Improvement of image quality applying iterative scatter correction for grid-less skeletal radiography in trauma room setting

Background Iterative reconstruction is well established for CT. Plain radiography also takes advantage of iterative algorithms to reduce scatter radiation and improve image quality. First applications have been described for bedside chest X-ray. A recent experimental approach also provided proof of principle for skeletal imaging. Purpose To examine clinical applicability of iterative scatter correction for skeletal imaging in the trauma setting. Material and Methods In this retrospective single-center study, 209 grid-less radiographs were routinely acquired in the trauma room for 12 months, with imaging of the chest (n = 31), knee (n = 111), pelvis (n = 14), shoulder (n = 24), and other regions close to the trunk (n = 29). Radiographs were postprocessed with iterative scatter correction, doubling the number of images. The radiographs were then independently evaluated by three radiologists and three surgeons. A five-step rating scale and visual grading characteristics analysis were used. The area under the VGC curve (AUCVGC) quantified differences in image quality. Results Images with iterative scatter correction were generally rated significantly better (AUCVGC = 0.59, P < 0.01). This included both radiologists (AUCVGC = 0.61, P < 0.01) and surgeons (AUCVGC = 0.56, P < 0.01). The image-improving effect was significant for all body regions; in detail: chest (AUCVGC = 0.64, P < 0.01), knee (AUCVGC = 0.61, P < 0.01), pelvis (AUCVGC = 0.60, P = 0.01), shoulder (AUCVGC = 0.59, P = 0.02), and others close to the trunk (AUCVGC = 0.59, P < 0.01). Conclusion Iterative scatter correction improves the image quality of grid-less skeletal radiography in the clinical setting for a wide range of body regions. Therefore, iterative scatter correction may be the future method of choice for free exposure imaging when an anti-scatter grid is omitted due to high risk of tube-detector misalignment.

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Image quality is resilient against tube voltage variations in post-mortem skeletal radiography with a digital flat-panel detector

Scientific Reports ◽

10.1038/s41598-021-87294-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

S. Notohamiprodjo ◽

K. M. Roeper ◽

K. M. Treitl ◽

B. Hoberg ◽

F. Wanninger ◽

...

Keyword(s):

Image Quality ◽

Patient Exposure ◽

Signal To Noise ◽

Flat Panel ◽

Tube Voltage ◽

Low Contrast ◽

Body Regions ◽

Human Cadavers ◽

Skeletal Radiography ◽

Phantom Studies

AbstractIn recent phantom studies low-contrast detectability was shown to be independent from variations in tube voltage in digital radiography (DR) systems. To investigate the transferability to a clinical setting, the lower extremities of human cadavers were exposed at constant detector doses with different tube voltages in a certain range, as proposed in the phantom studies. Three radiologists independently graded different aspects of image quality (IQ) in a comparative analysis. The grades show no correlation between IQ and kV, which means that the readers were not able to recognize a significant IQ difference at different kV. Signal-to-noise and contrast-to-noise ratios showed no significant differences in IQ despite the kV-setting variations. These findings were observed from a limited kV range setting. Higher kV-settings resulted in lowest patient exposure at constant IQ. These results confirm the potential of DR-systems to contribute to standardization of examination protocols comparable to computed tomography. This may prevent the trend to overexpose. Further investigations in other body regions and other DR-systems are encouraged to determine transferability.

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Iterative scatter correction for grid-less skeletal radiography allows improved image quality equal to an antiscatter grid in adjunct with dose reduction: a visual grading study of 20 body donors

Acta Radiologica ◽

10.1177/0284185118796668 ◽

2018 ◽

Vol 60 (6) ◽

pp. 735-741 ◽

Cited By ~ 1

Author(s):

Christoph G Lisson ◽

Catharina S Lisson ◽

Sebastian Kleiner ◽

Marc Regier ◽

Meinrad Beer ◽

...

