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This post-hoc analysis of the SABINA III study evaluated the association of short-acting β2-agonist (SABA) prescriptions and self-reported over-the-counter (OTC) SABA purchase in the previous 12 months with asthma-related outcomes using multivariable regression models in 4556 patients (mean age, 48.9 years). Of the 2810 patients prescribed ≥3 SABA canisters, 776 (27.6%) also purchased ≥1 SABA OTC. This subset of 776 patients reported the highest disease burden; 73.2% had ≥1 severe exacerbation and 55.7% had uncontrolled asthma. Asthma-related outcomes worsened with any SABA OTC purchase, regardless of SABA prescriptions; disease burden was the highest in patients with ≥3 SABA prescriptions and ≥1 SABA OTC purchase vs 1–2 SABA prescriptions only (86% lower odds of having at least partly controlled asthma and 124% increased incidence of severe asthma (both P < 0.001). These findings emphasize the need to implement policy changes to restrict SABA purchase without prescriptions and ensure access to affordable asthma care. [ABSTRACT FROM AUTHOR]

Background: Gamma camera imaging, including single photon emission computed tomography (SPECT), is crucial for research, diagnostics, and radionuclide therapy. Gamma cameras are predominantly based on arrays of photon multipliers tubes (PMTs) that read out NaI(Tl) scintillation crystals. In this way, standard gamma cameras can localize ɣ‐rays with energies typically ranging from 30 to 360 keV. In the last decade, there has been an increasing interest towards gamma imaging outside this conventional clinical energy range, for example, for theragnostic applications and preclinical multi‐isotope positron emission tomography (PET) and PET‐SPECT. However, standard gamma cameras are typically equipped with 9.5 mm thick NaI(Tl) crystals which can result in limited sensitivity for these higher energies. Purpose: Here we investigate to what extent thicker scintillators can improve the photopeak sensitivity for higher energy isotopes while attempting to maintain spatial resolution. Methods: Using Monte Carlo simulations, we analyzed multiple PMT‐based configurations of gamma detectors with monolithic NaI (Tl) crystals of 20 and 40 mm thickness. Optimized light guide thickness together with 2‐inch round, 3‐inch round, 60 × 60 mm2 square, and 76 × 76 mm2 square PMTs were tested. For each setup, we assessed photopeak sensitivity, energy resolution, spatial, and depth‐of‐interaction (DoI) resolution for conventional (140 keV) and high (511 keV) energy ɣ using a maximum‐likelihood algorithm. These metrics were compared to those of a "standard" 9.5 mm‐thick crystal detector with 3‐inch round PMTs. Results: Estimated photopeak sensitivities for 511 keV were 27% and 53% for 20 and 40 mm thick scintillators, which is respectively, 2.2 and 4.4 times higher than for 9.5 mm thickness. In most cases, energy resolution benefits from using square PMTs instead of round ones, regardless of their size. Lateral and DoI spatial resolution are best for smaller PMTs (2‐inch round and 60 × 60 mm2 square) which outperform the more cost‐effective larger PMT setups (3‐inch round and 76 × 76 mm2 square), while PMT layout and shape have negligible (< 10%) effect on resolution. Best spatial resolution was obtained with 60 × 60 mm2 PMTs; for 140 keV, lateral resolution was 3.5 mm irrespective of scintillator thickness, improving to 2.8 and 2.9 mm for 511 keV with 20 and 40 mm thick crystals, respectively. Using the 3‐inch round PMTs, lateral resolutions of 4.5 and 3.9 mm for 140 keV and of 3.5 and 3.7 mm for 511 keV were obtained with 20 and 40 mm thick crystals respectively, indicating a moderate performance degradation compared to the 3.5 and 2.9 mm resolution obtained by the standard detector for 140 and 511 keV. Additionally, DoI resolution for 511 keV was 7.0 and 5.6 mm with 20 and 40 mm crystals using 60 × 60 mm2 square PMTs, while with 3‐inch round PMTs 12.1 and 5.9 mm were obtained. Conclusion: Depending on PMT size and shape, the use of thicker scintillator crystals can substantially improve detector sensitivity at high gamma energies, while spatial resolution is slightly improved or mildly degraded compared to standard crystals. [ABSTRACT FROM AUTHOR]

