Usefulness of Digital Velcro Crackles Detection in Identification of Interstitial Lung Disease in Patients With Connective Tissue Diseases
Andreina MANFREDI1, Giulia CASSONE2, Caterina VACCHI2, Fabrizio PANCALDI3, Giovanni Della CASA4, Stefania CERRI5, Lisa De PASQUALE1, Fabrizio LUPPI6, Carlo SALVARANI7, Marco SEBASTIANI1
1Rheumatology Unit, University of Modena and Reggio Emilia, Modena, Italy
2Department of Sciences and Methods For Engineering, University of Modena and Reggio Emilia, Modena, Italy
3Radiology Unit, University of Modena and Reggio Emilia, Modena, Italy
4Respiratory Unit, University of Modena and Reggio Emilia, Modena, Italy
5Respiratory Unit, University of Milan-bicocca, San Gerardo Hospital, Monza, Italy
6Rheumatology Unit, Irccs Arcispedale Santa Maria Nuova, Azienda Unità Sanitaria Locale-irccs Di Reggio Emilia, Reggio Emilia, Italy
7PhD Program In Clinical and Experimental Medicine, University of Modena and Reggio Emilia, Modena, Italy
Keywords: Connective tissue diseases, diagnosis, interstitial lung disease, screening, VECTOR, velcro crackles
Objectives: This study aims to evaluate the diagnostic accuracy of the VECTOR software in patients with connective tissue diseases (CTDs), compared with the reference standard of high-resolution computed tomography (HRCT).
Patients and methods: The study included 98 consecutive patients of CTD (24 males, 74 females; median age 66 years; range, 24 to 85 years) with a recent HRCT. Patients were evaluated in a blindly manner by VECTOR and the results obtained by the algorithm were compared with the presence of interstitial lung disease (ILD) according to HRCT.
Results: Interstitial lung disease was detected in 42.8% of subjects. VECTOR correctly classified 81/98 patients, with a diagnostic accuracy of 82.6%; sensitivity and specificity were 88.1% and 78.6%, respectively. Only 5/42 patients with ILD were not correctly classified by VECTOR, while false positive cases were 21.4%. No significant differences were observed according to the radiologic pattern of ILD.
Conclusion: VECTOR showed high sensitivity, specificity and diagnostic accuracy, allowing selecting patients to be investigated with HRCT. The relatively high frequency rate of false positive results is acceptable if compared with the lack of effective screening methods for this complication of CTDs.