Veterinary radiology & ultrasound : the official journal of the American College of Veterinary Radiology and the International Veterinary Radiology Association
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Vet Radiol Ultrasound · Mar 2014
ReviewInvited review--neuroimaging response assessment criteria for brain tumors in veterinary patients.
The evaluation of therapeutic response using cross-sectional imaging techniques, particularly gadolinium-enhanced MRI, is an integral part of the clinical management of brain tumors in veterinary patients. Spontaneous canine brain tumors are increasingly recognized and utilized as a translational model for the study of human brain tumors. However, no standardized neuroimaging response assessment criteria have been formulated for use in veterinary clinical trials. ⋯ The widely used human Macdonald and response assessment in neuro-oncology (RANO) criteria are reviewed and described as to how they can be applied to veterinary brain tumors. Discussion points will include current challenges associated with the interpretation of brain tumor therapeutic responses such as imaging pseudophenomena and treatment-induced necrosis, and how advancements in perfusion imaging, positron emission tomography, and magnetic resonance spectroscopy have shown promise in differentiating tumor progression from therapy-induced changes. Finally, although objective endpoints such as MR imaging and survival estimates will likely continue to comprise the foundations for outcome measures in veterinary brain tumor clinical trials, we propose that in order to provide a more relevant therapeutic response metric for veterinary patients, composite response systems should be formulated and validated that combine imaging and clinical assessment criteria.
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Vet Radiol Ultrasound · Mar 2001
ReviewNormal duplex Doppler waveforms of major abdominal blood vessels in dogs: a review.
The normal flow velocity profile and duplex Doppler waveform of the major abdominal blood vessels (aorta, caudal vena cava and the portal vein as well as their major branches) were examined by Doppler ultrasound. The flow velocity profile of an artery is largely determined by its diameter. ⋯ The waveform of the veins is mainly affected by the pressure conditions of the right atrium and the intrathoracic and intraabdominal pressure changes due to the respiration. Simultaneous electrocardiogram was used to reveal the effect of the heart beats on the Doppler patterns of the veins.
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Vet Radiol Ultrasound · Jan 1997
ReviewA review of sonographic identification of abdominal blood vessels and juxtavascular organs.
Abdominal vasculature can be evaluated non-invasively using 2-D ultrasound imaging and Doppler ultrasonography. The identification of abdominal vessels using ultrasound is based on knowledge of their normal location, appearance and relationship to specific organs. Because anatomic location of major abdominal vessels is fairly consistent, finding and following vessels is a useful aid when attempting to locate and evaluate juxta-vascular organs. ⋯ This includes the sonographic appearance of the aorta, caudal vena cava, and protal vein, their major branches and their anatomic relationship with adjacent organs. Identification of the medial iliac lymph nodes, mesenteric lymph nodes, abdominal esophagus, duodenum, spleen, kidneys, pancreas, adrenal glands and liver lobes are assisted by recognizing specific vascular landmarks. The locations and appearances of pertinent organs as pertains to abdominal vasculature (caudal vena cava and aorta) are described.