Histogram analysis in the differentiation between adrenal adenomas and pheochromocytomas: the value of a single measurement.

Objective: To assess the diagnostic accuracy of histogram analysis on unenhanced computed tomography (CT) for differentiating between adrenal adenomas and pheochromocytomas (PCCs). Materials and Methods: We retrospectively identified patients with proven PCCs who had undergone CT examinations between January 2009 and July 2019 at one of two institutions. For each PCC, we selected one or two adenomas diagnosed within two weeks of the date of diagnosis of the PCC. For each lesion, two readers scored the size, determined the mean attenuation, and generated a voxel histogram. The 10th percentile (P10) was obtained from the conventional histogram analysis, as well as being calculated with the following formula: P10 = mean attenuation - (1.282 × standard deviation). The mean attenuation threshold, histogram analysis (observed) P10, and calculated P10 (calcP10) were compared in terms of their diagnostic accuracy. Results: We included 52 adenomas and 29 PCCs. The sensitivity, specificity, and accuracy of the mean attenuation threshold were 75.0%, 100.0%, and 82.5%, respectively, for reader 1, whereas they were 71.5%, 100.0%, and 81.5%, respectively, for reader 2. The sensitivity, specificity, and accuracy of the observed P10 and calcP10 were equal for both readers: 90.4%, 96.5%, and 92.6%, respectively, for reader 1; and 92.3%, 93.1%, and 92.6%, respectively, for reader 2. The increase in sensitivity was significant for both readers (p = 0.009 and p = 0.005, respectively). Conclusion: For differentiating between adenomas and PCCs, the histogram analysis (observed P10 and calcP10) appears to outperform the mean attenuation threshold as a diagnostic criterion.

Objetivo: Avaliar a acurácia diagnóstica da análise por histograma na tomografia computadorizada (TC) sem contraste para a diferenciação entre adenomas adrenais e feocromocitomas (FCCs). Materiais e Métodos: Identificamos, retrospectivamente, pacientes com diagnóstico de FCC confirmado que foram submetidos a exames de TC entre janeiro de 2009 e julho de 2019 em duas instituições distintas. Para cada FCC, selecionamos um ou dois adenomas diagnosticados em até duas semanas da data do diagnóstico do FCC. Para cada lesão, dois leitores pontuaram o tamanho, determinaram a atenuação média e geraram um histograma com os voxels das imagens. O percentil 10 (P10) foi obtido a partir da análise convencional do histograma, além de ser calculado com a seguinte fórmula: P10 = atenuação média - (1,282 × desvio-padrão). O limiar de atenuação média, o P10 da análise por histograma (P10 observado) e o P10 calculado (P10calc) foram comparados em termos de acurácia diagnóstica. Resultados: Foram incluídos 52 adenomas e 29 FCCs. A sensibilidade, especificidade e acurácia do limiar de atenuação média foram de 75,0%, 100,0% e 82,5% para o leitor 1, respectivamente, e de 71,5%, 100,0% e 81,5% para o leitor 2, respectivamente. A sensibilidade, especificidade e acurácia do P10 observado e do P10calc foram idênticas para os dois leitores: 90,4%, 96,5% e 92,6%, respectivamente, para o leitor 1; e 92,3%, 93,1% e 92,6%, respectivamente, para o leitor 2. O aumento da sensibilidade foi significativo para ambos os leitores (p = 0,009 e p = 0,005, respectivamente). Conclusão: Para a diferenciação entre adenomas e FCCs, a análise por histograma (P10 observado ou P10calc) parece superar o limiar de atenuação média como critério diagnóstico.

Histogram analysis in the differentiation between adrenal adenomas and pheochromocytomas: the value of a single measurement / Análise por histograma para diferenciação entre adenomas da adrenal e feocromocitomas: o valor de uma medida única

Abstract Objective: To assess the diagnostic accuracy of histogram analysis on unenhanced computed tomography (CT) for differentiating between adrenal adenomas and pheochromocytomas (PCCs). Materials and Methods: We retrospectively identified patients with proven PCCs who had undergone CT examinations between January 2009 and July 2019 at one of two institutions. For each PCC, we selected one or two adenomas diagnosed within two weeks of the date of diagnosis of the PCC. For each lesion, two readers scored the size, determined the mean attenuation, and generated a voxel histogram. The 10th percentile (P10) was obtained from the conventional histogram analysis, as well as being calculated with the following formula: P10 = mean attenuation - (1.282 × standard deviation). The mean attenuation threshold, histogram analysis (observed) P10, and calculated P10 (calcP10) were compared in terms of their diagnostic accuracy. Results: We included 52 adenomas and 29 PCCs. The sensitivity, specificity, and accuracy of the mean attenuation threshold were 75.0%, 100.0%, and 82.5%, respectively, for reader 1, whereas they were 71.5%, 100.0%, and 81.5%, respectively, for reader 2. The sensitivity, specificity, and accuracy of the observed P10 and calcP10 were equal for both readers: 90.4%, 96.5%, and 92.6%, respectively, for reader 1; and 92.3%, 93.1%, and 92.6%, respectively, for reader 2. The increase in sensitivity was significant for both readers (p = 0.009 and p = 0.005, respectively). Conclusion: For differentiating between adenomas and PCCs, the histogram analysis (observed P10 and calcP10) appears to outperform the mean attenuation threshold as a diagnostic criterion.

