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1.
Background and objectivePsychometrics is a simple, intuitive approach used in educational research and in multiple-choice questionnaires. Since 2009, the competitive examination through which access to residency programs in Spain is determined (MIR) has included questions related to radiological images. The objective of this paper is to show the results of the psychometric analysis of these questions with the aim of comparing their degree of difficulty, discriminative capacity, and internal structure with respect to those of the other questions on the examination.Material and methodsWe analyzed all questions on the examination since 2009, classifying them as clinical cases with and without radiological images, clinical cases with and without non-radiological images, multiple choice questions, and negative questions. We used classical test theory and item response theory to assess the difficulty and degree of discrimination of the questions.ResultsOf 225 questions, between 11% and 15% of the questions included in the examinations were associated with images. The questions associated with radiological images were more difficult (corrected difficulty index, 0.51) and had worse discriminative capacity. The increased difficulty of radiological questions was associated with worse discriminative capacity, especially if the clinical information provided was inadequate or if the clinical information was contrary to the radiological concept or if there had never been any questions about the concept in previoous MIR examinations.ConclusionsTo equalize the standards of the MIR examination, it is necessary to maintain an appropriate structure in devising radiology questions, with terms from the clinical context, appropriate use of distracters, and a lower level of difficulty, which could be achieved by using radiological images with typical radiological findings.  相似文献   

2.
Imaging in oncology is an essential tool for patient management but its potential is being profoundly underutilized. Each of the techniques used in the diagnostic process also conveys functional information that can be relevant in treatment decision making. New imaging algorithms and techniques enhance our knowledge about the phenotype of the tumor and its potential response to different therapies. Functional imaging can be defined as the one that provides information beyond the purely morphological data, and include all the techniques that make it possible to measure specific physiological functions of the tumor, whereas molecular imaging would include techniques that allow us to measure metabolic changes. Functional and molecular techniques included in this document are based on multi-detector computed tomography (CT), 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET), magnetic resonance imaging (MRI), and hybrid equipments, integrating PET with CT (PET/CT) or MRI (PET-MRI). Lung cancer is one of the most frequent and deadly tumors although survival is increasing thanks to advances in diagnostic methods and new treatments. This increased survival poises challenges in terms of proper follow-up and definitions of response and progression, as exemplified by immune therapy-related pseudoprogression. In this consensus document, the use of functional and molecular imaging techniques will be addressed to exploit their current potential and explore future applications in the diagnosis, evaluation of response and detection of recurrence of advanced NSCLC.  相似文献   

3.

Objective

To analyze whether there are significant differences in the objective quantitative parameters obtained in the postprocessing of dual-energy CT enterography studies between bowel segments with radiologic signs of Crohn's disease and radiologically normal segments.

Material and methods

This retrospective study analyzed 33 patients (16 men and 17 women; mean age 54 years) with known Crohn's disease who underwent CT enterography on a dual-energy scanner with oral sorbitol and intravenous contrast material in the portal phase. Images obtained with dual energy were postprocessed to obtain color maps (iodine maps). For each patient, regions of interest were traced on these color maps and the density of iodine (mg/ml) and the fat fraction (%) were calculated for the wall of a pathologic bowel segment with radiologic signs of Crohn's disease and for the wall of a healthy bowel segment; the differences in these parameters between the two segments were analyzed.

Results

The density of iodine was lower in the radiologically normal segments than in the pathologic segments [1.8 ± 0.4 mg/ml vs. 3.7 ± 0.9 mg/ml; p<0.05].The fat fraction was higher in the radiologically normal segments than in the pathologic segments [32.42% ± 6.5 vs. 22.23% ± 9.4; p<0.05].

