Emission computerized tomography: Clinical applications (original) (raw)
Related papers
Acta Radiologica, 1988
A clinical application of a previously developed technique for absolute quantitation of organ uptake of radioactivity is presented. The method, which is based on single photon emission computed tomography involving correction for scattering and attenuation of photons, enables an accurate in vivo determination of the amount of administered activity taken up in a specific organ. The technique was applied to a comparative clinical trial between propanetetraphosphonate and albumin colloid for liver and spleen scintigraphy. The mean uptake of the liver was 73 +/- 9 per cent using propanetetraphosphonate and 63 +/- 10 per cent using albumin colloid. The corresponding figures for the spleen were 6 +/- 3 and 9 +/- 4 per cent, respectively. The activity concentration of the different lobes of the liver, bone marrow and soft tissue was also estimated. Phantom studies showed that the total uptake in the liver could be determined with an accuracy of about 6 per cent. The accuracy of the clinical examinations was estimated to about 10 per cent.
Determination of organ volume by single-photon emission tomography
Journal of nuclear medicine : official publication, Society of Nuclear Medicine, 1982
A method for estimation of organ volume is proposed, based on analysis of individual slices obtained from SPET images. In a phantom simulating clinical circumstances, the data show that the level a threshold at 46% of the maximum activity predicts most closely the true volume over a wide range above one liter. The level at 45% predicted better volumes of less than one liter. For phantoms of 839 ml or less, the error was 6.3 ml (one standard error of estimation). This level seems to be independent of the plane or position of the phantom and also independent of the amount of scattering material around it. Nonradioactive voids ("holes") within a phantom may be included or excluded at will when their edges are not tangent to the edge of the phantom. In such cases, their edges are not distinguishable from the edge of the phantom and their volumes are excluded. Knowledge of organ volumes has both diagnostic and therapeutic importance and could lead to a more precisely quantitate...
Neuro-Oncology Single-Photon Emission CT: A Current Overview
Neurographics, 2011
There is increasing need for noninvasive biomarkers for glioma treatment-response evaluation and for distinguishing tumor progression and recurrence from treatment-related changes. Here, SPECT, particularly 201Tl SPECT, plays an important role. SPECT takes advantage of glioma cellular make-up. Specifically, Na+>/K+ pump expression, mitochondrial attenuation, and amino acid transporter expression are probed with 201Tl, 99mTc-MIBI, and 123IMT radiotracers respectively. 201Tl can be used to distinguish brain tumors and nontumors and to determine brain tumor type and grade gliomas. However, it is especially valuable in the detection of tumor recurrence in patients treated with radiation therapy for supratentorial glioma. Similarly, 99mTc-MIBI can be used to distinguish recurrence from treatment residua. 99mTc-TF is comparable with 99mTc-MIBI, and both may allow clear identification of tumor boundaries. 123IMT appears to be superior to 99mTc-MIBI in determining tumor recurrence and is particularly promising in detecting LGG recurrence. Additionally, 123IMT shows promise in treatment planning where there is a survival advantage. LGGs frequently express somatostatin receptors; however, because radiolabeled somatostatin analogs do not cross the BBB and because LGGs frequently do not disturb the BBB, somatostatin-receptor imaging is limited in glioma imaging. Among the non-natural amino acid class, 123IPA is not preferable to the more established 123IMT. In summary, most international experience by using SPECT is with 201Tl; however, other radiotracers are used with good effect in some clinics.
Tomographic Methods in Nuclear Medicine: Physical Principles, Instruments, and Clinical Applications
2020
The introduction of computed tomography in the early 1970s had a profound influence on nuclear medicine. First, it drove "nukes" from static imaging of organs into dynamic studies of physiology, especially in the heart. Second, it gave credence to the computer as an integral part of imaging systems, so much in fact that a revolution in all approaches to diagnostic imaging has occurred over the last 15 years. These two influences combined initially to stimulate the evolution of cardiovascular nuclear medicine, and subsequently the development of tomogra phic techniques for nuclear imaging. Computed tomography was the first successful application of reconstruction mathematics to tomographic imaging. Perhaps its most significant influence was that computed tomography captured the imagination of several bright and ingenious young physicians, physicists, and engineers, whose contributions over the past few years have yielded such clinical breakthroughs as magnetic resonance imaging, digital angiography, digital radiography, real-time ultrasound, and single photon and positron emission tomography. It has been an exciting 15 years. Yet many challenges remain, including several which may be particularly amenable to tomographic nuclear imaging. Most of these challenging applica tions are discussed in this text, and I shall mention only one in this Foreword. This single application has such potential that its realization could help millions of people and save billions of dollars in health care costs. In addition, it could open a multitude of promising avenues of research. The 1990s have been described by several savants as the "Era of the Neurosciences" and "Decade of the Brain". Advances in understanding of fundamental biochemical and neurophysical mechanisms in the brain promise ultimately to yield new ways for diagnosis of mental diseases and conditions, and novel approaches for their treatment. Early intervention in these problems, and perhaps even prevention in some cases, may evolve from knowledge gained in basic science laboratories and applied in clinical settings where the appropriate diagnostic tools are available. Tomographic techniques in nuclear medicine promise to be among the pivotal tools needed to realize these advances. No one entering or working in diagnostic imaging today can afford to remain ignorant of the techniques of nuclear tomographic imaging, or of the scientific and technical base from which they evolve. These techniques are at the leading edge of some of the most exciting research arenas in medical and biomedical research, and their importance to clinical medicine will undoubtedly be even greater in the future than they are today. Consequently, I am very pleased that Dr. Ahluwalia has compiled this text which offers a breadth of coverage of nuclear tomography that is unavailable in other texts on nuclear imaging.
