No abstract

Staging and therapy monitoring of malignant lymphomas relies heavily on imaging using arbitrary size criteria from computed tomography (CT) and sometimes non-specific radionuclide studies to assess the activity of the disease. Treatment decisions are based on early assessment of the response to therapy and the residual volume of the disease. Our initial experience is reported using a new noninvasive, inexpensive, and reproducible passive imaging modality, Dynamic Infrared Imaging (DIRI), which may add a new dimension to functional imaging. This system relies on its ability to filter the raw infrared signal using biological oscillatory behavior. It detects and analyzes minute oscillations of temperature and heat distribution in tumors. IntroductionThe treatment of malignant lymphomas depends heavily on imaging at the time of staging. With the progress in therapy there is an increasing demand for more frequent and accurate monitoring of the early response to treatment, as well as the detection of toxicity of chemotherapy. Early assessment of response and toxicity will allow more timely changes in the treatment of patients who are not responding, and may enhance the chances of decreasing toxic side effects and ultimately increase the prospect for a cure. Functional imaging techniques are becoming more widely accepted for this purpose, and imaging modalities using Ga-67 or FDG-PET show very promising results in this regard (1-5). Some studies suggest that very early restaging -as early as after one cycle of therapy -may be predictive of the treatment success or failure (1, 6). PET likewise, has been employed in the early monitoring of lymphoma patients on radio-immunotherapy (7). PET assessment of tumor glucose or amino acid metabolism with F-18 FDG, C-11 Thyrosin PET, C-11 cystein PET have shown very encouraging results in a variety of tumors, although larger studies are needed to confirm this concept (3, 7-9). Our report on this new imaging modality, Dynamic Infrared Imaging (DIRI) is based on our working hypothesis that tumors can be detectable as areas of long-wave (8-10µm) infrared photon flux that exhibit significantly different temporal behavior when compared to non-diseased tissue.In this study, we compare the ability of Dynamic Infrared Imaging (DIRI) to depict tumor masses in lymphoma patients for staging and therapy monitoring against CT, Ga-67 and FDG-PET.Staging CT, Ga-67 and FDG-PET were compared with DIRI images on ten patients (five males, five females) in age range from 25-50 years with newly

Near-infrared spectroscopy (NIRS) and laser Doppler flowmetry (LDF) have become the techniques of choice allowing the non-invasive study of local human skeletal muscle metabolism and blood perfusion on a small tissue volume (a few cm3). However, it has been shown that both NIRS and LDF measurements may show a large spatial variability depending on the position of the optodes over the investigated muscle. This variability may be due to local morphologic and/or metabolic characteristics of the muscle and makes the data interpretation and comparison difficult. In the present work, we use a third method to investigate this problem which permits fast, non-invasive mapping of the intramuscular vessel distribution in the human vastus latelralis muscle. This method uses an advanced, passive, infrared imaging sensor called a QWIP (quantum well infrared photodetector). We demonstrate, using a recovery-enhanced infrared imaging technique, that there is a significant presence of perforator vessels in the region of interest of approximately 30 x 18 cm (the number of vessels being: 14, 9, 8, 33, 17 and 18 for each subject, respectively). The presence of these vessels makes the skeletal muscle highly inhomogeneous, and may explain the observed NIRS and LDF spatial variability. We conclude that accurate comparison of the metabolic activity of two different muscle regions is not possible without reliable maps of vascular 'singularities' such as the perforator vessels, and that the QWIP-based imaging system is one method to obtain this information.

No abstract

No abstract