Abstract: 【Abstract】 Objective To analyze clinical, laboratory and imaging characteristics of different subtypes of linear morphea （LM）, and to propose an appropriate approach to the diagnosis and severity assessment of LM. Methods Clinical data were collected from patients with clinically and/or pathologically confirmed LM in Department of Dermatology, West China Hospital, Sichuan University from January 2018 to December 2019, and retrospectively analyzed. Results A total of 107 patients with LM were enrolled into this study, including 63 with LM of the limbs/trunk , 22 with morphea en coup de sabre, 11 with progressive hemifacial atrophy and 11 with eosinophilic fasciitis. Disease severity was evaluated by using the modified localized scleroderma skin severity index （mLoSSI） and localized scleroderma skin damage index （LoSDI） scores in 88 patients, with the mLoSSI scores ranging from 0 to 51 points, and the LoSDI scores ranging from 0 to 40 points. Routine blood examination of 10 patients with eosinophilic fasciitis showed increased eosinophil counts in 4 patients. Thirteen （14.8%） of 88 patients with LM were positive for antinuclear antibody, with titers of ≥ 1∶320. Magnetic resonance imaging （MRI） examination showed ipsilateral cerebral hemisphere atrophy and contralateral white matter hyperintensity on T2-weighted images in 2 out of 4 patients with progressive hemifacial atrophy, myofascial thickening in 26 out of 28 patients with LM of the limbs/trunk （92.9%）, subcutaneous septal and myofascial thickening in all 11 patients with eosinophilic fasciitis. Conclusions The preliminary assessment of disease activity, severity and prognosis of LM can be made by mLoSSI and LoSDI. MRI examination is recommended for patients with clinical signs of involvement of subcutaneous structures.

Key words: Linear morphea, Linear morphea of the limbs/trunk, Morphea en coup de sabre, Progressive hemifacial atrophy, Eosinophilic fasciitis