Resumen:

Abstract

Objective: The classification system of the thyroid nodules (TN) TI-RADS (Thyroid Imaging Reporting and Data System) proposed by Horvath et al. in 2009 is rarely used. The aim of this study was to evaluate a score modified according to ultrasound (US) criteria for malignancy in order to obtain a better application of this classification in daily practice. Materials and methods: 3650 TNs were classified according to a score of potential malignancy. US criteria for suspected malignancy were defined according to published studies and guidelines from various medical international societies. Each criterion was assigned a point for the final score of malignant probability of the TN. If suspected cervical lymph nodes were detected, a point was added.
Results: The score in all benign (TI-RADS 2) or probably benign (TI-RADS 3) thyroid nodules was zero. In the TI-RADS 3 group only 2.2% of the TNs were malignant. The scores of TI-RADS 4a, 4b and 4c were one, two and three to four points, respectively. The malignancy rates were 9.5%, 48% and 85%, respectively. TI-RADS 5 TN had a score of five or more points with a malignancy of 100% in this study. Conclusion: A TI-RADS classification based on a score according to the number of suspicious US criteria defined for malignancy can be applied in daily practice.

Keywords: Thyroid nodule; TI-RADS; Ultrasound; Thyroid scintigraphy.

Resumen:

Objetivo:
Demostrar la utilidad de la ecografía Doppler en la detección de la invasión vesical en el percretismo placentario.
Materiales y métodos:
Se evaluó por ecografía, desde noviembre de 2011 hasta mayo de 2013,a 21 pacientes de entre 20 y 44 años que tenían diagnóstico quirúrgico e histopatológico de acretismo placentario (AP).
Se consideró invasión vesical a la presencia de estructuras vasculares parietales en la evaluación Doppler color, mientras que se estableció como probable invasión a la presencia de otros hallazgos ecográficos sin señal Doppler.
Resultados:
De las 21 pacientes con acretismo placentario, 7 presentaron afectación vesical en el examen histopatológico: 5 tuvieron diagnóstico e informe ecográfico de invasión vesical (por la detección de estructuras vasculares en la evaluación Doppler color) y en las 2 restantes se planteó una probable afectación. De las 14 pacientes sin afectación vesical en el resultado histopatológico, hubo 7 con informes normales en la ecografía y 7 con resultados probables.
Conclusión:
La ecografía Doppler es un método muy útil para la detección de la invasión vesical en el percretismo placentario. Esta se observa con una vascularización parietal positiva en el Doppler color.

Palabras clave:
Placenta acreta; Placenta percreta; Ecografía.

Abstract
Purpose:
To demonstrate the usefulness of Doppler ultrasound in the detection of bladder invasion in cases of placenta percreta.
Materials and methods:
Twenty-one patients, aged 20-44 years old, with surgical and histopathological diagnosis of placenta accreta were evaluated by ultrasound between November 2011 and May 2013. The presence of increased vascularity on the bladder wall on Doppler ultrasound was classified as bladder invasion, while the presence of other sonographic findings on grayscale imaging with negative Doppler signal was classified as probable invasion.
Results:
Of the 21 patients included in the study with placenta accreta, 7 had bladder invasion on histopathological examination. Out of these 7, 5 had a diagnosis and ultrasound report of bladder invasion (due to the identification of vascular structures on color Doppler examination) and the remaining two were considered to have probable invasion. Of the 14 patients with no bladder invasion detected on histopathological examination, 7 had normal ultrasound reports and 7 were reported as probable invasion.
Conclusion:
Doppler ultrasound is a very reliable method for the detection of bladder invasion in placenta percreta, seen as increased vascularity of the uterine-bladder interface on color Doppler examination.

Key Words:
Placenta accret; placenta percreta; ultrasound.