Keyword(s):

Quality Improvement ◽

Image Quality ◽

Dose Reduction ◽

Scatter Correction ◽

X Rays ◽

Visual Grading ◽

Image Quality Improvement ◽

Skeletal Radiography ◽

A New Technique ◽

Antiscatter Grid

Background Iterative scatter correction (ISC) is a new technique applicable to plain radiography; comparable to iterative reconstruction for computed tomography, it promises dose reduction and image quality improvement. ISC for bedside chest X-rays has been applied and evaluated for some time and has recently been commercially offered for plain skeletal radiography. Purpose To analyze the potential of ISC for plain skeletal radiography with regard to image quality improvement, dose reduction, and replacement for an antiscatter grid. Material and Methods A total of 385 radiographs with different imaging protocols of the pelvis and cervical spine were acquired from 20 body donors. Radiographs were rated by four radiologists. Ratings were analyzed with visual grading characteristics (VGC) analysis. The area under the VGC curve was used as a measure of difference in image quality. Results Without ISC, the grid-less images were rated significantly worse than their grid-based counterparts (0.389, P = 0.005); adding ISC made image quality equal (0.498; P = 0.963). In grid-less imaging, reduction of dose by 50% led to significant image quality impairment (0.415, P = 0.001); this was fully counterbalanced when ISC was added (0.512; P = 0.588). Conclusion ISC for plain skeletal radiography has the ability to replace the antiscatter grid without image quality impairment, to improve image quality in grid-less imaging, and to reduce patient radiation dose by 50% without substantial loss in image quality.

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Fully digital PET is unaffected by any deterioration in TOF resolution and TOF image quality in the wide range of routine PET count rates

EJNMMI Physics ◽

10.1186/s40658-020-00344-5 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Julien Salvadori ◽

Freddy Odille ◽

Gilles Karcher ◽

Pierre-Yves Marie ◽

Laetitia Imbert

Keyword(s):

Image Quality ◽

Dead Time ◽

Silicon Photomultipliers ◽

Timing Resolution ◽

Upper Limits ◽

Wide Range ◽

Pile Up ◽

Digital Pet ◽

Trigger Circuit

Abstract Purpose Digital PET involving silicon photomultipliers (SiPM) provides an enhanced time-of-flight (TOF) resolution as compared with photomultiplier (PMT)-based PET, but also a better prevention of the count-related rises in dead time and pile-up effects mainly due to smaller trigger domains (i.e., the detection surfaces associated with each trigger circuit). This study aimed to determine whether this latter property could help prevent against deteriorations in TOF resolution and TOF image quality in the wide range of PET count rates documented in clinical routine. Methods Variations, according to count rates, in timing resolution and in TOF-related enhancement of the quality of phantom images were compared between the first fully digital PET (Vereos) and a PMT-based PET (Ingenuity). Single-count rate values were additionally extracted from the list-mode data of routine analog- and digital-PET exams at each 500-ms interval, in order to determine the ranges of routine PET count rates. Results Routine PET count rates were lower for the Vereos than for the Ingenuity. For Ingenuity, the upper limits were estimated at approximately 21.7 and 33.2 Mcps after injection of respectively 3 and 5 MBq.kg-1 of current 18F-labeled tracers. At 5.8 Mcps, corresponding to the lower limit of the routine count rates documented with the Ingenuity, timing resolutions provided by the scatter phantom were 326 and 621 ps for Vereos and Ingenuity, respectively. At higher count rates, timing resolution was remarkably stable for Vereos but exhibited a progressive deterioration for Ingenuity, respectively reaching 732 and 847 ps at the upper limits of 21.7 and 33.2 Mcps. The averaged TOF-related gain in signal/noise ratio was stable at approximately 2 for Vereos but decreased from 1.36 at 5.8 Mcps to 1.14 and 1.00 at respectively 21.7 and 33.2 Mcps for Ingenuity. Conclusion Contrary to the Ingenuity PMT-based PET, the Vereos fully digital PET is unaffected by any deterioration in TOF resolution and consequently, in the quality of TOF images, in the wide range of routine PET count rates. This advantage is even more striking with higher count-rates for which the preferential use of digital PET should be further recommended (i.e., dynamic PET recording, higher injected activities).

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Patterns of use, effectiveness and safety of gadolinium contrast agents: a European prospective cross-sectional multicentre observational study

BMC Medical Imaging ◽

10.1186/s12880-021-00600-9 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Jarl Åsbjørn Jakobsen ◽

Carlo Cosimo Quattrocchi ◽

Frank H. H. Müller ◽

Olivier Outteryck ◽

Andrés Alcázar ◽

...

