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Use of Microcomputed Tomography and Image Processing Tools in Medicinal and Aromatic Plants
Published in Amit Baran Sharangi, K. V. Peter, Medicinal Plants, 2023
Yogini S. Jaiswal, Yanling Xue, Tiqiao Xiao, Leonard L. Williams
Tomography involves imaging of samples, where the images are created from the projections of the samples. The projections are made at a specified angle, and these projections are integrals of images created in a direction at the selected angle (Kak, Slaney, and Wang, 2002). In other words, the illumination of objects at a specific angle causes the generation of transmission energies. These transmission energies are recorded as diffracted projections, which are used for image construction. The recorded two-dimensional (2D) X-ray images are reconstructed to 3D images by use of various commercially available software (Goerne and Rajiah, 2018; Hampel, 2015).
Outpatient Assessment
Published in R James A England, Eamon Shamil, Rajeev Mathew, Manohar Bance, Pavol Surda, Jemy Jose, Omar Hilmi, Adam J Donne, Scott-Brown's Essential Otorhinolaryngology, 2022
Martyn L. Barnes, Paul S. White
Any nasal masses should be evaluated for colour, consistency, vascularity and origin. In the absence of unusual appearance, bilateral nasal polyps may not need be biopsied. Sinonasal tumours and unusual polyps should be imaged prior to biopsy. In-office biopsy can be considered but the possibility of a vascular nature (e.g. juvenile angiofibroma) or meningo(encephalo)coele must be excluded. In such cases, a computed tomography with contrast or magnetic resonance imaging scan may prevent significant complications.
Principles behind Computed Tomography (CT)
Published in Michael Ljungberg, Handbook of Nuclear Medicine and Molecular Imaging for Physicists, 2022
Mikael Gunnarsson, Kristina Ydström
The tomographic scan is usually performed as an axial- or helical-scan. An axial CT scan involves an acquisition of transmission profiles with a rotating X-ray tube and a static table. A complete axial CT examination generally involves subsequent axial acquisitions in order to cover a clinically relevant volume. The table translation is equal to the slice thickness, so that subsequent axial acquisitions can be reconstructed as contiguous axial images.
Laboratory biomarkers in the diagnosis and follow-up of treatment of allergic bronchopulmonary aspergillosis in cystic fibrosis
Published in Critical Reviews in Clinical Laboratory Sciences, 2023
Sophie Steels, Marijke Proesmans, Xavier Bossuyt, Lieven Dupont, Glynis Frans
In a classic case of ABPA, radiological investigations show the presence of new or increased bronchiectasis and mucus impaction (not specific to ABPA). Other common features are the “finger-in-glove,” tramline shadows, and tooth paste shadows [5,41]. High-resolution computed tomography of the chest is preferable to chest radiograph because of better visualization of bronchiectasis distribution [5,41]. Central bronchiectasis, an arbitrary classification in which bronchiectasis is confined to the medial two-thirds or medial half of the lung, is believed to be characteristic of ABPA. This should be considered a complication of ABPA rather than a diagnostic criterion as the presence of central bronchiectasis has a sensitivity of only 37% in diagnosing ABPA [5,42]. In addition, central bronchiectasis extended to the periphery in almost one-third of the cases described in the literature [5,43]. High-attenuation mucus, however, is a pathognomonic finding and helps to distinguish ABPA from other causes of bronchiectasis [5,44]. Nevertheless, the benefits of performing repeated high-resolution computed tomography scans should be judged against the risks of cumulative radiation exposure, especially in children. Magnetic resonance imaging offers a non-invasive imaging alternative for diagnosing ABPA without using contrast fluids or radiation. It describes mucoid impactions with T1 hyper-intensity and T2 hypo-intensity, also called inverted mucoid impaction signal sign. This sign was specific [100%, confidence interval (CI): 96–100%, n = 18] for the diagnosis of CF-ABPA [45].
Digital healthcare technologies: Modern tools to transform prosthetic care
Published in Expert Review of Medical Devices, 2021
Isaac A Cabrera, Trinity C. Pike, Joanna M. McKittrick, Marc A. Meyers, Ramesh R. Rao, Albert Y. Lin
Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) have been implemented extensively throughout the medical field. These imaging technologies benefit prosthetic design because they capture both internal and external features of residual limbs [16]. Visualizing the relative positions of bones and soft tissues can help clinicians predict the pressure distribution on a residual limb. They can then use this information to tailor the socket design for each patient, including the desired mechanical properties of the socket wall [16–18]. Both procedures require the patient to remain still (to minimize deformation) while they collect images at incremental distances across the limb. A 3D model is generated by stitching together the cross-sectional data for each surface area into a point cloud [19].
CRISPR-based biosensing systems: a way to rapidly diagnose COVID-19
Published in Critical Reviews in Clinical Laboratory Sciences, 2021
Majid Vatankhah, Amir Azizi, Anahita Sanajouyan Langeroudi, Sajad Ataei Azimi, Imaneh Khorsand, Mohammad Amin Kerachian, Jamshid Motaei
Rapid detection of SARS-CoV-2 at low cost and high sensitivity and specificity in many people is important for control of the COVID-19 pandemic. Diagnosis of COVID-19 is based on precise laboratory tests on samples that include sputum, secretions of the lower respiratory tract, nasopharyngeal swab, oropharyngeal swab, blood, feces and urine [13,14]. The diagnostic confirmation test currently performed for SARS-CoV-2 is reverse transcription polymerase chain reaction (RT-PCR). For all suspected patients, a computerized tomography (CT) scan is recommended. Most patients suffer from pneumonia, which is characterized by bilateral patchy shadowing and ground-glass opacities on the chest CT examination [15]. Several studies have shown that chest CT is more sensitive than RT-PCR for diagnosis of COVID-19 [16–18]. However, patients with positive RT-PCR may have normal chest CT at the onset of symptoms [16,19–21].