OBJECTIVE: The purpose of this study was to assess the performance of neutral oral contrast agents, comparing intestinal distention, distinction of intestinal wall, acceptance and side effects. MATERIALS AND METHODS: Prospective, randomized, and double-blinded study involving 30 patients who underwent computed tomography of abdomen and pelvis with administration of neutral oral contrast agents, divided into three groups according the contrast agent type: milk, water, and polyethylene glycol. The images were consensually analyzed by two observers, considering the degree of bowel distention and intestinal wall distinction. The patients responded to a questionnaire regarding the taste of the ingested solution and on their side effects. Kruskal-Wallis and chi-square tests were employed for statistical analysis. RESULTS: Among 40 studied intestinal segments, appropriate bowel distension (intestinal loop diameter > 2 cm) was observed in 14 segments (35%) in the milk group, 10 segments (25%) in the water group and 23 segments (57%) in the polyethylene glycol group (p = 0.01). Preparation with polyethylene glycol resulted in the best bowel distention, but it presented the worst taste and highest incidence of diarrhea as reported by patients. CONCLUSION: Bowel preparation with oral polyethylene glycol results in higher degree of bowel distention than with water or milk, but presents worst acceptance related to its taste and frequency of diarrhea as a side effect.

Keywords: X-ray computed tomography; Small bowel; Contrast media.

OBJECTIVE: To determine the number of punctures in fine-needle aspiration biopsies required for a safe cytological analysis of thyroid nodules. MATERIALS AND METHODS: Cross-sectional study with focus on diagnosis. The study population included 94 patients. RESULTS: The mean age of the patients participating in the study was 52 years (standard-deviation = 13.7) and 90.4% of them were women. Considering each puncture as an independent event, the first puncture has showed conclusive results in 78.7% of cases, the second, in 81.6%, and the third, in 71.8% of cases. With a view to the increasing chance of a conclusive diagnosis at each new puncture, two punctures have showed conclusive results in 89.5% of cases, and three punctures, in 90.6% of cases with at least one conclusive result. CONCLUSION: Two punctures in fine-needle aspiration biopsies of thyroid nodules have lead to diagnosis in 89.5% of cases in the study sample, suggesting that there is no need for multiple punctures to safely obtain the diagnosis of thyroid nodules.

Keywords: Thyroid nodules; Fine-needle aspiration biopsy; Ultrasonography-guided fine-needle aspiration.

OBJECTIVE: To evaluate mammographic breast density in asymptomatic menopausal women in correlation with clinical and sonographic findings. MATERIALS AND METHODS: Mammograms and clinical and sonographic findings of 238 asymptomatic patients were retrospectively reviewed in the period from February/2022 to June/2006. The following variables were analyzed: mammographic density patterns, sonographic findings, patients' age, parity, body mass index and use of hormone replacement therapy. RESULTS: Age, parity and body mass index showed a negative correlation with breast density pattern, while use of hormone replacement therapy showed a positive correlation. Supplementary breast ultrasonography was performed in 103 (43.2%) patients. Alterations which could not be visualized at mammography were found in 34 (33%) of them, most frequently in women with breast density patterns 3 and 4. CONCLUSION: The authors concluded that breast density patterns were influenced by age, parity, body mass index and time of hormone replacement therapy. Despite not having found any malignant abnormality in the studied cases, the authors have observed a predominance of benign sonographic abnormalities in women with high breast density patterns and without mammographic abnormalities, proving the relevance of supplementary ultrasonography to identify breast lesions in such patients.

Keywords: Mammogram; Breast density; Menopausal; Ultrasonography.

In imaging diagnosis, redundant nerve roots of the cauda equina are characterized by the presence of elongated, enlarged and tortuous nerve roots in close relationship with a high-grade lumbar spinal canal stenosis. This is not an independent entity, but it is believed to be a consequence of the chronic compression at the level of the lumbar canal stenosis and thus may be part of the natural history of lumbar spinal stenosis. The present paper is aimed at reviewing the histopathological, electrophysiological and imaging findings, particularly at magnetic resonance imaging, as well as the clinical meaning of this entity. As the current assessment of canal stenosis and root compression is preferably performed by means of magnetic resonance imaging, this is the imaging method by which the condition is identified. The recognition of redundant nerve roots at magnetic resonance imaging is important, particularly to avoid misdiagnosing other conditions such as intradural arteriovenous malformations. The literature approaching the clinical relevance of the presence of redundant nerve roots is controversial. There are articles suggesting that the pathological changes of the nerve roots are irreversible at the moment of diagnosis and therefore neurological symptoms are less likely to improve with surgical decompression, but such concept is not a consensus.

