Rheumatoid Arthritis (RA) is a chronic systemic inflammatory disorder that primarily affects joints, often leading to functional impairment. Magnetic Resonance Imaging (MRI) scanners allow scientists and medical professionals to investigate RA pathology with more precision than conventional radiography by detecting synovitis, which is believed to be an early event in RA. Current assessments of synovitis using MRI involve the semiquantitative RA MRI scoring (RAMRIS) method, which has shown variable reliability in previous studies. The principle objectives of this study were to investigate whether a quantitative manual segmentation method could serve as an outcome measure for the assessment of synovitis by analyzing high field 3 Tesla (3T) MRI wrist images from early and established RA patients. The results showed that manual segmentation at 3T can offer a valid and reliable measurement of synovitis. However, in terms of efficiency, this method may be best used in clinical settings as a reference to which other outcome measures are compared.