Conclusion

There are significant differences in the iodine density and fat fraction between bowel segments with radiologic signs of Crohn's disease and radiologically normal segments.  相似文献   

4.
5.
The greater temporal resolution provided in ultrafast dynamic contrast-enhanced magnetic resonance imaging sequences makes it possible to know the physiological phenomenon of the distribution of the contrast material through a time-signal intensity curve. Analyzing these curves enables us to deduce information relevant to the vascularization and perfusion of tissues, capillary permeability, and the interstitial space in the tumor. A steep curve with early washout in a space-occupying lesion greatly increases the possibility of histological malignancy, although this type of curve is not rare in benign lesions and relatively flat curves are not rare in malignant tumors. Nevertheless, dynamic studies of the uptake of contrast material provide important information for the characterization of neoplasms that, together with the usual signs, can help to differentiate between benign and malignant tumors of adipocyte, chondroid, or neural lineage, clearing up diagnostic uncertainty in certain benign lesions such as osteoid osteoma and ischemic musculoskeletal disease. Furthermore, it enables the accurate determination of the response to chemotherapy, detecting recurrence within the treated tumor early, delimiting more precisely the margins between the tumor and peritumoral edema, and helping in diagnostic planning by determining the most vascularized areas of the tumor, which are more likely to be malignant.  相似文献   

6.
《Radiologia》2016,58(5):373-379
ObjectiveTo retrospectively evaluate the efficacy and safety of percutaneous radiofrequency ablation (RFA) done to treat renal tumors in patients with high surgical risk or with the risk of developing multiple renal tumors in the medium term at our center over a period of 10 years.Material and methodsBetween 2005 and 2015, we used RFA to treat 89 T1a or T1b tumors in 87 patients (mean age, 73.7 ± 10.87 years) with high surgical risk. We excluded patients treated with radiofrequency and embolization or microwave ablation. The tumors treated were clear cell carcinomas (43.6%), papillary renal carcinomas (17.2%), chromophobe renal cell carcinomas (10.3%), cystic tumors (2.2%), and an angiomyolipoma (1.1%). The mean size of the tumors was 2.6 cm. Computed tomography and/or ultrasonography were used to guide the procedure. We analyzed the relation between the efficacy of the procedure and patients’ age, the type of needle, the source of the patients, the size and location of the tumor, and the number of sessions required to achieve ablation. We recorded all complications.ResultsThe RFA procedure was completed in all patients. The mean follow-up period was 32.1 months. The efficacy was 93.7%. A single session was sufficient in 87.5% of patients; 8% required two sessions and 4.5% required three sessions. The only factor associated with worse efficacy was the size of the tumor (p = 0.03). The rate of complications was 5.6%.ConclusionsRFA is efficacious and safe, with results comparable to those reported in the literature.  相似文献   

7.
《Radiologia》2021,63(6):495-504
ObjectiveInitial COVID-19 reports described a variety of clinical presentations, but lower respiratory abnormalities are most common and chest CT findings differ between adult and pediatric patients. We aim to summarize early CT findings to inform healthcare providers on the frequency of COVID-19 manifestations specific to adult or pediatric patients, and to determine if the sensitivity of CT justifies its use in these populations.MethodsPubMed was searched for the presence of the words “CT, imaging, COVID-19” in the title or abstract, and 17 large-scale PubMed and/or Scopus studies and case reports published between January 1, 2020 and April 15, 2020 were selected for data synthesis.ResultsInitial CT scans identified ground-glass opacities and bilateral abnormalities as more frequent in adults (74%, n = 698, and 89%, n = 378, respectively) than children (60%, n = 25, and 37%, n = 46). At 14+ days, CT scans evidenced varied degrees of improvement in adults but no resolution until at least 26 days after the onset of flu-like symptoms. In pediatric patients, a third (n = 9) showed additional small nodular GGOs limited to a single lobe 3-5 days after an initial CT scan.ConclusiónEarly adult CT findings suggest the limited use of CT as a supplemental tool in diagnosing COVID-19 in symptomatic adult patients, with a particular focus on identifying right and left lower lobe abnormalities, GGOs, and interlobular septal thickening. Early pediatric CT findings suggest against the use of CT if RT-PCR is available given its significantly lower sensitivity in this population and radiation exposure.  相似文献   

