18 F-FDG PET/MRI of Primary Hepatic Malignancies: Differential Diagnosis and Histologic Grading

BACKGROUND: Distinguishing between IHCC and HCC is important because of their differences in treatment and prognosis. The hybrid Positron Emission Tomography/magnetic Resonance Imaging (PET/MRI) system has become more widely accessible, with oncological imaging becoming one of its most promising applications. OBJECTIVE: The objective of this study was to see how well 18F-fluorodeoxyglucose (18F-FDG) PET/MRI could be used for differential diagnosis and histologic grading of primary hepatic malignancies. METHODS: We retrospectively evaluated 64 patients (53 patients with HCC, 11 patients with IHCC) with histologically proven primary hepatic malignancies using 18F-FDG/MRI. The Apparent Diffusion Coefficient (ADC), Coefficient of Variance (CV) of the ADC, and standardized uptake value (SUV) were calculated. RESULTS: The mean SUVmax value was higher for IHCC (7.7 ± 3.4) than for HCC (5.2 ± 3.1) (p = 0.019). The area under the curve (AUC) was 0.737, an optimal 6.98 cut-off value providing 72% sensitivity and 79% specificity. The ADCcv value in IHCC was statistically significantly higher than in HCC (p=0.014). ADC mean values in HCCs were significantly higher in low-grade tumors than in high-grade tumors. The AUC value was 0.73, and the optimal cut-off point was 1.20x10-6 mm2/s, giving 62% sensitivity and 72% specificity. The SUVmax value was also found to be statistically significantly higher in the high-grade group. The ADCcv value in the HCC low-grade group was found to be lower than in the highgrade group (p=0.036). CONCLUSION: 18F FDG PET/MRI is a novel imaging technique that can aid in the differentiation of primary hepatic neoplasms as well as tumor-grade estimation.

HOW USEFUL IS ELASTOGRAPHY IN THE FOLLOW-UP OF ACHILLES TENDON REPAIR?

Introduction: In addition to conservative modalities in the treatment of Achilles tendon injuries, open, percutaneous and minimally invasive semi-open techniques, as well as biological open surgical repair methods are used as surgical options. Compression elastography is one of the methods used for the follow-up of treatment in Achilles tendon injuries. Methods: 23 patients were included in our study between July 2013 and June 2014, as long as they had at least 4 years of follow-up. In the final control, the intact side and the operated side were both examined and compared. The variables were the American Orthopedic Foot and Ankle Score (AOFAS) which is measured as a functional score considering plantar flexion and dorsiflexion; calf circumference; Achilles tendon anteroposterior (AP) diameter; and elastographic examination. Results: The strain ratio value and AP diameter of the patients was significantly higher on the operated side than on the non-operated side (p <0.001). There was no significant difference between the plantar flexion and dorsiflexion degrees on the operated side of the patients(p> 0.05). No correlation was observed between strain ratio and AOFAS (p: 0,995). Conclusion: Elastography is not a useful technique to evaluate functional results on long-term tendon healing. Level of Evidence III; Retrospective comparative study.

Introdução: Além de métodos mais conservadores de terapia, utilizam-se, como opções cirúrgicas para o tratamento das lesões do tendão do calcâneo, técnicas abertas, percutâneas e semiabertas minimamente invasivas, bem como métodos cirúrgicos de reparo aberto. A elastografia por compressão é um dos métodos utilizados para o acompanhamento do tratamento das lesões do tendão do calcâneo. Métodos: Entre julho de 2013 e junho de 2014, 23 pacientes com pelo menos 4 anos de seguimento foram incluídos em nosso estudo. No controle final, o lado intacto e o lado operado foram examinados e comparados. As variáveis foram o American Orthopaedic Foot and Ankle Score, que foi medido como pontuação funcional por meio da flexão plantar e dorsiflexão; a circunferência da panturrilha; o diâmetro anteroposterior (AP) do tendão do calcâneo; e exame elastográfico. Resultados: O índice de tensão e o diâmetro AP dos pacientes foram significativamente maiores no lado operado do paciente que no lado não operado. Não houve diferença significativa entre os graus de flexão plantar e dorsiflexão dos pacientes no lado operado (p> 0,05). Não foi observada correlação entre strain ratio e AOFAS(p: 0,995). Conclusão: Acreditamos que a elastografia não seja uma técnica útil para avaliar os resultados funcionais na cicatrização do tendão em longo prazo. Nível de evidência III; Estudo comparativo retrospectivo.

Prediction of Prostate Cancer Aggressiveness Using a Novel Multiparametric Magnetic Resonance Imaging Parameter: Tumor Heterogeneity Index.

