Deep Learning for Pneumothorax Detection on Chest Radiograph: A Diagnostic Test Accuracy Systematic Review and Meta Analysis

BACKGROUND

Pneumothorax is a common acute presentation in healthcare settings. A chest radiograph (CXR) is often necessary to make the diagnosis, and minimizing the time between presentation and diagnosis is critical to deliver optimal treatment. Deep learning (DL) algorithms have been developed to rapidly identify pathologic findings on various imaging modalities.

PURPOSE

The purpose of this systematic review and meta-analysis was to evaluate the overall performance of studies utilizing DL algorithms to detect pneumothorax on CXR.

METHODS

A study protocol was created and registered a priori (PROSPERO CRD42023391375). The search strategy included studies published up until January 10, 2023. Inclusion criteria were studies that used adult patients, utilized computer-aided detection of pneumothorax on CXR, dataset was evaluated by a qualified physician, and sufficient data was present to create a 2 × 2 contingency table. Risk of bias was assessed using the QUADAS-2 tool. Bivariate random effects meta-analyses and meta-regression modeling were performed.

RESULTS

Twenty-three studies were selected, including 34 011 patients and 34 075 CXRs. The pooled sensitivity and specificity were 87% (95% confidence interval, 81%, 92%) and 95% (95% confidence interval, 92%, 97%), respectively. The study design, use of an institutional/public data set and risk of bias had no significant effect on the sensitivity and specificity of pneumothorax detection.

CONCLUSIONS

The relatively high sensitivity and specificity of pneumothorax detection by deep-learning showcases the vast potential for implementation in clinical settings to both augment the workflow of radiologists and assist in more rapid diagnoses and subsequent patient treatment.

Percentage of Pancreatic Cysts on MRI With a Pancreatic Carcinoma: Systematic Review and Meta-Analysis

BACKGROUND

Pancreatic cystic lesions (PCLs) are frequent on MRI and are thought to be associated with pancreatic adenocarcinoma (PDAC) necessitating long-term surveillance based on older studies suffering from selection bias.

PURPOSE

To establish the percentage of patients with PCLs on MRI with a present or future PDAC.

STUDY TYPE

Systematic review, meta-analysis.

POPULATION

Adults with PCLs on MRI and a present or future diagnosis of PDAC were eligible. MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Scopus were searched to April 2022 (PROSPERO:CRD42022320502). Studies limited to PCLs not requiring surveillance, <100 patients, or those with a history/genetic risk of PDAC were excluded.

FIELD STRENGTH/SEQUENCE

≥1.5 T with ≥1 T2-weighted sequence.

ASSESSMENT

Two investigators extracted data, with discrepancies resolved by a third. QUADAS-2 assessed bias. PDAC was diagnosed using a composite reference standard.

STATISTICAL TESTS

A meta-analysis of proportions was performed at the patient-level with 95% confidence intervals (95% CI).

RESULTS

Eight studies with 1289 patients contributed to the percentage of patients with a present diagnosis of PDAC, and 10 studies with 3422 patients to the percentage with a future diagnosis. Of patients with PCLs on MRI, 14.8% (95% CI 2.4-34.9) had a PDAC at initial MRI, which decreased to 6.0% (2.2-11.3) for studies at low risk of bias. For patients without PDAC on initial MRI, 2.0% (1.1-3.2) developed PDAC during surveillance, similar for low risk of bias studies at 1.9% (0.7-3.6), with no clear trend of increased PDAC for longer surveillance durations. For patients without worrisome features or high-risk stigmata, 0.9% (0.1-2.2) developed PDAC during surveillance. Of 10, eight studies had a median surveillance ≥3 years (range 3-157 months). Sources of bias included retrospectively limiting PCLs to those with histopathology and inconsistent surveillance protocols.

DATA CONCLUSION

A low percentage of patients with PCLs on MRI develop PDAC while on surveillance. The first MRI revealing a PCL should be scrutinized for PDAC.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY: Stage 2.

MRI-guided Minimally Invasive Focal Therapies for Prostate Cancer

Two cases involving patients diagnosed with localized prostate cancer and treated with MRI-guided focal therapies are presented. Patient selection procedures, techniques, outcomes, challenges, and future directions of MRI-guided focal therapies, as well as their role in the treatment of low- to intermediate-risk localized prostate cancer, are summarized.

MRI vs. CT for pancreatic adenocarcinoma vascular invasion: comparative diagnostic test accuracy systematic review and meta-analysis

OBJECTIVES

To perform a systematic review comparing the diagnostic accuracy of MRI vs. CT for assessing pancreatic ductal adenocarcinoma (PDAC) vascular invasion.

METHODS

MEDLINE, EMBASE, Cochrane Central, and Scopus were searched until December 2021 for diagnostic accuracy studies comparing MRI vs. CT to evaluate vascular invasion of pathologically confirmed PDAC in the same patients. Findings on resection or exploratory laparotomy were the preferred reference standard. Data extraction, risk of bias, and applicability assessment were performed by two authors using the Quality Assessment of Diagnostic Accuracy Studies-Comparative Tool. Bivariate random-effects meta-analysis and meta-regression were performed with 95% confidence intervals (95% CI).

RESULTS

Three studies were included assessing 474 vessels without vascular invasion and 65 with vascular invasion in 107 patients. All patients were imaged using MRI at ≥ 1.5 T and a pancreatic protocol CT. No difference was shown between MRI and CT for diagnosing PDAC vascular invasion: MRI/CT sensitivity (95% CI) were 71% (47-87%)/74% (56-86%), and specificity were 97% (94-99%)/97% (94-98%). Sources of bias included selection bias from only a subset of CT patients undergoing MRI and verification bias from patients with unresectable disease not confirmed on surgery. No patients received neoadjuvant therapy prior to staging.