8.
《Radiologia》2016,58(2):136-144
ObjectiveTo evaluate the results of percutaneous cholecystostomy for urgent treatment of acute cholecystitis, with the aim of identifying factors that predict survival. To analyze the recurrence of cholecystitis after catheter withdrawal in patients considered unsuitable candidates for delayed surgery, with the aim of identifying factors that predict recurrence.Material and methodsWe reviewed 40 patients who underwent percutaneous cholecystostomy in a two-year period. We analyzed survival during hospitalization in relation with fever, abdominal pain, leukocytosis, and C-reactive protein before and after the procedure. We analyzed the recurrence of cholecystitis after catheter withdrawal in patients considered unsuitable candidates for delayed surgery, as well as the influence of obstruction seen on cholangiography, age, sex, and comorbidities on the recurrence rate.ResultsDuring the hospital stay, 4 (10%) patients died of septic shock. Cholecystostomy improved fever, leukocytosis, and abdominal pain within five days of the procedure, but these improvements did not have a statistically significant effect on survival and were not therefore considered useful prognostic factors. Among the 15 patients considered unsuitable candidates for delayed surgery, 6 (40%) had recurrences of cholecystitis during a mean follow-up period of 6.7 months after catheter withdrawal. We found no association between recurrence and any of the parameters analyzed.ConclusionsOutcomes in our series of patients with high risk for surgery who underwent cholecystostomy for urgent treatment of acute cholecystitis were similar to those reported in other series. Withdrawing the catheter in patients considered unsuitable candidates for delayed surgery is not recommended due to the high risk of recurrence of cholecystitis in comparison with other series.  相似文献   

9.

Objective

To assess the usefulness of cardiac stress magnetic resonance imaging (MRI) with adenosine in the detection of ischemic heart disease in patients with a low pretest probability of disease.

Material and methods

We used the probability ratio to analyze the usefulness of cardiac stress MRI in a selection of patients with a low pretest probability of ischemic heart disease (low or moderate cardiovascular risk, atypical chest pain, or absence of prior ischemic heart disease).

Results

We included 295 patients followed up for a median of 28 (19-36) months. A total de 60 patients had an event. Cardiac stress MRI was more useful in patients with a low pretest probability: atypical chest pain (probability ratio [PR] positive 8.56), absence of prior ischemic heart disease (PR positive 4.85), and low or moderate cardiovascular risk (PR positive 3.87).

Conclusions

Cardiac stress MRI can be useful in the diagnosis of ischemic heart disease in patients with a low pretest probability.  相似文献   

10.
Background and aimsBibliometrics makes it possible to measure the relative importance of a scientific journal in its field. The current study analyzed the scientific publications in Radiología and the bibliometric parameters of the journal in the period comprising 2010 through 2019.Materials and methodsWe reviewed the bibliometrics for Radiología through information obtained from three sources: Scopus, the online version of the journal, and the publisher (Elsevier). We retrospectively analyzed aspects related to the editorial process (final decision and speed), the articles published (type, subspecialty of radiology, and imaging technique), the trends in citation and various indices(CiteScore, SNIP, and SJR), visibility, downloads, author characteristics (geographical origin and institutional collaboration), and the most cited articles.ResultsThe number of articles published in Radiología gradually decreased during the decade, and the time to publication increased. Original research articles account for the largest share of the articles published. The most common subject areas were radiology of the digestive tract and neuroradiology. Nevertheless, the bibliometric indicators and the number of downloads of articles increased every year. Regarding the authorship of the articles published, although authors from Spain predominate, the participation of authors from other countries became increasingly common. Collaboration among different institutions also became increasingly common in the period analyzed.ConclusionsThis review shows the progression of the journal's scientific work and some aspects that must be addressed to favor the growth of Radiología.  相似文献   