Objective: To assess prescription patterns for short-acting β2 agonists (SABAs) and other asthma medications in asthma patients treated by specialists and participating in the SABA use IN Asthma (SABINA)studyin Brazil. Methods: This was an observational, cross-sectional study conducted at five sites in different regions of Brazil. The primary endpoints were to record SABA prescriptions and obtain data on over-the-counter (OTC) SABA purchases at the pharmacy. Results: Data on 218 asthma patients were analyzed. Of those 218 patients, 80.3% were prescribed SABAs in addition to their maintenance therapy, with a mean of 11.2 SABA canisters in the previous 12 months. Of those patients, 71.4% were prescribed ≥ 3 canisters and 42.2% were prescribed ≥ 10 canisters. None of the patients were prescribed SABA monotherapy. A total of 14.2% of the patients reported purchasing SABAs OTC at a pharmacy without a prescription. Of those, 48.4% purchased ≥ 3 SABA canisters. A fixed-dose combination of an inhaled corticosteroid and a long-acting β2 agonist was prescribed to 95.0% of the patients. In the year before the study visit, 45.0% of the patients received at least one course of oral corticosteroid burst treatment. Asthma was well controlled in 43.1% of the patients, partly controlled in 34.9%, and uncontrolled in 22.0%. Patients reported a mean of 1.1 severe asthma exacerbations, with 49.1% experiencing 1 or more severe exacerbations. Conclusions: Overprescription and OTC purchases of SABAs are common in Brazil, possibly leading to the need for courses of oral corticosteroids. The health care community should collaborate to implement evidence-based recommendations and promote health education to improve asthma management in Brazil. [ABSTRACT FROM AUTHOR]

Objective: To study the impact of premenopausal risk‐reducing salpingo‐oophorectomy (RRSO), compared with postmenopausal RRSO, on urinary incontinence (UI) ≥10 years later. Design: Cross‐sectional study, nested in a nationwide cohort. Setting: Multicentre in the Netherlands. Population: 750 women (68% BRCA1/2 pathogenic variant carriers) who underwent either premenopausal RRSO (≤45 years, n = 496) or postmenopausal RRSO (≥54 years, n = 254). All participants were ≥55 years at the time of the study. Methods: Urinary incontinence was assessed by the urinary distress inventory‐6 (UDI‐6); a score ≥33.3 indicated symptomatic UI. The incontinence impact questionnaire short form (IIQ‐SF) was used to assess the impact on women's health‐related quality of life (HR‐QoL). Differences between groups were analysed using regression analyses adjusting for current age and other confounders. Main outcome measures: Differences in UDI‐6 scores and IIQ‐SF scores between women with a premenopausal and a postmenopausal RRSO. Results: Women in the premenopausal RRSO group had slightly higher UDI‐6 scores compared with women in the postmenopausal RRSO group (P = 0.053), and their risk of symptomatic UI was non‐significantly increased (odds ratio [OR] 2.1, 95% confidence interval [95% CI] 0.93–4.78). A premenopausal RRSO was associated with a higher risk of stress UI (OR 3.5, 95% CI 1.2–10.0) but not with urge UI. The proportions of women with a significant impact of UI on HR‐QoL were similar in the premenopausal and postmenopausal RRSO groups (10.4% and 13.0%, respectively; P = 0.46). Conclusions: More than 15 years after premenopausal RRSO, there were no significant differences in overall symptomatic UI between women with a premenopausal and those with a postmenopausal RRSO. [ABSTRACT FROM AUTHOR]

