SAT0406 Quantification of interstitial pulmonary fibrosis in systemic sclerosis using an open-source dicom viewer software (OSIRIX)

Abstract

Background Interstitial pulmonary fibrosis (IPF) is a frequent manifestation in patients with systemic sclerosis (SSc). The severity of lung involvement may vary considerably depending on the underlying disease and it can be often the cause of death of these patients (1). Currently chest high resolution computed tomography (HRCT) is considered the “gold-standard” for the diagnosis and disease activity monitoring of IPF (2). The recent availability of open sources DICOM viewer softwares such as OsiriX (3) opens up a new research area for the rheumatologist to assess the IPF. Objectives To investigate the correlation between a open source (OsiriX) software and HRCT findings in the assessment of IPF in patients with SSc. Methods Sixty two patients with diagnosis of SSc were enrolled. All patients showed an IPF at HRCT which has been interpreted by two expert radiologist. Spirometric pulmonary function tests and DLco were also performed. Both radiologist indipendently performed an analysis of the HRCT findings of all patients in order to score the IPF. Successively they reached an agreement by a discussion to obtain a consensus for a single score. Afterwards, an experienced OsiriX user rheumatologist, independently and blinded to radiologists’ scoring, quantified the overall extent of IPF in all patients using Osirix, which is a multidimensional DICOM viewer software designed to display, interpret and analyze large sets of multidimensional and multimodality images with many tools that allow the user to perform post-processing algorithms. These results were compared with those obtained by the lectures of the radiologists. Results A total of 62 SSc patients were assessed. A highly significant correlation between radiologists’ scoring and OsiriX HRCT quantitative assessment of IPF was found (p≤0.0001). In particular there was a significant correlation between quantitative evaluation and visual scoring stratified according to overall extension and fibrosis (both p≤0.0001). No correlation was found between quantitative assessment and DLco values (p=0.73). Conclusions Our results provide a new working hypothesis in favour of the utility of OsiriX in perfoming an objective IPF evaluation which could be very helpful in assessing and monitoring SSc patients. References Tyndall et al. Causes and risk factors for death in systemic sclerosis: a study from the EULAR Scleroderma Trials and Research (EUSTAR) database. Ann Rheum Dis 2010; 69 (10):1809–15. Wells. High-resolution computed tomography and scleroderma lung disease. Rheumatology (Oxford) 2008; 47 (Suppl 5):v59-61. Rosset et al. OsiriX: an open-source software for navigating in multidimensional DICOM images. J Digit Imaging 2004;17 (3): 205-16. Disclosure of Interest None Declared