm camera.
It was a time-consuming process of creating a slide presentation. The equipment needed to create a slide presentation was a computer (with Microsoft PowerPoint), a photo slide printer, a 35mm camera and a light box to hold/view your x-rays or medical films. Not everyone had a desktop computer back in those days and they were not cheap either. A slide printer would cost in the thousands and the average exposure time per slide was 5 minutes (3hrs per 1 roll of film). In a busy year, Radiology would use 100-200 rolls of film slides. The film supplies alone were around $2,000 per year, and sending the slides out to be processed cost in the thousands.
The Radiology Department had a shoe-box size slide printer that exposed digital information on to a normal photographic slide. A slide printer is quite simply a machine that held a roll of film to be exposed digitally. When that roll of film was completely exposed, it would then be sent over to the local photographic lab to be processed and returned as mounted slides (1-3 days turn-around-time).
Image: Traditional large x-ray medical film.
Another way of capturing medical images was with a traditional 35mm camera, holding 36 frames of slides per roll. Medical images were still printed on large film, such as x-rays, and they were viewed on a lightbox in order for the radiologist to diagnose the study. While on a lightbox, a picture would be taken with a 35mm camera, normally black and white (BW) film slides. Color slides would have a bluish tint (not true BW) to the image when taking photos of BW x-ray films. Radiologist preferred true BW slide films.
Photo: Slides on a small lightbox.
Creating a slide presentation was a very time-consuming project. A radiologist would spend hours gathering data and image samples, creating the PPT file and taking photographs of the medical films. Once all of this was done the photography lab would send back the finished product as slides. There would be many times that the presenter would catch a misspelled word or something out of place and there would be a rush to have it corrected and back in time for their lecture.
Image: Lecture given in our Radiology large conference room; a digital projector is used to show the speaker’s PPT presentation.
As digital technology begin to advance, digital equipment began to decrease in size and become more affordable. Digital SLR cameras were taking images that rivaled film quality. Slowly, slides were replaced with high-end digital projectors. Photo labs and dedicated photographic stores would be less numerous. All you needed now was a computer (with a presentation software) and a digital projector. Mistakes could be corrected on the spot and days of preparations and work were shortened to just hours. The cost became more affordable to the department’s budget as there were no more photographic lab fees and photo supplies. You could screen capture your medical images from the computer screen or insert the file, instead of capturing it with a handheld camera. No longer did a presenter have to take binder-size sleeves of slides; one small USB drive would do. Also, audio and video could be inserted and played on a presentation.
Photo: Digital projection instead of slides.
I’m amazed when I hold in my hands a regular photographic slide, reflecting on how far we have gone from long hours of work to just minutes in front of a computer. A person can almost complete a lecture presentation in front of a computer. A doctor can gather all the necessary information and images via the internet, their hospital’s image archiving system, their cell phones, etc. I wonder what the next evolution in technology will bring?