Pictorial review of SPECT/CT imaging applications in clinical nuclear medicine
American journal of nuclear medicine and molecular imaging, 2012
Integrated SPECT/CT scanners are gaining popularity as hybrid molecular imaging devices which can acquire SPECT and CT in a single exam. CT can be a low dose non-contrast enhanced scan for attenuation correction and anatomical localization, or a contrast enhanced diagnostic quality scan for additional anatomical characterization. We present a pictorial review highlighting the usefulness of this emerging technology. We present SPECT/CT images of 13 patients where additional information was provided by the co-registered low dose non-contrast enhanced CT scan. They belong to 12 male and 1 female patients with age ranging from 28 to 76 yrs, who were referred to the Nuclear Medicine Department for various indications. We describe these cases under in the following categories: bone scintigraphy (2), leukocyte scintigraphy (2), nuclear oncology (5), nuclear cardiology (1), and general nuclear medicine (3). Additional information provided by the co-registered low dose CT improves the diagno...
2006
Regional brain perfusion can be estimated with dy namic imaging and equilibrium flow imaging using diffusible or extractable tracers (1 ). Investigators have used a number of positron emitters including krypton, ammonia, carbon-i 1 dioxide, and rubidium, along with transaxial emission computed tomography, to assess regional brain perfusion (2—6). The results obtained with these positron techniques have stimulated efforts to de velop single-photon radiopharmaceuticals that are free of the high technology cost of positron tomography, es timated at $1,700 per study, which has limited the use of regional brain perfusion imaging to a few centers (personal communication, TF Budinger).
Cancer Imaging, 2012
We have previously reported on a method for reconstructing quantitative data from 99m Tc single photon emission computed tomography (SPECT) images based on corrections derived from X-ray computed tomography, producing accurate results in both experimental and clinical studies. This has been extended for use with the radionuclide 201 Tl. Accuracy was evaluated with experimental phantom studies, including corrections for partial volume effects where necessary. The quantitative technique was used to derive standardized uptake values (SUVs) for 201 Tl evaluation of brain tumours. A preliminary study was performed on 26 patients using 201 Tl SPECT scans to assess residual tumour after surgery and then to monitor response to treatment, with a follow-up time of 18 months. Measures of SUV max were made following quantitative processing of the data and using a threshold grown volume of interest around the tumour. Phantom studies resulted in the calculation of concentration values consistently within 4% of true values. No continuous relation was found between SUV max (post-resection) and patient survival. Choosing an SUV max cut-off of 1.5 demonstrated a difference in survival between the 2 groups of patients after surgery. Patients with an SUV max 51.5 had a 70% survival rate over the first 10 months, compared with a 47% survival rate for those with SUV max 41.5. This difference did not achieve significance, most likely due to the small study numbers. By 18 months follow-up this difference had reduced, with corresponding survival rates of 40% and 27%, respectively. Although this study involves only a small cohort, it has succeeded in demonstrating the possibility of an SUV measure for SPECT to help monitor response to treatment of brain tumours and predict survival.
Novelties and New Potentials in the Clinical Application of SPECT/CT Imaging
Journal of Nuclear Medicine & Radiation Therapy, 2016
The application of hybrid devices that is fused technologies is getting more and more important in the field of imaging diagnostics. The greatest advantage of this method is the combined use of several modalities, which can provide data about the morphological, functional and possibly molecular changes in different diseases simultaneously. In this paper the potentials, advantages and applicabilities of SPECT/CT (single photon emission computer tomograph/computer tomograph) are summarized mainly in oncological diseases but in other diseases as well. Multimodality devices detecting functional and morphological abnormalities simultaneously increase the specificity and diagnostic accuracy of nuclear medicine methods and therefore the effectiveness of therapy too.