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Seminars in Nuclear Medicine Jan 2012Single-photon emission computed tomography (SPECT) has been a significant advancement in scintigraphy, impacting many areas of diagnosis. It has begun to find use in... (Review)
Review
Single-photon emission computed tomography (SPECT) has been a significant advancement in scintigraphy, impacting many areas of diagnosis. It has begun to find use in ventilation-perfusion (V/Q) scintigraphy. However, its utility has been limited in the United States because of a lack of an optimal and Food and Drug Administration-approved SPECT ventilatory agent. Although SPECT V/Q can show more and smaller mismatches than planar studies, there is persistent debate regarding the clinical significance of these smaller pulmonary emboli (PE); they may be neither clinically significant nor require treatment. Available data suggest that planar V/Q, SPECT V/Q, and computed tomographic pulmonary angiography (CTPA) have similar false-negative rates and thus have a similar impact on outcomes. In most cases, emergency department physicians are the first to encounter patients who may have PE, and they frequently use an imaging study as part of the evaluation. We discuss the rational for triaging patients to different imaging modalities with the use of chest radiography and the strengths and weaknesses of each modality. Detailed anatomy is an advantage of CTPA, breast radiation dose is reduced with scintigraphy, and imaging is quicker and more detailed with SPECT. We also review planar and SPECT V/Q and CTPA from the differing vantage points of diagnostic accuracy vs patient outcomes. Whatever modality their patients require, physicians can be confident that they are all similarly efficacious at diagnosing clinically relevant emboli.
Topics: Humans; Image Interpretation, Computer-Assisted; Pulmonary Embolism; Radionuclide Imaging; Safety; Sensitivity and Specificity; Ventilation-Perfusion Ratio
PubMed: 22117808
DOI: 10.1053/j.semnuclmed.2011.07.003 -
Radiation Research Apr 2012The underlying principles of nuclear medicine imaging involve the use of unsealed sources of radioactivity in the form of radiopharmaceuticals. The ionizing radiations... (Review)
Review
The underlying principles of nuclear medicine imaging involve the use of unsealed sources of radioactivity in the form of radiopharmaceuticals. The ionizing radiations that accompany the decay of the administered radioactivity can be quantitatively detected, measured, and imaged in vivo with instruments such as gamma cameras. This paper reviews the design and operating principles, as well as the capabilities and limitations, of instruments used clinically and preclinically for in vivo radionuclide imaging. These include gamma cameras, single-photon emission computed tomography (SPECT) scanners, and positron emission tomography (PET) scanners. The technical basis of autoradiography is reviewed as well.
Topics: Animals; Autoradiography; Diagnostic Imaging; Equipment Design; Gamma Cameras; Humans; Mice; Molecular Imaging; Nuclear Medicine; Positron-Emission Tomography; Radiation, Ionizing; Radiobiology; Radiometry; Radionuclide Imaging; Radiopharmaceuticals; Rats; Sensitivity and Specificity; Tomography; Tomography, Emission-Computed, Single-Photon; Whole Body Imaging
PubMed: 22364319
DOI: 10.1667/rr2577.1 -
Cancer Biotherapy & Radiopharmaceuticals Feb 2002Radionuclide therapy extends the usefulness of radiation from localized disease of multifocal disease by combining radionuclides with disease-seeking drugs, such as... (Review)
Review
Radionuclide therapy extends the usefulness of radiation from localized disease of multifocal disease by combining radionuclides with disease-seeking drugs, such as antibodies or custom-designed synthetic agents. Like conventional radiotherapy, the effectiveness of targeted radionuclides is ultimately limited by the amount of undesired radiation given to a critical, dose-limiting normal tissue, most often the bone marrow. Because radionuclide therapy relies on biological delivery of radiation, its optimization and characterization are necessarily different than for conventional radiation therapy. However, the principals of radiobiology and of absorbed radiation dose remain important for predicting radiation effects. Fortunately, most radionuclides emit gamma rays that allow the measurement of isotope concentrations in both tumor and normal tissues in the body. By administering a small "test dose" of the intended therapeutic drug, the clinician can predict the radiation dose distribution in the patient. This can serve as a basis to predict therapy effectiveness, optimize drug selection, and select the appropriate drug dose, in order to provide the safest, most effective treatment for each patient. Although treatment planning for individual patients based upon tracer radiation dosimetry is an attractive concept and opportunity, practical considerations may dictate simpler solutions under some circumstances. There is agreement that radiation dosimetry (radiation absorbed dose distribution, cGy) should be utilized to establish the safety of a specific radionuclide drug during drug development, but it is less generally accepted that absorbed radiation dose should be used to determine the dose of radionuclide (radioactivity, GBq) to be administered to a specific patient (i.e., radiation dose-based therapy). However, radiation dosimetry can always be utilized as a tool for developing drugs, assessing clinical results, and establishing the safety of a specific radionuclide drug. Bone marrow dosimetry continues to be a "work in progress." Blood-derived and/or body-derived marrow dosimetry may be acceptable under specific conditions but clearly do not account for marrow and skeletal targeting of radionuclide. Marrow dosimetry can be expected to improve significantly but no method for marrow dosimetry seems likely to account for decreased bone marrow reserve.
