MRI Quantification of Pulmonary Fibrosis in Scleroderma Patients by Using Elastic Registration Method: Feasibility Study

Assessment of pulmonary fibrosis is currently based on high-resolution CT (HRCT) and pulmonary function tests (PFT) such as forced vital capacity, (FVC) and carbon monoxide diffusion (DLCO). These techniques allow a semi-quantitative analysis of the pulmonary disease but are imperfect. The mains weaknesses are the lack of reproducibility, the limited sensitivity and for CT the resulting radiation dose.

Recent advances in MRI sequences allow exploring the lung parenchyma with millimeter slice thickness. Development of computer-assisted post-processing such as elastic registration opens new perspectives in the functional study of the lung parenchyma, especially the analysis of its deformation during the respiratory cycle and therefore of its elasticity.

Pulmonary involvement in scleroderma is present in 70 to 100% of patients and is the leading cause of death. Initial assessment of pulmonary involvement and follow-up are important for therapeutic decisions and patient prognosis. Quantitative analysis should be developed to reliably evaluate pulmonary fibrosis and increase the reproducibility.

The purpose of our study is to evaluate the feasibility of quantifying pulmonary fibrosis by successively performing full inspiration then full expiration volumetric MR acquisitions using a VIBE - Volumetric Interpolated Breath-hold examination sequence. Post processing of the 2 volumes using elastic registration is performed to evaluate pulmonary deformation in the normal and fibrotic lung areas, hypothesizing that it would be different.