11.
《Radiologia》2016,58(2):129-135
ObjectiveTo analyze the usefulness of diffusion magnetic resonance (MR) sequences before and after prostatic artery embolization (PAE) in patients with benign prostatic hyperplasia (BPH).Material and methodsWe analyzed MR studies done before (7-10 days) and after (30 days) PAE in 19 patients with BPH treated with PAE between June 2012 and December 2013. We used 1.5 Tesla scanners with body surface coils. In pre-PAE MR studies, we recorded mean b40 values and minimum (min) and maximum (max) apparent diffusion coefficient (ADC) values. In post-PAE MR studies, we recorded b40, b400, and b1000 values and min, mean, and max ADC values. We compared diffusion behavior/ADC before and after PAE and areas without ischemia. We correlated these with decreased prostatic volume (PV).ResultsWe identified ischemia with contrast in 8 (42.1%) patients. No significant difference was found in mean b40 (p= 0.1650) or in the b40 ratio (p= 0.8868) between patients with ischemia and those without before PAE. Min b40, b40 ratio, and min ADC values differed significantly between ischemic areas and nonischemic areas within patients [p= 0.048 (b40 min and ratio) and p= 0.002 (min ADC)]. No significant correlation was found between the percentage decrease in PV and mean b40 (p= 0.8490) or b40 ratio (p = 0.8573).ConclusionPost-PAE ischemia generates objective changes in diffusion and ADC values that enable ischemic sectors to be differentiated from nonischemic sectors. Future studies should analyze whether it is possible to subjectively differentiate between these areas through the visualization of nonischemic sectors and the feasibility of replacing them with contrast to detect ischemia.  相似文献   

12.
《Radiologia》2014,56(6):524-532
ObjectivesTo evaluate the radiologic and pathologic responses to neoadjuvant chemotherapy and their correlation in the molecular subtypes of breast cancer and to analyze their impact in disease-free survival.Material and methodsWe included 205 patients with breast cancer treated with neoadjuvant chemotherapy. We evaluated the radiologic response by comparing MRI images acquired before and after chemotherapy. The pathologic response was classified on the Miller and Payne scale. For each subtype (HER2+, TN, luminal A, luminal B HER2–, and luminal B HER2+), we used the χ2 test, Student's t-test, ANOVA, and Kendall's Tau-b to evaluate the radiologic response and the pathologic response, the radiologic-pathologic correlation, and the disease-free survival.ResultsThe subtypes HER2+ (62.1%) and TN (45.2%) had higher rates of complete radiologic response. The pathologic response was 65.5% in the HER2+ subtype, 38.1% in the TN subtype, 2.6% in the luminal A subtype, 8.2% in the luminal B HER2– subtype, and 31% in the luminal B HER2+ subtype. The rate of radiologic-pathologic correlation was significant in all subtypes, higher in TN and HER2 (Tau-b coefficients 0.805 and 0.717, respectively). Disease-free survival was higher in HER2+ (91.9 ± 3.3 months) and lower in TN (69.5 ± 6.3 months), with significant differences between the cases with poor and good radiologic responses (P=.040). Survival was greater in cases with good radiologic response, except in cases with luminal A subtype.ConclusionMRI can be a useful tool that provides information about the evolution of breast cancer treated with neoadjuvant chemotherapy, which varies with the immunohistochemical subtype.  相似文献   

