OBJECTIVE: To describe epidemiological, clinical and magnetic resonance imaging findings of osteonecrosis in the distal femur and proximal tibia. MATERIALS AND METHODS: Evaluation of 19 patients (12 women and 7 men), with no previous history of causative factors, with magnetic resonance imaging findings suggestive of osteonecrosis in the tibial plateau or femoral condyle. RESULTS: Osteochondral abnormalities were observed in 63.1% of the cases; in 73.6% of them, such abnormality was associated with ipsilateral meniscal lesion. Also, a significant association with bone marrow edema (grade III in 16 cases) was observed. CONCLUSION: Magnetic resonance imaging has demonstrated to be a noninvasive method with good sensitivity in the diagnosis of knee osteonecrosis as well as of associated lesions which are most frequently found in women (63% of cases).

Keywords: Osteonecrosis, Magnetic resonance imaging, Subchondral abnormalities

In 2003, the National Committee of Medical Residency established new criteria for the accreditation of Radiology and Imaging Diagnosis Residency programs. Although these rules represent an advance to the resident's training, other specific abilities and skills should be developed in order to keep up with the technical and scientific advances and with the new requirements of the career. The authors' present the must important competencies and skills that complement the radiologist's education and suggest a change in current programs so that the resident can acquire these competencies and skills.

Keywords: Medical residency, Radiology, Image diagnostic, Resident; Education

Objetivo: A principal utilidade da tomografia por emissão de pósitrons com 18-fluordeoxiglicose (FDG-PET) está no estadiamento do câncer de pulmão. Porém, ela também pode ser utilizada para diferenciar lesões pulmonares indeterminadas, mas seu impacto na ressecção cirúrgica de lesões benignas é desconhecido. O objetivo deste estudo foi comparar a prevalência de lesões benignas em toracotomias feitas por suspeição de câncer de pulmão, antes e após a introdução do FDG-PET, em um centro de referência de cirurgia torácica. Materiais e Métodos: Os autores analisaram, prospectivamente, uma base de dados cirúrgicos de todos os pacientes consecutivos submetidos a toracotomia por câncer de pulmão suspeito ou comprovado e compararam a prevalência de lesões benignas em dois grupos ao longo de dois anos consecutivos, respectivamente antes (grupo I) e depois (grupo II) da introdução da FDG-PET. Resultados: Ressecção cirúrgica foi feita em 1.233 pacientes durante o período do estudo. A prevalência de lesões benignas na cirurgia nos grupos I e II foi similar (44/626 e 41/607, ambas correspondendo a 7%), e também no grupo II, entre aqueles submetidos a FDG-PET e os restantes (21/301 e 20/306 respectivamente, ambos correspondendo a 7%). No grupo II, dos 21 pacientes com lesões benignas submetidos a FDG-PET, 19 tiveram um estudo falso-positivo (valor médio padrão de captação 5.3 [faixa 2.6–12.7]). Desses, respectivamente 13 e 4 pacientes tiveram broncoscopia não diagnóstica e biópsia transtorácica percutânea de pulmão antes da toracotomia. Não houve diferença na proporção de lesões benignas diferentes ressecadas entre o grupo I e aqueles submetidos a FDG-PET no grupo II. Conclusão: A introdução da FDG-PET não alterou a proporção de pacientes submetidos a toracotomia por lesões benignas, principalmente devido à avidez pelo isótopo de algumas lesões não malignas. Tais resultados falsos-positivos devem ser considerados nos casos em que se contempla a possibilidade de ressecção cirúrgica em pacientes com câncer de pulmão não confirmado.

Keywords: Tomografia por emissão de pósitrons; Tomografia computadorizada; Pulmão – lesões benignas ou congênitas; Câncer de pulmão – diagnóstico e estadiamento; Câncer de pulmão – cirurgia.

