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Positron emission tomography (PET) is a nuclear medicine imaging technique that produces a three-dimensional functional image of the living body. This system detects pairs of gamma rays emitted indirectly by a positron-emitting radiotracer, which is introduced into the body as a biologically active tracer. Three-dimensional images of radiotracer concentration within the body are then constructed by computer graphic analysis. PET is both a medical and study tool used in clinical oncology (medical imaging and diagnosis of tumors and the search for metastases) and in preclinical animal studies, where it allows repeated scans of the same subject. PET is particularly valuable in cancer research because it increases the statistical quality of the data (research subjects can act as their own controls) and substantially reduces the number of animals needed for individual studies.

The Hotel industry of Pakistan is thriving for excellence in the arena of competitiveness. Management of hotels is striving hard to improve the service standard to satisfy the needs of customer and subsequently build and maintain long term relationship with them. This study endeavors to investigate the influence of the relationship orientation on “Reputation” and “Service standard” and the interrelation between “Reputation” and “Service standard”. Convenience sampling method was used. The data has been collected through survey questionnaires from 300 respondents. Statistical Package for the social sciences (SPSS) software was used to examine the hypothesized relationships in the research model. The findings revealed that the Relationship orientation and Mutual disclosure positively affect the hotel Reputation and Service standard, the hotel’s functional image perception; the hotel’s physical equipment, decor and environment; and the hotel’s response to customers, all are mutually related and emphasized in our variables that are significantly related to each other, therefore; they are useful for hotel management to achieve longterm growth in the hotel industry of Pakistan.

Background: Recurrences of glioma are usually local, suggesting the need for higher tumor dose. We investigated the boundaries for dose escalation of an 18F-fluoro-ethyl-tyrosine positron emission tomography defined target by intensity-modulated photon therapy (IMRT), volumetric modulated arc therapy (VMAT) and intensity-modulated proton therapy (IMPT). Materials and methods: Standard dose (60 Gy) and dose-escalated plans were calculated for seven patients using IMRT, VMAT and IMPT. The achieved boost dose, the dose to the organs at risk (OAR), the dose homogeneity (defined as overdose volume, ODV) and the ratio of the 30 Gy isodose curve and the boost volume (R30) were compared. The risk of radionecrosis was estimated using the ratio of the dose volume histograms of the brain (range 30–60 Gy). Results: The mean boost dose was 77.1 Gy for IMRT, 79.2 Gy for VMAT and 85.1 GyE for IMPT. Compared with the standard plan, the ODV was unchanged and the R30 increased (17%) for IMRT. For VMAT, the ODV decreased (7%) and the R30 was unchanged whereas IMPT substantially decreased ODV (61%), R30 (22%), OAR doses as well as the risk of radionecrosis. Conclusions: Dose escalation can be achieved with IMRT, VMAT and IMPT while respecting normal tissue constraints, yet with IMPT being most favorable.

—In functional brain imaging studies, especially when adjusting the functional image to define a standard brain, it is essential to describe the brain images obtained from different subjects using the same coordinate system. Across the years, studies have been conducted to develop a standard brain template that is compatible to different population although the human brain is highly different in shape and size between individuals and basic demographic factors. The Korean standard brain template was the early Eastern template developed and shows the difference between Eastern and Western brains. Compared to MNI and Talairach atlas, Korean brain template was shorter in anterior-posterior length. In Singapore, neonates’ brain template for multiple races was developed, where brain of the Indian neonates more elongated than Malay neonates. The latest study on 1,000 Chinese subjects has developed 10 new Chinese brain atlases comprising different ages and gender. Via these researches, it is proved that standard brain template could be different across age, culture and gender. In this review paper, the scenario of the standard brain templates development is briefly discussed, followed by the comparison of results obtained from previous study.

Objectives: Measuring Glomerular Filtration (GFR) using Gate’s method gives low radioactivity of approximately 74~111 MBq to a patient. Such low counts on image acquisition degrade image quality. The objective of this study was to limit the amount of radioactivity needed to acquire high-quality dynamic renal images when measuring GFR. Methods/Statistical Analysis: We performed experiments with different radio activities at matrix size of 128 x 128 or other matrix sizes to check overflow phenomenon of gammaray. Findings: Ideal total count was at radioactivity of approximately 37 MBq. However, measured total counts from acquire images showed certain counting loss. The average margin of error was –1.88 ± 1.61%. The mean value of GFR according to the radioactivity at more than 370 MBq was –2.91 ± 1.19 %. We could calculate GFR by substituting these results in GFR formula under the same condition. The mean GFR value was –1.89 ± 1.62% at radioactivity of 37 MBq and –2.93±1.2 % at radioactivity of more than 370 MBq. Conclusion: High-quality functional image could be acquired at the same time by increasing radioactivity to 370 MBq with higher matrix size. Improvements/Applications: With these results, we can improve diagnostic ability and make more accurate evaluation of renal function.