CONCLUSIONS

Based on limited data, no difference was observed between MRI and pancreatic protocol CT for PDAC vascular invasion assessment. MRI may be an adequate substitute for pancreatic protocol CT in some patients, particularly those who have already had a single-phase CT. Larger and more recent cohort studies at low risk of bias, including patients who have received neoadjuvant therapy, are needed.

CLINICAL RELEVANCE STATEMENT

Abdominal MRI performed similarly to pancreatic protocol CT at assessing pancreatic ductal adenocarcinoma vascular invasion, suggesting local staging is adequate in some patients using MRI. More data are needed using larger, more recent cohorts including patients with neoadjuvant treatment.

KEY POINTS

• Based on limited data, no difference was found between MRI and pancreatic protocol CT sensitivity and specificity for diagnosing PDAC vascular invasion (p = 0.81, 0.73 respectively). • Risk of bias could be reduced in future PDAC MRI vs CT comparative diagnostic test accuracy research by ensuring all enrolled patients undergo both imaging modalities being compared in random order and regardless of the findings on either modality. • More studies are needed that directly compare the diagnostic performance of MRI and CT for PDAC staging after neoadjuvant therapy.

Barriers to Screening At-risk Populations in Canada

Cancer screening is invaluable for early detection of disease, including for breast and lung cancer. Through early detection, cancer treatment can be commenced prior to the development of advanced stage disease, significantly reducing morbidity and mortality. However, eligible patients may face barriers when accessing screening services, and some groups may be more disproportionately affected than others. This review aims to describe some of the most prominent barriers that at-risk populations may face when accessing image-based cancer screening services in Canada. Characterizing these barriers would be helpful in determining the best strategies to increase uptake to these screening services and, consequently, improve health equity.

Quality improvement strategies for diabetes care: Effects on outcomes for adults living with diabetes

BACKGROUND

There is a large body of evidence evaluating quality improvement (QI) programmes to improve care for adults living with diabetes. These programmes are often comprised of multiple QI strategies, which may be implemented in various combinations. Decision-makers planning to implement or evaluate a new QI programme, or both, need reliable evidence on the relative effectiveness of different QI strategies (individually and in combination) for different patient populations.

OBJECTIVES

To update existing systematic reviews of diabetes QI programmes and apply novel meta-analytical techniques to estimate the effectiveness of QI strategies (individually and in combination) on diabetes quality of care.

SEARCH METHODS

We searched databases (CENTRAL, MEDLINE, Embase and CINAHL) and trials registers (ClinicalTrials.gov and WHO ICTRP) to 4 June 2019. We conducted a top-up search to 23 September 2021; we screened these search results and 42 studies meeting our eligibility criteria are available in the awaiting classification section.

SELECTION CRITERIA

We included randomised trials that assessed a QI programme to improve care in outpatient settings for people living with diabetes. QI programmes needed to evaluate at least one system- or provider-targeted QI strategy alone or in combination with a patient-targeted strategy. - System-targeted: case management (CM); team changes (TC); electronic patient registry (EPR); facilitated relay of clinical information (FR); continuous quality improvement (CQI). - Provider-targeted: audit and feedback (AF); clinician education (CE); clinician reminders (CR); financial incentives (FI). - Patient-targeted: patient education (PE); promotion of self-management (PSM); patient reminders (PR). Patient-targeted QI strategies needed to occur with a minimum of one provider or system-targeted strategy.

DATA COLLECTION AND ANALYSIS

We dual-screened search results and abstracted data on study design, study population and QI strategies. We assessed the impact of the programmes on 13 measures of diabetes care, including: glycaemic control (e.g. mean glycated haemoglobin (HbA1c)); cardiovascular risk factor management (e.g. mean systolic blood pressure (SBP), low-density lipoprotein cholesterol (LDL-C), proportion of people living with diabetes that quit smoking or receiving cardiovascular medications); and screening/prevention of microvascular complications (e.g. proportion of patients receiving retinopathy or foot screening); and harms (e.g. proportion of patients experiencing adverse hypoglycaemia or hyperglycaemia). We modelled the association of each QI strategy with outcomes using a series of hierarchical multivariable meta-regression models in a Bayesian framework. The previous version of this review identified that different strategies were more or less effective depending on baseline levels of outcomes. To explore this further, we extended the main additive model for continuous outcomes (HbA1c, SBP and LDL-C) to include an interaction term between each strategy and average baseline risk for each study (baseline thresholds were based on a data-driven approach; we used the median of all baseline values reported in the trials). Based on model diagnostics, the baseline interaction models for HbA1c, SBP and LDL-C performed better than the main model and are therefore presented as the primary analyses for these outcomes. Based on the model results, we qualitatively ordered each QI strategy within three tiers (Top, Middle, Bottom) based on its magnitude of effect relative to the other QI strategies, where 'Top' indicates that the QI strategy was likely one of the most effective strategies for that specific outcome. Secondary analyses explored the sensitivity of results to choices in model specification and priors.  Additional information about the methods and results of the review are available as Appendices in an online repository. This review will be maintained as a living systematic review; we will update our syntheses as more data become available.

