Recent Patents on Medical Imaging (Discontinued) - Volume 4, Issue 2, 2014

This paper reviewed three state-of-the-art image fusion methods that were developed based on the estimation theory and evaluated these methods in the fusion of PET/CT images for radiotherapy applications. These fusion methods were developed in a framework of maximum likelihood estimate and firstly introduced the expectation-maximization algorithm to image fusion at either pixel-level or feature-level. Some recent patents on similar image fusion approaches have been discussed. The estimation theory based methods were previously evaluated for the fusion of visual and infrared images, however, they have not been tested for fusion of medical images such as PET/CT images. In this study we demonstrated through experiments the potential applicability of the pixel-level fusion and region-level fusion approaches based on the EM algorithm for PET and CT image fusions. We have shown that the fused image might be useful for tumor target delineation and image-guided radiotherapy.

Objective: We present a full description of our virtual mammography simulator, which was already introduced in a previous short version. Herewith we give many details omitted there. Materials: We work with a professional mammographer and a transparent breast phantom. The phantom contains artificial nodules, and their displacement under compression can be easily tracked through a transparency sheet with a printed millimetre scale. Compared with many other works in the literature, for instance, our approach is the first one that includes a transparent breast phantom. Moreover, we utilize the Surface Evolver, which is a general-purpose simulator of physical experiments with applications in many areas of knowledge. Our model allows to add and to work with different internal parts of the breast simultaneously, and the patent is a tool that helps identify such parts. Methods: With the Surface Evolver we have implemented a program that simulates the main steps of taking mammographies. These steps are reproduced in a totally virtual environment. With the mammographer, and the transparency millimeter sheet fixed on its upper plate, we performed compressions on the phantom and recorded them in videos. The videos show the displacements of the nodules from different viewpoints. We are still equating these trajectories in order to implement them in our model. Results: We have obtained a virtual mammography simulator of which the source code is fully available. It reproduces all the main steps of taking a real mammography. However, nodule trajectories will only be implemented in a forthcoming work. Herewith we use the term nodule but our simulator will also track microcalcifications, which count on specific Computer Aided Detection/Diagnosis (CAD) like the patent. They are much smaller than nodules, which also have devoted CAD-systems like the patents. Conclusion: We conclude that the Surface Evolver makes our programs relatively short, easy to handle and to understand. We have not worked with any patients in our experiments but a professional gynaecologist checked, tested and approved the virtual mammographer. All body data used in our work refer to a hypothetical volunteer.

This study aimed to evaluate the effect of intravenous (IV) contrast media on semi quantification value during fluorine-18 fluorodeoxyglucose (18F-FDG) PET/CT in cancer imaging. We reviewed whole body 18F-FDG PET/CT scans of 51 oncology cases performed with and without IV contrast administration. Non contrast-enhanced CT (NECT) images were acquired following IV injection of FDG then followed by contrast-enhanced CT (CECT) images acquisition utilizing non-ionizing iodinated contrast media without positional change. The contrast injection was acquired using an automatic intravascular injection conversion kit (U.S. Patent No. 5,792,102, 1998). PET images were reconstructed using both NECT and CECT image datasets. Region of interest (ROI) was drawn on field of view over the heart, liver, spleen, inferior vena cava, psoas major muscle, urinary bladder and site of lesion on PET/CECT images. Similar ROI was copied to the corresponding PET/NECT images. The maximum standardized uptake values (SUVmax) of both datasets were compared using paired sample t-test with p < 0.05 considered as significant. The mean ± standard deviation percentage differences of SUVmax between PET/CECT and PET/NECT for all investigated organs and lesions were not statistically significant (p > 0.05). Contrast-enhanced 18F-FDG PET/CT protocol did not cause significant effect in PET semiquantification uptake value, hence this protocol can be recommended in routine PET/CT examination, optimizing its role as a ‘one-stop’ imaging modality.

Spectral imaging technology is an emerging modality that combines the advantages of both imaging and spectroscopy (high spatial and spectral resolution) in one device. The technology has potential in numerous medical imaging and diagnostic applications. In this review, we describe the techniques used to acquire spectral images and the methods used for analyzing spectral images. We then provide detailed review about the progress of the spectral imaging technology in skin and endoscopy applications. This review also covers the recent patents on spectral imaging devices, methods, and data analysis algorithms.

Myocardial infarction (MI) and heart failure (HF) are leading causes of mortality and morbidity in the Western World. Therapeutic approaches using interventional cardiology and bioengineering techniques have thus far focused on either salvaging viable tissue post-infarction or preserving cardiac function in the failing myocardium. Regenerative medicine on the other hand, attempts to renew damaged tissue and enhance cardiac functional performance. Tremendous advances have been made in this field since the introduction and ethical approval for use of stem-cells (SC) and relevant technologies in pre-clinical and clinical practice. While study outcomes are still ambivalent on the potential translational impact of SCs, renewed hope has arisen since the introduction of induced pluripotent stem-cells (iPS) and the prospect of intact organ development and transplantation. The aim of this work is to review recent discoveries and the patent landscape employing stem-cell engineering, labeling and image-based monitoring strategies, their use in bioreactors and constructions of enriched bio-artificial membranes, as well as the potential role in artificial organ development and transplantation, with relevance to anticipated impact in pre-clinical screening and widespread clinical use.