Usefulness of Hrct in Diagnosis and Follow up of Pulmonary Involvement in Systemic Sclerosis

ABSTRACT PURPOSE To assess the usefulness of HRCT in diagnosis and follow up of pulmonary involvement in systemic sclerosis. MATERIALS and METHODS A total of 159 patients with systemic sclerosis, without overlap features, were studied. Sequential HRCT evaluation was realized in 138 patients. Semiquantification of HRCT findings was based on the grading systems introduced by Wells et al and Warrick et al. Follow up studies included semiquantitative evaluation of change in the extent and coarseness of disease at anatomically comparable sections. The database also included the results of pulmonary function tests and clinical information acquired during follow up of patients. RESULTS An HRCT score of 7 would be required to consider HRCT abnormalities in systemic sclerosis as predictive of functional impairment. The rates of progression in HRCT findings in diffuse scleroderma patients were higher than in acroscleroderma patients. A statistically significant inverse correlation was found between the score of change in the extent and coarseness of disease and the percentage of changes in DLCO (rs=-0,33,p=0,01), FVC (rs=-0,28, p=0,03) and TLC (rs=-0,34, p=0,02) values, after the first sequential imaging evaluation. Mixed effects models revealed a significant inverse correlation during the entire follow up period between the indices of change in imaging findings and the percentages of change in DLCO (Β=-2,35, p=0,005) and TLC values (Β=2,29, p=0,01). Careful HRCT quantification of imaging progression during short term follow up could have prognostic significance regarding changes in functional parameters, with diagnostic accuracy that exceeds 70%. CONLUSIONS During follow up the change in the extent and coarseness of disease on HRCT is correlated with the correspondent changes in functional indices and could also have prognostic significance regarding functional impairment.