Objective: Short-acting β2-agonist (SABA) overuse is associated with poor asthma outcomes; however, the extent of SABA use in Thailand is largely unknown. As part of the SABA use IN Asthma (SABINA) III study, we describe asthma treatment patterns, including SABA prescriptions, in patients treated by specialists in Thailand. Methods: In this observational, cross-sectional study, patients (aged ≥12 years) with an asthma diagnosis were recruited by specialists from three Thai tertiary care centers using purposive sampling. Patients were classified by investigator-defined asthma severity (per 2017 Global Initiative for Asthma [GINA] recommendations). Data on sociodemographics, disease characteristics, and asthma treatment prescriptions were collected from existing medical records by healthcare providers and transcribed onto electronic case report forms. Analyses were descriptive. Results: All 385 analyzed patients (mean age: 57.6 years; 69.6% female) were treated by specialists. Almost all (91.2%) patients were classified with moderate-to-severe asthma (GINA treatment steps 3-5), 69.1% were overweight/obese, and 99.7% reported partially/fully reimbursed healthcare. Asthma was partly controlled/uncontrolled in 24.2% of patients; 23.1% experienced ≥1 severe asthma exacerbation in the preceding 12 months. Overall, SABAs were over-prescribed (≥3 canisters/year) in 28.3% of patients. Inhaled corticosteroids (ICS), ICS/ long-acting β2-agonists, oral corticosteroid (OCS) burst treatment, and long-term OCS were prescribed to 7.0, 93.2, 19.2, and 6.2% of patients, respectively. Additionally, 4.2% of patients reported purchasing SABA over the counter. Conclusions: Despite receiving specialist treatment, 28.3% of patients were over-prescribed to SABA in the previous 12 months, highlighting a public health concern and the need to align clinical practices with current evidence-based recommendations. [ABSTRACT FROM AUTHOR]

Introduction: SABINA III assessed short-acting β2-agonist (SABA) prescription patterns and their association with asthma-related outcomes globally. Herein, we examined SABA prescription and clinical outcomes in the Malaysian cohort of SABINA III. Methods: In this observational, cross-sectional study, patients (≥12 years) were recruited between July and December 2019 from 15 primary and specialty care centres in Malaysia. Prescribed asthma treatments and severe exacerbation history within 12 months prior and asthma symptom control during the study visit were evaluated. Associations of SABA prescription with asthma control and severe exacerbation were analysed using multivariable regression models. Results: Seven hundred thirty-one patients (primary care, n=265 [36.3%]; specialty care, n=466 [63.7%]) were evaluated. The prevalence of SABA over-prescription (≥3 SABA prescriptions/year) was 47.4% (primary care, 47.1%; specialty care, 47.6%), 51.8% and 44.5% among all patients and patients with mild and moderate-to-severe asthma, respectively. Altogether 9.0% (n=66) purchased SABA without a prescription; among them, 43.9% (n=29) purchased ≥3 inhalers. The mean (standard deviation) number of severe asthma exacerbations was 1.38 (2.76), and 19.7% (n=144) and 25.7% (n=188) had uncontrolled and partly controlled symptoms, respectively. Prescriptions of ≥3 SABA inhalers (vs 1–2) were associated with lower odds of at least partly controlled asthma (odds ratio=0.42; 95% confidence interval [CI]=0.27–0.67) and higher odds of having severe exacerbation(s) (odds ratio=2.04; 95% CI=1.44–2.89). Conclusion: The prevalence of SABA over-prescription in Malaysia is high, regardless of the prescriber type, emphasising the need for healthcare providers and policymakers to adopt latest evidence-based recommendations to address this public health concern. [ABSTRACT FROM AUTHOR]

