Thirty-five millimeter versus digital photography: comparison of photographic quality and clinical evaluation

New insights into facial anthropometry in digital photographs using iris dependent calibration

BACKGROUND

In facial and reconstructive surgery objective assessment of anatomy is crucial to evaluate surgical results. Photographic computer-assisted anthropometry substitutes clinical measurements. The constancy of the horizontal iris diameter (IDh) allows iris dependent calibration of photographs, replacing the need for a scale.

METHODS

We performed a prospective cohort study to assess the constancy of the IDh in children. Frontal and close-up digital photographs of the eyes were taken of 100 children aged 5-18 years. The IDh was measured twice; once with a scale positioned on the forehead (IDh*(forehead)) and once with a scale positioned next to the tragus (IDh*(ear)).

RESULTS

Our data confirms the constancy of the IDh in children from the age of 5, with a mean IDh*(forehead) of 11.22 ± 0.52 mm. We found no difference between gender and no variation with age. For structures that are not in the same coronal plane as the iris, an adjusted iris diameter is needed to compensate for the difference in distance from the camera.

CONCLUSION

We confirm the reliability of iris dependent calibration in frontal photographs from the age of 5. This technique allows evaluation of a wide variety of pre-existing photographs that do not have a scale included, simplifies photographic conditions and facilitates long-term follow-up.

The digital camera in clinical practice

The benefits of digital photography are certainly numerous and include rapid image production, easy and quick deletion of poor images, no need for film or its associated expenses, decreased costs for enlargements, ease of editing and image storage, effortless placement in presentations or publications. Many physicians believe that the benefits of digital images clearly outweigh any limitations that future technologic advances will minimize. Digital imaging allows for the seamless integration of all patient images (e.g., clinical, radiographic, pathologic) into the medical record. Additionally, manipulating these images with lighting, filters, of other processing techniques may encourage diagnostic advances (e.g., distinguishing between benign and malignant surface lesions). Some drawbacks, however, continue to exist, including cost of the hardware and software, continuously evolving technology, power consumption and battery usage, lower image resolution compared with 35-mm photography, and the need to have backup image files. With decreasing costs, improving resolutions, and enhanced capabilities, digital cameras will overcome these limitations rapidly.

Using a computer to organize digital photographs

A facial plastic surgeon's photographic files are a potential storehouse of learning material. Manual review of before-and-after photographs is time consuming and self-limiting. Computers can facilitate the analysis, storage, and review of photographs and thereby serve as an aid to learning from the results of our surgery. This article describes a personal approach to automating this process. The surgeon classifies the photographs, and the office staff performs the typing and filing. As the speed and resources of computers rapidly expand, this process will become faster, simpler, and more popular.