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Absolute quantification in SPECT
Absolute quantification in SPECT

... distribution of the attenuation coefficients of the examined object for the photon energy of the radionuclide used needs to be known. Several methods for obtaining attenuation maps have been employed. The maps can be estimated, if the contours of the object (e.g. via rough segmentation of the SPECT ...
Rapid MRI Detection of Vertebral Numeric Variation
Rapid MRI Detection of Vertebral Numeric Variation

... were reconfirmed by referencing additional conventional MRI sequences acquired as part of the clinical MRI examination. The data were compiled and compared. The final examination report was then referenced to determine whether the vertebral variation was identified and documented by the fellowship-t ...
Magnetic Resonance Spectroscopy
Magnetic Resonance Spectroscopy

... recommendations applicable to newly diagnosed lesions with a suspected or histopathologically proven LGG. Studies identified regarding MRS diagnostic specificity were all of Class III evidence, that is, data is provided by expert opinion or studies that do not meet the criteria for the delineation ...
Enhancement of Focal Liver Lesions at Gadoxetic Acid–enhanced
Enhancement of Focal Liver Lesions at Gadoxetic Acid–enhanced

... consent (one of 63), or a dose lower (0.0125 mmol/kg) or higher (0.05 mmol/ kg) than the clinical dose was used in patients examined during the phase II study (15 of 23 patients). ...
A Guide to CT Radiation Dose Management
A Guide to CT Radiation Dose Management

... knowledge of radiation physics. However, it is important that all have a basic understanding in order to be able to speak with patients and referring physicians. This chapter presents an explanation of the terminology used by medical physicists to estimate a patient’s radiation dose, and methods to ...
Integrated cardiovascular imaging.
Integrated cardiovascular imaging.

... Aortic dissection Post cardiac injury  syndromes (MI, post  pericardiotomy, traumatic  iatrogenic or not) ...
CT Dosimetry: Com- parison of Measure- ment
CT Dosimetry: Com- parison of Measure- ment

... John A. Bauhs, PhD ● Thomas J. Vrieze, RT(R) ● Andrew N. Primak, PhD ● Michael R. Bruesewitz, RT(R) ● Cynthia H. McCollough, PhD In x-ray computed tomography (CT), the most common parameter used to estimate and minimize patient dose is the CT dose index (CTDI). The CTDI is a volume-averaged measure ...
Winnovative HTML to PDF Converter for .NET
Winnovative HTML to PDF Converter for .NET

... data transmission. All have provided arduous technical challenges, several of which remain unresolved.     The greatest challenge in detector development was the size and spatial resolution. Several solid-state detectors were available, but the problem was to design one that could produce a full ima ...
Imaging of the Female Pelvis: Evaluation of a Submucosal Rectal Mass
Imaging of the Female Pelvis: Evaluation of a Submucosal Rectal Mass

... Gillian Lieberman, MD Mary Kwaan, MD ...
Recent developments in coronary computed tomography imaging
Recent developments in coronary computed tomography imaging

... a temporal resolution in a mono-segmental halfscan reconstruction appear to be beyond today’s mechanical limits (i.e., >75 g) [2] . In addition, in order to compensate for motion artifacts at higher heart rates, two- or multisegment reconstruction algorithms are used that merge data from two or more ...
Application of Partial Volume Effect Correction and 4D PET in the
Application of Partial Volume Effect Correction and 4D PET in the

... also examined factors, which can affect quantification accuracy, including the size of lesion and the location of tumor. Results: This study showed that quantification of volumetric parameters of 4D PET/CT images using an adaptive contrast-oriented thresholding algorithm and 3D lesion-based partial vo ...
Nigerian Radiation Safety in Diagnostic and Interventional
Nigerian Radiation Safety in Diagnostic and Interventional

... Ionizing Radiation Regulations and exposures from practi~es. or sources exempted by the Nigeria Basic Ionizing Radiation Regulations; "personal dose equivalent ", Hp(d) means the dose equivalent in soft tissue below a specified point on the body at the appropriate depth. (The relevant depths for the ...
Can Clinically Significant Prostate Cancer Be Detected with
Can Clinically Significant Prostate Cancer Be Detected with

... Context: Detection of clinically significant prostate cancer (PCa) is a major challenge. It has been shown that multiparametric magnetic resonance imaging (mpMRI) facilitates localisation of PCa and can help in targeting prostate biopsy. Objective: To systematically review the literature to determin ...
Time-resolved projection angiography after bolus injection of
Time-resolved projection angiography after bolus injection of

... across the projection direction. Depending on the overall field inhomogeneity and on local susceptibility effects, the signal from within the vessels is not necessarily in phase signal from the background. For generating subtraction angiograms, this problem can be alleviated using complex subtractio ...
Chapter 8: Fluoroscopic Imaging Systems
Chapter 8: Fluoroscopic Imaging Systems