13.
《Radiologia》2019,61(6):489-497
Objectives1. To review the activity in our hospital's pediatric cardiac magnetic resonance imaging (cMRI) program from its inception to the present. 2. To evaluate changes in the number of patients, in the number of studies done under anesthesia, in the number of studies done with contrast material (magnetic resonance angiography (MRA) and delayed enhancement), and in representative diseases studied. 3. To estimate trends in the parameters evaluated in objective 2.Material and methodsThe pediatric cMRI program at our hospital started on February 14, 2005. We assessed cMRI studies done between the inception of the program and December 31, 2018. The cases were entered in a calculation table that included sex, date of birth, date of examination, clinical presentation, radiologic diagnosis, sequences done, and anesthesia. For each year, we obtained data about patients’ age, studies done under anesthesia, contrast-enhanced MRA, delayed enhancement studies, and postoperative studies. We also evaluated the evolution of the number of patients studied for a group of representative diseases (coarctation of the aorta; tetralogy of Fallot; dextro-transposition of the great arteries; corrections of univentricular heart; hypoplastic left heart syndrome; anomalous pulmonary venous return; and cardiomyopathy). We analyzed these data with bar graphs, evolutions of means, and logarithmic trend curves.ResultsA total of 2606 cases were included. The number of cases per year increased gradually. The mean age of all patients was 12.5 years, and the age of the patients studied also increased during the 14-year period. Anesthesia was used in 42%. Contrast-enhanced MRA was done in 57.6% and delayed enhancement in 42.13%. The most common condition was aortic coarctation (16.39%), although the frequency of aortic coarctation and hypoplastic left heart syndrome decreased slightly during the period. By contrast, the frequency of cardiomyopathy (7.25% of cases) increased slightly, to the point where it represented 9.35% in 2018.ConclusionDuring the 14-year period in which pediatric cMRI has been done at our hospital, the conditions studied, the type of patients, and the techniques used has varied; the number of patients and patients’ age has increased, where as the frequency of MRA studies has decreased. The prevalence of the different conditions studied has also changed.  相似文献   

14.
《Radiologia》2016,58(3):221-224
We carried out a critically appraised topic (CAT)-type study to determine whether the relevant scientific evidence supports the recommendation of doing a multiparametric magnetic resonance imaging study of the prostate in all patients who are candidates for prostate biopsy with the aim of improving the detection of clinically significant prostate cancer and stratifying patients to receive active surveillance or treatment. After a formal literature search and an analysis of the two most relevant articles it found, we reached the conclusion that, despite promising results that point to the potential usefulness of this approach, there is still not enough clear scientific evidence to endorse it categorically. Before this approach can be endorsed, we need evidence from well-designed prospective randomized trials using widely agreed upon criteria and including large numbers of patients at multiple centers.  相似文献   

15.
《Radiologia》2022,64(3):214-227
ObjectivesTo develop prognosis prediction models for COVID-19 patients attending an emergency department (ED) based on initial chest X-ray (CXR), demographics, clinical and laboratory parameters.MethodsAll symptomatic confirmed COVID-19 patients admitted to our hospital ED between February 24th and April 24th 2020 were recruited. CXR features, clinical and laboratory variables and CXR abnormality indices extracted by a convolutional neural network (CNN) diagnostic tool were considered potential predictors on this first visit. The most serious individual outcome defined the three severity level: 0) home discharge or hospitalization ≤ 3 days, 1) hospital stay >3 days and 2) intensive care requirement or death. Severity and in-hospital mortality multivariable prediction models were developed and internally validated. The Youden index was used for the optimal threshold selection of the classification model.ResultsA total of 440 patients were enrolled (median 64 years; 55.9% male); 13.6% patients were discharged, 64% hospitalized, 6.6% required intensive care and 15.7% died. The severity prediction model included oxygen saturation/inspired oxygen fraction (SatO2/FiO2), age, C-reactive protein (CRP), lymphocyte count, extent score of lung involvement on CXR (ExtScoreCXR), lactate dehydrogenase (LDH), D-dimer level and platelets count, with AUC-ROC = 0.94 and AUC-PRC = 0.88. The mortality prediction model included age, SatO2/FiO2, CRP, LDH, CXR extent score, lymphocyte count and D-dimer level, with AUC-ROC = 0.97 and AUC-PRC = 0.78. The addition of CXR CNN-based indices did not improve significantly the predictive metrics.ConclusionThe developed and internally validated severity and mortality prediction models could be useful as triage tools in ED for patients with COVID-19 or other virus infections with similar behaviour.  相似文献   