Keyword(s):

Image Quality ◽

Observational Study ◽

Contrast Agents ◽

Marketing Authorisation ◽

Safety Data ◽

Radiological Diagnosis ◽

Routine Practice ◽

Diagnostic Confidence ◽

Cross Sectional ◽

Wide Range

Abstract Background The EU gadolinium-based contrast agents (GBCA) market has changed in recent years due to the European Medicines Agency decision to suspend the marketing authorisation of linear GBCA and the marketing authorisation of new generic macrocyclic GBCA. The study aims to understand the patterns of (GBCA) use, and to study the effectiveness and safety of GBCA in routine practice across Europe. Methods Prospective, cross-sectional, multicentre, observational study in patients undergoing contrast-enhanced magnetic resonance. Reported usage patterns included indication, referral and examination details. Assessment of effectiveness included changes in radiological diagnosis, diagnostic confidence and image quality. Safety data were collected by spontaneous patient adverse event (AE) reporting. Results 2118 patients were included from 8 centres across 5 European countries between December 2018 and November 2019. Clariscan, Dotarem (gadoteric acid), Gadovist (gadobutrol) and ProHance (gadoteridol) were utilised in 1513 (71.4%), 356 (16.8%), 237 (11.2%) and 12 (0.6%) patients, respectively. Most were performed in CNS-related indications (46.2%). Mean GBCA doses were 0.10 mmol/kg body weight, except for Gadovist (mean 0.12 mmol/kg). GBCA use increased confidence in diagnosis in 96.2% of examinations and resulted in a change in radiological diagnosis in 73.9% of patients. Image quality was considered excellent or good in 96.1% of patients and across all GBCA. Four patients reported AEs (0.19%), with only 1 (0.05%) considered serious. Conclusions This European study confirmed that GBCAs are used appropriately in Europe for a wide range of indications. The study demonstrated a significant increase in diagnostic confidence after GBCA use and confirmed the good safety profile of GBCAs, with comparable results for all agents used.

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Long-term improvements following a residential combined physical and psychological programme for chronic low back pain

BMJ Open Quality ◽

10.1136/bmjoq-2020-001068 ◽

2021 ◽

Vol 10 (2) ◽

pp. e001068

Author(s):

Shaun Wellburn ◽

Cormac G Ryan ◽

Andrew Coxon ◽

Alastair J Dickson ◽

D John Dickson ◽

...

Keyword(s):

Low Back Pain ◽

Back Pain ◽

Outcome Measures ◽

Chronic Low Back Pain ◽

Rating Scale ◽

Secondary Outcome ◽

Low Back ◽

Residential Setting ◽

Wide Range

ObjectivesEvaluate the outcomes and explore experiences of patients undergoing a residential combined physical and psychological programme (CPPP) for chronic low back pain.DesignA longitudinal observational cohort design, with a parallel qualitative design using semistructured interviews.SettingResidential, multimodal rehabilitation.Participants136 adults (62 male/74 female) referred to the CPPP, 100 (44 male/56 female) of whom completed the programme, during the term of the study. Ten (2 male/8 female) participated in the qualitative evaluation.InterventionA 3-week residential CPPP.Outcome measuresPrimary outcome measures were the STarT Back screening tool score; pain intensity—11-point Numerical Rating Scale; function—Oswestry Disability Index (ODI); health status/quality of life—EQ-5D-5L EuroQol five-Dimension-five level; anxiety—Generalised Anxiety Disorder-7; depression—Patient Health Questionnaire-9. Secondary outcome measures were the Global Subjective Outcome Scale; National Health Service Friends and Family Test;.ResultsAt discharge, 6 and 12 months follow ups, there were improvements from baseline that were greater than minimum clinically important differences in each of the outcomes (with the sole exception of ODI at discharge). At 12 months, the majority of people considered themselves a lot better (57%) and were extremely likely (86%) to recommend the programme to a friend. The qualitative data showed praise for the residential nature of the intervention and the opportunities for interaction with peers and peer support. There were testimonies of improvements in understanding of pain and how to manage it better. Some participants said they had reduced, or stopped, medication they had been taking to manage their pain.ConclusionsParticipants improved, and maintained long term, beyond minimum clinically important differences on a wide range of outcomes. Participants reported an enhanced ability to self-manage their back pain and support for the residential setting.