Objective: To examine the effect of a premenopausal risk‐reducing salpingo‐oophorectomy (RRSO) in women at increased risk of ovarian cancer on objective and subjective cognition at least 10 years after RRSO. Design: A cross‐sectional study with prospective follow‐up, nested in a nationwide cohort. Setting: Multicentre in the Netherlands. Population or Sample: 641 women (66% BRCA1/2 pathogenic variant carriers) who underwent either a premenopausal RRSO ≤ age 45 (n = 436) or a postmenopausal RRSO ≥ age 54 (n = 205). All participants were older than 55 years at recruitment. Methods: Participants completed an online cognitive test battery and a questionnaire on subjective cognition. We used multivariable regression analyses, adjusting for age, education, breast cancer, hormone replacement therapy, cardiovascular risk factors and depression. Main Outcome Measures: The influence of RRSO on objective and subjective cognition of women with a premenopausal RRSO compared with women with a postmenopausal RRSO. Results: After adjustment, women with a premenopausal RRSO (mean time since RRSO 18.2 years) performed similarly on objective cognitive tests compared with women with a postmenopausal RRSO (mean time since RRSO 11.9 years). However, they more frequently reported problems with reasoning (odds ratio [OR] 1.8, 95% confidence interval [95% CI] 1.1–3.1) and multitasking (OR 1.9, 95% CI 1.1–3.4) than women with a postmenopausal RRSO. This difference between groups disappeared in an analysis restricted to women of comparable ages (60–70 years). Conclusions: Reassuringly, approximately 18 years after RRSO, we found no association between premenopausal RRSO and objective cognition. [ABSTRACT FROM AUTHOR]

Data on severe asthma phenotypes in Latin America are lacking. The PREPARE study describes the prevalence of certain determinants of severe asthma among patients in 5 Latin American countries with blood eosinophil counts (BEC) ≥300 cells/mm3 and serum immunoglobulin E (IgE) concentrations >100 IU/mL. In this cross-sectional study, information on demographics, disease characteristics, and asthma treatments were extracted from the existing medical records of patients aged ≥12 years attending centers specialized in severe asthma management. Medical record data were transcribed onto electronic case report forms. Blood eosinophil counts and IgE concentrations were assayed from specimens obtained at study visit. Data were analyzed with descriptive statistics. Data from 461 patients with severe asthma (mean age, 50.5 years) were analyzed. Most patients were female (73%), had a body mass index of ≥25 kg/m2 (77%), and received full healthcare reimbursement (63%). In the previous 12 months, 52% of patients experienced ≥1 severe exacerbation and 44% received oral corticosteroid burst therapy. Blood eosinophil counts ≥300 cells/mm3 and ≥150 cells/mm3 were reported in 44% and 76% of patients, respectively. In 58% of patients, serum IgE concentrations exceeded 100 IU/mL. Uncontrolled asthma was documented in 50% (n = 230) of patients. The PREPARE study provides useful insights about the prevalence of eosinophilic and atopic phenotypes in patients with severe asthma in Latin America, thereby paving the way for a more personalized approach to managing severe asthma. Notwithstanding the treatment at specialized medical centers, disease burden remained high in this study population. [ABSTRACT FROM AUTHOR]

Short-acting β2-agonist (SABA) over-reliance is associated with poor asthma outcomes. As part of the SABA Use IN Asthma (SABINA) III study, we assessed SABA prescriptions and clinical outcomes in patients from six Latin American countries. In this cross-sectional study, data on disease characteristics/asthma treatments were collected using electronic case report forms. Patients (aged ≥12 years) were classified by investigator-defined asthma severity (guided by the 2017 Global Initiative for Asthma) and practice type (primary/specialist care). Multivariable regression models analyzed the associations between SABA prescriptions and clinical outcomes. Data from 1096 patients (mean age, 52.0 years) were analyzed. Most patients were female (70%), had moderate-to-severe asthma (79.4%), and were treated by specialists (87.6%). Asthma was partly controlled/uncontrolled in 61.5% of patients; 47.4% experienced ≥1 severe exacerbation in the previous 12 months. Overall, 39.8% of patients were prescribed ≥3 SABA canisters in the preceding 12 months (considered over-prescription). SABA canisters were purchased over the counter (OTC) by 17.2% of patients, of whom 38.8% purchased ≥3 canisters in the 12 months prior. Of patients who purchased SABA OTC, 73.5% were prescribed ≥3 SABA canisters. Higher SABA prescriptions (vs. 1 − 2 canisters) were associated with an increased incidence rate of severe exacerbations (ranging from 1.31 to 3.08) and lower odds ratios of having at least partly controlled asthma (ranging from 0.63 to 0.15). SABA over-prescription was common in Latin America, highlighting the need for urgent collaboration between healthcare providers and policymakers to align clinical practices with the latest evidence-based recommendations to address this public health concern. [ABSTRACT FROM AUTHOR]

