Machine learning and deep learning for classifying the justification of brain CT referrals.

OBJECTIVES: To train the machine and deep learning models to automate the justification analysis of radiology referrals in accordance with iGuide categorisation, and to determine if prediction models can generalise across multiple clinical sites and outperform human experts. METHODS: Adult brain computed tomography (CT) referrals from scans performed in three CT centres in Ireland in 2020 and 2021 were retrospectively collected. Two radiographers analysed the justification of 3000 randomly selected referrals using iGuide, with two consultant radiologists analysing the referrals with disagreement. Insufficient or duplicate referrals were discarded. The inter-rater agreement among radiographers and consultants was computed. A random split (4:1) was performed to apply machine learning (ML) and deep learning (DL) techniques to unstructured clinical indications to automate retrospective justification auditing with multi-class classification. The accuracy and macro-averaged F1 score of the best-performing classifier of each type on the training set were computed on the test set. RESULTS: 42 referrals were ignored. 1909 (64.5%) referrals were justified, 811 (27.4%) were potentially justified, and 238 (8.1%) were unjustified. The agreement between radiographers (κ = 0.268) was lower than radiologists (κ = 0.460). The best-performing ML model was the bag-of-words-based gradient-boosting classifier achieving a 94.4% accuracy and a macro F1 of 0.94. DL models were inferior, with bi-directional long short-term memory achieving 92.3% accuracy, a macro F1 of 0.92, and outperforming multilayer perceptrons. CONCLUSION: Interpreting unstructured clinical indications is challenging necessitating clinical decision support. ML and DL can generalise across multiple clinical sites, outperform human experts, and be used as an artificial intelligence-based iGuide interpreter when retrospectively vetting radiology referrals. CLINICAL RELEVANCE STATEMENT: Healthcare vendors and clinical sites should consider developing and utilising artificial intelligence-enabled systems for justifying medical exposures. This would enable better implementation of imaging referral guidelines in clinical practices and reduce population dose burden, CT waiting lists, and wasteful use of resources. KEY POINTS: Significant variations exist among human experts in interpreting unstructured clinical indications/patient presentations. Machine and deep learning can automate the justification analysis of radiology referrals according to iGuide categorisation. Machine and deep learning can improve retrospective and prospective justification auditing for better implementation of imaging referral guidelines.

Performance characteristics and predictors of temporal artery ultrasound for the diagnosis of giant cell arteritis in routine clinical practice in a prospective cohort.

OBJECTIVES: The diagnosis of giant cell arteritis (GCA) is primarily a clinical one. Temporal artery (TA) ultrasound (US) has been proposed as a new diagnostic tool. We aimed to assess the performance characteristics of TA US in routine clinical practice. METHODS: All patients presenting with suspected GCA to our institution are recruited to a prospective registry. Patients who had both a TA US and biopsy (TAB) performed at the time of presentation were included in the current study. The performance characteristics of TA US was compared to physician diagnosis at six months following presentation. Predictive factors for a positive TA US were explored in univariate and multivariable logistic regression analyses. RESULTS: 162 patients were included, 123 (76%) with GCA. Mean (SD) duration of glucocorticoid therapy was 6.6 days (19.4) at the time of TA US. TA US had a sensitivity of 52.8% (95%CI 43.7, 61.9) and specificity of 71.8% (95%CI 54.9, 84.5) for the diagnosis of GCA. Glucocorticoid duration did not significantly impact the results. A sequential strategy of TA US followed by TAB in the case of a negative US had a sensitivity of 78.9% (95%CI 70.1, 85.5) and specificity of 71.8% (95%CI 54.9, 84.5), equivalent to a simultaneous testing strategy. The only factor independently predictive of a positive TA US was male sex (OR 5.53, 95% CI 2.72 to 11.22, p<0.001). CONCLUSIONS: TA US is potentially useful in the diagnosis of GCA; however, interpretation of its results requires knowledge of the performance characteristics in the target population.

Diagnostic Utility of Computed Tomographic Angiography in Giant-Cell Arteritis.

