" Synthetic" Comets: A New Look at Lung Sonography

Gino Soldati, Valeria Giunta, Sara Sher, Francesca Melosi, Claudia Dini

Research output: Contribution to journalArticlepeer-review


Ultrasound interstitial syndrome is an echographic pattern of the lung characterized by the presence of multiple acoustic artifacts called " comets" or B-lines. It correlates to increase in extravascular lung water and to interstitial lung disease. From the physical and genetic point of view, the characteristics and the entity of this correlation have not yet been studied. The purpose of this study was to extrapolate past observations and demonstrate how comets or B-lines are artifactual images whose formation is linked to ultrasound interactions on discretely aerated tissues of variable density. Echographic comets were studied by scanning a wet synthetic, partially aerated polyurethane sponge (phantom). Density of the phantom in different drying phases was measured and correlated to the presence of echographic artifacts. Artifacts (comets) showed a different concentration from a completely white artifactual field to presence of rare comets. Their density correlates with porosity and geometry of the phantom. In our opinion, comets represent superficial, artifactual, density and geometry correlated phenomenon due to the acoustic permeability of a broken (collapsed) specular reflector, normally present when the phantom is dry.

Original languageEnglish
Pages (from-to)1762-1770
Number of pages9
JournalUltrasound in Medicine and Biology
Issue number11
Publication statusPublished - Nov 2011


  • Artifact
  • Diagnosis
  • Lung
  • Ultrasound

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Radiological and Ultrasound Technology
  • Biophysics


Dive into the research topics of '" Synthetic" Comets: A New Look at Lung Sonography'. Together they form a unique fingerprint.

Cite this