Liesbeth Eloot

Bio: Liesbeth Eloot is an academic researcher from Ghent University. The author has contributed to research in topics: Imaging phantom & Imaging technology. The author has an hindex of 5, co-authored 9 publications receiving 75 citations.

Novel X-ray imaging technology enables significant patient dose reduction in interventional cardiology while maintaining diagnostic image quality.

Abstract: Objectives The purpose of this study was to quantify the reduction in patient radiation dose during coronary angiography (CA) by a new X-ray technology, and to assess its impact on diagnostic image quality. Background Recently, a novel X-ray imaging technology has become available for interventional cardiology, using advanced image processing and an optimized acquisition chain for radiation dose reduction. Methods 70 adult patients were randomly assigned to a reference X-ray system or the novel X-ray system. Patient demographics were registered and exposure parameters were recorded for each radiation event. Clinical image quality was assessed for both patient groups. Results With the same angiographic technique and a comparable patient population, the new imaging technology was associated with a 75% reduction in total kerma-area product (KAP) value (decrease from 47 Gycm2 to 12 Gycm2, P < 0.001). Clinical image quality showed an equivalent detail and contrast for both imaging systems. On the other hand, the subjective appreciation of noise was more apparent in images of the new image processing system, acquired at lower doses, compared to the reference system. However, the higher noise content did not affect the overall image quality score, which was adequate for diagnosis in both systems. Conclusions For the first time, we present a new X-ray imaging technology, combining advanced noise reduction algorithms and an optimized acquisition chain, which reduces patient radiation dose in CA drastically (75%), while maintaining diagnostic image quality. Use of this technology may further improve the radiation safety of cardiac angiography and interventions. © 2015 Wiley Periodicals, Inc.

Dealing with pregnancy in radiology: a thin line between science, social and regulatory aspects.

Abstract: The participation of pregnant women in radiology can be an emotional experience. The word "radiation" understandably invokes fear and uncertainty. Irradiation of a foetus should be avoided whenever possible. However, radiological examinations of pregnant women are often justified and unintended exposures do occur. Also pregnant radiology staff may remain working in the department. Lack of knowledge about the effects of both ionising (X-rays) and non-ionising (MRI) radiation is responsible for anxiety of patients and workers. If foetal exposures occur, they must be quantitatively evaluated and the risk put into perspective. This paper is intended to inform radiology managers, radiologists, technologists and referring clinicians in their management with pregnant patients and co-workers. The paper describes conceptus doses for both patient and worker that are associated with radiology practice, reviews the risks and effects of in utero irradiation, and discusses current national policies, international guidelines and practical aspects.

Three-dimensional rotational X-ray acquisition technique is reducing patients' cancer risk in coronary angiography.

Abstract: Objectives The purpose of this study was to assess patient-specific organ doses and cancer risk with 3D-rotational acquisitions versus the current standard of multiple single-plane coronary angiography (CA). Background Catheter-based CA remains one of the most commonly performed diagnostic invasive procedures delivering a relatively high radiation dose to the patient. With the introduction of flat-panel technology, three-dimensional rotational angiography became an alternative for the conventional two-dimensional angiography. However, limited information is available on the difference in patient radiation exposure with both acquisition techniques. Methods Eighty adult patients (45 males, age 38–93 years) were randomly assigned to the rotational or standard angiography group. Exposure parameters were registered and skin dose distribution was measured during the procedure. Patient-specific organ doses and related cancer risks were assessed with dedicated software. Results Rotational angiograms were associated with 33% lower KAP-values (decrease from 49.99 Gycm2 to 33.37 Gycm2, P < 0.001). A significant (P < 0.001) lower peak skin dose was measured with rotational acquisitions (80 mGy, median) versus planar imaging (172 mGy, median). Moreover, the skin dose was smoothed over the whole chest of the patient. Contrast medium consumption decreased from 104 mL to 73 mL (P < 0.001) with the use of 3D-imaging. The reduction in radiation exposure resulted in a corresponding decrease of organ doses. The latter contributed to an overall cancer risk reduction of 21% for males and 50% for females. Conclusions The current study demonstrates that in CA radiation risk reduction is feasible by using a rotational acquisition technique.© 2013 Wiley Periodicals, Inc.

Evaluation of patient and staff exposure with state of the art X-ray technology in cardiac catheterization: A randomized controlled trial.

Abstract: INTRODUCTION Cardiac catheterization procedures result in high patient radiation exposure and corresponding staff doses are reported to be among the highest for medical staff The purpose of current randomized controlled study was to quantify the potential radiation dose reduction for both patient and staff, enabled by recent X-ray technology This technology is equipped with advanced image processing algorithms, real-time dose monitoring, and an acquisition chain optimized for cardiac catheterization applications METHODS A total of 122 adult patients were randomly assigned to one of two cath labs, either the reference X-ray modality (Allura Xper FD10, Philips Healthcare, the Netherlands) or the new X-ray system (AlluraClarity FD20/10 Philips Healthcare, the Netherlands) Exposure parameters and staff dosimeter readings were recorded for each exposure Technical measurements were performed to define the radiation scatter behavior RESULTS With the newer equipment, patient radiation dose is reduced (as total dose-area product) by 67% based on geometric means with 95%CI of 53%, 77% for diagnostic and interventional procedures The C-arm and leg dosimeter readings were both reduced with 65% (P < 0001), while for the collar and chest dosimeter readings no statistically significant reduction was noticed CONCLUSION The new x-ray and image processing technology, significantly reduces patient dose in coronary angiographies, and PCIs by 67% In general, scatter dose was also reduced, yet for some dosimeters the reduction was limited and not statistically significant This study clearly indicates that the scatter behavior is highly dependent on C-arm rotation, operator movement and height, dosimeter position, beam filtration, clinical procedure type and system geometry

