The need of standardization in dermatology

There is a lack of standards in dermatology across the entire spectrum of imaging (acquisition, storage, and visualization).

It represents a barrier in the earlier detection of skin cancer, in the monitoring of the evolution over time of skin lesions, in the accuracy of the diagnosis[1]. Standards are needed to ensure quality, privacy and interoperability (e.g. to get interchangeability of image records). Without a standardization, differences in techniques used to acquire, process and visualize images and different technologies in imaging devices can produce inconsistent results[2] e.g. in sequential dermoscopy imaging (SDI) and misdiagnosis.

There are various areas of interest for standardization such as:

  • Definition of requirements of image features (e.g. color accuracy and consistency, spatial resolution, image magnification, image compression, depth of field);
  • color calibration of cameras and monitors (hardware or software-based calibration methods),
  • post-acquisition image processing,
  • image storage.

Currently, even in high end systems, these aspects are managed with an inherently proprietary approach.

Standardization is needed also in image-associated metadata i.e. a consistent terminology for technical (e.g., image type) and clinical (e.g., anatomic site) data. It will allow interchangeable systems and methods for filtering images and will have a beneficial impact in the development of artificial intelligence in the medical sector and specifically in dermatology.

In addition clear benefits of standardization in dermoscopy are[3]:

  • forcing digital videodermoscope or dermoscopy camera producers to provide real high-end, calibrated equipment;
  • having the potential to eliminate the proliferation of non-standard (and therefore barely comparable) sequential dermoscopy imaging (SDI) follow-up;
  • allowing easy and, most importantly, effective sharing of patient’s data among medical professionals.

Examples of standardization efforts for dermoscopy

Standardization efforts are ongoing; we report the activities that are in progress by the International Skin Imaging Collaboration (ISIC) and by the Working Group 19 of DICOM (the Digital Imaging and Communications in Medicine).    

The International Skin Imaging Collaboration (ISIC) (https://www.isic-archive.com/).

An article, previously published in the iToBoS web site, highlighted the ISIC effort in creating resources for the dermatology and computer science communities, including a large and expanding open-source public access archive of skin images, that can be used for teaching, research, and for the development and testing of diagnostic artificial intelligence algorithms. 

In addition four working groups of ISIC are involved in the definition and creation of a set of standards. More specifically:

  • The Technology Working Group has the task of developing standards for minimum functional capabilities for the setting and equipment used in the acquisition, processing, compression, display, printing, archiving, retrieval, and storage systems and to secure the transmission of clinical and dermoscopic images. Points of attention are: resolution and colour; privacy and interoperability in sharing images across technology and clinical platforms;
  • The Technique Working Group is dealing with standards specifying minimum requirements for physical conditions that may significantly affect the quality, consistency and comparability of clinical images (lighting, background color, camera position, equipment calibration and maintenance, image metadata, standard patient poses, and lesion magnification).
  • The Privacy Working Group is developing standards for obtaining patient consent, protecting patient privacy, and preventing unauthorized access to patient images.
  • The Terminology Working Group is in charge of developing a lexicon of standardized terms to describe anatomic sites, clinical features, dermoscopic characteristics, and diagnoses of skin lesions. It is intended to facilitate teaching, content-based-image-retrieval, and consistent application of ground truth for training and implementing AI algorithms;
  • Finally the Metadata / DICOM Working Group is fostering the adoption of the DICOM standard for use in dermatology (dermoscopy, total body photography, and reflectance confocal microscopy imaging).

[1] Hibler BP, Qi QC, Rossi AM. Current state of imaging in dermatology. Semin Cutan Med Surg. 2016;35:2–8. doi: 10.12788/j.sder.2016.001

[2] B. Dugonik et al. – Image quality assessment of digital image capturing devices for melanoma detection – Appl. Sci. 2020, 10, 2876, doi:10.3390/app 10082876; www.mdpi.com/journal/applsci

[3] C. Pagliarello, I. Stanganelli, G. Fabrizi, C. Feliciani and S. Di Nuzzo: “Digital Dermoscopy Monitoring: Is it Time to Define a Quality Standard?” - Acta Derm Venereol 2017 Jul 6;97(7):864-865; doi: 10.2340/00015555-2663.