Visual grading analysis of digital neonatal chest phantom X-ray images: Impact of detector type, dose and image processing on image quality

ObjectivesTo evaluate the impact of digital detector, dose level and post-processing on neonatal chest phantom X-ray image quality (IQ).MethodsA neonatal phantom was imaged using four different detectors: a CR powder phosphor (PIP), a CR needle phosphor (NIP) and two wireless CsI DR detectors (DXD and DRX). Five different dose levels were studied for each detector and two post-processing algorithms evaluated for each vendor. Three paediatric radiologists scored the images using European quality criteria plus additional questions on vascular lines, noise and disease simulation. Visual grading characteristics and ordinal regression statistics were used to evaluate the effect of detector type, post-processing and dose on VGA score (VGAS).ResultsNo significant differences were found between the NIP, DXD and CRX detectors (p>0.05) whereas the PIP detector had significantly lower VGAS (p< 0.0001). Processing did not influence VGAS (p=0.819). Increasing dose resulted in significantly higher VGAS (p<0.0001). Visual grading analysis (VGA) identified a detector air kerma/image (DAK/image) of ~2.4 μGy as an ideal working point for NIP, DXD and DRX detectors.ConclusionsVGAS tracked IQ differences between detectors and dose levels but not image post-processing changes. VGA showed a DAK/image value above which perceived IQ did not improve, potentially useful for commissioning.Key points• A VGA study detects IQ differences between detectors and dose levels.• The NIP detector matched the VGAS of the CsI DR detectors.• VGA data are useful in setting initial detector air kerma level.• Differences in NNPS were consistent with changes in VGAS.

[1]  Patrik Sund,et al.  Comparison of visual grading analysis and determination of detective quantum efficiency for evaluating system performance in digital chest radiography , 2004, European Radiology.

[2]  E. Siegel,et al.  Continuing challenges in defining image quality , 2011, Pediatric Radiology.

[3]  R. Nowotny,et al.  Diagnostic reference levels in pediatric radiology in Austria , 2010, European Radiology.

[4]  Magnus Båth,et al.  Evaluating imaging systems: practical applications. , 2010, Radiation protection dosimetry.

[5]  Mathias Prokop,et al.  Digital chest radiography: an update on modern technology, dose containment and control of image quality , 2008, European Radiology.

[6]  M Alvarez,et al.  Association between subjective evaluation and physical parameters for radiographic images optimization. , 2016, Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics.

[7]  E. Ludewig,et al.  [Assessment of clinical image quality in feline chest radiography with a needle-image plate (NIP) storage phosphor system--an approach to the evaluation of image quality in neonatal radiography]. , 2010, RoFo : Fortschritte auf dem Gebiete der Rontgenstrahlen und der Nuklearmedizin.

[8]  B. Wall,et al.  Reference Doses and Patient Size in Paediatric Radiology , 2001 .

[9]  Ehsan Samei,et al.  An exposure indicator for digital radiography: AAPM Task Group 116 (executive summary). , 2009, Medical physics.

[10]  H. Jun,et al.  Reduced radiation dose and improved image quality using a mini mobile digital imaging system in a neonatal intensive care unit. , 2017, Clinical imaging.

[11]  O. Smedby,et al.  Quantifying the potential for dose reduction with visual grading regression. , 2012, The British journal of radiology.

[12]  Anita Conradie,et al.  Evaluating the effect of reduced entrance surface dose on neonatal chest imaging using subjective image quality evaluation. , 2015, Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics.

[13]  L. Martin,et al.  Paediatric x-ray radiation dose reduction and image quality analysis , 2013, Journal of radiological protection : official journal of the Society for Radiological Protection.

[14]  Hilde Bosmans,et al.  Validation of an image simulation technique for two computed radiography systems: an application to neonatal imaging. , 2010, Medical physics.

[15]  F. Vanhavere,et al.  Radiation dose to premature new-borns in the Belgian neonatal intensive care units. , 2014, Radiation protection dosimetry.

[16]  M. Ruschin,et al.  A software tool for increased efficiency in observer performance studies in radiology. , 2005, Radiation protection dosimetry.

[17]  P. Khong,et al.  Radiological Protection in Paediatric Diagnostic and Interventional Radiology , 2012 .

[18]  H Järvinen,et al.  Diagnostic reference levels for thorax X-ray examinations of paediatric patients. , 2007, The British journal of radiology.

[19]  Luís Lança,et al.  Digital radiography detectors – A technical overview: Part 2 , 2009 .

[20]  M J Tapiovaara,et al.  Review of relationships between physical measurements and user evaluation of image quality. , 2008, Radiation protection dosimetry.

[21]  Quentin T Moore,et al.  Image gently campaign back to basics initiative: ten steps to help manage radiation dose in pediatric digital radiography. , 2013, AJR. American journal of roentgenology.

[22]  Magnus Båth,et al.  VIEWDEX: an efficient and easy-to-use software for observer performance studies. , 2010, Radiation protection dosimetry.

[23]  William F. Sensakovic,et al.  Image quality and dose differences caused by vendor-specific image processing of neonatal radiographs , 2016, Pediatric Radiology.

[24]  E. Guibelalde,et al.  Physical image quality comparison of four types of digital detector for chest radiology. , 2008, Radiation protection dosimetry.

[25]  M Båth,et al.  Visual grading characteristics (VGC) analysis: a non-parametric rank-invariant statistical method for image quality evaluation. , 2007, The British journal of radiology.

[26]  Amy Berrington de González,et al.  Risk of cancer from diagnostic X-rays: estimates for the UK and 14 other countries , 2004, The Lancet.

[27]  C. Armpilia,et al.  Radiation dose quantities and risk in neonates in a special care baby unit. , 2002, The British journal of radiology.

[28]  D. Manke,et al.  A MONTE-CARLO SIMULATION FRAMEWORK FOR JOINT OPTIMISATION OF IMAGE QUALITY AND PATIENT DOSE IN DIGITAL PAEDIATRIC RADIOGRAPHY. , 2016, Radiation protection dosimetry.

[29]  Michael Sandborg,et al.  Comparison of clinical and physical measures of image quality in chest and pelvis computed radiography at different tube voltages. , 2006, Medical physics.

[30]  S. Don Pediatric digital radiography summit overview: state of confusion , 2011, Pediatric Radiology.

[31]  Michael Sandborg,et al.  CLINICAL AUDIT OF IMAGE QUALITY IN RADIOLOGY USING VISUAL GRADING CHARACTERISTICS ANALYSIS. , 2016, Radiation protection dosimetry.

[32]  Martin Spahn,et al.  Flat detectors and their clinical applications , 2005, European Radiology.

[33]  Mark F. McEntee,et al.  Visual grading characteristics and ordinal regression analysis during optimisation of CT head examinations , 2014, Insights into Imaging.

[34]  H. Bosmans,et al.  Technical characterization of five x-ray detectors for paediatric radiography applications. , 2017, Physics in medicine and biology.