Background and Purpose- The diagnosis of giant-cell arteritis (GCA) is challenging. Superficial temporal artery biopsy and ultrasound are positive in only 50%. We evaluated computed tomographic angiography (CTA) of the head in GCA. Methods- This case-control study was performed using a prospective GCA registry. Cases presented with stroke symptoms, had a CTA, and were subsequently diagnosed with GCA. Age- and sex-matched controls presented with stroke symptoms, had a CTA, and were not diagnosed with GCA. CTAs were evaluated for the presence of superficial temporal artery abnormalities. Results- Fourteen cases met the inclusion criteria and were matched with 14 controls. Blurred vessel wall margins and perivascular enhancement was found in 10 cases (71.4%) and 2 controls (14.3%). CTA has an accuracy of 78.6%, sensitivity of 71.4%, and a specificity of 85.7% for GCA. Conclusions- CTA detects superficial temporal artery abnormalities in GCA. This may facilitate early diagnosis and prompt implementation of potentially sight-saving and stroke-preventing treatment.

Clinical and genetic associations of radiographic sacroiliitis and its different patterns in psoriatic arthritis.

OBJECTIVES: We aimed to 1) identify clinical and genetic associations of sacroiliitis (SI) in patients with psoriatic arthritis (PsA), and 2) describe the different radiographic patterns of SI in PsA and their clinical and genetic associations. METHODS: 283 PsA patients, fulfilling CASPAR criteria, underwent detailed skin and rheumatologic assessments. In addition, HLA-B*27 and B*080101 status was recorded, which have been shown as the key genetic markers of radiographic SI in PsA. Grade 2 Unilateral or bilateral radiographic changes of SI were required for inclusion and involvement was further defined as asymmetrical or symmetrical. RESULTS: 70 patients (25%) had radiographic SI; all either with a present or past history of backache. Regression analysis demonstrated a significant association of SI with peripheral joint erosions (p=0.043), PASI maximum (p=0.041), younger age of PsA onset (p=<0.001), presence of HLA-B*0801 (p=0.002) and only marginal significance with HLA-B*2705 (p=0.059). Asymmetrical SI was noted in 51 patients (73%). In striking contrast to those patients with symmetrical SI, patients with asymmetrical SI were more likely to be female (p=0.04), have a trend towards more severe nail disease (p=0.08) and peripheral joint erosions (p=0.08), more osteolysis (p=0.01), more HLA-B*0801 positivity (p=0.001) and much less HLA-B*270502 positivity (p=<0.001). CONCLUSIONS: PsA developing at a younger age, severe skin disease, peripheral joint erosions, and HLA-B*0801 are significantly associated with SI, and there was only a marginal trend towards significance for HLA-B*2705. HLA-B*27 positive Axial-PsA patients resemble AS, while HLA-B*0801 positive Axial-PsA patients have asymmetrical and/or unilateral SI, which are typical of PsA.

Certain class I HLA alleles and haplotypes implicated in susceptibility play a role in determining specific features of the psoriatic arthritis phenotype.

OBJECTIVES: Psoriatic arthritis (PsA) susceptibility is associated with several different class I alleles, suggesting separate patterns of MHC effect. This exploratory study was based on the hypothesis that heterogeneity of the clinical phenotype of PsA might be explained by differing associations of clinical features with these susceptibility genes. METHODS: The clinical phenotype of 282 PsA patients in a cohort previously studied for associations with human leukocyte antigen (HLA)-B and HLA-C genotypes was first preliminarily assessed by univariate associations of susceptibility genes with specific clinical characteristics. To explore the potential genotypic effects of pairwise combinations of different HLA-B and C alleles/haplotypes, we created a series of allele/haplotype risk scores combining single alleles/haplotypes separately associated with being in the highest PsA severity propensity tertile based on the features studied by univariate analysis. RESULTS: In exploratory univariate analyses, B*27:05:02 was positively associated with enthesitis, dactylitis and symmetric sacroiliitis, whereas B*08:01:01-C*07:01:01and its component alleles were positively associated with joint fusion and deformities, asymmetrical sacroiliitis, and dactylitis. HLA-C*06:02:01 was negatively associated with asymmetrical sacroiliitis. The highest propensity score for severe PsA was with B*27:05:02-C*02:02:02, B*08:01:01-C*07:01:01 and B*37:01:01-C*06:02:01, but not the B*27:05:02-C*01:01:01 or B*57:01:01-C*06:02:01 haplotypes. In contrast, B*44 haplotypes were associated with presence of milder disease, and in univariate analysis with a decreased frequency of enthesitis, joint fusion, deformities and dactylitis. CONCLUSIONS: Different HLA susceptibility genes were associated with particular features that defined the PsA phenotype of a given patient. Additive interactions between different susceptibility HLA alleles defined the propensity for a more severe or milder musculoskeletal phenotype.