Brain surgery is generally guided by brain anatomical image, tumor removal maybe injure patients’ important tissues and functional areas, and result in death and permanent disability, these important tissue and functional areas are invisible in the anatomical image. This paper presents an image fusion software system, which can merge lesion, important tissues, brain functional image, brain atlas, fiber tract into anatomical image, and show them in 3D image. With the help of this system, surgeons can avoid important tissues and functional areas when they design surgical approach, they can also minimize intraoperative risk and postoperative deformity by the guidance of fusion image. Experiments show that the image fusion system is feasible and applicable to surgery.

One of the major advances in imaging in the last decade has been the combination of existing functional imaging techniques such as SPECT (single photon emission computed tomography) or positron emission tomography (PET) with x-ray computed tomography (CT), giving an anatomical framework to the functional image. PET/CT and SPECT/CT have changed the practice of nuclear medicine considerably since their introduction. This article examines how this hybrid technology evolved, its revolutionary impact, and that it is now seen as the first of potentially many multimodality hybrid imaging devices.

Corporate social responsibility (CSR) is regarded as a good strategic marketing tool and it has significant influence on consumers’ behaviours. The purpose of this study is to explore the indirect effects of different dimensions of CSR on brand loyalty in a real business context. This study focuses on legal and ethical responsibilities as two dimensions of social responsibility. The empirical results indicate that consumers’ perceived legal and ethical responsibilities of brands may improve brand loyalty through enhancing positive functional and symbolic images. Moreover, corporate legally responsible behaviour helps to enhance a more functional image perceived by consumers than a symbolic image, while ethically responsible action impacts a symbolic image more than a functional image. These results suggest firms should focus on key dimensions of social responsibility based on the expectations of consumers in their marketing programmes.

BACKGROUND AND PURPOSE: The planning process in radiotherapy (RT) typically involves the acquisition of a unique set of CT images - and eventually of functional images - which is used for delineation of target volumes (TV) and organs at risk (OAR) and for dose calculation. Restricting the delineation and dose calculation solely on pre-treatment images is an oversimplification as it is only a snapshot of the patient's anatomy. The objectives of the present study were (1) to assess the consequences of anatomic modification in dose distribution for both TVs and OARs; (2) to assess the potential benefit of adaptive strategies using Helical Tomotherapy (HT); and (3) to compare CT-based and FDG-PET-based adaptive planning strategies. MATERIALS AND METHODS: Ten patients with H&N SCC were imaged before and during concomitant chemo-RT using CT and FDG-PET acquisition after a mean dose of 14.2, 24.5, 35.0 and 44.9 Gy. Simultaneous integrated boost IMRT planning was performed using HT. We compared (1) the planned dose distribution, (2) the delivered dose distributions that took into account impact of anatomical modifications on dose distribution, (3) the adaptive dose distributions after replanning to take into account the anatomic modifications and the anatomic or functional GTV shrinkage. RESULTS: There was an increase between the planned and the delivered high dose volumes, which correlated with the slope of the GTV shrinkage. The adaptive high dose volumes were significantly smaller than the delivered ones. The difference between the adaptive and the delivered high dose volume also correlated with the slope of the GTV shrinkage. For both parotid glands combined, the delivered D(mean) showed a statistical trend for an increase of 4.4% compared to the planned D(mean). For the ipsilateral parotid glands, there was a correlation between the D(mean) gain and the slope of the GTV shrinkage when an adaptive planning was used. For the oral cavity, the adaptive D(mean) was 10% smaller than the delivered ones. For the PRV around the spinal cord, there was an increase of about 4.5% between the delivered and the planned D(2%). The adaptive planning translated into a decrease in D(2%) of 7.2%. The differences between the delivered and planned D(2%) and between the adaptive and the delivered D(2%) were correlated with the slope of the GTV shrinkage. For the CTV(proph) and PTV(proph) coverage, adaptive strategy induced a better dose conformation. No significant difference was observed in the various figures of merit between PET-based plan and CT-based isodose distributions. CONCLUSIONS: The dose distribution that is actually delivered to patients significantly differs from what was planned because of anatomic modifications. Adaptive multi-modality IMRT is feasible in H&N tumors and could compensate and improve dose distribution. Some useful surrogate criteria or "flags" are, however, needed to identify patients who might benefit from an adaptive strategy. The optimal adaptive strategy still needs to be defined and prospective studies will have to be conducted to address the safety and the clinical impact of such approaches on patient outcome.

