Assessment of interstitial lung disease in systemic sclerosis using the quantitative CT algorithm CALIPER

Area of Science:

• Radiology
• Pulmonary Medicine
• Rheumatology

Background:

• Interstitial lung disease (ILD) is a significant cause of mortality in systemic sclerosis (SSc).
• Accurate characterization and quantification of SSc-ILD are crucial for patient management.
• High-resolution computed tomography (HRCT) is a key imaging modality for assessing lung involvement in SSc.

Purpose of the Study:

• To characterize and quantify SSc-ILD using Computer-Aided Lung Informatics for Pathology Evaluation and Rating (CALIPER).
• To determine which radiological patterns on HRCT predict lung function decline over 12 months.
• To evaluate the utility of CALIPER in assessing SSc-ILD progression and its correlation with pulmonary function tests (PFTs).

Main Methods:

• A prospective study involving 66 SSc patients who underwent baseline HRCT.
• CALIPER software was used to classify lung parenchyma into normal, ground glass, reticular, and honeycombing patterns.
• Pulmonary function tests (PFTs), including FEV1, FVC, and DLCO, were performed at baseline and 12-month follow-up.

Main Results:

• At baseline, the reticular pattern showed a negative correlation with FEV1, FVC, and DLCO.
• At 12-month follow-up, the ground glass pattern percentage positively correlated with DLCO reduction.
• ROC analysis indicated that the ground glass score is a significant predictor of DLCO worsening (decrease >10%), with a cutoff of ≥4.5 indicating a 6.8-fold increased risk.

Conclusions:

• CALIPER is a valuable tool for quantifying lung damage in SSc-ILD.
• The ground glass pattern on HRCT, as assessed by CALIPER, can predict future decline in DLCO.
• Further research with larger cohorts is warranted to validate these findings and establish CALIPER's role in routine SSc-ILD monitoring.