BACKGROUND AND AIMS: The aim of this study was to evaluate if the tumor heterogeneity index can predict the aggressiveness of prostate cancer (PCa) in patients diagnosed by magnetic resonance imaging (MRI) fusion biopsy. MATERIAL AND METHODS: Patients who underwent MRI fusion prostatic biopsy between July 2019 and December 2020 were retrospectively reviewed. Tumor heterogeneity index (coefficient of variation [CV]) and PI-RADS v2.1 scoring were analyzed by using multiparametric MRI. The patients were divided into 3 groups according to the risk classification, and the correlation between tumor heterogeneity index and PCa aggressiveness was studied by using apparent diffusion coefficient (ADCmean and ADCcv), Gleason score (GS), and risk classifications. RESULTS: One hundred two patients were included in this study. Patients were evaluated as low-risk (group 1) (n = 35), moderate-risk (group 2) (n = 37), and high-risk (group 3) (n = 30). ADCmean values for all groups were significantly different (p < 0.0001). ADCcv tumor heterogeneity index values were higher in group 2 and group 3 by the score increases in subgroups according to GS, while being higher than group 1 (p < 0.001). The multivariate analysis revealed that prostate-specific antigen, PI-RADS, ADCmean, and ADCcv values were predictive for tumor aggressiveness. CONCLUSION: ADCcv value as a tissue texture parameter can be used as a new biomarker to evaluate tumor aggressiveness in patients with PCa.

Symptomatic COVID-19 Reinfection with Pericardial and Pleural Involvement.

Coronavirus disease 2019 (COVID-19) is a contagious acute respiratory tract infection caused by Severe Acute Respiratory Syndrome CoronaVirus-2 (SARS-CoV-2), a beta coronavirus first discovered in Wuhan, China in late 2019. COVID-19 is spreading rapidly globally and has been officially declared a pandemic by the World Health Organization (WHO) as of March 2020. Most recent studies suggest that immunity can develop after an episode of severe acute respiratory syndrome Infections. There are few cases with severe symptomatic reinfection. Here we present the case of a healthy 46-year-old man with pericardial-pleural and lung involvement in the setting of COVID-19 infection first, and severe symptomatic reinfection thereafter.

How useful is elastography in the follow-up of achilles tendon repair? / Quão útil é a elastografia no acompanhamento do reparo do tendão do calcâneo?

ABSTRACT Introduction: In addition to conservative modalities in the treatment of Achilles tendon injuries, open, percutaneous and minimally invasive semi-open techniques, as well as biological open surgical repair methods are used as surgical options. Compression elastography is one of the methods used for the follow-up of treatment in Achilles tendon injuries. Methods: 23 patients were included in our study between July 2013 and June 2014, as long as they had at least 4 years of follow-up. In the final control, the intact side and the operated side were both examined and compared. The variables were the American Orthopedic Foot and Ankle Score (AOFAS) which is measured as a functional score considering plantar flexion and dorsiflexion; calf circumference; Achilles tendon anteroposterior (AP) diameter; and elastographic examination. Results: The strain ratio value and AP diameter of the patients was significantly higher on the operated side than on the non-operated side (p <0.001). There was no significant difference between the plantar flexion and dorsiflexion degrees on the operated side of the patients(p> 0.05). No correlation was observed between strain ratio and AOFAS (p: 0,995). Conclusion: Elastography is not a useful technique to evaluate functional results on long-term tendon healing. Level of Evidence III; Retrospective comparative study.

RESUMO Introdução: Além de métodos mais conservadores de terapia, utilizam-se, como opções cirúrgicas para o tratamento das lesões do tendão do calcâneo, técnicas abertas, percutâneas e semiabertas minimamente invasivas, bem como métodos cirúrgicos de reparo aberto. A elastografia por compressão é um dos métodos utilizados para o acompanhamento do tratamento das lesões do tendão do calcâneo. Métodos: Entre julho de 2013 e junho de 2014, 23 pacientes com pelo menos 4 anos de seguimento foram incluídos em nosso estudo. No controle final, o lado intacto e o lado operado foram examinados e comparados. As variáveis foram o American Orthopaedic Foot and Ankle Score, que foi medido como pontuação funcional por meio da flexão plantar e dorsiflexão; a circunferência da panturrilha; o diâmetro anteroposterior (AP) do tendão do calcâneo; e exame elastográfico. Resultados: O índice de tensão e o diâmetro AP dos pacientes foram significativamente maiores no lado operado do paciente que no lado não operado. Não houve diferença significativa entre os graus de flexão plantar e dorsiflexão dos pacientes no lado operado (p> 0,05). Não foi observada correlação entre strain ratio e AOFAS(p: 0,995). Conclusão: Acreditamos que a elastografia não seja uma técnica útil para avaliar os resultados funcionais na cicatrização do tendão em longo prazo. Nível de evidência III; Estudo comparativo retrospectivo.

Value of Intravoxel Incoherent Motion for Hepatocellular Carcinoma Grading.

