The History of Nuclear Medicine
Michael Ljungberg in Handbook of Nuclear Medicine and Molecular Imaging for Physicists, 2022
A more significant step in the development of instrumentation in nuclear medicine was the development of the scintillation camera in 1958 by Hal O. Anger. He replaced the film with an array of PMTs mounted on a large single NaI(Tl) crystal. The origin of the registered gamma ray – that is, the scintillation in the crystal – was detected by weighting together the signals from the PMTs. This apparatus, also known as the Anger camera or gamma camera, revolutionized the field of nuclear medicine and was a real breakthrough for imaging, thereby enabling dynamic in vivo studies possible. The first Anger camera was installed at Ohio State University in 1962 by Nuclear Chicago and in subsequent years at many hospitals in the United States and Europe. The technique is still the basis used in today’s single photon emission computed tomography (SPECT) cameras, although extensive improvement has been achieved since then [3, 30].
Use of Computers in Radiotracer Studies
Lelio G. Colombetti in Principles of Radiopharmacology, 2019
Regions of interest are an essential part of a computer system designed for analysis of Anger camera images. A region of interest, abbreviated ROI, is a group of cells in the digitized image that are selected by the human user. The group of cells corresponding to a ROI is assigned a label (such as a letter or a number). The computer then prints out on the video display the number of cells selected, and the total counts in those cells. Information is also stored in the computer memory to designate the cells chosen for a particular region of interest. A region of interest may be selected by the operator using a cursor presented on the video image, along with a means to move the cursor. The cursor may be moved using a keypad, a light pen, or a joy stick. Figure 6 shows a cursor as presented on a television screen, and Figures 4, 5, and 7 show regions of interest that were set by use of a cursor. Regions of interest are essential for drawing curves of counts vs. time coming from a particular organ. A series of digitized images is stored on magnetic disk as a radiotracer moves around in the human or animal subject. A series of sequential images is called a dynamic study, or synonymously, a flow study. After the data is recorded a ROI is set over an organ of interest. The computer program then reads in the sequential images from magnetic disk and constructs a graph of the counts in the ROI vs. time.
Dictionary
Mario P. Iturralde in Dictionary and Handbook of Nuclear Medicine and Clinical Imaging, 1990
Anger camera. Type of γ ray scintillation camera, named for its inventor Hal O. Anger. A detecting system (employing a single crystal 25 to 90 cm in diameter and 0.6 to 1.25 cm thick, and 37 to 91 photodetecting circuits) that views the entire field at once and is most effective in the 100- to 300-keV energy range.
Predictors of poor cerebral collaterals and cerebrovascular reserve in patients with chronic total carotid occlusion
Published in International Journal of Neuroscience, 2019
Haytham Rizk, Mahmoud Allam, Ahmed Hegazy, Haytham Khalil, Hanan Helmy, Hebatalla Saher Hashem, Foad Abd-Allah
Baseline SPECT scans were obtained under resting conditions 30 min after IV injection of 20 mCi of 99 mTc hexamethyl-propyleneamineoxime (HMPAO).The dipyridamole SPECT scan was performed at approximately 48 h after the baseline study. Dipyridamole was administered at a dosage of 0.57 mg/kg IV over 4 min followed 3 min later by administration of 20 mCi 99 mTc-HMPAO. SPECT acquisition was performed 30 min after tracer injection according to the protocol of Te-Long and colleagues [5].Both baseline and dipyridamole SPECT scans were obtained under similar environmental conditions with the patients’ eyes opened without any acoustic, visual or motor stimulation.Patients were scanned using a rotating dual-head gamma camera (Axis, Marconi Medical Systems). The camera heads were equipped with a low-energy, all-purpose collimator. Sixty-four projections with an imaging time of 35 sec per projection were obtained. After attenuation correction, 8.8-mm thick cross-sections were reconstructed as transaxial, coronal and sagittal views by back projection and the use of a Butterworth filter in 128 × 128 matrices.
Early initiation of insulin attenuates histological and functional changes in the liver of streptozotocin-induced diabetic rats using 99mTc-sulfur colloid functional imaging
Published in Journal of Receptors and Signal Transduction, 2022
Fatma J. Al-Saeedi, Salah Kh. Al-Waheeb, Peramaiyan Rajendran, Khalid M. Khan, Moudhi Sadan
In brief, the rats were anesthetized using an intraperitoneal (i.p.) injection of ketamine:xylazine (40 mg/kg:5 mg/kg body weight). The rats were positioned face up, and an anterior view of whole body (WB) was taken using a large-field-of-view, 40 × 60 cm clinical gamma camera (Philips camera; Odyssey LX, UK) fitted with a low-energy, all-purpose, parallel-hole collimator connected to a data acquisition computer. Imaging involved two dynamic phases: vascular phase: 1 s/frame for 1 min, followed by parenchymal phase at 1 min/frame for 1 h after injection of 37 MBq of 99mTc-SC. Images were acquired in a 64 × 64 pixel matrix using a photopeak centered at 140 keV with a symmetric 20% window and zoom of 4. Regional distributions and organ/tissue uptake of 99mTc-SC tracer was determined by drawing regions of interest [32] over heart, liver, spleen and whole body (WB) (Figure 1). Ratio as the cumulative counts of the ROI’s of each organ to WB ROI was calculated. These ratios represent the percentage of radioactivity uptake compared to the WB counts for the heart, liver, and spleen for each group over 60 min.
Progress in large field-of-view interventional planar scintigraphy and SPECT imaging
Published in Expert Review of Medical Devices, 2022
Martijn M.A. Dietze, Hugo W.A.M de Jong
Several companies have introduced mobile gamma cameras to translate large field-of-view imaging to the operation room. Three examples, that are based on a conventional NaI(Tl) scintillation crystal that is coupled with photomultiplier-tubes, are the Nucline TH by Mediso Medical Imaging Systems [35], the SoloMobile by DDD Diagnostic [36], and the Cardiotom by Adolesco AB (see Figure 1b) [37–39]. These devices have the benefit that they are based on the conventional gamma camera design for which a lot of experience is already available. A disadvantage is that this conventional gamma camera is relatively bulky: this makes it somewhat less appropriate for use in the dynamic environment of the intervention room (because there is a bigger chance for collisions) and this places more demands on the supporting gantry.
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