Detection of coronary artery calcification with nontriggered computed tomography of the chest

<div><p>Abstract Objective: To evaluate the accuracy of visual analysis and of the coronary artery calcium (CAC) score in nontriggered computed tomography (CT), in comparison with that of the CAC score in electrocardiogram-triggered CT, in identifying coronary calcification. Materials and Methods: A total of 174 patients for whom CT was indicated for CAC scoring underwent nontriggered and triggered CT in a 64-channel multislice scanner, in a single session without a change in position. The images were interpreted by a radiologist with seven years of experience in thoracic and cardiovascular radiology. The measurement of coronary calcium was carried out by three methods: CAC score with dedicated software in nontriggered CT, CAC score with dedicated software in triggered CT, and visual analysis without dedicated software in nontriggered CT. Results: In nontriggered CT, the CAC score presented an accuracy of 95.98% (95% CI: 91.93-98.04). The visual analysis showed an accuracy of 97.13% (95% CI: 93.45-98.77). Conclusion: Nontriggered CT showed excellent accuracy in the identification and exclusion of coronary calcification, either the CAC score was determined with dedicated software or through visual analysis.</p></div

Effects of blood glucose level on 18F-FDG uptake for PET/CT in normal organs: A systematic review

<div><p>Purpose</p><p>To perform a systematic review of the effect of blood glucose levels on 2-Deoxy-2-[18F]fluoro-D-glucose (18F-FDG) uptake in normal organs.</p><p>Methods</p><p>We searched the MEDLINE, EMBASE and Cochrane databases through 22 April 2017 to identify all relevant studies using the keywords “PET/CT” (positron emission tomography/computed tomography), “standardized uptake value” (SUV), “glycemia,” and “normal.” Analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations. Maximum and mean SUVs and glycemia were the main parameters analyzed. To objectively measure the magnitude of the association between glycemia and 18F-FDG uptake in different organs, we calculated the effect size (ES) and the coefficient of determination (<i>R</i>²) whenever possible.</p><p>Results</p><p>The literature search yielded 225 results, and 14 articles met the inclusion criteria; studies included a total of 2714 (range, 51–557) participants. The brain SUV was related significantly and inversely to glycemia (ES = 1.26; <i>R</i>² 0.16–0.58). Although the liver and mediastinal blood pool were significantly affected by glycemia, the magnitudes of these associations were small (ES = 0.24–0.59, <i>R</i>² = 0.01–0.08) and negligible (<i>R</i>² = 0.02), respectively. Lung, bone marrow, tumor, spleen, fat, bowel, and stomach 18F-FDG uptakes were not influenced by glycemia. Individual factors other than glycemia can also affect 18F-FDG uptake in different organs, and body mass index appears to be the most important of these factors.</p><p>Conclusion</p><p>The impact of glycemia on SUVs in most organs is either negligible or too small to be clinically significant. The brain SUV was the only value largely affected by glycemia.</p></div

Congenital Zika syndrome and neuroimaging findings: what do we know so far?

<div><p>Abstract Although infection with the Zika virus was first recognized in 1942, it received little attention until 2007, when a true pandemic spread throughout Africa, Asia, and the Americas. Since then, numerous forms of central nervous system involvement have been described, mainly malformations related to congenital infection. Although the neuroimaging findings in congenital Zika syndrome are not pathognomonic, many are quite suggestive of the diagnosis, and radiologists should be prepared to interpret such findings accordingly. The objective of this article is to review the computed tomography and magnetic resonance imaging findings in congenital Zika syndrome.</p></div

Study characteristics.

<p>Study characteristics.</p

Organ-specific analysis of the association between glycemia and SUVmax/mean.

<p>Organ-specific analysis of the association between glycemia and SUVmax/mean.</p

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow diagram.

<p>Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow diagram.</p

The usefulness of chemical-shift magnetic resonance imaging for the evaluation of osteoid osteoma

<div><p>Abstract Objective: The purpose of this study was to determine whether chemical-shift magnetic resonance imaging (MRI) could be useful in the diagnosis of osteoid osteoma when clinical and radiological tumor features are inconclusive. Materials and Methods: This retrospective study included 17 patients who underwent chemical-shift MRI for the evaluation of osteoid osteoma. For all patients, two musculoskeletal radiologists independently recorded signal intensities on in-phase and out-of-phase images in the nidus of the tumor, in abnormal-intensity bone marrow surrounding the lesion, and in normal-appearing bone marrow. For each region, relative signal intensity ratios were calculated by dividing out-of-phase by in-phase values. Relative ratios > 1 were considered indicative of neoplastic lesions. Statistical analysis was carried out to analyze the sample. Inter-observer and intra-observer agreement for each imaging method were assessed using intraclass correlation coefficients according to the Fleiss method and a value > 0.65 was considered to indicate substantial agreement. Results: The mean relative signal intensity ratios were 1.2 (range, 0.9-1.4) for the nidus and 0.35 (range, 0.11-0.66) for the surrounding tissue; these values differed significantly from the relative signal-intensity ratios for normal-appearing bone marrow (p < 0.05). Conclusion: Chemical-shift MRI is useful for the diagnosis and evaluation of osteoid osteoma.</p></div

Facebook as a tool to promote radiology education: expanding from a local community of medical students to all of South America

<div><p>Abstract Objective: To assess the feasibility of Facebook to promote a radiology education project and to expand it from our university community of medical students to a wider audience. Materials and Methods: A group of 12 medical students created a Facebook page in June 2015, to contribute to radiology education in our university. From August 2015, clinical cases, including a brief explanation of clinical findings, along with different imaging modalities, were posted weekly and subscribers were encouraged to choose the most appropriate diagnosis. All cases were followed by the appropriate answer and an explanation to highlight imaging findings and diagnosis. Aiming to reach a larger audience, we also shared cases to a public Latin-American Facebook group, comprising a collective total of 28,182 physicians and medical students. Using the Facebook Insights tracking tool, we prospectively analyzed subscriber interaction with our page for 14 months. Results: During the period analyzed, 35 cases were posted. The most common imaging modalities were X-ray (n = 15) and computed tomography (n = 13). Before we began posting the weekly cases, our page had 286 likes. By October 2016, that number had grown to 4244, corresponding to an increase of 1484% and eight times the size of the medical student community at our institution (n = 530). Medical students made up most (76%) of the subscribers, followed by radiology residents (6%). An excellent or moderate contribution to personal image interpretation skills was reported by 65.3% and 33.1% of the users, respectively. Conclusion: Creating a Facebook page and posting weekly clinical cases proved to be an effective method of promoting radiology education.</p></div

ADC values (x 10⁻³ mm²/sec) of metastasis, benign solid lesions and cysts.

<p>CI: Confidence interval.</p

Classification of liver lesions based on clinical data.

<p>FNH: Focal nodular hyperplasia.</p