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Radiolabeled Nanoparticles for Cancer Diagnosis
Published in D. Sakthi Kumar, Aswathy Ravindran Girija, Bionanotechnology in Cancer, 2023
R. G. Aswathy, D. Sakthi Kumar
Imaging with SPECT is based on the radioactive decay of a nuclide with emission of a γ photon where the energy is depended on the nature of the nuclide. The radioisotopes for SPECT imaging emit gamma rays with the energy ranging between ~25–250 keV. The emitted photons are detected after passing through a single or a set of collimated radiation detectors. The camera rotates around the animal’s or patient’s body and detects the areas of emission (Figure 3.2). The projection data acquired in SPECT is from different angles around the animal/patient. The detectors used in SPECT are mostly based on a single or multiple sodium iodide NaI (TI) scintillation detectors. SPECT scan acquires multiple 2D images/projections from several angles. The computer algorithm then develops tomographic reconstruction of the 2D projections thereby generating 3D image [2–4].
Theory of Tomographic Reconstruction
Published in Bhagwat D. Ahluwalia, Tomographic Methods in Nuclear Medicine: Physical Principles, Instruments, and Clinical Applications, 2020
Tomographic reconstruction techniques have been employed in a variety of medical applications. Some of the original references are in X-ray CT (computed tomography) scanning,1-3 MRI (magnetic resonance imaging) (NMR),4, 5 impedance imaging,6 ultrasound,7 and nuclear medicine for both single photon emission computed tomography (SPECT)8-11 and positron emission tomography (PET).12, 13 An even greater range of applications has been found in nonmedical areas ranging from astronomy14 to (and in particular) molecular biology.15–17 The basic mathematical methods of reconstruction techniques have tended to be rediscovered over and over again by workers in rather specific areas, unaware of the work of others in different areas. Three useful general review papers in the area of radiology/nuclear medicine are References 18 to 20 which provide a short survey of some of these techniques. An attempt at a general approach to tomographic reconstruction is presented here, followed by a brief discussion of some of the special problems in nuclear medicine, specifically attenuation and scatter correction.
Image Formation in Spectral Computed Tomography
Published in Katsuyuki Taguchi, Ira Blevis, Krzysztof Iniewski, Spectral, Photon Counting Computed Tomography, 2020
Simon Rit, Cyril Mory, Peter B. Noël
Conventional CT scanners acquire a single sinogram, mixing all photons regardless of their energy. Reconstruction algorithms for single-energy CT either neglect the energy dependency of the incident beam or use corrections for multi-energy effects known as beam hardening [8], for example by assuming that a single material composes the object in the field-of-view [7]. Spectral CT scanners employ a variety of strategies to acquire multiple sinograms representative of different energy segments of the incoming spectra [38]. The purpose of this chapter is to present specific algorithmic solutions required to utilize this additional energy dimension in combination with conventional and advanced tomographic reconstruction algorithms.
Initial UK series of endoscopic suturectomy with postoperative helmeting for craniosynostosis: early report of perioperative experience
Published in British Journal of Neurosurgery, 2023
Jonathan Halim, Adikarige Silva, Curtis Budden, David J. Dunaway, N. U. Owase Jeelani, Juling Ong, Greg James
All children referred with craniosynostosis were assessed in multidisciplinary fashion by the craniofacial team consisting of craniofacial plastic and neurosurgeons. The diagnosis was made based on clinical examination and radiographic imaging such as plain film radiograph or three-dimensional computed tomographic reconstruction, where needed. We have previously published evidence that radiological investigations do not aid diagnosis or management in ‘classical’ single suture synostosis presentations.15 Treatment options, including non-surgical surveillance, and their associated risks and benefits were discussed with the parents once the diagnosis was established.