Can we use a smartphone for clinical imaging?

Clinical photographs play a crucial role in orthodontic treatment. We commonly use these images for diagnosis, communicating with patients, and monitoring treatment progress. Traditionally, we feel that digital single-lens reflex (DSLR) cameras are the best option for capturing these photographs. However, advancements in smartphone camera technology have led to a growing trend of using smartphones for clinical photography. Despite this shift, we still do not know if there are any significant differences between images taken with smartphones and those captured with DSLR cameras.

A team from Cambridge, London, and Bristol, in the beautiful South of England, examined this interesting subject. The EJO published their paper.

What did they ask?

They did this study to 

“See if there was a difference in the image quality, dimensional accuracy, colour shade accuracy and ease of use of DSLR and smartphone cameras for orthodontic images”.

What did they do?

They did a cross-sectional study to evaluate images from Smartphones and DSLR cameras using the following stages:

1. They identified the four most popular smartphones and three semi-professional DSLR cameras.
2. An experienced operator then took standard orthodontic images using the cameras.
3. A panel of five experienced clinicians assessed the image quality and colour shade accuracy of the images using visual analogue scores.
4. Three experienced operators evaluated the ease of use of the cameras.
5. They then used the manufacturer’s information to evaluate the sensor size.
6. Finally, they looked at dimensional accuracy by taking images at a standard distance from the patient. They then evaluated image distortion between the cameras.

The statistician then constructed linear mixed effects models to evaluate the outcomes. At this point, the statistical analysis was beyond my understanding. But it seemed logical.

What did they find?

These were the main results.

1. The DSLR had a greater sensor size than the smartphone cameras
2. They pooled the data for the types of cameras. When they examined the image quality, the DSLR cameras were superior to the smartphones for every intra- and extra-oral view.
3. There was no difference in the ease of use of the DSLR and the smartphones.
4. The DSLR had better dimensional accuracy than the smartphone.
5. No device was better than the other for colour shade accuracy.

Their overall conclusion was

“A DSLR camera, with a ring flash, should be considered to be the “gold standard” for clinical photography, due to the reduced quality rating and image distortion produced by smartphone cameras”.

What did I think?

Sometimes, the most interesting and useful studies are those that are straightforward. This study fits into that category. The methodology was clear and relevant to the study’s aims, and the team produced a well-written paper.

Importantly, they acknowledged the limitations of their study. Most were minor, but they noted that while the use of Visual Analogue Scales (VAS) was established and relevant, they did not ask the assessors to explain their rationale for the scores.

Nevertheless, this approach allowed them to analyse the data with minimal “white noise.” This is a valid point. However, it also meant that they did not assess whether the images were clinically acceptable.

As a result, we can conclude that while DSLR cameras may be “better” than smartphones for imaging, we still do not know if smartphones can be used effectively. This ultimately depends on our personal standards. If we aim for the highest quality, we should use DSLR cameras. However, if we are willing to accept lower-quality images, smartphones may suffice.

In short, this situation is akin to clinical treatment; our decisions are influenced by our standards and abilities. This paper points us in the right direction.

Key points

My blog software can generate key points for each post. I am trying this for the next few posts. Can you let me know what you think in the comments?

• Methodology of the Study: The researchers employed a cross-sectional design, capturing images using popular smartphones and semi-professional DSLR cameras. These images were then assessed through expert evaluation, sensor analysis, and distortion measurement.
• Comparison of Smartphone and DSLR Cameras in Clinical Photography: A study evaluated whether there are significant differences in image quality, dimensional accuracy, color shade accuracy, and ease of use between smartphone cameras and DSLR cameras for orthodontic images.
• Key Findings on Image Quality and Accuracy: DSLR cameras produced superior image quality and dimensional accuracy compared to smartphones, though no differences emerged in color shade accuracy, and ease of use was comparable for both device types.
• Implications of the Results: While DSLR cameras are considered the ‘gold standard’ for clinical photography due to better image quality, smartphones may still be adequate depending on individual standards for image acceptability.
• Study Limitations and Conclusions: The study acknowledged limitations, including not assessing clinical acceptability of images, but overall suggests that DSLR cameras remain the preferred choice for high-quality clinical images, whereas smartphones could be acceptable depending upon standards.