Visual versus automatic ultrasound scoring of lung B-lines: reliability and consistency between systems

Abstract

Aims: To evaluate the agreement between a visual and an automatic counting system of lung B-lines by ultrasound (US) as well as to test the inter- and intra-observer reliability of both systems in patients with lung diseases.

Material and methods: We included four patients with different lung conditions. Four ultrasonographers expert in lung US blindly, independently and consecutively performed, in two rounds, a US B-mode assessment of 8 lung intercostal spaces of each patient. Each US assessment consisted of a visual and an automatic counting of B-lines.

Results: Agreement between visual and automatic counting of B-lines was good to excellent [intraclass correlation coefficient (ICC) 0.79-0.84, p<0.001]. Intra-observer reliability was good to excellent [ICC 0.62-0.99, p<0.001] except for one investigator in whom it was close to moderate for the automatic system [ICC 0.49, p<0.05]. Inter-observer reliability was excellent for both systems in both rounds [ICC 0.86-0.90, p<0.001].

Conclusions: US automatic counting was consistent with US visual counting of lung B-lines, as performed by experts in the field. Both systems showed a high intra- and interobserver reliability.