title: Detection of clinically manifest and silent synovitis in the hands and wrists by fluorescence optical imaging.
abstract: OBJECTIVE
  The correct identification of synovitis is critical for achieving optimal therapy results. Fluorescence optical imaging (FOI) is a novel modality based on the use of an intravenous fluorophore, which enables fluorescent imaging of the hands and wrists with increased focal optical signal intensities in areas of high perfusion and/or capillary leakage. The study objective was to determine the diagnostic utility of FOI in detecting apparent and clinically non-apparent active synovitis.
  
  
  METHODS
  Bilateral hand and wrist joints (n=872) of 26 patients with inflammatory arthritis assessed by standard clinical examination, musculoskeletal ultrasound (MSUS) and FOI were studied. Synovitis was defined as tender and swollen joints on clinical examination, presence of synovial thickening and intra-articular Doppler signals on MSUS, and abnormal focal optical signal intensities on FOI, respectively. Subclinical synovitis was defined as being clinically non-apparent, but positively inflamed on MSUS.
  
  
  RESULTS
  Depending on the standard used to define inflammation, FOI ranged from 73-83% sensitive and 83-95% specific for detecting manifest synovitis. For detecting clinically silent synovitis, the sensitivity, specificity and positive and negative predictive values of FOI were 80%, 96%, 77% and 97%, respectively.
  
  
  CONCLUSIONS
  The high degree of agreement between MSUS and FOI suggest its use in clinical practice, especially when MSUS is not available, in order to identify synovitis earlier and with greater confidence. FOI may be particularly useful in identifying patients with clinically non-apparent joint inflammation of the hands and/or wrists.
authors.affiliation: Unit for Clinical Therapy Research, Inflammatory Diseases (ClinTRID), Karolinska Institute, Karolinska University Hospital , Stockholm , Sweden.
authors.forename: Yogan
authors.initials: Y
authors.lastname: Kisten
authors.affiliation: Unit for Clinical Therapy Research, Inflammatory Diseases (ClinTRID), Karolinska Institute, Karolinska University Hospital , Stockholm , Sweden.
authors.forename: Noémi
authors.initials: N
authors.lastname: Györi
authors.affiliation: The Rheumatology Clinic, Karolinska University Hospital , Stockholm , Sweden.
authors.forename: Erik
authors.initials: E
authors.lastname: Af Klint
authors.affiliation: Unit for Clinical Therapy Research, Inflammatory Diseases (ClinTRID), Karolinska Institute, Karolinska University Hospital , Stockholm , Sweden ; The Rheumatology Clinic, Karolinska University Hospital , Stockholm , Sweden.
authors.forename: Hamed
authors.initials: H
authors.lastname: Rezaei
authors.affiliation: Unit for Clinical Therapy Research, Inflammatory Diseases (ClinTRID), Karolinska Institute, Karolinska University Hospital , Stockholm , Sweden.
authors.forename: Adrian
authors.initials: A
authors.lastname: Levitsky
authors.affiliation: The Rheumatology Clinic, Karolinska University Hospital , Stockholm , Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Karlsson
authors.affiliation: Unit for Clinical Therapy Research, Inflammatory Diseases (ClinTRID), Karolinska Institute, Karolinska University Hospital , Stockholm , Sweden ; The Rheumatology Clinic, Karolinska University Hospital , Stockholm , Sweden.
authors.forename: Ronald
authors.initials: R
authors.lastname: van Vollenhoven
keywords: Inflammation; Multidisciplinary team-care; Rheumatoid Arthritis; Synovitis; Ultrasonography