Quality control of micro-computed tomography systems

Abstract: The rapid proliferation of micro-computed tomography (micro-CT) scanners in preclinical small animal studies has created a need for a method on scanner performance evaluation and scan parameter optimisation. The purpose of this study was to investigate the performance of the scanner with a dedicated micro-CT phantom. The phantom was developed with different independent sections that allow for measurement of major scanner characteristics such as uniformity, linearity, contrast response, dosimetry and resolution. The results of a thorough investigation are discussed.

Occupational radiation exposure in the electrophysiology laboratory with a focus on personnel with reproductive potential and during pregnancy: A European Heart Rhythm Association (EHRA) consensus document endorsed by the Heart Rhythm Society (HRS)

Abstract: Occupational radiation exposure in the electrophysiology laboratory with a focus on personnel with reproductive potential and during pregnancy : A European Heart Rhythm Association (EHRA) consensus document endorsed by the Heart Rhythm Society (HRS)

Micro-CT for Anatomic Referencing in PET and SPECT: Radiation Dose, Biologic Damage, and Image Quality

Abstract: CT is widely used for anatomic referencing of PET and SPECT images of small animals but requires sufficiently high radiation doses capable of causing significant DNA damage. Therefore, we described the relationship between radiation dose, biologic damage, and image quality to determine whether CT can be used without significantly compromising radiotherapy and tumor development studies. Methods: The CT dose index generated by the nanoSPECT/CT system was compared with measurements using EBT2 gafchromic film. The effects of micro-CT were evaluated in 2 mouse strains that differ in sensitivity to radiation. γH2AX foci analysis to determine leukocyte, liver, and jejunum DNA damage and hematoxylin and eosin staining to investigate macroscopic jejunum damage were performed. Signal-to-noise ratio, contrast-to-noise ratio, and scanner linearity were determined to assess image quality. Results: For the standard settings, that is, as set by the manufacturers, EBT2 gafchromic film dosimetry showed that the nanoSPECT/CT system underestimated the absorbed dose. Moreover, significant doses were obtained, resulting in a significant increase in γH2AX formation in leukocytes, liver, and jejunum 40 min after CT, using preset parameters when compared with nonimaged controls. The jejenum response was more pronounced for the more radiosensitive strain. In contrast to leukocytes, the liver and jejunum still showed evidence of DNA damage 3 d after CT. Contrast-to-noise ratio, signal-to-noise ratio, and scanner linearity were sufficient to allow for anatomic referencing for both imaging protocols tested. Conclusion: Anatomic reference images can be produced with no observable DNA damage or compromising image quality using low radiographic voltage, flux, and duration.

Mapping primary gyrogenesis during fetal development in primate brains: High-resolution in utero structural MRI of fetal brain development in pregnant baboons

Abstract: The global and regional changes in the fetal cerebral cortex in primates were mapped during primary gyrification (PG; weeks 17-25 of 26 weeks total gestation) Studying pregnant baboons using high-resolution MRI in utero, measurements included cerebral volume, cortical surface area, gyrification index and length and depth of ten primary cortical sulci Seven normally developing fetuses were imaged in two animals longitudinally and sequentially We compared these results to those on PG that from the ferret studies and analyzed them in the context of our recent studies of phylogenetics of cerebral gyrification We observed that in both primates and non-primates, the cerebrum undergoes a very rapid transformation into the gyrencephalic state, subsequently accompanied by an accelerated growth in brain volume and cortical surface area However, PG trends in baboons exhibited some critical differences from those observed in ferrets For example, in baboons, the growth along the long (length) axis of cortical sulci was unrelated to the growth along the short (depth) axis and far outpaced it Additionally, the correlation between the rate of growth along the short sulcal axis and heritability of sulcal depth was negative and approached significance (r=-060;p<10), while the same trend for long axis was positive and not significant (p=03;p=040) These findings, in an animal that shares a highly orchestrated pattern of PG with humans, suggest that ontogenic processes that influence changes in sulcal length and depth are diverse and possibly driven by different factors in primates than in non-primates

Viewdex: a status report.

Abstract: ViewDEX (Viewer for Digital Evaluation of X-ray images) is an image viewer and task manager suitable for research and optimisation tasks in medical imaging. The software has undergone continuous development during more than a decade and has during this time period been used in numerous studies. ViewDEX is DICOM compatible, and the features of the interface (tasks, image handling and functionality) are general and flexible. The set-up of a study is determined by altering properties in a text-editable file, enabling easy and flexible configuration. ViewDEX is developed in Java and can run from any disc area connected to a computer. It is free to use for non-commercial purposes and can be downloaded from http://www.vgregion.se/sas/viewdex The purposes of the present article are to give a short overview of the development of ViewDEX and to describe recent updates of the software. In addition, a description on how to configure a viewing session in ViewDEX is provided.