AJR. American journal of roentgenology
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AJR Am J Roentgenol · Nov 2012
ReviewComprehensive MDCT evaluation of patients with suspected May-Thurner syndrome.
The purpose of this essay is to introduce the MDCT protocol and interpretation techniques for optimal evaluation of patients with suspected May-Thurner syndrome. ⋯ May-Thurner syndrome is always the working diagnosis when a patient presents with unilateral left lower limb swelling without signs of infection. MDCT is useful for fast, comprehensive evaluation of the vascular system to determine whether May-Thurner syndrome or an alternative condition is present.
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Various applications for dual-energy CT (DECT) have been investigated and have shown substantial clinical benefits. However, only limited data are available regarding the radiation dose associated with DECT imaging. The purpose of this article is to review the available literature regarding the radiation dose associated with DECT imaging applications in comparison with conventional single-energy CT techniques. ⋯ The rediscovery of DECT and the increasing availability of this technique on clinical CT systems have opened new dimensions for CT. The advanced spectral differentiation of materials within the human body as well as the selective visualization or subtraction of iodinated contrast material or xenon provides both advanced visualization of disease-specific molecular substrates as well as additional functional information within a single scan.
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AJR Am J Roentgenol · Nov 2012
Comparative StudyComparison of qualitative and quantitative evaluation of diffusion-weighted MRI and chemical-shift imaging in the differentiation of benign and malignant vertebral body fractures.
The objective of our study was to compare the diagnostic value of qualitative diffusion-weighted imaging (DWI), quantitative DWI, and chemical-shift imaging in a single prospective cohort of patients with acute osteoporotic and malignant vertebral fractures. ⋯ The DW-PSIF sequence (delta = 3 ms) had the highest accuracy in differentiating benign from malignant vertebral fractures. Quantitative chemical-shift imaging and quantitative DW single-shot TSE imaging had a lower accuracy than DW-PSIF imaging because of a large overlap. Qualitative assessment of opposed-phase, DW-EPI, and DW single-shot TSE sequences and quantitative assessment of the DW-EPI sequence were not suitable for distinguishing between benign and malignant vertebral fractures.
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AJR Am J Roentgenol · Nov 2012
Dual-energy CT: a promising new technique for assessment of the musculoskeletal system.
Dual-energy CT (DECT) characterizes the chemical composition of material according to its differential x-ray attenuation at two different energy levels. Applications of DECT in musculoskeletal imaging include imaging of bone marrow edema, tendons, and ligaments and the use of monoenergetic techniques to minimize metal prosthesis beam-attenuating artifacts. ⋯ The most validated application of DECT is undoubtedly its noninvasive and highly specific ability for confirming the presence of monosodium urate deposits in the assessment of gout.
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AJR Am J Roentgenol · Nov 2012
PET/CT of cancer patients: part 2, deformable registration imaging before and after chemotherapy for radiation treatment planning in head and neck cancer.
The purpose of this perspective is to discuss the use of deformable registration as a tool for image fusion to integrate information from PET/CT scans obtained before and after chemotherapy to assist definition of radiation targets in the management of head and neck cancer. ⋯ The consistent method for target delineation described capitalizes on the capability of deformable registration to compensate for changes in position and accurately represent evolving spatial relationships between normal anatomy and areas at risk of disease.