Knee pain is the most frequent symptom in osteoarthritis, a condition that is the leading cause of chronic disability in the elderly and one of the main sources of morbidity attributable to osteoarthritis in general. The causes of knee pain in individuals with osteoarthritis cannot be easily understood, and the knowledge of such causes is critical for determining future specific interventions. Bone attrition represents remodelling of the subchondral bone envelope in osteoarthritis, leading to a consequential change in bone shape and/or bone loss. However, bone attrition is not a feature that can be easily read, since it is hardly detected in the absence of clear defects of cortical bone integrity and because of overlap of bone structures at radiography. Bone attrition is associated not only with knee pain, but also with stiffness and disability. If attrition occurs prior to advanced osteoarthritis, this would suggest that changes in subchondral bone occur concurrently with cartilage loss and that treatments targeting cartilage loss alone are unlikely to be effective. Association with edemalike bone marrow lesions may be observed and constitute predictive factors for subchondral bone attrition. The present study was aimed at reviewing the literature, demonstrating the relevance of bone attrition and explaining how to diagnose this entity on imaging studies.

Keywords: Magnetic resonance imaging; Osteoarthritis; Knee pain; Bone attrition; Subchondral bone; Diagnosis.

OBJECTIVE: To show the morphometric patterns of lymph nodes of the head and neck, evaluating their number, shape, dimensions, hilum, and cortex, through the use of ultrasound examination of the neck. MATERIALS AND METHODS: We analyzed 400 right and left lymph nodes in a group of 20 healthy young and middle-aged individuals of both genders. RESULTS: In the ultrasound examination, we observed the following lymph nodes: mastoid; parotid (superficial, extraglandular, and intraglandular); submandibular (preglandular, retroglandular, and intracapsular); submental; and cervical (anterior and posterior). Although some individuals had up to seven lymph nodes in the same region, most had only two to three per region. The smallest lymph node diameter observed was 0.4 cm, and the largest was 2.7 cm. Most lymph nodes showed an elongated or oval shape. Most of the lymph node hila were echogenic, although a few were hyperechoic. However, the cortex was clearly hypoechoic in all of the lymph nodes evaluated. CONCLUSION: Ultrasound examination of healthy individuals allowed the characteristics of the lymph nodes of the head and neck to be observed clearly, which could provide a basis for the analysis of patients with diseases of these lymph nodes.

Keywords: Lymph nodes/anatomy & histology; Radiology; Diagnostic imaging.

OBJECTIVE: To assess the magnetic resonance imaging (MRI) patterns associated with central nervous system infection with Cryptococcus sp. in relation to patient immune status. MATERIALS AND METHODS: This was a retrospective study of MRI data for 19 patients with neurocryptococcosis who underwent the examination between January 2000 and March 2014. The MRI characteristics examined included lesion topography, aspects of diffusion, T1-weighted images, T2-weighted images, and contrast enhancement patterns. RESULTS: In all cases, cryptococcal infection was confirmed by cerebrospinal fluid analysis. Of the 19 patients, 10 were immunocompromised and 9 were immunocompetent. Abnormal imaging patterns occurred alone or in conjunction with other manifestations. The imaging patterns found in immunocompromised patients included the following: leptomeningeal enhancement, in 6; pachymeningeal enhancement, in 3 (due to intracranial hypotension in 2); perivascular space involvement, in 4; granulomas, in 2; hydrocephalus, in 2; miliary nodules, in 1; and plexitis, in 1. In immunocompetent patients, the following imaging patterns were observed: leptomeningeal enhancement, in 5; perivascular space involvement, in 3; granulomas, in 3; cryptococcoma, in 1; ventriculitis, in 1; and hydrocephalus, in 1. In 2 immunocompetent patients, diffusion-weighted imaging showed diffusion restriction in cerebral cryptococcal granuloma. CONCLUSION: In both groups, the most common imaging finding was leptomeningeal enhancement, followed by dilatation of perivascular spaces with the presence of mucoid material. Rare presentations, such as miliary nodules, plexitis, ventriculitis, and pachymeningeal enhancement, were also observed. None of the imaging patterns common to immunocompetent and immunocompromised patients differed significantly in frequency between them.