MAIN RESULTS

We identified 553 trials (428 patient-randomised and 125 cluster-randomised trials), including a total of 412,161 participants. Of the included studies, 66% involved people living with type 2 diabetes only. Participants were 50% female and the median age of participants was 58.4 years. The mean duration of follow-up was 12.5 months. HbA1c was the commonest reported outcome; screening outcomes and outcomes related to cardiovascular medications, smoking and harms were reported infrequently. The most frequently evaluated QI strategies across all study arms were PE, PSM and CM, while the least frequently evaluated QI strategies included AF, FI and CQI. Our confidence in the evidence is limited due to a lack of information on how studies were conducted.  Four QI strategies (CM, TC, PE, PSM) were consistently identified as 'Top' across the majority of outcomes. All QI strategies were ranked as 'Top' for at least one key outcome. The majority of effects of individual QI strategies were modest, but when used in combination could result in meaningful population-level improvements across the majority of outcomes. The median number of QI strategies in multicomponent QI programmes was three.  Combinations of the three most effective QI strategies were estimated to lead to the below effects:  - PR + PSM + CE: decrease in HbA1c by 0.41% (credibility interval (CrI) -0.61 to -0.22) when baseline HbA1c < 8.3%; - CM + PE + EPR: decrease in HbA1c by 0.62% (CrI -0.84 to -0.39) when baseline HbA1c > 8.3%;  - PE + TC + PSM: reduction in SBP by 2.14 mmHg (CrI -3.80 to -0.52) when baseline SBP < 136 mmHg; - CM + TC + PSM: reduction in SBP by 4.39 mmHg (CrI -6.20 to -2.56) when baseline SBP > 136 mmHg;  - TC + PE + CM: LDL-C lowering of 5.73 mg/dL (CrI -7.93 to -3.61) when baseline LDL < 107 mg/dL; - TC + CM + CR: LDL-C lowering by 5.52 mg/dL (CrI -9.24 to -1.89) when baseline LDL > 107 mg/dL. Assuming a baseline screening rate of 50%, the three most effective QI strategies were estimated to lead to an absolute improvement of 33% in retinopathy screening (PE + PR + TC) and 38% absolute increase in foot screening (PE + TC + Other).

AUTHORS' CONCLUSIONS

There is a significant body of evidence about QI programmes to improve the management of diabetes. Multicomponent QI programmes for diabetes care (comprised of effective QI strategies) may achieve meaningful population-level improvements across the majority of outcomes. For health system decision-makers, the evidence summarised in this review can be used to identify strategies to include in QI programmes. For researchers, this synthesis identifies higher-priority QI strategies to examine in further research regarding how to optimise their evaluation and effects. We will maintain this as a living systematic review.

The growing role of social media for research and education in radiology

While the adoption of social media platforms has become commonplace for personal life use, its practice has tremendously grown for professional usage in medicine, and particularly in the field of radiology. The use of alternative metrics, or altmetrics, scores have developed in an effort to quantify the impact of research beyond traditional metrics, such as citation rate and journal impact factor, particularly to recognize the impact of social media on dissemination and promotion of research. Social media usage in the realm of radiology has expectedly been adopted for the purposes of medical education, research, networking, and advocacy. However, some platforms have been used as a medium to discuss and share the day-to-day nature in the field of radiology, burnout in radiology, as well as radiology-themed humor. The purpose of this review article was discuss the role of altmetrics, as well as the specific uses of social media platforms including Twitter, Instagram, Facebook, Youtube, and more. The role of ethics in social media practice related to radiology are discussed.

Magnetic resonance imaging-guided ultrasound ablation for prostate cancer - A contemporary review of performance

Prostate cancer (PCa) is one of the most common malignancies in men, but patient outcomes are varied depending on extent of disease. Radical, whole-gland therapies, such as prostatectomy or radiotherapy, are definitive treatments for PCa, but they are associated with significant morbidity, including erectile dysfunction and urinary incontinence. Focal therapies for PCa, whereby the part of gland harboring disease is selectively treated, spares the normal surrounding structures, and minimizes the morbidity associated with whole gland treatment. The use of magnetic resonance imaging (MRI) guidance provides advantages over ultrasound guidance, such as better localization and targeting of clinically significant PCa (csPCa), as well as MRI thermometry which optimizes tissue ablation temperatures. This review will discuss two MRI-guided high-intensity focused ultrasound (HIFU) techniques - transrectal MR-guided focused ultrasound (MRgFUS) and TULSA (transurethral ultrasound ablation) ablation for localized PCa. Overall, recent major trials for MRgFUS and TULSA have shown promising oncological and functional results in the treatment of low- to intermediate-risk PCa. Recent Phase II MRgFUS trials have shown better oncologic outcomes than the published results for focal ultrasound guided HIFU and may justify the additional costs associated with MRI guidance. While initial studies on TULSA have focused on subtotal gland ablation, recent trials assessing oncological outcomes for focal treatment of angular sectors have shown promise.

Association of Accuracy, Conclusions, and Reporting Completeness With Acceptance by Radiology Conferences and Journals

BACKGROUND

Preferential publication of studies with positive findings can lead to overestimation of diagnostic test accuracy (i.e. publication bias). Understanding the contribution of the editorial process to publication bias could inform interventions to optimize the evidence guiding clinical decisions.

PURPOSE/HYPOTHESIS

To evaluate whether accuracy estimates, abstract conclusion positivity, and completeness of abstract reporting are associated with acceptance to radiology conferences and journals.

STUDY TYPE

Meta-research.

POPULATION

Abstracts submitted to radiology conferences (European Society of Gastrointestinal and Abdominal Radiology (ESGAR) and International Society for Magnetic Resonance in Medicine (ISMRM)) from 2008 to 2018 and manuscripts submitted to radiology journals (Radiology, Journal of Magnetic Resonance Imaging [JMRI]) from 2017 to 2018. Primary clinical studies evaluating sensitivity and specificity of a diagnostic imaging test in humans with available editorial decisions were included.

ASSESSMENT

Primary variables (Youden's index [YI > 0.8 vs. <0.8], abstract conclusion positivity [positive vs. neutral/negative], number of reported items on the Standards for Reporting of Diagnostic Accuracy Studies [STARD] for Abstract guideline) and confounding variables (prospective vs. retrospective/unreported, sample size, study duration, interobserver agreement assessment, subspecialty, modality) were extracted.

