Focal FDG Activity in the Region of Right Atrium: Coregistered CT Identifies Three Benign Etiologies

We present the whole body FDG PET-CT images on 3 different patients with benign focal activity in the region of the right atrium. Co-registered CT correctly identified the cause of focal FDG activity as: right atrial appendage, lipomatous hypertrophy of the interatrial septum, and catheter-related activity. Although all these have been reported separately in the literature, we are presenting them together to emphasize the importance of recognizing the benign causes of FDG uptake in the region of right atrium and the role of co-registered CT in improving the accuracy and specificity of the FDG PET

FDG PET Appearance of “Cannonball” Pulmonary Metastases

AbstractWe present the case of a 67-year-old woman with a recent tissue diagnosis of endometrial cancer whose FDG PET scan exhibited multiple hypermetabolic foci through out both the lungs. Contemporaneously acquired conventional radiolographs showed parenchymal nodules that demonstrated the classic “cannon ball” appearance of pulmonary metastases. Pulmonary metastasis from an endometrial primary is a rare event, as are the presence of pulmonary findings at the time of initial staging. Thus, this case demonstrates rare, and yet, distinctive aspects of the disease presentation and image correlation across the various imaging modalities

Protective Role of Decellularized Human Amniotic Membrane from Oxidative Stress-Induced Damage on Retinal Pigment Epithelial Cells

Oxidative stress is an important cause for several retinal aging diseases. Cell therapy using a decellularized human amniotic membrane (dHAM) as a tissue scaffold for retinal pigment epithelial cells has a potential therapeutic role under such pathological conditions. This is attributed by the anti-inflammatory, antimicrobial, low-immunogenicity aspects of dHAM, apart from harboring a drug reservoir potential. The underlying mechanisms for maintaining the physiological properties of transplanted cells and their survival in a diseased milieu using dHAM has remained unexplored/unanswered. Hence, we investigated the potential role of dHAM in preserving the cellular functions of retinal pigment epithelium in an oxidative stress environment. Adult human retinal pigment epithelial (ARPE-19) cells were cultured on dHAM or tissue culture dishes under hyperoxia. Gene expression, immunofluorescence staining, enzyme-linked immunosorbent assay (ELISA), and scanning electron microscopy (SEM) were performed to assess the levels of reactive oxygen species, proliferation, apoptosis, epithelial-mesenchymal transition, phagocytosis, and secretion of vascular endothelial factors. These results indicate reduced epithelial-mesenchymal transition, generation of reactive oxygen species (p <= 0.0001), and apoptosis (p <= 0.05) in cells cultured on dHAM, compared to those on tissue culture dishes under oxidative stress conditions. Concomitantly, the secretion of the vascular endothelial growth factor was significantly reduced (p <= 0.01) on dHAM. Phagocytic activity was significantly higher (p <= 0.001) in cells cultured on dHAM and were comparable to those cells cultured on tissue culture dishes. SEM images showed a clustered growth pattern on dHAM compared to an elongated morphology when cultured on tissue culture dishes under oxidative stress conditions. These findings demonstrate the utility of dHAM as a scaffold for growing retinal epithelial cells and to maintain their physiological properties in an oxidative stress condition with a potential to develop regenerative medicine strategies to treat degenerative eye diseases