In the context of a multidisciplinary approach for the diagnosis and treatment of ovarian cancer, the contribution of radiology includes the following four fundamental points: identification of the lesion, its characterization, study of its extension and evaluation of its evolution. This article describes the findings and key diagnostic elements in MDCT (Multidetector Computed Tomography) and MR (Magnetic Resonance), the contribution and indication of other technologies like PET (Positron Emission Tomography), and outlines the emergent techniques based on functional image analysis (dynamic contrast-enhanced MRI studies and MRI diffusion studies).

Measuring exercise-induced muscle activity is essential in sports medicine. Previous studies proposed measuring transverse relaxation time (T(2)) using muscle functional magnetic resonance imaging (mfMRI) to map muscle activity. However, mfMRI uses a spin-echo (SE) sequence that requires several minutes for acquisition. We evaluated the feasibility of T(2) mapping of muscle activity using ultrafast imaging, called fast-acquired mfMRI (fast-mfMRI), to reduce image acquisition time. The current method uses 2 pulse sequences, spin-echo echo-planar imaging (SE-EPI) and true fast imaging with steady precession (TrueFISP). SE-EPI images are used to calculate T(2), and TrueFISP images are used to obtain morphological information. The functional image is produced by subtracting the image of muscle activity obtained using T(2) at rest from that produced after exercise. Final fast-mfMRI images are produced by fusing the functional images with the morphologic images. Ten subjects repeated ankle plantar flexion 200 times. In the fused images, the areas of activated muscle in the fast-mfMRI and SE-EPI images were identical. The geometric location of the fast-mfMRI did not differ between the morphologic and functional images. Morphological and functional information from fast-mfMRI can be applied to the human trunk, which requires limited scan duration. The difference obtained by subtracting T(2) at rest from T(2) after exercise can be used as a functional image of muscle activity.

This study examines the relationship between the concern about well-being lifestyle and the perceived image of Hanji fiber. A survey was conducted among male and female consumers aged 20 and over in Jeonju and Daejon from January 4th to 11th, 2008. A total of 168 responses were analyzed by using descriptive statistics, factor analysis, and ANOVA via the SPSS ver. 12. As a result, four factors were determined in the concern for a well-being lifestyle; product consumption, enjoying culture, using therapy and managing the household. The perceived image of Hanji fiber were classified into four elements; traditional, high-quality, functional and popular images. Among the factors of the concern for a well-being lifestyle and the perceived image of Hanji fibers, a partial relationship was observed. There is a positive relationship, especially between the product consumption factor of a well-being lifestyle and the high-quality and functional image of Hanji fiber. Also, there was a positive relationship between the factor of managing the household and the traditional image of Hanji fiber. However, the therapy interest factor of a well-being lifestyle was negatively related to the traditional image of Hanji fiber.

Bone scintigraphy has been used as a helpful method in diagnosing lameness in small animals. It is a sensitive, non-invasive method to evaluate bone lesions and orthopaedic disorders. It provides a functional image of the skeleton and thereby aiding in the localisation and diagnosing of obscure lameness. Compared to human medicine one important difference is the inability of an animal to characterize its pain to the examiner. Another difference is the lacking cooperation of an animal during bone scintigraphy. Before this background are shown on the basis of 5 examples the advantages, the method and the different indication of bone scintigraphy. The technique of this method arrives from a human medicine protocol of a 2-phase-bone-scintigraphy and has to be done under light anaesthesia, to avoid artefacts of movement during acquisitions. The authors are convinced that bone scintigraphy is a very useful and diagnostic method for evaluation of obscure lameness because it can give a quick diagnosis and aimed therapy. Therefore secondary changes and additional costs can be avoided for the animal and its owner.

AIM: To evaluate the effect of the spasmolytic agent hyoscine butylbromide (HBB) on the quality of anatomical and functional imaging of the prostate. MATERIALS AND METHODS: One hundred and seventy-three patients were included in this retrospective study. Eighty-seven patients received intravenous HBB prior to scanning (HBB group) and 86 patients did not (non-HBB group). Multiparametric (mp) 3 T magnetic resonance imaging (MRI) was performed using a 32-channel body coil. Two radiologists independently evaluated the image quality of T2-weighted imaging (WI), diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) maps, using a five-point Likert scale. DWI was further assessed for distortion and artefact (four-point Likert scale), and T2WI for the presence of motion artefact or blurring. Dynamic contrast-enhanced (DCE) image quality was assessed by recording the number of corrupt contrast curve data points. RESULTS: T2W image quality in the HBB group was significantly higher than in the non-HBB group (3.63±1.11 versus 2.84±0.899); p