Striking difference of periarticular bone density change in early psoriatic arthritis and rheumatoid arthritis following anti-rheumatic treatment as measured by digital X-ray radiogrammetry.

OBJECTIVES: To examine changes in hand BMD as measured by digital X-ray radiogrammetry (DXR-BMD) in early PsA compared with RA patients prior to and 3 and 12 months after introducing an antirheumatic treatment. Further, to identify predictors for hand bone loss at the time of disease presentation. METHODS: Recent-onset, active, treatment-naïve patients were recruited. Clinical assessment, hand X-rays and DXR were obtained at 0, 3 and 12 months. Mean DXR-BMD for both hands and changes in DXR-BMD (mg/cm(2)/month) were compared between the two groups. We compared baseline disease characteristics of patients with normal hand DXR-BMD with those with bone loss. Logistic regression analyses were performed to identify predictors of hand BMD loss. RESULTS: A total of 64 patients were included. Hand DXR-BMD decreased in RA throughout the study (P = 0.043). Changes in periarticular bone density over 12 months differed between PsA and RA (P = 0.001). Hand bone loss at 3 months was associated with elevated BMI [odds ratio (OR) = 3.59, P = 0.041] and heavier alcohol intake (OR = 1.13, P = 0.035). Diagnosis of RA (OR = 57.48, P = 0.008), heavier alcohol intake (OR = 1.27, P = 0.012) and higher swollen joint count (SJC28) (OR = 1.5, P = 0.036) were independent predictors for hand bone loss in the first year. CONCLUSION: Following treatment, we found ongoing hand bone loss in RA and unchanged periarticular bone density in PsA, supporting the hypothesis that different pathomechanisms are involved in hand bone remodelling in PsA. Presence of RA, heavier alcohol intake and higher SJC were identified as independent predictors for hand bone loss over 1 year.

Cystic Fibrosis below the Diaphragm: Abdominal Findings in Adult Patients.

Cystic fibrosis (CF) is the most common lethal autosomal recessive disease in the white population. Mutation of the CF transmembrane conductance regulator gene on chromosome 7 results in production of abnormally viscous mucus and secretions in the lungs of patients with CF. A similar pathologic process occurs in the gastrointestinal tract, pancreas, and hepatobiliary system. Inspissated mucus causes luminal obstruction and resultant clinical and radiologic complications associated with the disease process. Pancreatic involvement can result in exocrine and endocrine insufficiency, pancreatic atrophy, fatty replacement, or lipomatous pseudohypertrophy. Acute and chronic pancreatitis, pancreatic calcification, cysts, and cystosis also occur. Hepatic manifestations include hepatic steatosis, focal biliary and multilobular cirrhosis, and portal hypertension. Biliary complications include cholelithiasis, microgallbladder, and sclerosing cholangitis. The entire digestive tract can be involved. Distal ileal obstruction syndrome, intussusception, appendicitis, chronic constipation, colonic wall thickening, fibrosing colonopathy, pneumatosis intestinalis, gastroesophageal reflux, and peptic ulcer disease have been described. Renal manifestations include nephrolithiasis and secondary amyloidosis. The educational objectives of this review are to reveal the abdominal manifestations of CF to facilitate focused analysis of cross-sectional imaging in adult patients. Life expectancy in patients with CF continues to improve because of a combination of aggressive antibiotic treatment, improved emphasis on nutrition and physiotherapy, and development of promising new CF transmembrane conductance regulator modulators. As lung function and survival improve, extrapulmonary conditions, including hepatic and gastrointestinal malignancy, will be an increasing cause of morbidity and mortality. Awareness of the expected abdominal manifestations of CF may assist radiologists in identifying acute inflammatory or neoplastic conditions. (©)RSNA, 2015.

