Matthew J S Parker1,2,3, Michael T Oliffe1,2, Neil W McGill1,2. 1. a Department of Rheumatology, The Institute of Rheumatology and Orthopaedics , Royal Prince Alfred Hospital , Camperdown, Sydney , Australia. 2. b Sydney Medical School , The University of Sydney , Sydney , Australia. 3. c NIHR Manchester Biomedical Research Centre , Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, The University of Manchester , Manchester , UK.
Abstract
OBJECTIVES: The primary aim was to evaluate the diagnostic performance of digital photographs taken with a smartphone camera using both a lens attachment and, separately, a dermatoscope. The secondary aims were to assess the influence of prior capillaroscopy experience and familiarity with the novel techniques on diagnostic accuracy. METHODS: All patients referred for capillaroscopy between May 2016 and January 2017 were eligible for inclusion. Nailfolds were classified by widefield microscopy before proceeding double-blinded to nailfold photography using both novel techniques. Randomised photographs were assessed by three independent investigators and results were compared to widefield microscopy. Sensitivity, specificity, inter- and intra-observer variability were calculated. RESULTS: Sixty-five participants contributed over 1000 digital photographs for assessment. The 'smartphone-lens' technique performed with moderate sensitivity (65%; 58-72) and high specificity (90%; 84-96). The 'smartphone-dermatoscope' technique performed with higher sensitivity (74%; 66-82) and excellent specificity (95%; 88-100) and was used more accurately by a novice. Prior assessor experience with nailfold capillaroscopy in general and prior experience with the novel techniques positively modulated the diagnostic accuracy. CONCLUSION: New technologies, in this case utilising a smartphone camera, could help to improve accessibility to nailfold capillaroscopy, an important diagnostic tool and putative biomarker in scleroderma-spectrum disorders, whilst retaining accurate results.
OBJECTIVES: The primary aim was to evaluate the diagnostic performance of digital photographs taken with a smartphone camera using both a lens attachment and, separately, a dermatoscope. The secondary aims were to assess the influence of prior capillaroscopy experience and familiarity with the novel techniques on diagnostic accuracy. METHODS: All patients referred for capillaroscopy between May 2016 and January 2017 were eligible for inclusion. Nailfolds were classified by widefield microscopy before proceeding double-blinded to nailfold photography using both novel techniques. Randomised photographs were assessed by three independent investigators and results were compared to widefield microscopy. Sensitivity, specificity, inter- and intra-observer variability were calculated. RESULTS: Sixty-five participants contributed over 1000 digital photographs for assessment. The 'smartphone-lens' technique performed with moderate sensitivity (65%; 58-72) and high specificity (90%; 84-96). The 'smartphone-dermatoscope' technique performed with higher sensitivity (74%; 66-82) and excellent specificity (95%; 88-100) and was used more accurately by a novice. Prior assessor experience with nailfold capillaroscopy in general and prior experience with the novel techniques positively modulated the diagnostic accuracy. CONCLUSION: New technologies, in this case utilising a smartphone camera, could help to improve accessibility to nailfold capillaroscopy, an important diagnostic tool and putative biomarker in scleroderma-spectrum disorders, whilst retaining accurate results.
Authors: Michael Berks; Graham Dinsdale; Elizabeth Marjanovic; Andrea Murray; Chris Taylor; Ariane L Herrick Journal: Rheumatology (Oxford) Date: 2021-08-02 Impact factor: 7.580