Topics: Bone Marrow; Humans; Neoplasms; Radioisotopes; Radionuclide Imaging; Radiotherapy Dosage
PubMed: 11915167
DOI: 10.1089/10849780252824127 -
Seminars in Nuclear Medicine Jan 2014Nuclear scintigraphic examination of equine athletes has a potentially important role in the diagnosis of lameness or poor performance, but increased radiopharmaceutical... (Review)
Review
Nuclear scintigraphic examination of equine athletes has a potentially important role in the diagnosis of lameness or poor performance, but increased radiopharmaceutical uptake (IRU) is not necessarily synonymous with pain causing lameness. Nuclear scintigraphy is highly sensitive to changes in bone turnover that may be induced by loading and knowledge of normal patterns of RU is crucial for accurate diagnosis. Blood pool images can be useful for identification of some soft tissue injuries, although acute bone injuries may also have intense IRU in blood pool images. Some muscle injuries may be associated with IRU in bone phase images. The use of scintigraphy together with other diagnostic imaging modalities has helped us to better understand the mechanisms of some musculoskeletal injuries. In immature racehorses, stress-related bone injury is a common finding and may be multifocal, whereas in mature sport horses, a very different spectrum of injuries may be identified. False-negative results are common with some injuries.
Topics: Animals; Horse Diseases; Horses; Musculoskeletal System; Radionuclide Imaging; Radiopharmaceuticals; Sports
PubMed: 24314041
DOI: 10.1053/j.semnuclmed.2013.08.003 -
Compendium (Yardley, PA) Dec 2010Nuclear scintigraphy has been used successfully for various applications in horses in the past 30 years. Many private practices and most veterinary schools have gamma... (Review)
Review
Nuclear scintigraphy has been used successfully for various applications in horses in the past 30 years. Many private practices and most veterinary schools have gamma cameras, which are used to image an injected radionuclide in an equine patient. Unique exercise-related demands place specific physiologic stressors on the musculoskeletal system of horses. Horses are often pushed beyond normal physiologic limits because of specific performance stresses; therefore, injury to their musculoskeletal system is common. Skeletal scintigraphy is exceedingly sensitive but relatively nonspecific for determining a definitive etiology. Equine scintigraphy is best suited for detecting acute soft tissue and osseous abnormalities because radiopharmaceutical uptake often precedes radiographic detection. However, scintigraphy can also be used to locate potential areas of abnormal osseous turnover in horses with chronic, vague lameness. This article reviews the basic principles of equine scintigraphy, with an emphasis on bone scintigraphy and the clinical applications of this technique. Vascular-, soft tissue-, and bone-phase acquisition are described along with basic image interpretation. Potential pitfalls in image acquisition and interpretation are discussed.
Topics: Animals; Bone Diseases; Bone and Bones; Horse Diseases; Horses; Lameness, Animal; Nuclear Medicine; Radionuclide Imaging; Radiopharmaceuticals
PubMed: 21882163
DOI: No ID Found -
Seminars in Nuclear Medicine Mar 2012
Topics: Gastrointestinal Tract; Humans; Nuclear Medicine; Radionuclide Imaging
PubMed: 22293161
DOI: 10.1053/j.semnuclmed.2011.11.002 -
Hellenic Journal of Nuclear Medicine 2005
Topics: Europe; Greece; Humans; Neoplasms; Nuclear Medicine; Practice Patterns, Physicians'; Radionuclide Imaging; United States
PubMed: 15886750
DOI: No ID Found -
Cancer Biotherapy & Radiopharmaceuticals Dec 1999
Review
Topics: Breast Neoplasms; Female; Humans; Mammography; Radionuclide Imaging; Radiopharmaceuticals; Technetium Tc 99m Sestamibi
PubMed: 10850328
DOI: 10.1089/cbr.1999.14.417 -
Medical Progress Through Technology Jun 1980
Topics: Bone Neoplasms; Brain; Gamma Rays; Humans; Radionuclide Imaging
PubMed: 7393178
DOI: No ID Found -
JAMA Jun 1997
Topics: Cardiovascular Diseases; Heart; Humans; Neoplasms; Nuclear Medicine; Radioimmunodetection; Radionuclide Imaging; Radiopharmaceuticals; Radiotherapy; Tomography, Emission-Computed
PubMed: 9185811
DOI: No ID Found