Voxel-based prescriptions of deliberately non-uniform dose distributions based on molecular imaging, so-called dose painting or theragnostic radiation therapy, require specification of a transformation that maps the image data intensities to prescribed doses. However, the functional form of this transformation is currently unknown. An investigation into the sensitivity of optimized dose distributions resulting from several possible prescription functions was conducted. Transformations between the radiotracer activity concentrations from Cu-ATSM PET images, as a surrogate of tumour hypoxia, and dose prescriptions were implemented to yield weighted distributions of prescribed dose boosts in high uptake regions. Dose escalation was constrained to reflect clinically realistic whole tumour doses and constant normal tissue doses. Optimized heterogeneous dose distributions were found by minimizing a voxel-by-voxel quadratic objective function in which all tumour voxels were given equal weight. Prescriptions based on a polynomial mapping function were found to be least constraining on their optimized plans, while prescriptions based on a sigmoid mapping function were the most demanding to deliver. A prescription formalism that fixed integral dose was less sensitive to errors in the choice of the mapping function than one that boosted integral dose. Integral doses to normal tissue and critical structures were insensitive to the shape of the prescription function. Planned target dose conformity improved with smaller beamlet dimensions until the inherent spatial resolution of the functional image was matched. Clinical implementation of dose painting depends on advances in absolute quantification of functional images and improvements in delivery techniques over smaller spatial scales.

Preoperative fMRI is one of the best established clinical fMRI applications. Due to the difficulties in recording and coregistration of functional image data, we present methods to standardize and automate these procedures. We used a self-made interactive software package (AFI — Automated Functional Imaging) to automate the time consuming and complex analysis of fMRI data. AFI controls the BrainVoyager program, a postprocessing software package, and furthermore facilitates data management, anonymization of patient data, storage, documentation, data export to neuronavigation systems and the opportunity of spatial transformation of image data for use in group studies. By the end of 2006 we have used this method on 123 patients with brain tumors and 47 patients with trigeminal neuralgia. The fundamental basis of multimodal neuronavigation is precise coregistration. EPI images contain spatial distortions of 5–15 mm. We were able to reduce the misregistration of EPI and FLASH images in a selectable region of interest to 1–2 mm. Furthermore AFI reduces the average evaluation time for a standard clinical fMRI study (four functional measurements, one anatomical data set) by approx. 50% from 140 minutes to about 70 minutes in comparison to manual evaluation by an expert. More importantly, the personal attendance time required for the evaluation decreases by 84% to 23 minutes as the remainder of the program runs automatically. In comparison to currently available online postprocessing software tools which are more limited in use, BrainVoyager can be used for coregistration, data export to neuronavigation systems and spatial transformation.

The purpose of this study was to conduct fast-acquired muscle functional magnetic resonance imaging (fast-mfMRI). Fast-mfMRI is a method of fusing fast MR images in order to visualize muscle activity. Exercise selectively increases the signal intensities (SI) of active muscles in T2-weighted magnetic resonance (MR) images. A fast-mfMRI image is a fusion of two types of images: an anatomic image acquired by the TrueFISP method and a functional image acquired by the SE-EPI (spin-echo echo-planar-imaging) method. MR images of four healthy males were recorded at rest before and after plantar flexion. The Gain of the MR signal remained constant from before the flexion exercise (at rest) to after the exercise. The data on the area of muscle activity could be extracted by adapting a threshold value obtained by a functional image at rest to the functional image after the exercise. By uniting the data on the area of muscle activity with the anatomic images after the exercise, we constructed a fused image rich in anatomical information and effective in visualizing muscle activity. These fast-mfMRI images can be acquired in 14 seconds. Our results suggest that fast-mfMRI has the potential to measure muscle activity in the trunk, where conventional mfMRI has been ineffective.

To investigate the hypothesis that CT ventilation functional image-based IMRT plans designed to avoid irradiating highly-functional lung regions are comparable to single-photon emission CT (SPECT) ventilation functional image-based plans.Three IMRT plans were created for eight thoracic cancer patients using: (1) CT ventilation functional images, (2) SPECT ventilation functional images, and (3) anatomic images (no functional images). CT ventilation images were created by deformable image registration of 4D-CT image data sets and quantitative analysis. The resulting plans were analyzed for the relationship between the deviations of CT-functional plan metrics from anatomic plan metrics (ΔCT-anatomic) and those of SPECT-functional plans (ΔSPECT-anatomic), and moreover for agreements of various metrics between the CT-functional and SPECT-functional plans.The relationship between ΔCT-anatomic and ΔSPECT-anatomic was strong (e.g., R=0.94; linear regression slope 0.71). The average differences and 95% limits of agreement between the CT-functional and SPECT-functional plan metrics (except for monitor units) for various structures were mostly less than 1% and 2%, respectively.This study demonstrated a reasonable agreement between the CT ventilation functional image-based IMRT plans and SPECT-functional plans, suggesting the potential for CT ventilation imaging to serve as a surrogate for SPECT ventilation in functional image-guided radiotherapy.