STATISTICAL TESTS

Multivariable logistic regression to obtain adjusted odds ratio (OR) as a measure of the association between the primary variables and acceptance by radiology conferences and journals; 95% confidence intervals (CIs) and P-values were obtained; the threshold for statistical significance was P < 0.05.

RESULTS

A total of 1000 conference abstracts (500 ESGAR and 500 ISMRM) and 1000 journal manuscripts (505 Radiology and 495 JMRI) were included. Conference abstract acceptance was not significantly associated with YI (adjusted OR = 0.97 for YI > 0.8; CI = 0.70-1.35), conclusion positivity (OR = 1.21 for positive conclusions; CI = 0.75-1.90) or STARD for Abstracts adherence (OR = 0.96 per unit increase in reported items; CI = 0.82-1.18). Manuscripts with positive abstract conclusions were less likely to be accepted by radiology journals (OR = 0.45; CI = 0.24-0.86), while YI (OR = 0.85; CI = 0.56-1.29) and STARD for Abstracts adherence (OR = 1.06; CI = 0.87-1.30) showed no significant association. Positive conclusions were present in 86.7% of submitted conference abstracts and 90.2% of journal manuscripts.

DATA CONCLUSION

Diagnostic test accuracy studies with positive findings were not preferentially accepted by the evaluated radiology conferences or journals.

EVIDENCE LEVEL

3 TECHNICAL EFFICACY: Stage 2.

Value of second opinion subspecialty radiology consultation in suspected abdominal medium vessel vasculitis

PURPOSE

To perform a descriptive analysis of individuals with suspected Polyarteritis nodosa (PAN) referred for second opinion imaging consultation.

METHODS

A retrospective observational cohort study was performed at a single institution. A consecutive sample was performed of individuals who underwent a second opinion CT or MR angiography subspecialty radiologist consultation between January 2008 and September 2019 for suspected abdominal medium vessel vasculitis. Demographic, clinical, and imaging data were collected. Clinical and imaging findings were reported for PAN, small vessel vasculitis, and "non-vasculitis" groups. Agreement and diagnostic accuracy between final clinical and second opinion imaging diagnoses for PAN were determined. Two-tailed t-tests with a significant p-value < 0.05 were utilized.

RESULTS

Of the 58 participants, 9 were clinically diagnosed with PAN, 11 with small vessel vasculitis (including lupus, IgA, and ANCA-associated vasculitis), and 38 with non-vasculitis diagnoses. The non-vasculitis group included 15 SAM, 3 FMD, and 1 SAM-FMD spectrum diagnoses. Higher C-reactive protein level (51 vs 17, p = 0.04) and superior mesenteric artery involvement (56% vs 21%, p = 0.04) were more common in PAN than non-vasculitis diagnoses, while arterial dissection (40% vs 0%, p = 0.02) and celiac vasculature involvement (53% vs 0%, p = 0.003) were more common in the non-vasculitis group. There was 88% agreement (51/58; Cohen's kappa 0.56); sensitivity was 67% [95%-confidence interval (CI) 30-93%] and specificity was 92% (95%-CI 80-98%).

CONCLUSION

Isolated celiac artery involvement and arterial dissection were more common in non-inflammatory vasculopathies than PAN. Our findings highlight the need for multidisciplinary collaboration and awareness of the diverse findings of abdominal vasculopathies.

Diagnostic Test Accuracy of Ultrasonography vs Computed Tomography for Papillary Thyroid Cancer Cervical Lymph Node Metastasis: A Systematic Review and Meta-analysis

Importance

The use of ultrasonography (US) vs cross-sectional imaging for preoperative evaluation of papillary thyroid cancer is debated.

Objective

To compare thyroid US and computed tomography (CT) in the preoperative evaluation of papillary thyroid cancer for cervical lymph node metastasis (CLNM), as well as extrathyroidal disease extension.

Data Sources

MEDLINE and Embase were searched from January 1, 2000, to July 18, 2020.

Study Selection

Studies reporting on the diagnostic accuracy of US and/or CT in individuals with treatment-naive papillary thyroid cancer for CLNM and/or extrathyroidal disease extension were included. The reference standard was defined as histopathology/cytology or imaging follow-up. Independent title and abstract review (2515 studies) followed by full-text review (145 studies) was completed by multiple investigators.

Data Extraction and Synthesis

PRISMA guidelines were followed. Methodologic and diagnostic accuracy data were abstracted independently by multiple investigators. Risk of bias assessment was conducted using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool independently and in duplicate. Bivariate random-effects model meta-analysis and multivariable meta-regression modeling was used.

Main Outcomes and Measures

Diagnostic test accuracy of US and CT of the neck for lateral and central compartment CLNM, as well as for extrathyroidal disease extension, determined prior to study commencement.

Results

A total of 47 studies encompassing 31 942 observations for thyroid cancer (12 771 with CLNM; 1747 with extrathyroidal thyroid extension) were included; 21 and 26 studies were at low and high risk for bias, respectively. Based on comparative design studies, US and CT demonstrated no significant difference in sensitivity (73% [95% CI, 64%-80%] and 77% [95% CI, 67%-85%], respectively; P = .11) or specificity (89% [95% CI, 80%-94%] and 88% [95% CI, 79%-94%], respectively; P = .79) for lateral compartment CLNM. For central compartment metastasis, sensitivity was higher in CT (39% [95% CI, 27%-52%]) vs US (28% [95% CI, 21%-36%]; P = .004), while specificity was higher in US (95% [95% CI, 92%-98%]) vs CT (87% [95% CI, 77%-93%]; P < .001). Ultrasonography demonstrated a sensitivity of 91% (95% CI, 81%-96%) and specificity of 47% (95% CI, 35%-60%) for extrathyroidal extension.

