Utility of diffusion-weighted imaging in the diagnosis of inguinal lymph node metastasis with malignant melanoma

Malignant melanoma is a malignancy of pigmentproducing cells(melanocytes) located predominantly in the skin. Nodal metastases are an adverse prognostic factor compromising long term patient survival. Therefore, accurate detection of regional nodal metastases is required for optimization of treatment. Computed tomography(CT) and magnetic resonance imaging(MRI) remain the primary imaging modalities for regional staging of malignant melanoma. However, both modalities rely on size-related and morphological criteria to differentiate between benign and malignant lymph nodes, decreasing the sensitivity for detection of small metastases. Surgery is the primary mode of therapy for localized cutaneous melanoma. Patients should be followed up for metastases after surgical removal. We report here a case of inguinal lymph node enlargement with a genital vesicular lesion with a history of surgery for malignant melanoma on her thigh two years ago. CT and diffusion weighted-MRI(DW-MRI) were applied for the lymph node identification. DW-MRI revealed malignant lymph nodes due to malignant melanoma metastases correlation with pathological findings.

COVID-19-related cardiomyopathy:Can dual-energy computed tomography be a diagnostic tool?

BACKGROUND No study on dual energy computed tomography(DECT)has been found in the literature to evaluate possibly fatal cardiac/myocardial problems in corona virus disease 2019(COVID-19)patients.Myocardial perfusion deficits can be found in COVID-19 patients even without any significant coronary artery occlusion,and these deficits can be shown via DECT with a perfect interrater agreement.AIM To assess lung perfusion alterations in COVID-19 patients.To our knowledge,no study using DECT has been performed to evaluate possibly fatal cardiac/myocardial problems in COVID-19 patients.The purpose of this study is to evaluate the role of DECT in the detection of COVID-19-related cardiac diseases.METHODS Two blinded independent examiners evaluated CT images using the 17-segment model according to the American Heart Association’s classification of the segmentation of the left ventricular myocardium.Additionally,intraluminal diseases and abnormalities in the main coronary arteries and branches were investigated.Following segment-by-segment analysis,perfusion deficiencies identified on the iodine map pictures on DECT were identified.RESULTS The study enrolled a total of 87 patients.Forty-two of these individuals were classified as COVID-19 positive,and 45 were classified as controls.Perfusion deficits were identified in 66.6%(n=30)of the cases.All control patients had a normal iodine distribution map.Perfusion deficits were found on DECT iodine map images with subepicardial(n=12,40%),intramyocardial(n=8,26.6%),or transmural(n=10,33.3%)anatomical locations within the left ventricular wall.There was no subendocardial involvement in any of the patients.CONCLUSION Myocardial perfusion deficits can be found in COVID-19 patients even without any significant coronary artery occlusion.These deficits can be shown via DECT with a perfect interrater agreement.Additionally,the presence of perfusion deficit is positively correlated with D-dimer levels.