A medicina nuclear utiliza substâncias radioativas para diagnosticar e tratar doenças. Essa especialidade médica, capaz de fornecer informações fisiológicas e metabólicas sobre o corpo humano, se tornou uma ferramenta fundamental para a detecção precoce de muitas desordens, inclusive vários tipos de câncer. O presente artigo descreve os marcos históricos da medicina nuclear, os princípios físicos básicos que subjazem à tomografia por emissão de pósitrons (PET), um método de imagem usado para mapear a distribuição de radiofármacos no corpo para fins diagnósticos e terapêuticos, e o estado atual dessa modalidade no Brasil.In nuclear medicine, radioactive substances are used to diagnose and treat disease. This medical specialty, that can provide information about the human body's physiologic and metabolic processes, has become a key diagnostic tool for the early detection of many different disorders, including various types of cancer. The present article describes the historical milestones in nuclear medicine; the basic physical principles underlying positron emission tomography (PET), which is an imaging method used to map the distribution of radiopharmaceuticals in the body for diagnostic and therapeutic purposes, and the current status of this modality in Brazil.

Radiopharmaceuticals are major determinants of progress in Nuclear Medicine. Besides 18 FDG, the most common PET tracer, several other molecules are under evaluation, such as 18 F-fluoride for bone studies, numerous ligands for neurotransmission, 18 F-DOPA for neuro-endocrine tumors or generator produced 68 Ga-peptides for various cancers. Nuclear medicine gradually changes for “molecular imaging” and medical imaging, which was at the beginning mainly anatomic, has progressed in the direction of functional and metabolic imaging. The present challenge is to achieve some degree of “in vivo” biochemistry or even histology or genetics. The importance of anatomic/functional image fusion justifies the development of combined PET-CT instrumentation, whose objectives have to be discussed in terms of anatomical landmarks and/or additional clinical information. The question of “hard” or “soft” image co-registration remains open, involving not only CT, but also SPECT or MRI. Development of dedicated imaging devices, whether single photon or positron, is of major interest for breast imaging, allowing optimal imaging conditions, with results definitely superior to classical gamma-cameras or PET. The patient population concerned with scintimammography is still controversial, as well as the imaging modalities: FDG or sestaMIBI, planar or tomographic, scintillators or semi-conductors, and the research field remains open. This is also valid for external or per-operative probe systems for tumor or lymph nodes localization.

Thequestion of whether pediatric and adult neuroimaging data can be analyzed in a common stereotactic space is a critical issue for developmental neuroscience. Two studies were performed to address this question. In Study 1, high-resolution structural MR brain images of 20 children (7–8 years of age) and 20 young adults (18–30 years of age) were transformed to a common space. Overall brain shape was assessed by tracing the outer boundaries of the brains in three orientations, and more local anatomy was assessed by analysis of portions of 10 selected sulci. Small, but consistent, differences in location and variability were observed in specific locations of the sulcal tracings and outer-boundary sections. In Study 2, a computer simulation was used to assess the extent to which the small anatomical differences observed in Study 1 would produce spurious effects in functional imaging data. Results indicate that, assuming a functional resolution of 5 mm in images averaged across subjects, anatomical differences in either variability or location between children and adults of the magnitude observed in Study 1 would not negatively affect functional image comparisons. We conclude that atlas-transformed brain morphology is relatively consistent between 7- and 8-year-old children and adults at a resolution appropriate to current functional imaging and that the small anatomical differences present do not limit the usefulness of comparing child and adult functional images within a common stereotactic space.

We built a low-cost system for monitoring human skin conductance responses (SCRs) in a clinical magnetic resonance (MR) scanner during functional imaging. The average scanner-induced conductance noise level was suppressed sufficiently to allow SCR measurements over the full range of SCR amplitudes, and functional image signal-to-noise ratio was unaffected by the skin conductance apparatus. The system may be useful for a variety of imaging studies. J. Magn. Reson. Imaging 2001;14:187–193. © 2001 Wiley-Liss, Inc.

Positron emission tomography (PET) builds images based on the biological processes of the body. It is, therefore, a ‘functional’ rather than an ‘anatomical’ imaging modality. Positron-emitting radionuclide labelled physiological molecules are injected intravenously. One of the more frequently used radiopharmaceuticals is fluorine-18 labelled deoxyglucose (FDG). The differential uptake of FDG by different cells of the body after its administration gives rise to a functional image. Currently, FDG-PET is used most often in neurological science, cardiology and oncology. Malignant cells are known to have a higher rate of glycolysis and, therefore, FDG uptake would be higher in cancer cells. Malignancies in various organs have been investigated with FDG-PET. To date, FDG-PET has been found useful for detecting tumours, staging and grading tumours, differentiating between recurrences and benign effects of treatment, monitoring the response to treatment, and assessing tumour drug uptake. Nevertheless, local data on PET are currently not available and its cost-effectiveness also needs further investigation.

