title: Pilot study assessing pathophysiology and healing of digital ulcers in patients with systemic sclerosis using laser Doppler imaging and thermography.
abstract: OBJECTIVE
  Systemic sclerosis (SSc)-related digital ulcers (DU) cause significant pain and disability and are often a primary endpoint in clinical trials. However, their pathophysiology has been little studied. The objectives of this prospective study were to determine whether laser Doppler imaging (LDI) and thermography can identify ischaemic components in both fingertip and extensor surface DU and assess ulcer healing.
  
  
  METHODS
  Patients prospectively reported new DU over a year. Patients' DU underwent imaging until the ulcer had healed. Ischaemia was defined as lower blood flow or skin temperature (and inflammation as higher) within the ulcer, compared to a non-affected site.
  
  
  RESULTS
  53 ulcers (19 fingertip, 18 extensor, 16 'other' sites) in 17 patients were imaged (53 with LDI, 52 with thermography). For LDI data 32 (60%) ulcers were ischaemic; median perfusion ulcer/unaffected area; 0.79 (range 0.11-2.9). For thermography data 35 (66%) were ischaemic; 0.98 (0.89 to 1.1). Inflammation in the surrounding area was identified for all ulcers by LDI but not thermography. In the 36 ulcers with repeat imaging, LDI showed trends (with healing) towards increased ulcer perfusion (p=0.23) and decreased hyperaemia in adjacent areas (p=0.59). Skin temperature at the ulcer site showed no significant change (p=0.13) but adjacent area showed decreased temperature (p=0.04 signifying decreased blood flow).
  
  
  CONCLUSIONS
  LDI and thermography are sufficiently sensitive to measure ischaemia in both fingertip and extensor ulcers. LDI was better suited to monitoring change in perfusion with healing (due to higher imaging resolution, or vascular changes occurring in more superficial skin layers).
authors.affiliation: Institute of Inflammation and Repair, The University of Manchester, Manchester Academic Health Science Centre, Salford Royal NHS Foundation Trust, Salford, UK; and Photon Science Institute, University of Manchester, UK. andrea.murray@manchester.ac.uk.
authors.forename: Andrea K
authors.initials: AK
authors.lastname: Murray
authors.affiliation: Institute of Inflammation and Repair, The University of Manchester, Manchester Academic Health Science Centre, Salford Royal NHS Foundation Trust, Salford, UK.
authors.forename: Tonia L
authors.initials: TL
authors.lastname: Moore
authors.affiliation: Rheumatology Directorate, Salford Royal NHS Foundation Trust, Salford, UK.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Wragg
authors.affiliation: Institute of Inflammation and Repair, The University of Manchester, Manchester Academic Health Science Centre, Salford Royal NHS Foundation Trust, Salford, UK.
authors.forename: Holly
authors.initials: H
authors.lastname: Ennis
authors.affiliation: School of Community Based Medicine, The University of Manchester, Manchester Academic Health Science Centre, Salford Royal NHS Foundation Trust, Salford, UK.
authors.forename: Andy
authors.initials: A
authors.lastname: Vail
authors.affiliation: Institute of Inflammation and Repair, The University of Manchester, Manchester Academic Health Science Centre, Salford Royal NHS Foundation Trust, Salford, UK.
authors.forename: Graham
authors.initials: G
authors.lastname: Dinsdale
authors.affiliation: Department of Hand Surgery, Salford Royal NHS Foundation Trust, Salford, UK.
authors.forename: Lindsay
authors.initials: L
authors.lastname: Muir
authors.affiliation: Dermatology Centre, The University of Manchester, Manchester Academic Health Science Centre, Salford Royal NHS Foundation Trust, Salford, UK.
authors.forename: Christopher E M
authors.initials: CE
authors.lastname: Griffiths
authors.affiliation: Inst.of Inflammation and Repair, University of Manchester, Salford Royal NHS Foundation Trust, Salford; and NIHR Manchester Musculoskeletal Biomedical Research Unit, Central Manchester NHS Foundation Trust, Manchester Academic Health Science Centre, UK.
authors.forename: Ariane L
authors.initials: AL
authors.lastname: Herrick
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity; D005260:Female; D005385:Fingers; D006801:Humans; D007511:Ischemia / Q000000981:diagnostic imaging* / Q000209:etiology / Q000473:pathology / Q000503:physiopathology; D017078:Laser-Doppler Flowmetry; D008297:Male; D008875:Middle Aged; D055420:Perfusion Imaging / Q000379:methods*; D010865:Pilot Projects; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012039:Regional Blood Flow; D015203:Reproducibility of Results; D012595:Scleroderma, Systemic / Q000150:complications* / Q000175:diagnosis; D012867:Skin / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D012881:Skin Temperature; D012883:Skin Ulcer / Q000000981:diagnostic imaging* / Q000209:etiology / Q000473:pathology / Q000503:physiopathology; D013817:Thermography; D013997:Time Factors; D014945:Wound Healing