Administración de contrastes intravenosos: las extravasaciones

Local extravasation of intravenous contrast material is a relatively common complication that radiologists need to know about. The risk of extravasation is greater in children, the elderly, and unconscious patients. Although most extravasations are mild and do not lead to further complications, some can result in severe lesions that require surgery, especially in cases that are associated with compartment syndrome. We describe the main characteristics of extravasations, comment on different treatments, and propose a protocol for dealing with them.     

Seudocavitación en las neoplasias de pulmón. ¿Permite predecir el diagnóstico de adenocarcinoma con crecimiento lepídico?

ObjectiveTo determine the prevalence of pseudocavitation in lung tumors and whether its presence makes it possible to predict the diagnosis of adenocarcinoma with lepidic growth.Material and methodsWe retrospectively reviewed chest CT studies for 212 consecutive lung tumors included in a CT perfusion database and for 351 consecutive adenocarcinomas diagnosed between July 2007 and September 2017.Two radiologists blinded to the pathology report determined whether air cysts were present in the tumors, excluding lesions with necrosis and those surrounded by bullae or emphysema.We analyzed whether the presence of pseudocavitation was associated with the histologic type, size, or EGFR positivity of the tumor as well as with the age or sex of the patient. We also evaluated the relationship with the histologic subtype of the tumor in patients who underwent surgery. We used the chi-square test for categorical variables and logistic regression for continuous variables.ResultsPseudocavitation was present in 15% of the tumors and was significantly more common in adenocarcinomas (24.1%), p = 0.003, although it was also observed in 9.8% of the epidermoid carcinomas and in 3% of the microcytic carcinomas. For the diagnosis of adenocarcinoma, the presence of pseudocavitation yielded 92.4% specificity, 24% sensitivity, 73.3% PPV, 58.4% NPV, and 37.6% accuracy.In the resected adenocarcinomas, 65% of the tumors with pseudocavitation had lepidic growth; the prevalence of pseudocavitation was 40.6% in tumors with lepidic growth, 31.5% in those with acinar growth, and 33% in those with papillary growth. Pseudocavitation was significantly more common in women (29%); no differences were found with respect to age, size, or EGFR positivity.ConclusionsPseudocavitation is more common in adenocarcinomas with lepidic growth and in women.     

¿Se debe realizar como primera prueba de imagen una radiografía de tórax en inspiración o en espiración ante la sospecha de neumotórax?

Chest radiography for pneumothorax screening is a frequently employed test. However, there is some controversy about which radiographic technique to choose. Posteroanterior chest radiography taken during expiration has been the technique used for many decades because several experts in classical thoracic radiology, such as Greene and Felson, recommended it. However, chest radiography, with posteroanterior and lateral projections, taken during deep breath is the appropriated technique to initially assess the whole thoracic pathology. In this review we have tried to establish, based on the best available evidence, which is the initial examination of choice to diagnose pneumothorax.     

Variación de tamaño de la hiperplasia nodular focal mediante resonancia magnética

ObjectiveTo evaluate the changes in the size of focal nodular hyperplasia (FNH) during long-term magnetic resonance imaging (MRI) follow-up.Material and methodsWe reviewed 44 FNHs in 30 patients studied with MRI with at least two MRI studies at least 12 months apart. We measured the largest diameter of the lesion (in mm) in contrast-enhanced axial images and calculated the percentage of variation as the difference between the maximum diameter in the follow-up and the maximum diameter in the initial study. We defined significant variation in size as variation greater than 20%. We also analyzed predisposing hormonal factors.ResultsThe mean interval between the two imaging studies was 35 ± 2 months (range: 12-94). Most lesions (80%) remained stable during follow-up. Only 9 of the 44 lesions (20%) showed a significant variation in diameter: 7 (16%) decreased in size and 2 (4%) increased, with variations that reached the double of the initial size. The change in size was not related to pregnancy, menopause, or the use of birth control pills or corticoids.ConclusionChanges in the size of FNHs during follow-up are relatively common and should not lead to a change in the diagnosis. These variations in size seem to be independent of hormonal factors that are considered to predispose.     

Manejo de la lesión renal focal incidental

Incidental renal lesions are relatively common in daily radiological practice. It is important to know the different diagnostic possibilities for incidentally detected lesions, depending on whether they are cystic or solid. The management of cystic lesions is guided by the Bosniak classification. In solid lesions, the goal is to differentiate between renal cancer and benign tumors such as fat-poor angiomyolipoma and oncocytoma. Radiologists need to know the recommendations for the management of these lesions and the usefulness of the different imaging techniques and interventional procedures in function of the characteristics of the incidental lesion and the patient's life expectancy.     