Resumen:

El hidroenema TC es una técnica hibrida que que combina un agente de contraste negativo administrado por vía endorectal e imágenes de abdomen y pelvis de alta resolución adquiridas preferentemente con un tomógrafo multidetector y tras la administración de contraste endovenoso. El doble contraste que forman las interfases que se producen por la hipodensidad del agua en la luz, la pared del colon con tinción tras la administración de contraste endovenoso y la hipodensidad de la grasa pericolonica permiten la detección de pequeños engrosamientos tumorales. Las indicaciones actuales de dicha técnica son la búsqueda de un cáncer colónico en el caso de simatología digestiva después de una colonoscopía incompleta o en casos de contraindicaciones a la colonoscopía, el hallazgo inicial en tomografía de metástasis hepáticas, pacientes añosos o frágiles con sintomatología colónica y en evaluación pre-quirúrgica de un cáncer para realizar una estadificación clínica TNM. El rendimiento diagnóstico de este examen para el diagnóstico de una neoplasia se estima con una sensibilidad del 98,6% y un valor predictivo negativo de 99,1%. La estadificación pre-quirúrgica clínica TNM tiene una excelente sensibilidad.

Palabras clave: Hidroenema TC, cáncer colon, estadificación.

Abstract:
Hydroenema CT is a hybrid that combines the administration of endorectal negative contrast agent and high resolution images of the abdomen and pelvis, acquired preferably with a multidetector CT scanner after intravenous contrast injection. The two interfaces produced by the low density of water into the lumne, the colon wall staining after intravenous contrast injection, and the low density of pericolonic fat form a double contrast that enables the detection of slight thickening of tumors. This technique is currently indicated to find colonic cancer after an incomplete colonoscopy; when there are contraindications to colonoscopy, in cases of TC initial findings of hepatic metastases; when elder patients present colonic symptoms; or in pre-surgical TNM clinical staging. The performance of this test for neoplasm diagnosis is estimated to have a sensitivy of 98,6% and a negative predictive value of 99,1%. Pre surgical TNM clinical staging also has an excellent sensitivy.
Key Words:
Hydroenema CT, colonic cancer, staging.

Resumen:

Las Variantes Anatómicas (VA) del Polígono de Willis (PW) deben ser identificadas ya que su presencia es relevante en procedimientos quirúrgicos y por su asociación con aneurismas. La Angio-Resonancia Magnética (ARM) es un método no invasivo que permite identificarlas y determinar la forma con la que se presentan las Variantes Anatómicas del PW y subtipos, destacándose su utilidad en el estudio de las VA.
De un total de 190 pacientes, se observaron sin VA: 122(64%); con VA:68(36%). VA encontradas: Fenestración de ACoA:2 (3%). Duplicación de ACoA: 2(3%). ACA Ácigos: 3 (4%). Triple ACA: 1: (2%). Ausencia de A1:4 (6%). Bifurcación precoz de ACM: 3(4%).
Duplicación de ACoP: 1 (2%).Fenestración de ACP: 1(%). Origen fetal de ACP: 17(25%). Ausencia/hipoplasia de ACoP: 11(16%). Hipoplasia AICA/PICA: 15 (22%). Duplicación de ACS: 2(3%). Nacimiento conjunto de ACS+ACP: 2(3%). Trigeminal persistente: 4(6%).
La ARM cerebral es un excelente método para la detección de VAPW.
La variante mas frecuente fue el origen fetal de ACP.


Key Words:
Polígono de Willis, arterias intracraneales, variantes anatómicas, angiografía, resonancia magnética, aneurismas.

Abstract
The Anatomical Variations (AV) of the Circle of Willis (CW) must be identified since their presence is relevant in surgical procedures and their association to aneurysms. Magnetic Resonance Angiography (MRA) is a noninvasive method that permits the identification and determination of the way in which the Anatomical Variations of the CW appear and their subtypes. There is emphasis in its usefulness for the study of AV.
From a total of 190 patients, 122 (64%) did not have AV; 68 (36%) had AV. AV found: Fenestration of ACoA: 2 (3%). Duplicaction of ACoA: 2 (3%). Azygos ACA: 3(4%). Trifurcated ACA: 1 (2%). Absence of A1: 4 (6%). Early bifurcation of MCA: 3 (4%). Duplication of PCoA: 1 (2%). Fenestration of PCA: 1 (1%). Fetal origin of PCA: 17 (25%).
Absense/Hypoplasia of PCoA: 11 (16%). AICA/PICA hypoplasia: 15 (22%). Duplication of SCA: 2(3%). Joint origin of SCA and PCA: 2(3%).Persistent primitive trigeminal artery: 4 (6%).
The Cerebral MRA is and excellent method for the detection of AV of the CW. The most frequent variation was the fetal origin of PCA.

