Smartphones and tablets – the sequel
couple of weeks ago I wrote a column about LBMs (little black machines). The article had so many clicks that I wondered what attracted such a wide audience to read it. There was no outcry; people seem to know and accept that the ever sprawling use of mobile phones in front of others can be ill-mannered and antisocial. The comments I received were rather favorable, interspersed with some remarks that certain uses of tablet computers and smartphones in hospital and private practice can be helpful and make life easier for both patients and doctors. I agree.
In the column, I cited an article from the International Herald Tribune:
"Matt Rogers ... led a team of engineers at Apple that wrote software for iPods. He loved his job and working for Apple, he said. But he added: 'In essence, we were building toys. I wanted to build a product that could really make a huge impact on a big problem.'" 
If there is no fitting problem, somebody will create it.
This leads us to the topic of this column: applications of tablets and smartphones in radiology. One of the problems seems to be image-reading outside the department of radiology. To serve as pretext and to give it the right feeling, people call it "emergency reading." I wonder how much emergency reading there is – and where the people want to read.
Tablets and smartphones are beautiful image viewers for certain occasions, but they are amateur tools and don't and won't fulfill minimum standards for workstations used for clinical image interpretation.
For me, an emergency is a situation when you have no other choice other than using your private pick-up as an ambulance or making a tracheotomy with your pocket knife. Reading images of an MR angiography in front of a cozy fire in your fireplace at home is not an emergency.
There are clear rules and regulations for image display devices to optimize clinical safety and workflow, national ones such as the German DIN, and RCR and IPEM in the U.K.; and international ones such as DICOM and ISO. Smartphones and tablets do not even fulfill the minimum standards. Their use for primary diagnosis, clinical image interpretation, is forbidden – correctly so.
Primary display systems are employed for the interpretation of medical images, usually by radiologists. Secondary display systems can be used for showing imaging studies; they must not be used to prepare radiological reports.
The recommended specifications for primary display systems for diagnostic reading are a screen resolution of 1,500 x 2,000 pixels without pixel defects (Class 1), and a screen diameter of 50 cm. The display requires a graphic card that specifies exactly what luminance or density level should be produced for a certain input value, based on the Barten curve, which maps the values into a range that is perceptually linear. Color monitors cannot substitute monochrome displays for the interpretation of CTs. It's a question of image contrast, resolution, and human vision, particularly of male eyes. In general, gray-scale vision is better in all humans. Between 4% and 6% of the population, mostly men, suffer from color vision deficiencies.
On the Aunt Minnie website, I recently read the following quotation:
"'The future is probably a ... solution, perhaps with standards-compliant HTML5 DICOM viewers and, crucially, with no plug-ins and no dependencies,' [the authors of a study] said. 'So you could look at DICOM [images] on anything from your TV to your wristwatch.'" 
Tablets and smartphones are beautiful image viewers for certain occasions, but they are amateur tools and don't and won't fulfill minimum standards for workstations used for clinical image interpretation. Neither will your television or your wristwatch.
I hear an immediate response: "Yes, but ..."
Such outcry isn't helpful. Many people confuse technological advancement with progress, but here we have an about-face, a return to inferior quality. The manufacturer of the DICOM reading software for iPads and iPhones is well aware of that, and they state in the small print: "Not suitable for primary diagnosis." Moreover, as a patient, I wouldn't like my personal data and images spread all over the place. Data should be kept safely in one single, secure storage area. Why not concentrate on something more useful – for the patients' benefit?
1. Rinck PA. Are smartphones changing behavior in medical practice? Rinckside 2011; 22,12: 23-24.
2. Lohr S. Internet technologies prepare for next big phase: everything. International Herald Tribune (Paris), 19 December 2011. 1.
3. Ridley EL. iPad offers value in mobile emergency CT reading. Aunt Minnie Europe. 12 December 2011