Resumo Objetivo: Avaliar a acurácia diagnóstica da análise por histograma na tomografia computadorizada (TC) sem contraste para a diferenciação entre adenomas adrenais e feocromocitomas (FCCs). Materiais e Métodos: Identificamos, retrospectivamente, pacientes com diagnóstico de FCC confirmado que foram submetidos a exames de TC entre janeiro de 2009 e julho de 2019 em duas instituições distintas. Para cada FCC, selecionamos um ou dois adenomas diagnosticados em até duas semanas da data do diagnóstico do FCC. Para cada lesão, dois leitores pontuaram o tamanho, determinaram a atenuação média e geraram um histograma com os voxels das imagens. O percentil 10 (P10) foi obtido a partir da análise convencional do histograma, além de ser calculado com a seguinte fórmula: P10 = atenuação média - (1,282 × desvio-padrão). O limiar de atenuação média, o P10 da análise por histograma (P10 observado) e o P10 calculado (P10calc) foram comparados em termos de acurácia diagnóstica. Resultados: Foram incluídos 52 adenomas e 29 FCCs. A sensibilidade, especificidade e acurácia do limiar de atenuação média foram de 75,0%, 100,0% e 82,5% para o leitor 1, respectivamente, e de 71,5%, 100,0% e 81,5% para o leitor 2, respectivamente. A sensibilidade, especificidade e acurácia do P10 observado e do P10calc foram idênticas para os dois leitores: 90,4%, 96,5% e 92,6%, respectivamente, para o leitor 1; e 92,3%, 93,1% e 92,6%, respectivamente, para o leitor 2. O aumento da sensibilidade foi significativo para ambos os leitores (p = 0,009 e p = 0,005, respectivamente). Conclusão: Para a diferenciação entre adenomas e FCCs, a análise por histograma (P10 observado ou P10calc) parece superar o limiar de atenuação média como critério diagnóstico.

Independent external validation of nomogram to predict extracapsular extension in patients with prostate cancer.

INTRODUCTION: The objective of this study was to perform an independent external validation of the Giganti-Coppola nomogram (GCN), which uses clinical and radiological parameters to predict prostate extracapsular extension (ECE) on the final pathology of patients undergoing radical prostatectomy (RP). MATERIAL AND METHODS: Seventy-two patients diagnosed with prostate cancer (PCa), who were RP candidates from two institutions, were prospectively included. All patients underwent preoperative multi-parametric magnetic resonance imaging (mpMRI) at 1.5 T, without the use of an endorectal coil, with multiplanar images in T1WI, T2WI, DWI, and DCE. The AUC and a calibration graph were used to validate the nomogram, using the regression coefficients of the Giganti-Coppola study. RESULTS: The original nomogram had an AUC of 0.90 (p = 0.001), with a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 100%, 5.1%, 47.1%, 100%, and 48%, respectively. The calibration graph showed an overestimation of the nomogram for ECE. CONCLUSION: The GCN has an adequate ability in predicting ECE; however, in our sample, it showed limited accuracy and overestimated likelihood of ECE in the final pathology of patients with PCa submitted to RP. KEY POINTS: • Knowledge of preoperative local staging of prostate cancer is essential for surgical treatment. Extracapsular extension increases the chance of positive surgical margins. • Imaging modalities such as mpMRI alone does not have suitable accuracy in local staging. • Giganti-Coppola's nomogram achieved an adequate ability in predicting ECE.

Prognostic value of muscle depletion assessed by computed tomography for surgical outcomes of cancer patients undergoing total esophagectomy and gastrectomy.