Conclusions and Relevance

The findings of this systematic review and meta-analysis suggest that further study is warranted of the role of CT for papillary thyroid cancer staging, possibly as an adjunct to US.

General Review on the Current Management of Incidental Findings on Cross-Sectional Imaging: What Guidelines to Use, How to Follow Them, and Management and Medical-Legal Considerations

"Incidentalomas" are a common part of daily practice for radiologists, and knowledge of appropriate management guidelines is important in ensuring that no potentially clinically relevant findings are missed or are lost to follow-up in asymptomatic patients. Incidental findings of the brain, spine, thyroid, lungs, breasts, liver, adrenals, spleen, pancreas, kidneys, bowel, and ovaries are discussed, including where to find guidelines for management recommendations, how to follow them, and medical-legal considerations.

Use of Intravenous Gadolinium-based Contrast Media in Patients with Kidney Disease and the Risk of Nephrogenic Systemic Fibrosis: Radiology In Training

A 66-year-old male patient with end-stage chronic kidney disease undergoing maintenance dialysis and with a history of group I intravenous gadolinium-based contrast media (GBCM) administration presented with clinical and pathologic findings consistent with nephrogenic systemic fibrosis. A summary of the evidence and recommendations for use of intravenous GBCM in patients with kidney disease is presented. © RSNA, 2021.

Performance of Digital Breast Tomosynthesis, Synthetic Mammography, and Digital Mammography in Breast Cancer Screening: A Systematic Review and Meta-Analysis

BACKGROUND

Our objective was to perform a systematic review and meta-analysis comparing the breast cancer detection rate (CDR), invasive CDR, recall rate, and positive predictive value 1 (PPV1) of digital mammography (DM) alone, combined digital breast tomosynthesis (DBT) and DM, combined DBT and synthetic 2-dimensional mammography (S2D), and DBT alone.

METHODS

MEDLINE and Embase were searched until April 2020 to identify comparative design studies reporting on patients undergoing routine breast cancer screening. Random effects model proportional meta-analyses estimated CDR, invasive CDR, recall rate, and PPV1. Meta-regression modeling was used to compare imaging modalities. All statistical tests were 2-sided.

RESULTS

Forty-two studies reporting on 2 606 296 patients (13 003 breast cancer cases) were included. CDR was highest in combined DBT and DM (6.36 per 1000 screened, 95% confidence interval [CI] = 5.62 to 7.14, P < .001), and combined DBT and S2D (7.40 per 1000 screened, 95% CI = 6.49 to 8.37, P < .001) compared with DM alone (4.68 per 1000 screened, 95% CI = 4.28 to 5.11). Invasive CDR was highest in combined DBT and DM (4.53 per 1000 screened, 95% CI = 3.97 to 5.12, P = .003) and combined DBT and S2D (5.68 per 1000 screened, 95% CI = 4.43 to 7.09, P < .001) compared with DM alone (3.42 per 1000 screened, 95% CI = 3.02 to 3.83). Recall rate was lowest in combined DBT and S2D (42.3 per 1000 screened, 95% CI = 37.4 to 60.4, P<.001). PPV1 was highest in combined DBT and DM (10.0%, 95% CI = 8.0% to 12.0%, P = .004), and combined DBT and S2D (16.0%, 95% CI = 10.0% to 23.0%, P < .001), whereas no difference was detected for DBT alone (7.0%, 95% CI = 6.0% to 8.0%, P = .75) compared with DM alone (7.0%, 95.0% CI = 5.0% to 8.0%).

CONCLUSIONS

Our findings provide evidence on key performance metrics for DM, DBT alone, combined DBT and DM, and combined DBT and S2D, which may inform optimal application of these modalities for breast cancer screening.

Diagnostic Accuracy of MRI for Differentiation of Benign and Malignant Pancreatic Cystic Lesions Compared to CT and Endoscopic Ultrasound: Systematic Review and Meta-analysis

BACKGROUND

Differentiation of benign and malignant pancreatic cystic lesions on MRI, computed tomography (CT), and endoscopic ultrasound (EUS) is critical for determining management.

PURPOSE

To perform a systematic review evaluating the diagnostic accuracy of MRI for diagnosing malignant pancreatic cystic lesions, and to compare the accuracy of MRI to CT and EUS.

STUDY TYPE

Systematic review and meta-analysis.

DATA SOURCES

MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Web of Science, and Scopus were searched until February 2020 for studies reporting MRI accuracy for assessing pancreatic cystic lesions.

FIELD STRENGTH

1.5T or 3.0T.

ASSESSMENT

Methodologic and outcome data were extracted by two reviewers (AU and MA, 2 years of experience each). All studies of pancreatic cystic lesions on MRI were identified. Studies with incomplete MRI technique were excluded. Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool.

STATISTICAL TESTS

Sensitivity/specificity was pooled using bivariate random-effects meta-analysis with 95% confidence intervals (95%CI). Pairwise-comparison of MRI to CT and EUS was performed. The impact of gadolinium-based contrast agents, mucinous lesions, and risk of bias were explored using meta-regression.

RESULTS

MRI pooled sensitivity was 76% (95%CI 67% to 84%) and specificity was 80% (95%CI 74% to 85%) for distinguishing benign and malignant lesions. MRI and CT had similar sensitivity (P = 0.822) and specificity (P = 0.096), but MRI was more specific than EUS (80% vs. 75%, P < 0.05). Studies including only contrast-enhanced MRI were more sensitive than those including unenhanced exams (P < 0.05). MRI sensitivity and specificity did not differ for mucinous lesions (P = 0.537 and P = 0.384, respectively) or for studies at risk of bias (P = 0.789 and P = 0.791, respectively).

DATA CONCLUSION

MRI and CT demonstrate comparable accuracy for diagnosing malignant pancreatic cystic lesions. EUS is less specific than MRI, which suggests that, in some cases, management should be guided by MRI findings rather than EUS.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY STAGE: 2.