La tomografía computarizada de peñascos con dosis ultrabaja,utilizando filtro de estaño,detectores de alta resolución y reconstrucción iterativa,permite una adecuada valoración de las estructuras del peñasco

ObjectivesTo compare image quality and radiation dose in computed tomography (CT) studies of the petrous part of the temporal bone done with a scanner using a tin filter, high-resolution detectors, and iterative reconstruction versus in studies done with another scanner without a tin filter using filtered back projection.Material and methodsThis retrospective study compared CT studies in 32 patients who underwent ultralow-dose CT of the petrous part of the temporal bone in a 32-detector CT scanner (130 kV with a tin filter and iterative reconstruction) and in 36 patients who underwent the studies in a 16-detector CT scanner (120 kV and filtered back projection). We quantified the densities of muscle and bone tissues and background noise, and we calculated the signal-to-noise ratio. To evaluate image quality, two radiologists working independently subjectively evaluated the visualization of the different structures of the ear on a four-point scale (0=not visible; 3=perfectly identifiable and delimited), and we calculated the coefficient of interobserver concordance (k). Using commercial software, we quantified the effective dose of radiation at different anatomic levels with the dose-length product.ResultsIn the quantitative analysis, no significant differences were observed in background noise. In the qualitative analysis, the score on the subjective evaluation was similar or slightly lower for the delimitation of the different structures in the ossicular chain and cochlea in the studies done with the 32-detector scanner, with statistically significant differences. The mean effective dose of radiation was 0.16±0.04 mSv for the 32-detector scanner versus 1.25±0.30 mSv for the 16-detector scanner.ConclusionsUsing scanners with tin filters, high-resolution detectors, and iterative reconstruction makes it possible to obtain images with adequate quality for the evaluation of the structures of the petrous part of the temporal bone with ultralow doses of radiation (0.16±0.04 mSv).     

Ante la sospecha de abdomen agudo, ¿es necesario el contraste oral positivo en la tomografía computarizada?

The number of computed tomography studies done in emergency departments has increased substantially, and with this increase the controversy about whether positive oral contrast agents are necessary in all patients has also grown. The great image quality provided by multidetector computed tomography scanners, the increase in intraabdominal fat (as a natural element that provides contrast for separating the bowel loops) related with the increased prevalence of obesity in the population, and the potential drawbacks associated with the use of high-density oral contrast agents argue against the generalized us of these agents. This article aims to evaluate the effects of omitting the use of this type of oral contrast material for computed tomography examinations required in the emergency department for suspicion of acute abdominal pathology through an efficient literature search among recent publications.     

Ablación percutánea mediante radiofrecuencia de tumores renales en pacientes de alto riesgo: 10 años de experiencia

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.     

Dolor abdominal agudo en la enfermedad de Crohn. ¿Qué prueba de imagen urgente se debe hacer?

Crohn's disease is an autoimmune disease that predominantly affects the gastrointestinal tract. Crohn's disease is diagnosed at a young age and runs a chronic course with acute flare-ups. When patients with Crohn's disease present with flare-ups at the emergency department, they are usually managed in a way similar to patients with acute abdomen; there is no consensus about the most appropriate imaging work-up for patients with flare-ups of Crohn's disease. Thus, we decided to review the literature about the imaging tests indicated (whether related to their diagnostic performance or to lower exposure to ionizing radiation) for acute flare-ups in patients with Crohn's disease.     

Conocimientos en materia de radioprotección en radiólogos del noroeste de España

Objectives

To estimate radiologist? level of knowledge of and their implication in radioprotection.

Displasia fibrosa ósea. Aportación de la Medicina Nuclear al diagnóstico de sospecha de degeneración sarcomatosa

Fibrous dysplasia (FD) is a relatively frequent benign disease of the bone in which there is a maturation disorder of the bone-forming mesenchyme where the lamellar bone marrow is replaced with abnormal fibrous tissue. Its diagnosis is often an accidental finding when X-ray studies or bone scans are performed for other reasons since it is usually asymptomatic. There may be complications such as deformities, pathological fractures and exceptionally malignant transformation. The differential diagnosis between malignancy and FD can be complicated and lead to late diagnosis when sarcomatous degeneration already exists. In this context, the positron tomography with ¹⁸F-fluorodeoxyglucose (FDG-PET) may be useful in the monitoring of this condition. We present two cases of patients diagnosed of FD with suspicion of malignization of their bone lesions who were referred to Nuclear Medicin.     

¿Cómo preparar una comunicación oral y una conferencia?

The final aim of any scientific presentation is to transmit information clearly and effectively in a way that enables the members of the audience to assimilate it but also stimulates their intellects. The success of an oral presentation depends not only on the content of the presentation, but also on the speaker's skills in transmitting the information and making it attractive. To rise to the challenge posed by these objectives, presenters must work through different preparatory phases such as identifying the aims of the talk, preparing the contents of the talk, designing the presentation, and rehearsing the talk.This special article provides some useful recommendations for successful scientific presentations. It is intended for both new and experienced presenters.     

Síndrome de Cockett o de May-Thurner o síndrome de compresión de la vena ilíaca

Iliac vein compression syndrome (also known as May-Thurner syndrome or Cockett's syndrome) is a rare clinical entity in which the left common iliac vein is compressed when it passes between the right common iliac artery and the spine. The sustained compression and trauma caused by the pulsatile force of the artery on the vein damage the intima and lead to the formation of membranes or bands in the vascular lumen that hinder or obstruct the flow of blood in the vein, favoring thrombus formation. The current treatment strategy of choice is endovascular vein patch angioplasty and stenting with the aim of improving the caliber of the lumen and enabling normal venous drainage. We present two cases of May-Thurner syndrome and review the clinical and CT findings.     

Radiología en el estudio de la macrocefalia. ¿Por qué?, ¿cuándo?, ¿cómo?

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.     

Valoración del carcinoma urotelial de vías superiores mediante ecografía con contraste

Aim

To describe the findings and behaviour of contrast-enhanced ultrasound in the study of upper tract urothelial tumours and to assess its usefulness for diagnosis.