Single-center analysis of cardiac amyloidosis using 99m Tc-HMDP imaging for diagnosis and evaluation after tafamidis treatment.

This study aimed to evaluate the diagnostic performance of 99m Tc-hydroxymethylene diphosphonate ( 99m Tc-HMDP) imaging for cardiac amyloidosis and to demonstrate changes in cardiac uptake of 99m Tc-HMDP after tafamidis treatment. Seventy-five patients with suspected cardiac amyloidosis who underwent 99m Tc-HMDP imaging were included. We compared visual Perugini grades and semiquantitative heart-to-contralateral (H/CL) area ratios, myocardial maximum standardized uptake value (SUVmax), and peak of SUV (SUVpeak) between cardiac transthyretin amyloidosis (ATTR) and amyloid light-chain amyloidosis (AL). Comparison of interobserver reproducibility between H/CL ratios and myocardial SUVmax/SUVpeak was performed. H/CL ratio of 99m Tc-HMDP and myocardial SUVmax/SUVpeak were compared before and after tafamidis administration for cardiac wild-type ATTR. Among 75 patients, 20 patients (26.7%) were visually positive based on Perugini grade. Fifteen and three patients were pathologically identified as cardiac ATTR and AL, respectively. ATTR group ( n  = 15) had significantly higher H/CL ratios of 99m Tc-HMDP than AL group ( n  = 3) ( P  = 0.003). ATTR group ( n  = 15) had significantly higher myocardial SUVmax/SUVpeak of 99m Tc-HMDP than AL group ( n  = 2) ( P  = 0.015). Myocardial SUVmax/SUVpeak had better interobserver reproducibility than H/CL ratios. After tafamidis treatment for cardiac wild-type ATTR, the decrease in myocardial SUVpeak was significant but not in H/CL ratios and myocardial SUVmax. H/CL ratio and SUVmax/SUVpeak in 99m Tc-HMDP imaging were useful for diagnosing cardiac ATTR. Myocardial SUVpeak may be useful for monitoring changes in cardiac uptake after tafamidis treatment for cardiac ATTR.

被引量：- 发表：1970

SeHCAT retention measurements may be compromised by traces of 177Lu/177mLu more than 90 days after 177Lu-DOTATATE was administered.

被引量：- 发表：1970

Visual assessments of 11C-Pittsburgh compound-B PET vs. 18F-flutemetamol PET across the age spectrum.

被引量：- 发表：1970

Automatic detection and segmentation of lesions in 18 F-FDG PET/CT imaging of patients with Hodgkin lymphoma using 3D dense U-Net.

The accuracy of automatic tumor segmentation in PET/computed tomography (PET/CT) images is crucial for the effective treatment and monitoring of Hodgkin lymphoma. This study aims to address the challenges faced by certain segmentation algorithms in accurately differentiating lymphoma from normal organ uptakes due to PET image resolution and tumor heterogeneity. Variants of the encoder-decoder architectures are state-of-the-art models for image segmentation. Among these kinds of architectures, U-Net is one of the most famous and predominant for medical image segmentation. In this study, we propose a fully automatic approach for Hodgkin lymphoma segmentation that combines U-Net and DenseNet architectures to reduce network loss for very small lesions, which is trained using the Tversky loss function. The hypothesis is that the fusion of these two deep learning models can improve the accuracy and robustness of Hodgkin lymphoma segmentation. A dataset with 141 samples was used to train our proposed network. Also, to test and evaluate the proposed network, we allocated two separate datasets of 20 samples. We achieved 0.759 as the mean Dice similarity coefficient with a median value of 0.767, and interquartile range (0.647-0.837). A good agreement was observed between the ground truth of test images against the predicted volume with precision and recall scores of 0.798 and 0.763, respectively. This study demonstrates that the integration of U-Net and DenseNet architectures, along with the Tversky loss function, can significantly enhance the accuracy of Hodgkin lymphoma segmentation in PET/CT images compared to similar studies.

被引量：- 发表：1970

18 F FDG PET/CT versus 99m Tc MDP Bone scintigraphy in imaging of metastatic osseous disease in breast cancer patients; Solving the discrepancies in light of serum markers.

To assess the performance of 18 F-fluorodeoxyglucose (FDG) PET/computed tomography (CT) versus 99m Tc MDP bone scan in assessment of metastatic osseous disease in breast cancer patients in relation to serum markers. We reviewed PET/CT studies and bone scans for 37 patients (mean age of 55.38 ± 13.08 years) with metastatic breast cancer to bone. To assess metastatic osseous burden, we used semiquantitative scores derived from PET/CT (PMS) and bone scans (BMS). We used McNemar test to compare lesion detection between both modalities and receiver operator characteristic analysis to define the cutoff value of serum CA 15-3 that best predicts additional value for PET/CT over bone scan. In 13 patients (35.1%), more lesions or higher-intensity lesions were detected on PET/CT, while only 4 patients (10.8%) had more prominent lesions on bone scans ( P = 0.049). Additional lesions seen on PET/CT are predominantly osteolytic or medullary (early phase). Most lesions with higher uptake on bone scans appear sclerotic (late phase). CA 15-3 was positively correlated to PMS ( r = 0.386; P = 0.018) but not to BMS ( r = -0.027; P = 0.874). However, serum alkaline phosphatase was positively correlated to both PMS ( r = 0.389; P = 0.017) and BMS ( r = 0.363; P = 0.027). CA 15-3 value of >47 U/ml best predicted additional findings on PET/CT compared to bone scans (area under the curve = 0.708; P = 0.0261). FDG PET/CT detects metastatic osseous lesions during an earlier phase. A higher CA 15-3 predicts a higher metastatic burden on PET/CT but not on bone scan. Bone scans are less specific, likely by missing early lesions and detecting persistent uptake in healing sclerotic lesions.

被引量：- 发表：1970