MRI vs. CT for the Detection of Liver Metastases in Patients With Pancreatic Carcinoma: A Comparative Diagnostic Test Accuracy Systematic Review and Meta-Analysis

BACKGROUND

The detection of liver metastases is important for pancreatic cancer curative treatment eligibility. The data suggest that magnetic resonance imaging (MRI) is more sensitive than computed tomography (CT) for the diagnosis of pancreatic cancer liver metastases. However, MRI is not currently recommended in multiple published guidelines.

PURPOSE

To perform a comparative diagnostic test accuracy systematic review and meta-analysis comparing CT and MRI for pancreatic cancer liver metastases detection.

STUDY TYPE

Systematic review and meta-analysis.

DATA SOURCES

MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Scopus, and multiple radiology society meeting archives were searched until November 2018. Comparative design studies reporting on liver CT and MRI accuracy for detection of pancreatic cancer liver metastases in the same cohort were included.

FIELD STRENGTH

1.5T or 3.0T.

ASSESSMENT

Demographic, methodologic, and diagnostic test accuracy data were extracted. Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool.

STATISTICAL TESTS

Accuracy metrics were obtained using bivariate random-effects meta-analysis. The impact of different covariates on accuracy estimates was assessed using a meta-regression model. Covariates included modality, study design, tumor characteristics, risk of bias, and imaging protocols.

RESULTS

Fourteen studies including 987 patients with pancreatic cancer (205 with liver metastases) were included. Sensitivity for CT and MRI was 45% (confidence intervals [95% CI] 21-71%) and 83% (95% CI 74-88%), respectively. Specificity for CT and MRI was 94% (95% CI 84-98%) and 96% (95% CI 93-97%), respectively. The greater observed sensitivity of MRI was preserved in the meta-regression model (P = 0.01), while no difference in specificity was detected (P = 0.16). CT sensitivity was highest for triphasic and quadriphasic examinations compared to single phase or biphasic protocols (P = 0.03). Most studies were at high risk of bias.

DATA CONCLUSION

MRI is more sensitive than CT for pancreatic cancer liver metastases detection, accounting for confounding variables. Consideration of this finding in clinical practice guidelines is recommended.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY STAGE: 3.

Impact of PI-RADS Category 3 lesions on the diagnostic accuracy of MRI for detecting prostate cancer and the prevalence of prostate cancer within each PI-RADS category: A systematic review and meta-analysis

OBJECTIVE

To evaluate Prostate Imaging Reporting and Data System (PI-RADS) category 3 lesions' impact on the diagnostic test accuracy (DTA) of MRI for prostate cancer (PC) and to derive the prevalence of PC within each PI-RADS category.

METHODS

MEDLINE and Embase were searched until April 10, 2020 for studies reporting on the DTA of MRI by PI-RADS category. Accuracy metrics were calculated using a bivariate random-effects meta-analysis with PI-RADS three lesions treated as a positive test, negative test, and excluded from the analysis. Differences in DTA were assessed utilizing meta-regression. PC prevalence within each PI-RADS category was estimated with a proportional meta-analysis.

RESULTS

In total, 26 studies reporting on 12,913 patients (4,853 with PC) were included. Sensitivities for PC in the positive, negative, and excluded test groups were 96% (95% confidence interval [CI] 92-98), 82% (CI 75-87), and 95% (CI 91-97), respectively. Specificities for the positive, negative, and excluded test groups were 33% (CI 23-44), 71% (CI 62-79), and 52% (CI 37-66), respectively. Meta-regression demonstrated higher sensitivity (p < 0.001) and lower specificity (p < 0.001) in the positive test group compared to the negative group. Clinically significant PC prevalences were 5.9% (CI 0-17.1), 11.4% (CI 6.5-17.3), 24.9% (CI 18.4-32.0), 55.7% (CI 47.8-63.5), and 81.4% (CI 75.9-86.4) for PI-RADS categories 1, 2, 3, 4 and 5, respectively.

CONCLUSION

PI-RADS category 3 lesions can significantly impact the DTA of MRI for PC detection. A low prevalence of clinically significant PC is noted in PI-RADS category 1 and 2 cases.

ADVANCES IN KNOWLEDGE

Inclusion or exclusion of PI-RADS category 3 lesions impacts the DTA of MRI for PC detection.

Female Authorship in Radiology: Trends in the Past Decade in CARJ

Purpose:

To identify trends in female authorship in the Canadian Association of Radiologists Journal (CARJ) from 2010 to 2019.

Methods:

We retrieved papers published in the CARJ over a 10-year period, and retrospectively reviewed 602 articles. All articles except editorials and advertisements were included. We categorized the names of the first and last position authors as female or male and excluded articles that had at least one author of which gender was not known. We compared the trends in the first and last position authors of the articles from 2010 to 2019. For statistical analysis, logistic regression was performed with reported odds ratios (ORs), and a P value of <.05 was defined as statistically significant.

Results:

Five hundred thirteen articles met inclusion criteria. Among them, 23 articles with a single author were classified as having only a first author. 39.8% (204/513) of first authors were female and 26.9% (132/490) of last authors were female. There has been an overall temporal increase in the odds of both the first and last author being female in CARJ publications (OR: 1.11, P = .034). Similarly, the odds a CARJ publication’s first author being female increased over time (OR: 1.07, P = .033). Female last author did not predict female first author (OR: 1.48, P = .056). There was no association identified between female last author and year of publication (OR: 1.04, P = .225).

Conclusion:

There has been an overall increase in engagement of female authorship in CARJ.

Factors Affecting Response Rates in Medical Imaging Survey Studies

RATIONALE AND OBJECTIVE

To review response rates published in medical imaging journals, and to analyze potential factors which contributed to a low response rate.

