The use of signs or analogies for interpretation and description of medical images is an old and common practice among radiologists. Comparison of findings with animals, food or objects is not unprecedented and routinely performed. Many signs are quite specific and, in some cases, pathognomonic. Indeed, notwithstanding their degree of specificity, signs may help in the characterization of certain diseases. Several neuroradiological signs have been already described. The authors will present 15 neuroradiology signs in the present essay, approaching their main characteristics, the significance of their role in the clinical practice, as well as their respective imaging findings.

Keywords: Radiological signs; Neuroradiology; Computed tomography; Magnetic resonance imaging.

The use of signs for interpretation of images in neuroradiology is extremely useful. Some signs are quite specific and, in some cases, pathognomonic. In this second part of their essay, the authors describe 15 additional neuroradiological signs. Main characteristics of imaging findings will be approached and the significance of their role in the clinical practice will be discussed.

Keywords: Radiological signs; Neuroradiology; Computed tomography; Magnetic resonance imaging.

Breast cancer is one of the most prevalent cancers in women. Mammography is an excellent method with proven impact on breast cancer mortality reduction. Nevertheless, mammography is not a perfect method, with some weaknesses, especially in screening women with dense breasts, preoperative staging and treatment evaluation. Breast magnetic resonance imaging has shown the necessity and relevance of functional evaluation of breast lesions. The authors describe two methods of functional evaluation of breasts and describe their own experience with contrast-enhanced digital mammography and with breast-specific gamma imaging. Both methods are already available in our country and have shown promising results in the detection of mammographically occult lesions, confirmation of suspicious lesions and in the reduction of unnecessary biopsies and may supplement the weaknesses of mammography, particularly in the investigation of dense breasts.

Keywords: Mammography; Breast scintigraphy; Breast neoplasms; Magnetic resonance imaging.

OBJECTIVE: To assess the feasibility of contrast-enhanced spectral mammography (CESM) of the breast for assessing the size of residual tumors after neoadjuvant chemotherapy (NAC). MATERIALS AND METHODS: In breast cancer patients who underwent NAC between 2011 and 2013, we evaluated residual tumor measurements obtained with CESM and full-field digital mammography (FFDM). We determined the concordance between the methods, as well as their level of agreement with the pathology. Three radiologists analyzed eight CESM and FFDM measurements separately, considering the size of the residual tumor at its largest diameter and correlating it with that determined in the pathological analysis. Interobserver agreement was also evaluated. RESULTS: The sensitivity, specificity, positive predictive value, and negative predictive value were higher for CESM than for FFDM (83.33%, 100%, 100%, and 66% vs. 50%, 50%, 50%, and 25%, respectively). The CESM measurements showed a strong, consistent correlation with the pathological findings (correlation coefficient = 0.76–0.92; intraclass correlation coefficient = 0.692–0.886). The correlation between the FFDM measurements and the pathological findings was not statistically significant, with questionable consistency (intraclass correlation coefficient = 0.488–0.598). Agreement with the pathological findings was narrower for CESM measurements than for FFDM measurements. Interobserver agreement was higher for CESM than for FFDM (0.94 vs. 0.88). CONCLUSION: CESM is a feasible means of evaluating residual tumor size after NAC, showing a good correlation and good agreement with pathological findings. For CESM measurements, the interobserver agreement was excellent.

Keywords: Mammography/methods; Breast neoplasms/diagnosis; Magnetic resonance imaging; Neoadjuvant therapy/methods.