BACKGROUND: To evaluate the diagnostic accuracy of intravoxel incoherent motion (IVIM) parameters in estimation of hepatocellular carcinoma (HCC) grading. MATERIALS AND METHODS: Twenty-nine patients with histopathologically diagnosed as 42 HCC at explant were included in this retrospective study. All patients were examined by 1.5T magnetic resonance imaging with the use of 4-channel phased array body coil. In addition to routine pre- and postcontrast sequences, IVIM (16 different b factors varying from 0 to 1300 s/mm2) and conventional diffusion-weighted imaging (3 different b factors of 50, 400, 800 s/mm2) were obtained with single-shot echo planar spin echo sequence. Apparent diffusion coefficient (ADC) and IVIM parameters including mean D (true diffusion coefficient), D* (pseudo-diffusion coefficient associated with blood flow), and f (perfusion fraction) values were calculated. Histopathologically, HCC was classified as low (grade 1, 2) and high (grade 3, 4) grade in accordance with the Edmondson-Steiner score. Quantitatively, ADC, D, D*, and f values were compared between the low- and high-grade groups by Student t test. The relationship between the parameters and histologic grade was analyzed using the Spearman's correlation test. To evaluate the diagnostic performance of the parameters, receiver operating characteristic analysis was performed. RESULTS: High-grade HCCs had significantly lower ADC and D values than low grade groups (P = .005 and P = .026, retrospectively); ADC and D values were inversely correlated with tumor grade (r = -0.519, P = .011, r = -0.510, P = .026, respectively). High-grade HCCs had significantly higher f values when compared with the low-grade group (P = .005). The f values were positively correlated with tumor grade (r = 0.548, P = .007). The best discriminative parameter was f value. Cut-off value of 32% of f values showed sensitivity of 75.6% and a specificity of 73.5%. CONCLUSION: ADC values and IVIM parameters such as f values appear to reflect the grade of HCCs.

The prevalence and characteristics of the subclavius posticus muscle in the adult population on MRI.

PURPOSE: The subclavius posticus muscle (SPM) is an aberrant muscle, and the presence of the SPM has a clinical significance, since the SPM might lead to thoracic outlet syndrome (TOS). To date, no radiological study has been evaluated the prevalence of the SPM in the adult population. In this study, we aimed to assess the prevalence of the SPM using magnetic resonance imaging (MRI). METHODS: We retrospectively reviewed brachial plexus, neck, and thoracic MRI of the patients who underwent MRI for various pathologies. Only the patients whose MRI examinations did not have sufficient image quality and the patients who had any pathology that directly involved the thoracic outlet region were excluded from the study. The observers assessed images in the coronal plane to detect the presence of the SPM. The thickness of the muscle and the distance between the SPM and brachial plexus were also noted. RESULTS: MRI examinations of 350 patients, 174 males and 176 females, were evaluated. SPM was detected in 29 patients (8.3%). In 6 patients (1.7%), we identified bilateral SPM. The mean thickness of the muscle was 6.10 ± 1.60 mm (range 2.5-10 mm). In 21 sides (60%), the brachial plexus and SPM were touching each other. In the remaining 14 sides (40%), the mean distances between the SPM and brachial plexus were 2.32 ± 0.62 mm (range from 1.7 to 3.6 mm). CONCLUSIONS: We conducted the first radiological study that evaluated the prevalence of the SPM, and we also assessed the thickness of the SPM and the distance between the SPM and brachial plexus. We highlight that our study might be accounted as a first step for future studies to assess the role of the SPM in TOS.

The correlation between biological activity and diffusion-weighted MR imaging and ADC value in cases with prostate cancer.

PURPOSE: Firstly, we aimed to investigate the correlation among dynamic contrasted magnetic resonance (MR) images, diffusion-weighted MR images, and apparent diffusion coefficent (ADC) values in patients with prostate cancer. Secondly, we aimed to investigate the roles of these variables on clinical risk classification and the biological behavior of the prostate cancer. METHODS: A total of sixty with prostatic adenocarcinoma patients diagnosed between January 2011 and May 2013 were retrospectively included in the study. Risk classification of patients were evaluated as low-risk (Group 1) (n = 20) (Stage T1c-T2a, PSA < 10 ng/ml, Gleason Score < 7), moderate-risk (Group 2) (n = 18) (Stage T1b-T2c, PSA = 10-20 ng/ml, Gleason Score = 7) and high-risk (Group 3) (n = 22) (Stage > T3a, PSA > 20 ng/ml, Gleason Score > 7). Diffusion-weighted MR images, dynamic contrasted MR images, and ADC values of the prostates were correlated. RESULTS: ADC values of the cases in Group 3 were lower than those of the other groups (p < 0.001). ADC values of the areas without malignancy did not differ significantly between groups (p > 0.05). Biological activity of the tumor tissue was determined by GS, while a negative correlation was observed between GSs and ADC values of the patients, (p < 0.001). CONCLUSION: In tumors with higher Gleason scores, lower ADC values were obtained. These measured values can play a role in the noninvasive determination of the cellularity of the tumoral mass.