MATERIALS AND METHODS

A literature search was performed in MEDLINE and Embase to identify and assess published medical imaging survey studies. Variables assessed were response rate, incentives such as reminders and remuneration, and rationales provided for a potential low response rate. Statistical significance was calculated using unpaired t tests, ANOVA, Mann-Whitney, and Kruskal-Wallis tests.

RESULTS

Three hundred and fifty-six unique surveys were included for analysis. The mean survey response rate in the current age of predominately electronic surveys was 45%. Factors which statistically significantly demonstrated a difference in response rate were survey location (European countries: 52%, Canada: 47%, United States: 42%; p < 0.05), survey topic (musculoskeletal: 69%, nuclear medicine: 64%, and education: 47%; p < 0.05), survey delivery method (telephone: 76%, email: 41%; p < 0.0001), and survey question type (short answer: 62%, multiple choice: 43%; p < 0.01). Statistically significant linear correlations were observed between the response rate compared to the number of reminders sent (r = 0.27; p < 0.01) and the number of participants (r = -0.26; p < 0.0001).

CONCLUSION

The survey response rate serves as a surrogate marker for nonresponse bias. Survey response controlled for intrinsic nonadjustable characteristics offer achievable research goals. Adjustable factors to low response, including survey delivery method, question type, and number of reminders demonstrated statistical difference in response rate, and can be utilized by researchers to prospectively minimize nonresponse bias.

Imaging of blunt bowel and mesenteric injuries: Current status

Blunt abdominal trauma often presents a diagnostic challenge. Clinical examination demonstrates low reliability in detecting abdominal injury (16 %) when there is a history of head injury or loss of consciousness. This can prove detrimental, as delays in the diagnosis of traumatic bowel injury of 8 h or less can result in increased morbidity and mortality, as well as prolonged hospitalization. Although hemodynamically unstable patients will require an urgent laparotomy following clinical assessment, MDCT is the modality of choice for comprehensive imaging of blunt abdominal trauma in hemodynamically stable patients. Despite the use of MDCT, blunt injury to the bowel and mesentery, which accounts for up to 5% of injuries in cases of trauma, may be difficult to detect. The use of a constellation of direct and indirect signs on MDCT can help make the diagnosis and guide clinical management. Direct signs on MDCT, such as bowel wall discontinuity, and extraluminal gas may assist in the diagnosis of traumatic bowel injury. However, these signs are not sensitive. Therefore, the astute radiologist may have to rely on indirect signs of injury, such as free fluid, bowel wall thickening, and abnormal bowel wall enhancement to make the diagnosis. This review will focus on MDCT imaging findings of bowel and mesenteric injuries secondary to blunt abdominal trauma.

Beyond Universal Health Care: Barriers to Breast Cancer Screening Participation in Canada

PURPOSE

Despite well-established preventive screening guidelines for breast cancer, screening rates do not meet targets in both the United States and Canada. Although access to preventive care is an important factor toward participation, breast cancer screening rates in Canada vary despite a universal health care system. The objective of this study is to understand features within the Canadian population that potentiate screening disparities through a systematic review of the literature.

METHODS

A search of MEDLINE and Embase was performed to identify relevant studies published from 2005 onward. Titles and abstracts were screened, followed by full-text screening. Inclusion criteria were defined as studies reporting on disparities in image-based screening for breast cancer.

RESULTS

Three hundred twenty-four studies were retrieved, from which 29 studies were selected on the basis of the predetermined inclusion criteria. Population groups identified at risk for low image-based screening participation included those of low socioeconomic status, individuals with comorbidities, new immigrants and refugees, those in remote geographic locations, individuals with intellectual or developmental disabilities, and ethnocultural minorities. Barriers to image-based screening can be improved by targeting measures specific to these at-risk groups at the individual, organization, and policy levels.

CONCLUSIONS

Multiple at-risk population groups exist for preventive cancer screening within a universal health care system. By understanding specific characteristics within these vulnerable populations, effective intervention strategies can be established to improve breast cancer preventive care.

Predictors of Citation Rate for Original Research Studies in the Canadian Association of Radiologists Journal

OBJECTIVE

This study is aimed to identify predictors of citation rate of original research published in the Canadian Association of Radiologists Journal (CARJ).

METHODS

A search of MEDLINE was conducted from January 1, 2000-June 30, 2013 to identify all studies published in the CARJ. Original research studies were included. Reviews, pictorial essays, guidelines, case studies, case series, and original studies with a sample size <10 were excluded. Variables assessed for association with citation rate included number of authors, study design, sample size, multi-institutional study, multi-national study, study type, presence of statistically significant result, presence of funding, and number of references. Statistical analysis was completed using linear regression and Pearson correlation coefficients (r).

RESULTS

A total of 714 studies were published in CARJ, of which 181 were original research publications that were cited a total of 1517 times. Twelve original research studies were uncited, while the most-cited one was cited 58 times. Sample size (r = 0.177, P = .017) and number of references (r = 0.164, P = .028) demonstrated statistically significant weak positive correlations with citation rate. Number of authors, study design, setting, statistically significant results, and funding were not associated with citation rate.

CONCLUSION

Only a very small number of original research studies published at the CARJ remained uncited 5 or more years after the publication. Sample size and number of references were identified as significant, but weak predictors of citation rate in CARJ.