Keywords: Cauda equina; Spinal stenosis; Spine; Magnetic resonance imaging.

Computed tomography colonography is a minimally invasive method for screening for polyps and colorectal cancer, with extremely unusual complications, increasingly used in the clinical practice. In the last decade, developments in bowel preparation, imaging, and in the training of investigators have determined a significant increase in the method sensitivity. Images interpretation is accomplished through a combined analysis of two-dimensional source images and several types of three-dimensional renderings, with sensitivity around 96% in the detection of lesions with dimensions equal or greater than 10 mm in size, when analyzed by experienced radiologists. The present pictorial essay includes examples of diseases and pseudolesions most frequently observed in this type of imaging study. The authors present examples of flat and polypoid lesions, benign and malignant lesions, diverticular disease of the colon, among other conditions, as well as pseudolesions, including those related to inappropriate bowel preparation and misinterpretation.

Keywords: Colonography; Computed tomography; Colorectal neoplasm; Colonic polyps.

Lymphoma of the cervix is a rare disease. About 1.0% to 1.5% of extranodal lymphomas originates in the female genital tract. The clinical presentation of this condition is nonspecific and magnetic resonance imaging is important for diagnostic elucidation. The present report describes the case of a 80-year-old patient with lumbar pain, whose magnetic resonance imaging showed a large uterine mass. The final diagnosis was lymphoma.

Keywords: Lymphoma; Uterus.

Disc herniation with posterior epidural migration is a rare and often symptomatic entity. Multiple are the natural barriers that prevent this pattern of migration. Enhanced magnetic resonance imaging is the diagnostic modality of choice in these cases. The diagnostic dilemma in this case was the contraindication to the use of contrast since the patient was known to have chronic renal failure.

Keywords: Lumbar hernia; Complication; Epidural space; Posterior; Magnetic resonance imaging; Contrast.

Poland's syndrome is a rare non-inherited congenital anomaly. The authors describe the classic radiologic findings of Poland's syndrome by reporting the case of a male four-year old patient with asymmetry of hands and chest, illustrating the fundamental imaging criteria for a conclusive diagnosis.

Keywords: Poland's syndrome; Chest asymmetry; Congenital malformation.

Pelvic lipomatosis is a rare disorder where fat tissue deposition is observed in spaces of the pelvic area, causing extrinsic compression of the bladder, rectum and blood vessels. In the present report, the authors describe the case of a 48-year-old male patient presenting low back pain, dysuria and pollakiuria. Findings at excretory urography, computed tomography and magnetic resonance imaging are described.

Keywords: Pelvic lipomatosis; Urography; Computed tomography; Magnetic resonance imaging.

Renal lymphangiectasia is a rare condition characterized by parapyelic and perirenal fluid collections, which may progress from asymptomatic condition to chronic renal failure. The present report describes a case of incidental computed tomography finding of bilateral lymphangiectasia in an asymptomatic patient, as well as the main imaging findings with a comprehensive literature review.

Keywords: Renal lymphangiectasia; Renal lymphangiomatosis; Malformation; Lymphatic system; Kidney; Computed tomography.

New injectable fillers such as hyaluronic acid have recently been employed as a non-surgical alternative to implants such as silicone for aesthetic breast enhancement. Although their utilization is not yet widespread in Brazil, radiologists should be aware of the imaging findings in this context and of the implications of the presence of this filler for the radiological evaluation in the screening for breast cancer.

Keywords: Breast; Breast implants; Hyaluronic acid; Imaging diagnosis.

Epiphyseal fractures are frequently associated with knee trauma during sports in children and adolescents. Usually, Salter-Harris types I and II fractures are conservatively treated. However, failed closed reduction of displaced fractures suggest the presence of trapped periosteum, with indication for surgery. The present report describes a case of Salter-Harris type I fracture of the distal femur in a child, complicated with trapped periosteum detected at magnetic resonance imaging.

Keywords: Trapped periosteum; Physeal injury; Magnetic resonance imaging; Femur.