Implant infections caused by Staphylococcus aureus are difficult to treat due to biofilm formation, which complicates surgical and antibiotic treatment. We introduce an alternative approach using monoclonal antibodies (mAbs) targeting S. aureus and provide evidence of the specificity and biodistribution of S.-aureus-targeting antibodies in a mouse implant infection model. The monoclonal antibody 4497-IgG1 targeting wall teichoic acid in S. aureus was labeled with indium-111 using CHX-A"-DTPA as a chelator. Single Photon Emission Computed Tomography/computed tomographyscans were performed at 24, 72 and 120 h after administration of the 111In-4497 mAb in Balb/cAnNCrl mice with a subcutaneous implant that was pre-colonized with S. aureus biofilm. The biodistribution of this labelled antibody over various organs was visualized and quantified using SPECT/CT imaging, and was compared to the uptake at the target tissue with the implanted infection. Uptake of the 111In-4497 mAbs at the infected implant gradually increased from 8.34 %ID/cm3 at 24 h to 9.22 %ID/cm3 at 120 h. Uptake at the heart/blood pool decreased over time from 11.60 to 7.58 %ID/cm3, whereas the uptake in the other organs decreased from 7.26 to less than 4.66 %ID/cm3 at 120 h. The effective half-life of 111In-4497 mAbs was determined to be 59 h. In conclusion, 111In-4497 mAbs were found to specifically detect S. aureus and its biofilm with excellent and prolonged accumulation at the site of the colonized implant. Therefore, it has the potential to serve as a drug delivery system for the diagnostic and bactericidal treatment of biofilm. [ABSTRACT FROM AUTHOR]

The extent of short-acting β2-agonist (SABA) overuse in Africa remains poorly documented. As part of the SABA use IN Asthma (SABINA) III study, we assessed SABA prescriptions/clinical outcomes in 3 African countries. Data on disease characteristics/asthma treatments were collected from patients (≥12 years) using electronic case report forms. Patients were classified by investigator-defined asthma severity (guided by the 2017 Global Initiative for Asthma) and practice type (primary/specialist care). Multivariable regression models analyzed associations between SABA prescriptions and outcomes. Data from 1778 patients (mean age, 43.7 years) were analyzed. Most patients were female (62.4%) and had moderate-to-severe asthma (63.3%), with 57.1 and 42.9% of patients treated in specialist and primary care, respectively. Asthma was partly controlled/uncontrolled in 66.2% of patients, with 57.9% experiencing ≥1 severe exacerbation in the previous 12 months. Overall, 46.5% of patients were prescribed ≥3 SABA canisters in the preceding 12 months (over-prescription); 26.2% were prescribed ≥10 canisters. SABAs were purchased over-the-counter by 32.6% of patients, of whom 79.3% had received SABA prescriptions; 71.9% and 40.1% for ≥3 and ≥10 canisters, respectively. Higher SABA prescriptions (vs. 1–2 canisters) were associated with increased incidence rate of severe exacerbations and lower odds of having at least partly controlled asthma (except 3–5 canisters). Findings from this African cohort of the SABINA III study indicate that SABA over-prescription and SABA over-the-counter purchase are common and associated with poor asthma-related outcomes. This highlights the need for healthcare providers/policymakers to align clinical practices with the latest treatment recommendations. [ABSTRACT FROM AUTHOR]

