Neonatal Chest Phantom for Computed Radiography Testing

DESCRIPTION (provided by applicant): The principle of ALARA (as low as reasonably achievable) has been developed to reduce the risk of induced malignancy from radiation exposure, In practice this requires a rigorous quality control process for clinical operations in radiology. Currently, a critical tool (a radiographic test phantom) needed for quality control is not commercially available for computed radiology and digital radiography. The application's long-term goal is to develop a new class of phantoms and objective system performance tools for use in digital radiographic systems. These devices will be used to address emerging needs in computed radiography and digital radiography. These needs include (1) quality control procedures for daily operations, (2) quality assurance methods to evaluate products arid perform acceptance testing, (3) quality assurance methods for optimizing system operating parameters, and (4) development tools for manufacturers to assess new hardware and software products. Because neonatal chest radiography is a technically challenging procedure, with profound radiation dose implications, a prototype neonatal chest phantom was successfully developed in Phase I and is the focal point for Phase II phantom development. The neonatal chest phantom will be developed to simulate the disease states of pneumothorax and hyaline membrane disease. An observer's ability to diagnose these two disease states will test system resolution and noise, respectively. An automated objective system performance tool will also be developed to measure quantifiable parameters, such as resolution (modulation transfer function), noise (noise power spectrum), and detector efficiency (detective quantum efficiency). Phase II has two Specific Aims: 1) Clinical Validation of the Neonatal Chest Phantom in Normal and Disease States; 2) Clinical Validation of the Objective System Performance Tool. Successful neonatal chest phantom design will be determined by the appearance and histogram analysis of images; the attenuation values of anatomic structures; and the diagnostic performances of radiologists for detection of disease states within the phantom. Successful objective system performance tool design will be determined by agreement with established methods of calculating quantitative parameters. The commercial applications are driven by the phantom's clinical significance, which is to assure optimal equipment performance and minimize x-ray exposure, thereby reducing the concomitant risk of induced malignancy to neonates.