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Impact on dose and image quality of a software-based scatter correction in mammography

Acta Radiologica ◽

10.1177/0284185117730100 ◽

2017 ◽

Vol 59 (6) ◽

pp. 649-656 ◽

Cited By ~ 1

Author(s):

Teresa Monserrat ◽

Elena Prieto ◽

Benigno Barbés ◽

Luis Pina ◽

Arlette Elizalde ◽

...

Keyword(s):

Image Quality ◽

Scatter Correction ◽

Inverse Image ◽

Clinical Image ◽

Air Kerma ◽

Average Glandular Dose ◽

Standard Mode ◽

Entrance Surface Air Kerma ◽

Clinical Cases

Background In 2014, Siemens developed a new software-based scatter correction (Progressive Reconstruction Intelligently Minimizing Exposure [PRIME]), enabling grid-less digital mammography. Purpose To compare doses and image quality between PRIME (grid-less) and standard (with anti-scatter grid) modes. Material and Methods Contrast-to-noise ratio (CNR) was measured for various polymethylmethacrylate (PMMA) thicknesses and dose values provided by the mammograph were recorded. CDMAM phantom images were acquired for various PMMA thicknesses and inverse Image Quality Figure (IQFinv) was calculated. Values of incident entrance surface air kerma (ESAK) and average glandular dose (AGD) were obtained from the DICOM header for a total of 1088 pairs of clinical cases. Two experienced radiologists compared subjectively the image quality of a total of 149 pairs of clinical cases. Results CNR values were higher and doses were lower in PRIME mode for all thicknesses. IQFinv values in PRIME mode were lower for all thicknesses except for 40 mm of PMMA equivalent, in which IQFinv was slightly greater in PRIME mode. A mean reduction of 10% in ESAK and 12% in AGD in PRIME mode with respect to standard mode was obtained. The clinical image quality in PRIME and standard acquisitions resulted to be similar in most of the cases (84% for the first radiologist and 67% for the second one). Conclusion The use of PRIME software reduces, in average, the dose of radiation to the breast without affecting image quality. This reduction is greater for thinner and denser breasts.

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Psychometric Properties of the Pain Numeric Rating Scale When Applied to Multiple Body Regions among Professional Musicians

PLoS ONE ◽

10.1371/journal.pone.0161874 ◽

2016 ◽

Vol 11 (9) ◽

pp. e0161874 ◽

Cited By ~ 5

Author(s):

Mikhail Saltychev ◽

Heidi Vastamäki ◽

Ryan Mattie ◽

Zachary McCormick ◽

Martti Vastamäki ◽

...

Keyword(s):

Psychometric Properties ◽

Rating Scale ◽

Numeric Rating Scale ◽

Professional Musicians ◽

Body Regions ◽

Numeric Rating

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Efficacy of levomilnacipran extended-release in major depressive disorder: pooled analysis of 5 double-blind, placebo-controlled trials

CNS Spectrums ◽

10.1017/s1092852914000273 ◽

2014 ◽

Vol 20 (2) ◽

pp. 148-156 ◽

Cited By ~ 12

Author(s):

Stuart A. Montgomery ◽

Carl P. Gommoll ◽

Changzheng Chen ◽

William M. Greenberg

Keyword(s):

Major Depressive Disorder ◽

Depressive Disorder ◽

Extended Release ◽

Rating Scale ◽

Pooled Analysis ◽

Major Depressive ◽

Double Blind ◽

Madrs Score ◽

Wide Range ◽

Remission Rates

Introduction/ObjectivePost hoc analyses were conducted to evaluate the efficacy of levomilnacipran extended-release (ER) in subgroups of patients with major depressive disorder (MDD).MethodsData were pooled from 5 completed Phase II/III studies. Patients were categorized by sex, age, MDD duration, recurrence of MDD, current episode duration, number of prior episodes, and baseline Montgomery–Åsberg Depression Rating Scale (MADRS) score. Efficacy was evaluated by MADRS least squares (LS) mean change from baseline, response (MADRS improvement ≥50%), and remission (MADRS ≤10).ResultsIn the pooled population, treatment with levomilnacipran ER versus placebo resulted in greater improvement in MADRS score (−15.8 versus −12.9; LS mean difference, −2.9; P < .001) and higher response rates (44.7% versus 34.5%; P < .001). Comparable treatment effects were found in most subgroups. Remission rates in the overall population were higher for levomilnacipran ER versus placebo (27.7% versus 21.5%; P < .05); notably high remission rates were seen in patients with baseline MADRS score < 30 (48.8% versus 28.9%; P < .001).DiscussionClinically meaningful improvements in depressive symptoms were found across subgroups, including statistically significant outcomes for both response and remission.ConclusionLevomilnacipran ER was efficacious across a wide range of MDD patients, including men and women, ages 18–78, with varying histories and symptom severity.