16.
《Radiologia》2022,64(1):26-40
Macrocephaly is a clinical term defined as an occipitofrontal circumference more than two standard deviations above the mean. It is present in 5% of children and is a common indication for imaging studies. There are multiple causes of macrocephaly; most of them are benign. Nevertheless, in some cases, macrocephaly is the clinical manifestation of a condition that requires timely medical and/or surgical treatment. The importance of imaging studies lies in identifying the patients who would benefit from treatment. Children with macrocephaly associated with neurologic alterations, neurocutaneous stigmata, delayed development, or rapid increase of the circumference have a greater risk of having disease. By contrast, parental macrocephaly is predictive of a benign condition. Limiting imaging studies to patients with increased risk makes it possible to optimize resources and reduce unnecessary exposure to tests.  相似文献   

17.

Objective

To explore the relationship between ventricular filling curves and the extent of late enhancement on cardiac magnetic resonance imaging (MRI) in patients with hypertrophic cardiomyopathy.

Material and methods

We retrospectively included consecutive patients with suspected and/or confirmed hypertrophic cardiomyopathy and a control group of patients matched for age and sex who underwent cardiac MRI with evaluation of late enhancement. Among other determinations, we evaluated the following parameters on cine sequences: peak filling rate, time to the first peak filling rate, and filling rate normalized to the filling volume.

Results

Late enhancement was observed in 29 (73%) of the 40 patients with hypertrophic cardiomyopathy. The normalized peak filling rate was significantly lower in patients with late enhancement (4.9  ±  1.6 in those with hypertrophic cardiomyopathy positive for late enhancement vs. 5.8  ±  2.2 in those with hypertrophic cardiomyopathy negative for late enhancement vs. 6.3  ±  1.5 in controls, p  =  0.008) and the time to peak filling was longer in patients with late enhancement (540.6  ±  89.7 ms vs. 505.5  ±  99.3 ms in those with hypertrophic cardiomyopathy negative for late enhancement vs. 486.9  ±  86.3 ms in controls, p  =  0.02). When the population was stratified into three groups in function of the normalized peak filling rate, significant differences were observed among groups for age (p  =  0.002), mean wall thickness (p  =  0.036), and myocardial mass (p  =  0.046) and atrial dimensions, whereas no significant differences with respect to late enhancement were seen.

Conclusions

In patients with hypertrophic cardiomyopathy, we found a significant association between ventricular filling patterns and age, wall thicknesses, and atrial dimensions, but not with the extent of late enhancement.  相似文献   

18.
ObjectiveTo describe the detection of cortical areas and subcortical pathways involved in language observed in MRI activation studies and tractography in a 3 T MRI scanner and to correlate the findings of these functional studies with direct intraoperative cortical and subcortical stimulation.Material and methodsWe present a series of 14 patients with focal brain tumors adjacent to eloquent brain areas. All patients underwent neuropsychological evaluation before and after surgery. All patients underwent MRI examination including structural sequences, perfusion imaging, spectroscopy, functional imaging to determine activation of motor and language areas, and 3D tractography. All patients underwent cortical mapping through cortical and subcortical stimulation during the operation to resect the tumor. Postoperative follow-up studies were done 24 hours after surgery.ResultsThe correlation of motor function and of the corticospinal tract determined by functional MRI and tractography with intraoperative mapping of cortical and subcortical motor areas was complete. The eloquent brain areas of language expression and reception were strongly correlated with intraoperative cortical mapping in all but two cases (a high grade infiltrating glioma and a low grade glioma located in the frontal lobe). 3D tractography identified the arcuate fasciculus, the lateral part of the superior longitudinal fasciculus, the subcallosal fasciculus, the inferior fronto-occipital fasciculus, and the optic radiations, which made it possible to mark the limits of the resection. The correlation with the subcortical mapping of the anatomic arrangement of the fasciculi with respect to the lesions was complete.ConclusionThe best treatment for brain tumors is maximum resection without associated deficits, so high quality functional studies are necessary for preoperative planning.  相似文献   

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