Keywords: Cryptococcosis/diagnostic imaging; Central nervous system infections/diagnostic imaging; Brain injuries/pathology; Magnetic resonance imaging; Diagnostic imaging; Meninges/pathology.

Historically, radiology has developed in a way that has increasingly distanced the radiologist from the patient. Currently, diagnostic imaging results are predominantly communicated through written reports. Written communication is not considered sufficient, verbal communication being essential for the performance of the modern radiologist to be considered satisfactory. However, a lack of preparation on the part of the radiologist when communicating the diagnosis, especially when it is not favorable (as is often the case in a cancer hospital), makes that conversation quite challenging. Studies conducted in other countries have demonstrated that there are a variety of opinions on the part of requesting physicians and patients regarding radiologist-patient communication, which can be explained by cultural differences. Although there is no rule regarding the best way to accomplish such communication, there are definitely incorrect ways. To bridge the gap between radiologists and patients and improve radiologist-patient communication, preparation of radiologists during their medical residency is fundamental. Therefore, it is important to address this question in Brazil. The objective of this study was to identify deeper discussions about the topic in the scientific literature. This analysis could help us map those involved and plan strategies to improve the ethical behavior of radiologists toward their patients.

Keywords: Radiology; Physician-patient relations; Diagnostic imaging; Ethics.

Snapping scapula syndrome manifests as an audible or palpable crackling during the sliding movements of the scapula over the rib cage, often perceived during physical or professional activities. It can be caused by morphological alteration of the scapula and rib cage, by an imbalance in periscapular musculature forces (dyskinesia), or by neoplasia (bone tumors or soft tissue tumors). In this pictorial essay, we review the main causes of snapping scapula syndrome, exemplified by a collection of didactic cases.

Keywords: Scapula; Joint diseases/diagnostic imaging; Shoulder.

Endometriosis is characterized by the presence of endometrial tissue outside the uterus. When endometrial implants penetrate more than 5 mm into the peritoneum, the condition is referred to as deep pelvic endometriosis. Although laparoscopy is the gold standard test to establish a diagnosis of deep endometriosis, transvaginal ultrasound represents an alternative that can contribute to detection of the disease, because it is an accessible, low-cost, noninvasive examination that allows preoperative planning in cases requiring surgical treatment. However, in clinical practice, transvaginal ultrasound is still not widely used as the first-line examination in suspected cases of endometriosis. This essay describes the findings of deep endometriosis on transvaginal ultrasound, in order to disseminate knowledge of the utility of the technique for the diagnosis of this disease.

Keywords: Endometriosis/diagnostic imaging; Ultrasonography/methods; Diagnostic techniques and procedures.

Sagittal balance describes the optimal alignment of the spine in the sagittal plane, resulting from the interaction between the spine and lower limbs, via the pelvis. Understanding sagittal balance has gained importance, especially in the last decade, because sagittal imbalance correlates directly with disability and pain. Diseases that alter that balance cause sagittal malalignment and may trigger compensatory mechanisms. Certain radiographic parameters have been shown to be clinically relevant and to correlate with clinical scores in the evaluation of spinopelvic alignment. This article aims to provide a comprehensive review of the literature on the spinopelvic parameters that are most relevant in clinical practice, as well as to describe compensatory mechanisms of the pelvis and lower limbs.

Keywords: Spine; Pelvis; Radiography; Lordosis/diagnostic imaging; Kyphosis/diagnostic imaging; Spinal curvatures/diagnostic imaging; Postural balance.

Coronavirus disease 2019 (COVID-19), which is caused by a new coronavirus—severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)—is a pandemic with major impacts on the health care sector, and a broad view of the disease is of fundamental importance for any radiologist. The purpose of this review is to address the main clinical and imaging aspects of COVID-19, as well as guidelines for requesting and using imaging methods; measures to protect patients and health care professionals; systems for quantifying pulmonary findings and preparing integrated reports; and the main innovations that have emerged during this pandemic.