Breast Cancer Screening in High-Risk Patients during Pregnancy and Breastfeeding: A Systematic Review of the Literature

There are currently no clear guidelines for high-risk breast cancer screening during the pregnancy and breastfeeding periods. The objective of this systematic review (SR) was to assess the available evidence pertaining to breast cancer screening recommendations in this population with the aim of supporting future guidelines. We performed a SR of the literature using the electronic databases MEDLINE and Embase. Predetermined inclusion and exclusion criteria were used during the abstract screening and full-text data extraction phases. We retrieved 2,274 abstracts after removal of duplicates, from which 16 studies were included based on predetermined eligibility criteria. Most of the studies found were narrative reviews and expert opinions. Clinical breast exam (CBE) was recommended by 12 studies during pregnancy and by 6 studies in the breastfeeding period. Mammography was recommended in the breastfeeding period by 2 studies. Magnetic resonance imaging was recommended in the breastfeeding period by 2 studies. Ultrasound was considered not appropriate for screening in this population. The information extracted from this SR is based primarily on expert opinion and anecdotal evidence, which explains the lack of standardized guidelines for high-risk breast cancer screening in this population. However, expert opinion may be a surrogate outcome for high-risk breast cancer screening recommendations in this subset of patients, and as such, may justify the clinical management to be tailored accordingly. This SR summarizes the evidence pertaining to high-risk breast cancer screening during pregnancy and breastfeeding, which could serve as a catalyst for future research on the topic.

Recommendations for reporting of systematic reviews and meta-analyses of diagnostic test accuracy: a systematic review

BACKGROUND

This study is to perform a systematic review of existing guidance on quality of reporting and methodology for systematic reviews of diagnostic test accuracy (DTA) in order to compile a list of potential items that might be included in a reporting guideline for such reviews: Preferred Reporting Items for Systematic Reviews and Meta-Analyses of Diagnostic Test Accuracy (PRISMA-DTA).

METHODS

Study protocol published on EQUATOR website. Articles in full text or abstract form that reported on any aspect of reporting systematic reviews of diagnostic test accuracy were eligible for inclusion. We used the Ovid platform to search Ovid MEDLINE®, Ovid MEDLINE® In-Process & Other Non-Indexed Citations and Embase Classic+Embase through May 5, 2016. The Cochrane Methodology Register in the Cochrane Library (Wiley version) was also searched. Title and abstract screening followed by full-text screening of all search results was performed independently by two investigators. Guideline organization websites, published guidance statements, and the Cochrane Handbook for Diagnostic Test Accuracy were also searched. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Standards for Reporting Diagnostic Accuracy (STARD) were assessed independently by two investigators for relevant items.

RESULTS

The literature searched yielded 6967 results; 386 were included after title and abstract screening and 203 after full-text screening. After reviewing the existing literature and guidance documents, a preliminary list of 64 items was compiled into the following categories: title (three items); introduction (two items); methods (35 items); results (13 items); discussion (nine items), and disclosure (two items).

CONCLUSION

Items on the methods and reporting of DTA systematic reviews in the present systematic review will provide a basis for generating a PRISMA extension for DTA systematic reviews.

Efficacy of inhaled corticosteroids for patients with asthma: a descriptive review of randomized controlled trials

Objective: To evaluate the efficacy of inhaled corticosteroids (ICS) in patients with asthma based on changes in sputum eosinophil counts, through a review of relevant randomized controlled trials (RCTs).Methods: Studies were retrieved from MEDLINE, EMBASE, the SYSTEM FOR INFORMATION ON GREY LITERATURE, and the INSTITUTE FOR SCIENTIFIC INFORMATION from February 1, 2003 to February 1, 2013 based on a comprehensive search strategy. Articles were screened through two stages: title and abstract; and full-text screening. RCTs enrolling patients with asthma, testing an ICS intervention, and reporting outcomes on changes in sputum eosinophil counts pre- and post-intervention were included. Following screening, data extraction, and quality appraisal, a descriptive synthesis of trials was conducted.Results: The search strategy retrieved 447 articles, of which 66 articles underwent full-text screening, resulting in 37 RCTs that met the inclusion criteria for this review. The articles were stratified according to the type of ICS: budesonide, fluticasone propionate, ciclesonide, beclomethasone dipropionate, and mometasone.  Across trials, 9 of 16 budesonide, 5 of 14 fluticasone propionate, 4 of 9 of nine ciclesonide, 2 of 4 beclomethasone dipropionate, and 1 of 2 mometasone interventions demonstrated a statistically significant (p < 0.05) reduction in sputum eosinophil counts.Conclusion: This study detected differences between ICS treatments however the clinical relevance is uncertain. There is insufficient evidence to suggest the superiority of one ICS treatment over another. Further research needs to be conducted to evaluate the relative impact of ICS products upon eosinophil counts, as well as in clarifying what quantitative level of change in baseline eosinophil counts is required to observe a change in symptom improvement and disease control.

Consideration of chronic pain in trials to promote physical activity for diabetes: a systematic review of randomized controlled trials

Background

Chronic pain has been estimated to affect 60% of patients with diabetes and is strongly associated with reduced activity tolerance. We systematically reviewed randomized controlled trials (RCTs) that explored interventions to improve physical activity among patients with diabetes to establish whether co-morbid chronic pain was captured at baseline or explored as an effect modifier and if trials reported a component designed to target chronic pain.

Methodology/principal Findings

We searched CINAHL, Cochrane Central Registry of Controlled Trials, EMBASE, ERIC, MEDLINE, SPORTDiscus and PsycInfo from inception of each database to March 2012 for RCTs that enrolled patients with diabetes and randomly assigned them to an intervention designed to promote physical activity. Two reviewers independently selected trials and abstracted data. We identified 136 trials meeting our inclusion criteria, only one of which that reported capturing chronic pain measures at baseline. No trial reported on specific interventions to address chronic pain as a competing demand, or as an effect modifier.

Conclusion/significance

Only 1 trial identified that aimed to promote physical activity among patients with diabetes reported that co-morbid chronic pain was captured at baseline. No trials reported exploring chronic pain as an effect modifier or targeting it as part of its intervention.