Associations between fluorescence optical imaging and magnetic resonance imaging and symptoms in hand osteoarthritis

Abstract

Objectives To investigate whether Fluorescence Optical Imaging (FOI) enhancement and Magnetic Resonance Imaging (MRI)-defined synovitis are associated with pain and physical function in hand osteoarthritis (OA) patients. Methods Bilateral FOI scans and MRI of the dominant hand were available for 221 patients. Finger joints were examined for tenderness on palpation. Pain in individual finger joints during the last 24 h and last 6 weeks and hand pain intensity by the Australian/Canadian hand index and Numeric Rating Scale were self-reported. On joint level, we applied logistic regression with generalized estimating equations to examine whether FOI enhancement and MRI-defined synovitis were associated with pain in the same joint. On subject level, we applied linear regression to assess whether FOI and MRI sum scores were associated with pain intensity and physical function. Results Metacarpophalangeal and thumb base joints were excluded from analyses due to little/no FOI enhancement. Finger joints with FOI enhancement on the composite image had higher odds (95% confidence interval) of pain during the last 6 weeks (grade 1: 1.4 (1.2–1.6), grade 2–3: 2.1 (1.7–2.6)). Similar results were found for joint pain during the last 24 h and joint tenderness in fingers. Numerically stronger associations were found between MRI-defined synovitis and finger joint pain/tenderness. FOI and MRI sum scores demonstrated no/weak associations with hand pain and physical function. Conclusion FOI enhancement and MRI-defined synovitis were associated with pain in the same finger joint. None of the imaging modalities demonstrated consistent associations with pain, stiffness and physical function on subject level.

Fluorescence optical imaging: ready for prime time?

“…Furthermore, FOI did not demonstrate consistent associations with pain, stiffness and physical function on subject level. 8 However, FOI seems to offer opportunities to distinguish OA vs RA, therefore, it might become a useful tool in differential diagnosis. 6 Moreover, inflammatory enhancements in the skin area of both hands were detected by FOI indicating its potential to study microcirculation in rheumatic diseases with skin involvement.…”

“…The evaluation of the inflammatory intensity in the phases 1-3 and PVM is performed by a semiquantitative (0-3) score called FOIAS (FOI Activity Score). [2][3][4][5][6][7][8][9][10][11][12][13] Recently, the 'Copenhagen scoring method' FOIE-GRAS (FOI Enhancement-Generated RA Score) has been published, which presents a feasible, reliable and responsive single score for synovitis assessment in RA. 14…”

“…Nevertheless, none of the imaging modalities demonstrated consistent associations with pain, stiffness and physical function on subject level concluding that FOI enhancement was probably associated with more noise than established imaging modalities (MRI and MSUS), furthermore FOI did not show enhancement in the thumb base joints, which are commonly affected by OA. 8 Juvenile idiopathic arthritis FOI can also be used in children, as the dosage of the dye ICG can be adapted to the patients' weight. Apart from the particularly good tolerability, interestingly, the children investigated accepted the procedure and showed interest in this method due to the colourful presentation.…”

“…Nevertheless, none of the imaging modalities demonstrated consistent associations with pain, stiffness and physical function on subject level concluding that FOI enhancement was probably associated with more noise than established imaging modalities (MRI and MSUS), furthermore FOI did not show enhancement in the thumb base joints, which are commonly affected by OA. 8 …”

“…Furthermore, FOI did not demonstrate consistent associations with pain, stiffness and physical function on subject level. 8 However, FOI seems to offer opportunities to distinguish OA vs RA, therefore, it might become a useful tool in differential diagnosis. 6 …”