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PENGARUH LAMAZE EXERCISE TERHADAP SKALA NYERI MENSTRUASI (DYSMENORRHOEA) PADA REMAJA PUTRI DI SMA BUDI MULIA JAKARTA

KOSALA : Jurnal Ilmu Kesehatan ◽

10.37831/jik.v5i1.118 ◽

2017 ◽

Vol 5 (1) ◽

Author(s):

Veronica Yeni Rahmawati

Keyword(s):

Rating Scale ◽

Numeric Rating Scale ◽

Rank Test ◽

Menstrual Pain ◽

Significance Level ◽

Signed Rank ◽

Wide Range ◽

Post Test ◽

Signed Rank Test ◽

Pharmacological Method

Menstrual pain present as cramps (ranging from mild to severe), which may disturb dailyactivities. Lamaze exercise is non pharmacological method which use breathingrelaxation. This research was to analyze Lamaze exercise to reduction of menstrual pain.This study used pra experimental pre post test design. The population was the studentswith menstrual pain at Budi Mulia Senior High School Jakarta. The sampling techniquewas purposive sampling. Thirty one students participated in this study. The independentvariable was Lamaze exercise and the dependent variable was menstrual pain.Instrument which used to measure pain was Visual Analog Numeric Rating Scale. Datawere analyzed with Wilcoxon Signed Rank Test with significance α ≤ 0.005. The resultshowed that Lamaze exercise decreasd menstrual pain. The result of statistical testshowed significance level p = 0.000 and the deviation between pre and post mean is2.32, which means that there was decreasing menstrual pain in student in pre test andpost test. It can be concluded that Lamaze exercise can influence menstrual pain indecrease respondent of the research. Lamaze exercise can provide a relaxing effect.Further experiment with different respondent characteristic to obtain more wide range ofresult.Keywords: menstrual pain, Lamaze, relaxing effect, non pharmacological method

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The responsiveness of gait and balance outcomes to disease progression in Friedreich ataxia

10.1101/2021.03.18.434657 ◽

2021 ◽

Author(s):

Sarah C Milne ◽

Seok Hun Kim ◽

Anna Murphy ◽

Jane Larkindale ◽

Jennifer Farmer ◽

...

Keyword(s):

Effect Size ◽

Rating Scale ◽

Friedreich Ataxia ◽

Correlation Coefficients ◽

Berg Balance Scale ◽

Therapeutic Effects ◽

Balance System ◽

Gait Parameters ◽

Wide Range ◽

Daily Step Count

Objective: To identify gait and balance measures that are responsive to change during the timeline of a clinical trial in Friedreich ataxia (FRDA) we administered a battery of potential measures three times over a 12-month period. Methods: Sixty-one ambulant individuals with FRDA underwent assessment of gait and balance at baseline, six months and 12 months. Outcomes included: GAITRite spatiotemporal gait parameters; Biodex Balance System Postural Stability Test (PST) and Limits of Stability; Berg Balance Scale (BBS); Timed 25 Foot Walk Test; Dynamic Gait Index (DGI); SenseWear MF Armband step and energy activity; and the Friedreich Ataxia Rating Scale Upright Stability Subscale (FARS USS). The standardised response mean (SRM) or correlation coefficients were reported as effect size indices for comparison of internal responsiveness. Internal responsiveness was also analysed in subgroups. Results: SenseWear Armband daily step count had the largest effect size of all the variables over six months (SRM=-0.615), while the PST medial-lateral index had the largest effect size (SRM=0.829) over 12 months. The FARS USS (SRM=0.824) and BBS (SRM=-0.720) were the only outcomes able to detect change over 12 months in all subgroups. The DGI was the most responsive outcome in children, detecting a mean change of -2.59 (95% CI -3.52 to -1.66, p<0.001, SRM=-1.429). Conclusions: The FARS USS and BBS are highly responsive and can detect change in a wide range of ambulant individuals with FRDA. However, therapeutic effects in children may be best measured by the DGI.

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