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Imaging as an Important Tool for Diagnosis of Breast Cancer
Published in Shazia Rashid, Ankur Saxena, Sabia Rashid, Latest Advances in Diagnosis and Treatment of Women-Associated Cancers, 2022
Priyanka Mudaliar, Shafina Siddiqui, Sangeeta Ballav, Narrayan Raam Shankar, Soumya Basu, Jyotirmoi Aich
SPECT is a radiology imaging diagnostic technology which utilizes gamma rays [13]. In SPECT, 99mTc (a radiopharmaceutical) is taken up by activated mitochondria in malignant breast cells after injection. Gamma rays with an energy of around 140 keV are emitted and collected in a huge planar gamma detector underneath the compressed breast [2]. Combining SPECT with CT (computed tomography) enhances the accuracy of breast cancer diagnosis [13].
Preclinical Molecular Imaging Systems
Published in Michael Ljungberg, Handbook of Nuclear Medicine and Molecular Imaging for Physicists, 2022
In clinical SPECT imaging, the detector system is almost exclusively based on the original Anger design using a monolithic NaI:Tl crystal coupled to an array of PMTs. In preclinical SPECT a greater variety of scintillators and photodetector readouts are used in the instrumentation design. There are two basic scintillator designs used: monolithic and pixelated. Using a monolithic crystal, the position of the absorbed photon is localized by the light distribution projected on the photodetectors. How well the photodetector can localize the event depends on several factors, including how much light is produced, light dispersion, and spatial resolution of the photodetector. In contrast to a pixelated detector, the spatial sampling is continuous, which allows selection of arbitrary pixel dimensions.
Radionuclide Bone Scintigraphy
Published in Michael Ljungberg, Handbook of Nuclear Medicine and Molecular Imaging for Physicists, 2022
Kanhaiyalal Agrawal, Gopinath Gnanasegaran
Bone scans, particularly bone SPECT-CT, are very helpful in the diagnosis of benign bone diseases. The planar bone scan is highly sensitive in detecting uptake in the benign bone disease; however, the findings can be non-specific and non-contributary in most of such cases. SPECT-CT helps in localization of the uptake seen on the planar bone scan and also characterization of pathology at the uptake site. In most patients with shin splints, stress fractures, Paget’s disease, and Fibrous dysplasia, the diagnosis can be easily made on a planar bone scan based on the tracer uptake pattern. The role of SPECT-CT is complementary and, hence, can be additionally used to increase diagnostic confidence. However, in unexplained pain in the wrist, back, hip, knee, ankle, and foot, the uptake pattern is non-specific on the planar scans. SPECT-CT helps immensely in these conditions to reach an accurate diagnosis.
Ethical and Legal Considerations of Alternative Neurotherapies
Published in AJOB Neuroscience, 2021
Ashwini Nagappan, Louiza Kalokairinou, Anna Wexler
In traditional health care settings, SPECT imaging is typically used to evaluate neurological diseases, such as stroke, epilepsy, and neurodegenerative disorders (ACR 2016). The SPECT imaging procedure consists of an IV injection of radioactive material, followed by a nuclear scan of the radioactive material in the brain (Cedars Sinai 2019). There are at least a dozen clinics in the U.S. offering SPECT scans for neuropsychiatric diagnostics and evaluations, such as CereScan, PathFinder, Neuro-Luminance Inc., DrSpectScan (CereScan 2020; DrSpectScan n.d.; Neuro-Luminance Inc. 2019; PathFinder 2020), and the eight locations of the Amen Clinics (2020b). At the Amen Clinics, the cost of an initial SPECT evaluation is approximately $4,000 (A. Nagappan, personal communication, July 24, 2020). The Amen Clinics claim that SPECT is useful both in the diagnosis of recognized clinical conditions listed in the Diagnostic and Statistical Manual of Mental Disorders (DSM) such as bipolar disorder, panic disorders, and attention deficit disorder (ADD), as well as their own variations of such conditions, such as the “Ring of Fire ADD,” “Overfocused ADD,” and “Limbic ADD” (Amen Clinics 2020c). In addition, a few clinics make more general promotional statements about the use of SPECT to improve brain health (DrSpectScan n.d., Cerescan 2020.).
Brain-targeting by optimized 99mTc-olanzapine: in vivo and in silico studies
Published in International Journal of Radiation Biology, 2020
Ahmed B. Ibrahim, Hesham A. Shamsel-Din, A. Samir Hussein, M. Alaraby Salem
The technology for brain diagnosis has become an important tool in both research and clinical care. Neuroscientists use that technology to visualize brain structure and function from the level of individual molecules to the whole brain, in order to recognize and diagnose neurological disorders, and develop new strategies for treatment (Saddar et al. 2014). The study aimed at utilizing drugs that cross blood-brain barrier to develop potential radiopharmaceuticals for non-surgical imaging of the brain. The evolution of brain-imaging radiopharmaceuticals has progressed quickly in recent years. Single Photon Emission Computed Tomography (SPECT) is a commonly used nuclear imaging technique in diagnosis, evaluation of therapeutic response, selection of medical or surgical treatment, and detection of benign or malignant tissue. All these uses are highly relevant to malignant brain tumors, head injuries, cardiovascular disease, epilepsy, dementia and movement disorders (Heinz et al. 2000; Bonte and Devous 2003; Bammer et al. 2005; Brooks 2005; Dickerson and Sperling 2005; Eckert and Eidelberg 2005; Kuzniecky 2005; Lee and Newberg 2005).
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.