Respiratory motion can potentially reduce accuracy in anatomic and functional image fusion from multimodality systems. It can blur the uptake of small lesions and lead to significant activity underestimation. Solutions presented to date include respiration-synchronized anatomic and functional acquisitions. To increase the signal-to-noise ratio of the synchronized PET images, methods using nonrigid transformations during the reconstruction process have been proposed. In most of these methods, 4-dimensional (4D) CT images were used to derive the required deformation matrices. However, variations between acquired 4D PET and corresponding CT image series due to differences in respiratory conditions during PET and CT acquisitions have been reported. In addition, the radiation dose burden resulting from a 4D CT acquisition may not be justifiable for every patient. Methods: In this paper, we present a method for the generation of dynamic CT images from the combination of one reference CT image and deformation matrices obtained from the elastic registration of 4D PET images not corrected for attenuation. On the one hand, our approach eliminates the need for the acquisition of dynamic CT. On the other hand, it also ensures a good match between CT and PET images, allowing accurate attenuation correction to be performed for respiration-synchronized PET acquisitions. Results: The proposed method was first validated on Monte Carlo–simulated datasets, and then on patient datasets (n = 4) by comparing generated 4D CT images with the corresponding acquired original CT images. Different levels of PET image statistical quality were considered in order to investigate the impact of image noise in the derivation of the 4D CT series. Conclusion: Our results suggest that clinically relevant PET acquisition times can be used for the implementation of such an approach, making this an even more attractive solution considering the absence of the extra dose given by a standard 4D CT acquisition. Finally, this approach may be applicable to other multimodality devices such as PET/MR.

Objective : Our goal was to present the first echo-volumar brain images obtained at 3.0 T, together with the first functional imaging results using echo volumar imaging. Materials and Methods : The results presented were obtained on volunteers using an in-house designed and constructed 3.0 T echo-planar/volumar imager. Results : The results demonstrate the feasibility of obtaining snapshot volumar images comprising up to 64 x 64 x 8 voxels corresponding to a spatial resolution of 3.0 x 3.0 x 2.5 mm 3 . Results are also presented showing local cortical changes in signal in response to an external visual stimulus for both the left and the right brain hemispheres. Conclusion : The snapshot acquisition of a whole-volume data set has a number of advantages when considering motional effects or functional image changes that may involve time delays or phase effects within different cortical regions. Instantaneous acquisition of the whole data set means accurate phase information may be straightforwardly obtained.

Having reviewed traditional Chinese views of Nature and ways of thinking, the struggle for survival of native knowledge when it encountered the challenge of Western science, and, the reflection of the struggle in the field of Chinese science education, the book now moves to describe an empirical study which looked at the functional image of science held by a group of Chinese secondary school science teachers. The study focused on how the teachers view the culture-embedded nature of science.

A functional image of the extensor digitorum muscle was obtained using the frequency domain spectroscopic technique with near-infrared light. The muscle was imaged by measuring the change in phase angle of modulated waves of near-infrared light in response to increased absorption of deoxygenated hemoglobin, which resulted from increased O2 metabolism during arm exercise. The image was compiled from a raster scan of flexion and relaxation exercises at 95 separate points on the dorsal surface of the right forearm. Each point on the arm consisted of a complete experiment that included continuous frequency-domain measurements of phase and intensity during rest, isotonic exercise, and recovery from exercise. Analysis consisted of a simple subtraction of the average phase angle baseline at rest from the average phase reading during steady-state contraction of the extensor digitorum muscle. A difference array of data was then compiled from these 95 experiments to give a 2-D density-plot image. The image clearly demonstrates the extensor digitorum muscle in its oblique position within the density-plot array. This experiment shows the in vivo functional imaging capability of the frequency-resolved technique and indicates that a high degree of resolution is obtainable.

Delayed detection of an internal hemorrhage may result in serious disabilities and possibly death for a patient. Currently, there are no portable medical imaging instruments that are suitable for long-term monitoring of patients at risk of internal hemorrhage. Electrical impedance tomography (EIT) has the potential to monitor patients continuously as a novel functional image modality and instantly detect the occurrence of an internal hemorrhage. However, the low spatial resolution and high sensitivity to noise of this technique have limited its application in clinics. In addition, due to the circular boundary display mode used in current EIT images, it is difficult for clinicians to identify precisely which organ is bleeding using this technique. The aim of this study was to propose an optimized strategy for EIT reconstruction to promote the use of EIT for clinical studies, which mainly includes the use of anatomically accurate boundary shapes, rapid selection of optimal regularization parameters and image fusion of EIT and computed tomography images. The method was evaluated on retroperitoneal and intraperitoneal bleeding piglet data. Both traditional backprojection images and optimized images among different boundary shapes were reconstructed and compared. The experimental results demonstrated that EIT images with precise anatomical information can be reconstructed in which the image resolution and resistance to noise can be improved effectively.

