Possible Role of Chest Ultrasonography for the Evaluation of Peripheral Fibrotic Pulmonary Changes in Patients Affected by Idiopathic Pulmonary Fibrosis—Pilot Case Series

Abstract

Lung ultrasonography (LUS) provides an estimation of peripheral airspace (PAS) geometry of the lung. Altered PAS produces sonographic interstitial syndrome (SIS). Idiopathic pulmonary fibrosis (IPF) involves peripheral lung with altered PAS. The aim of the study is to correlate echographic patterns with peripheral fibrotic changes on high-resolution Chest CT scan (HRCT). Patients underwent LUS and HRCT on the same date. Four LUS patterns were described: (1) near normal; (2) SIS with predominance of reverberant artifacts; (3) SIS with vertical predominance; (4) white lung. Four HRCT grades of peripheral fibrotic infiltrates were reported: grade 1 mild; grade 2 moderate; grade 3 severe; grade 4 massive or honeycomb. LUS pattern 1 was indicative of mild to moderate fibrotic alterations in 100% of cases. LUS pattern 2 matched with HRCT grade 2 in 24 out of 30 cases (77%). Huge discordance in four cases because of large honeycomb cysts. LUS pattern 3 was indicative of severe to massive alterations in 100% of cases. LUS pattern 4 showed a heterogeneous distribution of HRCT grades, severe changes, and ground glass opacities (GGO). This preliminary work demonstrates some level of agreement between LUS patterns and HRCT grades. Limitations and methodological issues have been shown to support subsequent studies of agreement.

Chest ultrasound findings in usual interstitial pneumonia patterns: a pilot study

“…As opposed to UIP pattern, no specific interstitial pattern in HRCT is shown as prominent areas of ground glass opacity [21]. Few studies proposed the hypothesis that white lung in chest u/s can be caused by the presence of ground glass opacity in HRCT [18,19]. In our study, ground glass opacities were not associated with white lung in chest u/s.…”

“…This finding needs to be explored in further studies with more attention to the inter-observer correlation to limit the operator's bias of subjectivity. Smaghessi et al [18] tried to correlate u/s patterns with peripheral parenchymal fibrotic changes in HRCT for patients affected by IPF, demonstrating some level of agreement between u/s patterns and HRCT grades of peripheral fibrotic alterations. According to these findings, we may consider chest u/s as a possible relevant tool to highlight the evolution in IPF.…”

“…Indeed, in the recent INBUILD trial [22] that evaluated the safety and efficacy of nintedanib in patients with progressive fibrosing ILD, the authors found that patients who received nintedanib had a slower rate of progression, independent of the fibrotic pattern on HRCT. Chest u/s may not be able to distinguish the various IPF patterns, but it might be able to identify patients with progression to honeycombing [18,23] and therefore be an interesting tool in the patient's treatment strategy.…”

“…Manolescu and associates [17] showed that B lines and the average thickness of the pleural line are highly and positively correlated with HRCT findings, forced vital capacity (FVC) and DLCO. Smargassiassi and colleagues [18], demonstrated some level of agreement between chest u/s patterns and HRCT grades of peripheral fibrotic changes. In a small cohort, Manolescu et al [19] suggested that chest u/s could distinguish lung interstitial patterns (UIP, possible UIP, non-specific interstitial pneumonia -NSIP).…”

State of the Art in Lung Ultrasound, Shifting from Qualitative to Quantitative Analyses

“…Because the necessity to develop acquisition strategies specifically designed for lung has been highlighted not only by clinicians, but also by researchers with technical backgrounds, the development of quantitative approaches could represent the future of LUS (Demi et al 2014). The evaluation of correlations between anatomical findings observed with standard imaging modalities (e.g., chest x-rays and CT), which are linked to histological observations, and LUS patterns (Soldati et al 2016(Soldati et al , 2017Smargiassi et al 2019Smargiassi et al , 2020a should represent an important starting point for developing ultrasound approaches specifically dedicated to lungs. This comparison could indeed allow researchers to study the link between the air spaces' (alveoli) resizing and spatial reorganization, as caused by different pathologies, and the quantifiable features of LUS artifacts (Soldati et al 2019(Soldati et al , 2020b.…”