... Flat panels therefore require higher IAKR than XRII-based systems for fluoroscopic imaging Conversely, flat panels perform better than XRIIs at high IAKR, such as those used during Digital Acquisition Imaging The appearance of image noise in fluoroscopy is also influenced by Human Perception For exa ...
IOSR Journal of Dental and Medical Sciences (IOSR-JDMS)
IOSR Journal of Dental and Medical Sciences (IOSR-JDMS)

... Studdiford’s criteria with the use of transvaginal and transabdominal ultrasound examination. We found both fallopian tubes and ovaries intact. With regard to the second criterion, we did not observe any uteroplacental fistulae in our case. Since abdominal pregnancy at less than 20 weeks of gestatio ...
SPECT and PET Serve as Molecular Imaging Techniques
SPECT and PET Serve as Molecular Imaging Techniques

... (single photon emission computerized tomography) or PET (positron emission tomography) scanners. To image brain metastases many radiopharmaceuticals, either gamma or positron emitters, are available. Although contrast-enhanced magnetic resonance imaging (MRI) represents the option of choice to inves ...
Examples-for-Preventice-Meeting
Examples-for-Preventice-Meeting

... streamlining routine scans, the Optima MR360 incorporates an express exam approach to MR. It includes many intuitive and automated functions that help increase patient comfort, operator confidence, image consistency, and professional satisfaction of MR staff. ...
What is the definition of albedo?
What is the definition of albedo?

... source of x-rays, which resulted in sharper images. The tube had a third electrode, an anticathode connected to the anode. It improved the X-ray output, but the method by which it achieved this is not understood. A more common arrangement used a cupped plate anticathode (similar in constriction to t ...
Clarify Distance Source to Patient in Mammo and CR
Clarify Distance Source to Patient in Mammo and CR

... Imaging Subject, but accounts for what is realistically measurable in an automated fashion in a clinical setting. 2. This measurement does not take into account any air gap between the Imaging Subject and the “front” of the table or bucky. 3. If the detector is not mounted in a table or bucky, then ...
Patient Dose in common CT examinations-2003
Patient Dose in common CT examinations-2003

... European Commission (EC) have all recommended the setup and the implementation of CT dose guidance levels for the most frequent examinations to promote strategies for the optimization of CT doses3. These dose guidance levels should be derived using data from a wide scale survey. Therefore, it is of ...
Diffusion-weighted MR Imaging Offers No Advantage over Routine
Diffusion-weighted MR Imaging Offers No Advantage over Routine

... of 165 s/mm2 because it results in optimal signalto-noise ratio within a clinically acceptable time frame (4). This is important because, in many patients with metastases to the spine, the entire spine needs to be imaged, leading to a lengthy examination. Although this b value is relatively low, it ...
Common Reflection Angle Migration for Improved Imaging
Common Reflection Angle Migration for Improved Imaging

... change, through rays which are traced from subsurface reflectors to the surface. In grid tomography the updates are calculated on a spatial grid which is generally coarser than the velocity volume. After the calculations are completed, the updates are interpolated to the size of velocity parameter g ...
Click here for handout
Click here for handout

... Poor electrocardiogram gating Breathing motion Patient movement ...
Kidneys and Adrenal Glands
Kidneys and Adrenal Glands

... ly occur in the kidney. In most cases, they result in dilatation of the calices and/or the pelvis, depending on where the neoplasm is located. Conventional MR images do not have great sensitivity for the identification of uroepithelial carcinomas; these are better identified by means of MR urography ...
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Image-guided radiation therapy

Image-guided radiation therapy (IGRT) is the process of frequent two and three-dimensional imaging, during a course of radiation treatment, used to direct radiation therapy utilizing the imaging coordinates of the actual radiation treatment plan. The patient is localized in the treatment room in the same position as planned from the reference imaging dataset. An example of IGRT would include localization of a cone beam computed tomography (CBCT) dataset with the planning computed tomography (CT) dataset from planning. IGRT would also include matching planar kilovoltage (kV) radiographs or megavoltage (MV) images with digital reconstructed radiographs (DRRs) from the planning CT. These two methods comprise the bulk of IGRT strategies currently employed circa 2013.This process is distinct from the use of imaging to delineate targets and organs in the planning process of radiation therapy. However, there is clearly a connection between the imaging processes as IGRT relies directly on the imaging modalities from planning as the reference coordinates for localizing the patient. The variety of medical imaging technologies used in planning includes x-ray computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) among others. The precision of IGRT is significantly improved when N-localizer technology is used in conjunction with these medical imaging technologies. Through advancements in imaging technology, combined with a further understanding of human biology at the molecular level, the impact of IGRT on radiotherapy treatment continues to evolve.
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