(Purpose) To investigate the incorporation of functional lung image-derived low attenuation area (LAA) based on four-dimensional computed tomography (4D-CT) into respiratory-gated intensity-modulated radiation therapy (IMRT) or volumetric modulated arc therapy (VMAT) in treatment planning for lung cancer patients with chronic obstructive pulmonary disease (COPD). (Materials and Methods) Eight lung cancer patients with COPD were the subjects of this study. LAA was generated from 4D-CT data sets according to CT values lower than -860 Hounsfield units (HU) as a threshold. The functional lung image was defined as the area where LAA was excluded from the image of the total lung. Two respiratory-gated radiotherapy plans (70 Gy/35 fr) were designed and compared in each patient as follows: 1) Plan A: anatomical IMRTor VMAT plan based on the total lung 2) Plan F: functional IMRT or VMAT plan based on the functional lung. Dosimetric parameters (V20: the percentage of total lung volume irradiated with ≥ 20 Gy,MLD:mean dose of total lung) of the two plans were compared. (Results) V20 was lower in Plan F than in Plan A (mean 1.5 %, p= 0.025 in IMRT, mean 1.6 %, p= 0.044 in VMAT) achieved by a reduction in MLD (mean 0.23 Gy, p= 0.083 in IMRT, mean 0.5 Gy, p= 0.042 in VMAT). No differences were noted in target volume coverage and organ-at-risk doses. (Conclusions) Functional image-guided radiotherapy planning based on LAAin respiratory-guided IMRT or VMAT appears to be effective in preserving a functional lung in lung cancer patients with COPD., This work was supported in part by a Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan (Grant no. 22591385), and a Grant-in-Aid for Scientific Research from the Association for Nuclear Technology in Medicine. This work was partly presented at the 52nd Annual Meeting of the American Society of Radiation Oncology, San Diego, CA, Oct 31 - Nov 4, 2010.

It is important to make a diagnosis before a low-density area appears on computed tomography for appropriate management of acute ischemic stroke. We report the diagnostic and prognostic usefulness of functional image of dynamic computed tomography for acute ischemic stroke. Forty-seven patients with ischemic strokes within 6 hours of ictus underwent dynamic computed tomography in which functional images were obtained. These findings were compared with angiographic findings, follow-up computed tomography, and clinical outcome. The functional images were categorized into three groups: (1) cortical type: abnormalities on time to peak image and/or corrected mean transit time image involving mainly cortical structures (29 cases); (2) noncortical type: abnormalities on either or both images limited to noncortical structures (7 cases); and (3) normal type: no abnormalities on both images (11 cases). Cortical type as a diagnostic test for arterial trunk occlusion had a good sensitivity (100%), specificity (95%), and accuracy (98%). Infarction volume on follow-up computed tomography correlated with extension of prolonged time-to-peak area (r = .80, P < .01) and that of prolonged corrected mean transit time area (r = .81, P < .01). Cortical type was associated with significantly unfavorable outcome (P < .01). Functional image of dynamic computed tomography findings predicted arterial trunk occlusion, infarction volume, and clinical outcome. Therefore, this technique would be useful not only for indicating definitive angiography and subsequent therapy but for evaluating the effectiveness of surgical or medical recanalization.

Life on earth has evolved in a sea of natural electromagnetic (EM) fields. Over the past century, this natural environment has sharply changed with introduction of a vast and growing spectrum of man-made EM fields. From models based on equilibrium thermodynamics and thermal effects, these fields were initially considered too weak to interact with biomolecular systems, and thus incapable of influencing physiological functions. Laboratory studies have tested a spectrum of EM fields for bioeffects at cell and molecular levels, focusing on exposures at athermal levels. A clear emergent conclusion is that many observed interactions are not based on tissue heating. Modulation of cell surface chemical events by weak EM fields indicates a major amplification of initial weak triggers associated with binding of hormones, antibodies, and neurotransmitters to their specific binding sites. Calcium ions play a key role in this amplification. These studies support new concepts of communication between cells across the barriers of cell membranes; and point with increasing certainty to an essential physical organization in living matter, at a far finer level than the structural and functional image defined in the chemistry of molecules. New collaborations between physical and biological scientists define common goals, seeking solutions to the physical nature of matter through a strong focus on biological matter. The evidence indicates mediation by highly nonlinear, nonequilibrium processes at critical steps in signal coupling across cell membranes. There is increasing evidence that these events relate to quantum states and resonant responses in biomolecular systems, and not to equilibrium thermodynamics associated with thermal energy exchanges and tissue heating.