INTRODUCTION: Considering the high morbimortality rate in oncologic surgeries of the gastrointestinal tract, especially in patients with malnutrition, the use of predictive tools is necessary, since preoperative strategies could improve postoperative outcomes. OBJECTIVES: To evaluate body composition by computed tomography and its association with morbimortality post esophagectomy and total gastrectomy. METHODS: Prospective cohort study (n = 80). Sociodemographic, diagnostic, treatment and postoperative data were collected. Anthropometric and biochemical (hemoglobin, transferrin, and albumin) data were evaluated. The muscle mass was calculated through two methods, the muscle mass index (MMI) and the psoas total area (PTA). For postoperative complications classification, the Clavien-Dindo scale was used. RESULTS: The prevalence of muscle depletion found was 33.8% by MMI and 61% by PTA (poor agreement, kappa = 0.25). Complication rates were 18.5% in gastrectomies and 50% in esophagectomies. No statistically significant difference was found between the presence of muscle depletion and complications. However, when stratified by surgery, a borderline association was found between the MMI and post esophagectomies complications (P = .05). CONCLUSION: Despite the high prevalence of muscle loss, it was not possible to correlate it with surgical outcomes for gastrectomies, but for esophagectomies, there may be relevance due to borderline association, although patients received nutritional therapy.

Disappearing colorectal liver metastases: Strategies for the management of patients achieving a radiographic complete response after systemic chemotherapy.

The mainstays of treatment for colorectal liver metastases (CRLMs) are surgery and chemotherapy. Chemotherapeutic benefits of tumor shrinkage and systemic control of micrometastases are in part counterbalanced by chemotoxicity that can modify the liver parenchyma, jeopardizing the detection of CRLM. This review addresses the clinical decision-making process in the context of radiographic and pathologic responses, the preoperative imaging workup, and the approaches to the liver for CRLM, which disappear after systemic chemotherapy.

Stereotactic Pelvic Navigation With Augmented Reality for Transanal Total Mesorectal Excision.

INTRODUCTION: Technical difficulty and unfamiliar surgical anatomy are the main challenges in transanal total mesorectal excision. Precise 3-dimensional real-time image guidance may facilitate the safety, accuracy, and efficiency of transanal total mesorectal excision. TECHNIQUE: A preoperative CT was obtained with 10 skin fiducials and further processed to emphasize the border of the anatomical structure by 3-dimensional modeling and pelvic organ segmentation. A forced sacral tilt by placing a 10-degree wedge under the patient's sacrum was induced to minimize pelvic organ movement caused by lithotomy position. An optical navigation system with cranial software was used. Preoperative CT images were loaded into the navigation system, and patient tracker was mounted onto the iliac bone. Once the patient-to-image paired point registration using skin fiducials was completed, the laparoscopic instrument mounted with instrument tracker was calibrated for instrument tracking. After validating the experimental setup and process of registration by navigating laparoscopic anterior resection, stereotactic navigation for transanal total mesorectal excision was performed in the low rectal neuroendocrine tumor. RESULTS: The fiducial registration error was 1.7 mm. The accuracy of target positioning was sufficient at less than 3 mm (1.8 ± 0.9 mm). Qualitative assessment using a Likert scale was well matched between the 2 observers. Of the 20 scores, 19 were judged as 4 (very good) or 5 (excellent). There was no statistical difference between mean Likert scales of the abdominal or transanal landmarks (4.4 ± 0.5 vs 4.3 ± 1.0, p = 0.965). CONCLUSIONS: Application of an existing navigation system to transanal total mesorectal excision for a low rectal tumor is feasible. The acceptable accuracy of target positioning justifies its clinical use. Further research is needed to prove the clinical need for the procedure and its impact on clinical outcomes.

Métodos de avaliação da circulação pulmonar / Diagnosthic methods of pulmonary circulation

No contexto desta revisão sobre hipertensão pulmonar o presente artigo aborda o papel dos diferentes exames utilizados para avaliação anatômica e funcional da circulação pulmonar, com realce para os baseados em imageamento com diversos métodos.

Diagnóstico por imagem no trauma abdominal / Imaging in abdominal trauma

A presente revisäo objetiva descrever os recentes avanços tecnológicos dos métodos de diagnóstico por imagem e sua atual aplicabilidade no manuseio dos pacientes com trauma abdominal, bem como as principais apresentações pelos métodos de imagem dos diversos órgäos envolvidos

O papel da radiologia na Unidade de Terapia Intensiva / The role of radiology in Intensive Care Units

O presente trabalho tem o intuito de abranger da forma mais ampla possível, os diferentes meios diagnósticos disponíveis atualmente para a avaliaçäo de pacientes em Unidade de Terapia Intensiva (UTI). Desta forma, alguns conceitos radiológicos essenciais para a interpretaçäo e correta solicitaçäo de exames seräo abordados com um enfoque prático e objetivo.