Key Words:
Circle of Willis, intracraneal arteries, anatomical variations, angiography, magnetic resonance, aneurysms.

Resumo:

Objective: To establish reference intervals for the fetal cisterna magna volume by means of two-dimensional (2D) method using the multiplanar mode of three-dimensional ultrasonography.
Materials and Methods:
Cross-sectional study with 224 healthy pregnant women between the 17th and 29th gestational weeks. The volume was automatically obtained by multiplying the three major axes in axial and sagittal planes by the constant 0.52. Polynomial regression was utilized to establish the correlation between fetal cisterna magna volume and gestational age, with adjustments by coefficient of determination (R2). Reliability and agreement were obtained by intraclass correlation coefficient (ICC) and limits of agreement, respectively.
Results:
Mean fetal cisterna volume with the 2D method ranged from 0.71 ± 0.19 cm 3 to 4.18 ± 0.75 cm 3 at the 17th and 29th weeks, respectively. The authors observed a good correlation between fetal cisterna magna volume and gestational age (R2= 0.67),excellent intraobserver reliability and agreement with ICC = 0.89 and limits of agreement 95% (–52.0; 51.8), respectively, and low interobserver reliability and agreement with ICC = 0.64 and limits of agreement 95% (–110.1; 84.6), respectively.
Conclusion: Reference intervals for fetal cisterna magna volume by means of 2D method using the multiplanar mode of three-dimensional ultrasonography were established and presented excellent intraobserver reliability and agreement.

Keywords: Fetus; Cisterna magna; Reference intervals; Two-dimensional ultrasonography; Three-dimensional ultrasonography.

Resumo:

Multiparametric MR (mpMR) imaging is rapidly evolving into the mainstay in prostate cancer (PCa) imaging. Generally, the examination consists of T2-weighted sequences, diffusion-weighted imaging (DWI), dynamic contrast-enhanced (DCE) evaluation, and less often proton MR spectroscopy imaging (MRSI). Those functional techniques are related to biological properties of the tumor, so that DWI correlates to cellularity and Gleason scores, DCE correlates to angiogenesis, and MRSI correlates to cell membrane turnover. Th e combined use of those techniques enhances the diagnostic confidence and allows for better characterization of PCa. The present article reviews and illustrates the technical aspects and clinical applications of each component of mpMR imaging, in a practical approach from the urological standpoint.

Resumen:

Abstract:
Trauma is the leading cause of death in pediatric patients older than 1 year, with abdominal trauma accounting for 10% of causes of death. Hollow viscera injuries are less than 1%, however its mortality is 20% in the case of intestinal perforation. Computed tomography is the method of choice for the identification and quantification of abdominal trauma injuries, given its excellent performance for solid viscera injuries, with less sensitivity in hollow visceral injuries, so that in the latter a high clinical suspicion and thorough analysis of the images by radiologists is important. A retrospective review was conducted of the findings in pediatric patients, with a history of blunt abdominal trauma, referred to computed tomography. The main findings on computed tomography suggestive of hollow visceral injury were: extraluminal air, extravasation of contrast medium, the presence of free intraperitoneal fluid, sentinel clot adjacent to the affected loop and thickening of the bowel wall.

Key Words:
Abdomen, Bruising, Computed tomography, Hollow viscera, Intestine, Pediatrics, Trauma.

Resumen:

Abstract:

The galaxy sign represents a mass-like lesion, composed of innumerable coalescing granulomatous nodules, more concentrated in the center than at the periphery. It was initially described in patients with sarcoidosis, and was referred to as the “sarcoid galaxy” sign. It is now known to be present in other entities such as tuberculosis, lung cancer and the pulmonary fibrosis mass of pneumoconiosis. Its identification and adequate interpretation is important, given that in association with other tomographic signs it allows an orientation toward the diagnosis of sarcoidosis.
Key Words:
Granuloma, Sarcoidosis, Tuberculosis.

