Neonatal chest radiography - Comparing image quality and dose for contact-techniques vs. under-tray techniques

Abstract

Chest radiography is the primary and most important diagnostic study in the evaluation of neonates, due to life threating conditions. Neonatal chest images can be made using either contact-techniques or under-tray techniques, which one is superior in respect to doses and image quality? A range of exposure settings were made using a neonate phantom, and the same settings also for spatial resolution measurements. Visual scores were rated for spatial resolution tests, and for clinical phantom images rating present and absent pneumothorax. Entrance surface dose were below the European guidelines for certain exposure settings. The higher the dose, the less are images degraded by noise. The range of kV which is appropriate for the neonates is yet to be determined, though. The quality of the whole imaging chain interacts in a decision. Noise should be lowered whenever possible. Visual scores among two readers were close to each other's, both in spatial resolution, and also in correct diagnostics in relation to noise magnitude, however 1/3 of the images illustrating pneumothorax were ignored. Exposure settings should probably not be equal for the contact and under-tray techniques. There were a tiny decrease in sharpness combined with an increased noise (average 20%) noted in the radiographs obtained from the under tray techniques compared with the contact techniques. Contact techniques were found being superior.