Primary retroperitoneal masses: what is the differential diagnosis?

Primary retroperitoneal masses include a diverse, and often rare, group of neoplastic and non-neoplastic entities that arise within the retroperitoneum but do not originate from any retroperitoneal organ. Their overlapping appearances on cross-sectional imaging may pose a diagnostic challenge to the radiologist; familiarity with characteristic imaging features, together with relevant clinical information, helps to narrow the differential diagnosis. In this article, a systematic approach to identifying and classifying primary retroperitoneal masses is described. The normal anatomy of the retroperitoneum is reviewed with an emphasis on fascial planes, retroperitoneal compartments, and their contents using cross-sectional imaging. Specific radiologic signs to accurately identify an intra-abdominal mass as primary retroperitoneal are presented, first by confirming the location as retroperitoneal and secondly by excluding an organ of origin. A differential diagnosis based on a predominantly solid or cystic appearance, including neoplastic and non-neoplastic entities, is elaborated. Finally, key diagnostic clues based on characteristic imaging findings are described, which help to narrow the differential diagnosis. This article provides a comprehensive overview of the cross-sectional imaging features of primary retroperitoneal masses, including normal retroperitoneal anatomy, radiologic signs of retroperitoneal masses and the differential diagnosis of solid and cystic, neoplastic and non-neoplastic retroperitoneal masses, with a view to assist the radiologist in narrowing the differential diagnosis.

Incomplete atypical femoral fractures: assessing the diagnostic utility of DXA by extending femur length.

Atypical femoral fractures (AFFs) are associated with prolonged bisphosphonate therapy. A feature of incomplete AFF is a localized periosteal reaction. It has been suggested that extending the length of the femur image at the time of dual-energy X-ray absorptiometry (DXA) may diagnose an incomplete AFF. In patients older than 50 yr on bisphosphonate therapy for more than 5 yr, we extended femur length at the time of routine DXA. Abnormal DXA images were suggested in 19 of 257 patients (7.4%). On X-ray, 7 patients (2.7%) showed no abnormality, 7 patients (2.7%) showed evidence of AFF, and 5 patients (2.0%) showed an unrelated radiographic abnormality. Of the 7 cases with X-ray evidence of AFF, 5 had a periosteal flare and 2 had a visible fracture line, both of whom needed insertion of an intramedullary nail. We demonstrated that it is feasible to detect incomplete AFF early using extended femur length imaging with a prevalence in our sample of 2.7% (95% confidence interval: 1.7%-3.7%).

A simple method to rapidly assess the tibial tuberosity-trochlear groove distance using computed tomography.

BACKGROUND: The tibial tuberosity-trochlear groove (TTTG) distance is used to assess patellofemoral instability (PFI) and the likelihood of the development of patellofemoral disorders. The current gold standard in the assessment of the TTTG is computed tomography (CT) or magnetic resonance imaging (MRI). The current image software used for viewing these CT images does not allow for easy assessment of the TTTG. AIMS: This study presents a simple method to measure the TTTG on any image software, utilizing easily available and affordable stationary. METHODS: Four consecutive patients with no known knee pathologies were selected from recent studies at our institution. Their TTTGs were measured using this study's method and validated using the standard, freely available image analysis software Fiji. Pre-defined anatomical landmarks were located and marked using adhesive pieces of paper. The TTTG was defined as the distance between parallel lines through the apex of the tibial tuberosity and trough of the trochlear groove, where each of these lines is perpendicular to the Dorsal Condylar Line. RESULTS: The TTTG measured using this study's method was found to be in agreement with the measurements made using Fiji software. CONCLUSIONS: This study demonstrates that the TTTG can be simply and quickly assessed using readily available and affordable stationery, without the need for expensive or complex secondary analysis software. This could allow for the assessment of PFI in the outpatient clinic whilst the patient is present, offering valuable assistance to the orthopaedic surgeon in clinical decision making.