We propose a segmentation method for blurred and low-resolution CT images focusing physical properties. The basic idea of our research is simple: two objects can be easily separated in areas of structural weakness. Given CT images of an object, we assign a physical property such as Young's modulus to each voxel and create functional images (e.g., von Mises strain at the voxel). We then remove the voxel with the largest value in the functional image, and these steps are reiterated until the input model is decomposed into multiple parts. This simple and unique approach provides various advantages over conventional segmentation methods, including preciousness and noise robustness. This paper also demonstrates the efficiency of our approach using the results of various types of CT images, including biological representations and those of engineering objects.

A SWT based variable-weights selection scheme is proposed to merge the gray structural image and its corresponding color functional image for the localization of the protein in the biological community. After decomposing the original image by the stationary wavelet transform (SWT), multi- scaled transparencies are assigned for each pixel according to its SWT values. Then the fused product is generated by the inverse wavelet transform (ISWT) with multi-scaled transparencies. 117 groups of images are assessed by means of quantitative tests. Quantified indexes related with the fused product and original images are respectively calculated for the functional and non- functional area. Experimental results for several traditional image fusion methods indicate advantages of the proposed method.

We present a novel analysis to quantify the eye movement from functional magnetic resonance (fMRI) data without the aid of dedicated eye-trackers. We show that by using the parts of the functional image data that contain the motion artefacts of the subject's eyes and by applying spatial independent component analysis to it, it is possible to detect eye movement and to estimate the point of gaze at the time of the data acquisition.

Publisher Summary This chapter discusses the advantages and limitations of 18F-fluorodeoxyglucose positron emission tomography (18FDG PET) in the assessment of cancer. 18FDG PET has become the cornerstone for the management of many patients suffering from cancer; it provides a functional image of the underlying changes of glucose metabolism in normal and abnormal tissues. Because most malignancies exhibit increased glucose metabolism, whole-body 18FDG PET reflects a certain degree of tumor aggressiveness in terms of glucose tracer avidity and disease extent. This allows the evaluation of biochemical tumor changes, which may take place early in the malignant process as well as in the course of tumor response to treatment. 18FDG PET relies on the coincidental detection of two annihilation photons, which significantly improves the spatial resolution and the sensitivity compared to conventional single photon emission tomography (SPECT). 18FDG PET is a flexible imaging technique that may be readily performed in any clinical environment. 18FDG PET is a safe and noninvasive imaging procedure, which allows the performance of a highly sophisticated examination with a minimal inconvenience for the patient and allows a whole-body imaging that enables the exploration of anatomic regions.. 18FDG is not a tumor-specific tracer and is limited for detection of abnormal uptakes to regions of the body with a high physiological background.

The combination of cardiac viability and functional information enhances the identification of different heart tissues in the setting of ischemic heart disease. A method has recently been proposed for obtaining black-blood delayed-enhancement (DE) viability images using the stimulated-echo acquisition mode (STEAM) MRI pulse sequence in a single short breathhold. The method was validated against conventional inversion-recovery (IR) DE images for identifying regions of myocardial infarction (MI). The method was based on the acquisition of three consecutive images of the same anatomical slice. One image has T(1)-weighted contrast in which infarction appears bright. The two other images are used to construct an anatomical image of the heart, which is combined with the first image to produce a black-blood viability image. However, using appropriate modulation and demodulation frequencies, the latter two images bear useful information about myocardial deformation that results in a cardiac strain-encoding (SENC) functional image. In this work, a method is proposed for obtaining three consecutive SENC images in a single acquisition that can be combined to produce a composite image of the heart, which shows both functional and viability information. The proposed technique reduces scan time by one-half, compared with separate acquisitions of functional and viability images, and alleviates misregistration problems caused by separate breathholds.

This study applies image registration techniques to combine functional and structural information derived from multi-modal magnetic resonance imaging in patients diagnosed with brain gliomas. The images vary substantially in resolution, signal-to-noise ratio, information content and field of view and therefore pose a challenging registration problem. Specific protocols have been designed for each registration task, with careful selection of critical parameters and appropriate pre-processing. In addition, we have developed a visual assessment protocol to evaluate the accuracy of the proposed methods. Preliminary results suggest that registrations errors are below the functional image resolutions, thus achieving sub-voxel accuracy.

Typical packages used for coregistration in functional image analyses include automated image registration (AIR) and statistical parametric mapping (SPM). However, both methods have limited-dimension deformation models. A fully deformable model, which combines the piecewise linear registration for coarse alignment with demons algorithm for voxel-level refinement, allows a higher degree of spatial deformation. This leads to a more accurate colocalization of the functional signal from different subjects and therefore can produce a more reliable group average signal. We quantitatively compared the performance of the three different registration approaches through a series of experiments and we found that the fully deformable model consistently produces a more accurate structural segmentation and a more reliable functional signal colocalization than does AIR or SPM.