Resumen:

Summary

Acute appendicitis is the most common cause of acute abdominal pain which requires surgery. Before the advent of modern diagnostic imaging techniques, the diagnosis of acute appendicitis was exclusively performed by clinical findings; however, the negative appendectomy rates decreased significantly after the introduction of sectional images such as computed tomography (CT), magnetic resonance imaging (MRI) and ultrasonography (US), as well as the morbidity and mortality associated with this disease. In this paper, we review the anatomy of the appendix, the clinical manifestations of acute appendicitis and the findings of this entity in different diagnostic imaging modalities based on available evidence.

Key words: Appendicitis, Appendectomy, Ultrasonography, Magnetic resonance, Imaging Tomography, X-ray computed.

Resumen:

Abstract

Introduction:At the present day the use of high resolution transducers have allowed significant progress in characterizing skin lesions, providing anatomical information such as size, depth, vascularization, calcium deposits, cyst or solid contents and even hair.
Objective: the objective of this article is to review the ultrasound characteristics of skin lesions, like: infections, tumors, and traumas.
Methodology: for its methodology, we use ultrasound images of outpatients seen at our institution.
Conclusion: we conclude that ultrasound is a useful tool that provides additional clinical information for the management of multiple skin lesions.

Key words: Ultrasonography, Epidermal cyst, Carcinoma, basal cell, Lipoma, Biopolymers, Pilonidal sinus, Silicone gels.

Resumen:

Abstract:
The presence of hyperintense punctiform images in the white matter in T2-weighted magnetic resonance (MR) sequences is a very common finding and is occasionally a diagnostic challenge for the radiologist. The present article attempts, using an anatomical approach to the brain circulation, as well as from histopathology correlation studies,to simplify the task of interpreting these images from the description of the three main patterns of hyperintense punctiform images in the white matter: vascular pattern, which corresponds to microvascular lesions; perivascular pattern, which represents inflammatory disease of which the paradigm is multiple sclerosis; and a non-specific pattern, which has to be a microvascular disease. From the various semiological elements in the MR images, a predominant pattern can be determined in each case and, in this way, helps in the differential diagnosis.

Keywords: White matter; Magnetic resonance; Leukoaraiosis; Multiple sclerosis; CADASIL; Vasculitis.

Resumen:

Abstract:

The Seventh Edition of the TNM classification for non-small cell bronchogenic carcinomas includes a series of changes in the T and M descriptor, in particular a re-classification of malignant pleural and pericardial effusions and of separated tumor nodes,new tumour size cutoff values and sub-divisions of the T1-T2 and M1 categories. We review these corrections that led to the changes in the staging system that affects stages II-III.Furthermore,we describe and illustrate the role of the different imaging techniques in tumour staging (CT, PET, PET-CT and MRI), highlighting their respective indications, advantages and disadvantages, as well their complementary function.

Key Words: Non-small cell bronchogenic carcinoma; Diagnostic imaging; Computed tomography; Positron-emission tomography; Magnetic resonance.

Resumen:

Abstract:
Objectives: To define diagnostic performance of magnetic resonance cholangiography (MRC) at the Clinic Center (Hospital de Clínicas) and to compare it with data reported in international bibliography.
Methods: A retrospective study was undertaken; 1 26 MRC examinations were done to 126 patients within the period December 2010 July 2013.The results were correlated with endoscopic retrograde cholangiopancreatography (ERCP), surgical findings and clinical outcome.
Results:These MRC examinations were evaluated for sensitivity (S),specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV). Regarding general biliary tract pathology, S amounted to 97%, Sp to 83%, PPV to 73% and NPV, to 98%; in patients with clinical suspicion for lithiasis the values found were 94% for S, 81% for Sp, 65% for PPV, and 97% for NPV. The incidence of anatomical variants was found to be 17.5%.
Conclusion: MRC was shown to perform well as a diagnostic procedure for common bile duct(CBD) pathology and choledocholithiasis in our center. S values, as well as NPV ones,agreed with values reported elsewhere.

Keywords: magnetic resonance cholangiography, biliary tract, choledocholithiasis.