Tumor necrosis factor blocking therapy alters joint inflammation and hypoxia.

OBJECTIVE: To examine the effect of tumor necrosis factor (TNF) blocking therapy on hypoxia in vivo, macroscopic and microscopic inflammation, and magnetic resonance imaging (MRI) results in patients with inflammatory arthritis. METHODS: Patients with inflammatory arthritis (n = 20) underwent full clinical assessment, arthroscopy, synovial biopsy, and MRI before and after initiation of biologic therapy. Macroscopic synovitis/vascularity was assessed with a visual analog scale, and tissue PO(2) (tPO(2) ) was measured at arthroscopy using a Licox probe. Cell-specific markers (CD4, CD8, CD68, CD20, and CD19) and blood vessel maturity were quantified by immunohistologic analysis and dual-immunofluorescence factor VIII/α-smooth muscle actin staining, respectively. Contiguous gadoteric acid-enhanced MRI of the target knee was used to assess synovial enhancement. RESULTS: Biologic therapy responders showed a significant increase of tPO(2) in vivo (P < 0.05). This response was associated with significant reductions in 28-joint Disease Activity Score using the C-reactive protein level (DAS28-CRP) (P = 0.012), macroscopic synovitis (P = 0.017), macroscopic vascularity (P = 0.05), CD4+ T cells (P < 0.041), and CD68+ macrophages (P < 0.011). Blood vessel numbers were also reduced in responders; however, this did not reach statistical significance. Strong inverse correlations were demonstrated between changes in tPo(2) levels and changes in DAS28-CRP (r = -0.53, P < 0.001), CD4 (r = -0.44, P < 0.026), CD68 (r = -0.46, P < 0.003), and macroscopic vascularity (r = -0.314, P = 0.049) after therapy. Furthermore, changes in inflammation as measured by MRI showed a strong inverse correlation with tPO(2) levels (r = -0.688, P < 0.002) and positive correlations with CRP levels (r = 0.707, P = 0.001), macroscopic synovitis (r = 0.457, P = 0.056), macroscopic vascularity (r = 0.528, P= 0.017), CD4 (r = 0.553, P < 0.032), and CD68 (r = 0.670, P < 0.002) after therapy. CONCLUSION: This is the first study to show that successful biologic therapy significantly improves in vivo synovial hypoxia. Changes are strongly associated with changes in macroscopic and microscopic measures of joint inflammation and MRI improvement. These data further strengthen the concept that hypoxia is an important event driving synovial inflammation.

High bone turnover and hyperparathyroidism after surgery for tumor-induced osteomalacia: A case series.

Tumor-induced osteomalacia (TIO) is an ultrarare disorder that is caused by renal phosphate wasting due to uncontrolled tumoral production of fibroblast growth factor 23 (FGF23) from phosphaturic mesenchymal tumors. Surgical removal of the tumor is curative. There is limited information on the biochemical changes in mineral metabolism and bone remodeling activity after surgery, but it is reported that surgery is followed by a hungry bone syndrome (HBS) with hypocalcemia and secondary hyperparathyroidism. We report the biochemical response to surgery in two patients, who presented with severe TIO, as manifested by proximal myopathy, multiple stress fractures, high FGF23, low serum phosphate, low maximum renal phosphate reabsorption threshold (TmP/GFR), and low 1,25-dihydroxy-vitamin D (1,25(OH)2D). Prior to surgery, both patients developed secondary hyperparathyroidism and one case had progressed to tertiary hyperparathyroidism. After surgery there was normalization of FGF23, TmP/GFR, and phosphate. High 1,25(OH)2D was recorded. One patient had hypocalcaemia and worsening secondary hyperparathyroidism consistent with HBS; the other patient did not have hypocalcemia but had worsening tertiary hyperparathyroidism that only resolved with cinacalcet. There was a marked increase in bone remodeling markers, both resorption and formation, consistent with a high bone turnover state. There was a different pattern of change in bone specific alkaline phosphatase, reflecting healing of osteomalacia. Biochemical monitoring in the post-surgical management of TIO is warranted for guiding adjustments in medical intervention, both short-term and long-term. Future use of burosumab prior to surgery for TIO may ameliorate the immediate post-surgery effects.