Keywords: Coronavirus infection/diagnostic imaging; Coronavirus; Review.

Intracranial cystic lesions are common findings on neuroimaging examinations, arachnoid cysts being the most common type of such lesions. However, various lesions of congenital, infectious, or vascular origin can present with cysts. In this pictorial essay, we illustrate the main causes of non-neoplastic intracranial cystic lesions, discussing their possible differential diagnoses as well as their most relevant imaging aspects.

Keywords: Arachnoid cysts/diagnosis; Brain/diagnostic imaging; Cysts/diagnostic imaging; Epidermal cyst/diagnostic imaging; Magnetic resonance imaging.

Os nervos cranianos representam extensões das estruturas funcionais do cérebro que cruzam a cabeça e o pescoço. Eles estão ligados a diferentes estruturas cranianas e se relacionam com diversas doenças. Uma compreensão profunda de sua complexa anatomia e aparência normal de imagem permite ao examinador identificar e caracterizar com mais precisão as anormalidades. A ressonância magnética com contraste é uma importante ferramenta para avaliar essas estruturas, especialmente as sequências tridimensionais de precessão livre de estado estacionário, que proporcionam alta resolução espacial e de partes moles, apesar da fina espessura dos nervos cranianos. Na maioria dos casos, os achados de imagem são inespecíficos, e uma anamnese completa, exame físico dirigido e testes laboratoriais são necessários para estreitar o diagnóstico diferencial. Este ensaio iconográfico ilustra e discute doenças congênitas, traumáticas e vasculares dos nervos cranianos, mostrando imagens em uma abordagem fisiopatológica.

Keywords: Neuroimagem/métodos; Radiologia/métodos; Ressonância magnética/métodos; Nervos cranianos/diagnóstico por imagem.

Cystic echinococcosis (hydatid disease) is a zoonotic parasitic disease, caused by ingestion of Echinococcus granulosus eggs, that can result in cyst formation anywhere on the body. Hydatid disease is frequently seen in regions where there is human-animal contact and poor socioeconomic development. The prevalence of the disease ranges from 0 to 79 cases/100,000 population. Hydatid cysts are typically found in the liver and lungs, being less common in other parts of the body. Computed tomography or magnetic resonance imaging is often used in order to clarify the sites affected by a hydatid cyst, such as the cranial and thoracic regions, which also facilitates the surgical evaluation and minimizes complications. Although rare, hydatid cysts in atypical locations can provoke unusual complications, with unpredictable findings and symptoms. This essay discusses the radiological aspects of rare thoracic hydatid cysts.

Keywords: Echinococcosis/diagnostic imaging; Echinococcosis, pulmonary/diagnostic imaging; Thoracic diseases/diagnostic imaging; Tomography, X-ray computed; Magnetic resonance imaging.

Mucoceles of the appendix are rare and can have quite variable imaging and clinical presentations, sometimes mimicking an adnexal mass. The underlying cause can be neoplastic or non-neoplastic. The typical imaging appearance of a mucocele of the appendix is that of a cystic structure with a tubular morphology. This structure is defined by having a blind-ending and being contiguous with the cecum. Radiologists should be familiar with key anatomical landmarks and with the various imaging features of mucoceles of the appendix, in order to provide a meaningful differential diagnosis of a lesion in the right lower abdominal quadrant. In addition, a neoplastic mucocele can rupture, resulting in pseudomyxoma peritonei, which will change the prognosis dramatically. Therefore, prompt diagnostic imaging is crucial.

Keywords: Mucocele/diagnostic imaging; Appendiceal neoplasms/diagnostic imaging; Adenocarcinoma, mucinous/diagnostic imaging; Cystadenoma, mucinous/diagnostic imaging; Pseudomyxoma peritonei/etiology.