Resumen:

Abstract:
Objetives: To describe the variations of cerebral arterial blood flow related to the circle of Willis, excluding those related to the persistence of basilar carotid and to the skull base anastomosis. Clinical relevance, characteristics and incidence from the data provided by the literature will be evaluated.
Methods: A retrospective observavational descriptive analysis of all circle of Willis angiotomographys performed in the hospital of Tacuarembó, during a period from december 1st 2009 until august 31 st 2013 was made. In cases in wich relevant normal variationes were identified, 3D and MIP reconstruccions were performed, allowing a correct anatomical description of them. The data relating to the prevalence and association with other anomalies and aneurysms were taken from the literature.
Results: The most common variants found in our study are linked to the PCA and to the A1 segment of ACA, wich is consistent with the literature.
Conclusions: The circle of Willis presents variations in its anatomy in 60% of the cases. Some of them have clinical relevance in relation to an increase in the incidence of aneurysms and malformations, in relation to oclusive events and surgical planing, so it is essencial to recognize them.

Resumen:

Abstract:

Purpose:
To determine the usefulness of alternative nodule size thresholds in a population undergoing computed tomo graphic (CT) screening for lung cancer and to compare the reported International Early Lung Cancer Action Pro gram (I-ELCAP) results with the National Lung Screening Trial (NLST) results.
Materials and Methods:
The institutional review board approved this retrospective analysis. Informed consent was obtained according to HIPAA compliance. Findings in the CT cohort in the NLST of 25 813 participants who underwent baseline CT in 2002–2004 were reviewed. The frequency of solid and part-solid pulmonary nodules and the lung cancer diagnoses using an alternative nodule threshold of 5.0, 6.0,7.0, 8.0, and 9.0 mm were determined. Proportional reduction in the frequency of positive results and their 95% confidence intervals using each of the alternative thresh olds were calculated.
Results:
The frequency of positive results in the baseline round in the CT arm of the NLST using the definition of a positive result of any parenchymal, solid or part-solid, noncalcified nodule of 5.0 mm or larger was 15.8% (4080 of 25 813). Using alternative thresholds of 6.0, 7.0, 8.0, and 9.0 mm, the frequencies of positive results were 10.5% (2700 of 25 813, 7.2% (1847 of 25 813), 5.3% (1362 of 25 813), and 4.1% (1007 of 25 813), respectively, and the corresponding proportional reduction in additional CT scans would have been 33.8% (1380 of 1480), 54.7% (2233 of 4080), 66.6% (2718 of 4080), and 73.8% (3013 of 4080), respectively. Concomitantly, the proportion of lung cancer diagnoses determined within the first 12 months would be delayed up to 9 months for 0.9% (two of 232), 2.6% (six of 232), 6.0% (14 of 232), and 9.9% (23 of 232) of the patients, respectively.
Conclusion:
The NLST results are similar to those previously reported for the I-ELCAP and suggest that, even for high-risk participants in the NLST, higher thresholds of nodule size should be considered and prospectively evaluated.

Abstract:

Abstract:

Paradoxical embolism (PDE) is an uncommon cause of acute arterial occlusion that may have catastrophic sequelae. The possibility of its presence should be considered in all patients with an arterial embolus in the absence of a cardiac or proximal arterial source. Despite advancements in radiologic imaging technology,the use of various complementary modalities is usually necessary to exclude other possibilities from the differential diagnosis and achieve an accurate imaging-based diagnosis of PDE. In current practice, the imaging workup of a patient with symptoms of PDE usually starts with computed tomography (CT) and magnetic resonance (MR) imaging to identify the cause of the symptoms and any thromboembolic complications in target organs (eg,stroke, peripheral arterial occlusion, or visceral organ ischemia). Additional imaging studies with modalities such as peripheral venous Doppler ultrasonography (US), transcranial Doppler US, echocardiography, and CT or MR imaging are required to detect peripheral and central sources of embolism, identify cardiac and/ or extracardiac shunts, and determine whether arterial disease is present. To guide radiologists in selecting the optimal modalities for use in various diagnostic settings, the article provides detailed information about the imaging of PDE, with numerous radiologic and pathologic images illustrating the wide variety of features that may accompany and contribute to the pathologic process. The roles of CT and MR imaging in the diagnosis and exclusion of PDE are described, and the use of imaging for planning surgical treatment and interventional procedures is discussed.