Prostate cancer detection with magnetic resonance imaging (MRI)/ cognitive fusion biopsy: Comparing standard and targeted prostate biopsy with final prostatectomy histology.

INTRODUCTION: The use of multiparametric magnetic resonance imaging (MRI) with targeted biopsies of the prostate improves the diagnosis of clinically significant prostate cancer. Recent studies have shown that targeted prostate biopsies also more accurately predict final histopathology after radical prostatectomy (RP). There are three broad techniques for performing MRI-targeted prostate biopsy: cognitive MRI/ultrasound (US) fusion, software MRI/US fusion, and in-bore MRI-guided. Current practices recommend that a standard systematic 12-core prostate biopsy be performed, as well as targeted biopsies in patients with positive MRI findings. This study aimed to evaluate the accuracy of histological grading of cognitive MRI/US fusion prostate biopsy by comparing the histology from the targeted biopsy specimens (TB), standard systematic specimens (SB), and the combination of both (CB) specimens with the final histological grade from subsequent prostatectomy. METHODS: A retrospective, single-center review of 115 patients who underwent standard systematic and cognitive MRI/US-targeted biopsy of the prostate before undergoing a RP between 2016 and 2019 was performed. MRI findings, biopsy, final histology International Society of Urological Pathology (ISUP) grades, and patient demographics were collected. Cochran's Q test and McNemar test were used to compare the differences in upgrading, downgrading, and concordance between each biopsy group. RESULTS: The concordance between SB, TB, and CB biopsy were 28.7%, 49.6%, and 50.4%, respectively. There was no significant difference in concordance between TB and CB. Patients were more likely to be downgraded on the final histology when comparing CB with TB alone (26.1% vs. 16.5%, p<0.05). In cases where an ISUP grade 1 cancer was diagnosed on TB (n=24), there was a 62.5% chance that the final histology would be upgraded. In the same sample, when combined with a SB, the risk of upgrading on final histology was reduced to 37.5%. CONCLUSIONS: Although grading concordance between TB and CB were similar, the concomitant use of a SB significantly reduced the rate of upgrading in the final RP histopathology. CB may result in better decision-making regarding treatment options and also have implications for intraoperative planning.

The evolution of whole-body imaging.

This article reviews the evolution of whole-body imaging, discussing the history and development of radiography, nuclear medicine, computed tomography (CT), positron emission tomography (PET), combined PET-CT, and magnetic resonance imaging. The obstacles hindering progress toward whole-body imaging using each of these modalities, and the technical advances that were developed to overcome them, are reviewed. The effectiveness and the limitations of whole-body imaging with each of these techniques are also briefly discussed.

The Integration of Active Learning Teaching Strategies Into a Radiology Rotation for Medical Students Improves Radiological Interpretation Skills and Attitudes Toward Radiology.

PURPOSE: In recent years, there has been increased recognition of the benefits of teaching by active learning. However, there is a paucity of experimental studies utilizing active learning in undergraduate radiology rotations, which is traditionally a passive learning experience. We designed a new radiology rotation that integrated teaching by active learning. We prospectively examined the efficacy of this new rotation compared to our standard rotation in terms of students' radiological competency and attitudes toward radiology, as well as impact on departmental efficiency. METHODS: This was a prospective cohort study involving fourth year medical students completing a 1-week radiology rotation at our department between January and April 2018. One cohort completed a rotational model which incorporated active learning sessions (integrated cohort) while the remainder were taught using traditional passive learning methods (standard cohort). All participants completed a radiology examination before and after the rotation and were surveyed on their attitudes toward radiology. RESULTS: A total of 105 students enrolled in the study. The mean postrotation competency score obtained by the integrated cohort was significantly higher than that obtained by the standard cohort (82% vs 62%; P < 0.001). The integrated rotation freed up 7 hours of radiologists' time per week. While the students completing the integrated rotation had a more positive perception of radiology, they were no more likely to express a desire to pursue a career in radiology. CONCLUSIONS: The integration of active learning sessions into an undergraduate radiology rotation results in an improvement in students' postrotation radiological competency and attitudes toward radiology.

Recurrent pyogenic cholangitis: from imaging to intervention.

OBJECTIVE: The objective of this article is to familiarize the reader with the sonographic, CT, MR cholangiopancreatography, and ERCP appearances of recurrent pyogenic cholangitis and to briefly review the role of interventional radiology in the management of this disease. CONCLUSION: Recurrent pyogenic cholangitis is a complex disease, the incidence of which is increasing in Western countries. Radiologists should be aware of the role of imaging in the diagnosis of this disease and the use of imaging as a guideline for subsequent intervention.

Page kidney after renal allograft biopsy: sonographic findings.

The development of renal failure and hypertension due to extrinsic renal compression by hematoma in the subcapsular space is well-described and most commonly seen after blunt trauma. It may also occur as a complication of percutaneous renal biopsy, both in native kidneys and renal allografts, and is a rare cause of reversible allograft failure. We describe a case of Page kidney in renal transplantation after percutaneous biopsy causing allograft dysfunction. Early recognition with sonography is important if irreversible damage to the allograft is to be prevented.

Cardiac multidetector CT: technical and diagnostic evaluation with evidence-based practice techniques.

The "bottom-up" model of evidence-based practice (EBP) emphasizes the principles of integrating best research evidence with clinical expertise and patient values. It is derived from multidisciplinary sources, including clinical medicine, epidemiology, and adult learning theory, and has been applied to many medical disciplines, including radiology. Central to its implementation in everyday busy radiology practice is its emphasis on accurate, rapid modern informatics/internet to get the best current research evidence into everyday practice. In this article, the authors apply the principles of EBP to the topic of cardiac computed tomography. EBP is ideally suited to asking, searching, appraising, applying, and evaluating the literature on this rapidly developing technology.

Breast Arterial Calcification on screening mammography can predict significant Coronary Artery Disease in women.

INTRODUCTION: Breast Arterial Calcification (BAC) on digital mammography has been associated with an increased risk of Coronary Artery Disease (CAD). We aimed to investigate the association of BAC with findings on Coronary Computed Tomography Angiography (CCTA) within a cohort of women from the national breast screening program. METHODS: Symptomatic women (chest pain) aged between 50 and 65 who underwent a CCTA and who also had a screening mammography between 2014 and 2015 were recorded. BAC and CAD-RADS™: Coronary Artery Disease-Reporting and Data System were scored by separate blinded specialist radiologists. Cardiac risk factors were recorded. Patients' cardiac follow up (with Exercise Stress Test, Percutaneous Coronary Intervention or echocardiography) and cardio-protective medications were also documented. RESULTS: 219 eligible women underwent a CCTA. Of these, 104 patients also underwent digital mammography. Using standard linear regression BAC was identified as a significant predictor of CAD-RADs ≥3 disease. Using binomial logistic regression, BAC remained associated with CAD-RADs ≥3 (p=0.023). A significantly higher proportion of patients with BAC >1 were on cardio-protective medications (p=0.041) and had medications initiated or changed, or had further cardiac investigation (p=0.037 and p=0.019, respectively) than those with no BAC, after a mean follow-up of 20.6 (range 15-27) months. CONCLUSION: BAC diagnosed on 2 yearly screening mammography predicts CAD-RADs ≥3 disease in symptomatic patients.