For multipinhole single-photon emission computed tomography (SPECT), iterative reconstruction algorithms are preferred over analytical methods, because of the often complex multipinhole geometries and the ability of iterative algorithms to compensate for effects like spatially variant sensitivity and resolution. Ideally, such compensation methods are based on accurate knowledge of the position-dependent point spread functions (PSFs) specifying the response of the detectors to a point source at every position in the instrument. This paper describes a method for model-based generation of complete PSF lookup tables from a limited number of point-source measurements for stationary SPECT systems and its application to a submillimeter resolution stationary small-animal SPECT system containing 75 pinholes (U-SPECT-I). The method is based on the generalization over the entire object to be reconstructed, of a small number of properties of point-source responses which are obtained at a limited number of measurement positions. The full shape of measured point-source responses can almost be preserved in newly created PSF tables. We show that these PSFs can be used to obtain high-resolution SPECT reconstructions: the reconstructed resolutions judged by rod visibility in a micro-Derenzo phantom are 0.45 mm with 0.6-mm pinholes and below 0.35 mm with 0.3-mm pinholes. In addition, we show that different approximations, such as truncating the PSF kernel, with significant reduction of reconstruction time, can still lead to acceptable reconstructions. Index Terms--Calibration, pinhole, reconstruction, single-photon emission computed tomography (SPECT).

Channel-edge pinhole designs have been proposed in order to reduce the penetration of gamma rays through the edge of the pinhole aperture. A characterization of penetration and scatter in the pinhole aperture metal can be used in the design of small animal SPECT collimators or for model based corrections during micro-SPECT image reconstruction. In this study the penetration and scatter contributions of micropinholes were compared for Tc-99m, 1-123, and 1-125 for knife-edges and channel-edges. To this end, Geant 4 Monte Carlo simulations of 0.3 mm and 0.5 mm diameter apertures with acceptance angles ranging from 20 to 60 degrees were performed. At perpendicular incidence of the photons, channel pinholes had lower penetration and scatter fractions than did knife-edge pinholes. This advantage disappeared at higher angles of incidence. In addition, the total sensitivity decreased substantially with increasing channel height. Planar projection images of a grid of spheres showed that channel-edge pinholes resulted in a slightly higher spatial resolution than knife-edge pinholes with an equal diameter, when combined with a high-resolution detector. However, the channel-edge pinhole's sensitivity and Contrast Inverse Coefficient of Variation were lower than the knife edge pinhole's at the edges of the detector. We conclude that channel pinholes can result in lower imaging performance when used with non-perpendicular incidence photons because of loss of sensitivity. Index Terms--Monte Carlo simulation, penetration, pinhole geometry, pinhole SPECT, scattering.

Cupping and streak artifacts caused by the detection of scattered photons may severely degrade the quantitative accuracy of cone-beam X-ray computed tomography (CT) images. In order to overcome this problem, we propose and validate the following iterative scatter artifact reduction scheme. First, an initial image is reconstructed from the scatter-contaminated projections. Next, the scatter component of the projections is estimated from the initial reconstruction by a Monte Carlo (MC) simulation. The estimate obtained is then utilized during the reconstruction of a scatter-corrected image. The last two steps are repeated until an adequate correction is obtained. The estimation of the noise-free scatter projections in this scheme is accelerated in the following way: first, a rapid (i.e., based on a low number of simulated photon tracks) MC simulation is executed. The noisy result of this simulation is de-noised by a three-dimensional fitting of Gaussian basis functions. We demonstrate that, compared to plain MC, this method shortens the required simulation time by three to four orders of magnitude. Using simulated projections of a small animal phantom, we show that one cycle of the scatter correction scheme is sufficient to produce reconstructed images that barely differ from the reconstructions of scatter-free projections. The reconstructions of data acquired with a charge-coupled device based micro-CT scanner demonstrate a nearly complete removal of the scatter-induced cupping artifact. Quantitative errors in a water phantom are reduced from around 12% for reconstructions without the scatter correction to 1% after the proposed scatter correction has been applied. In conclusion, a general, accurate, and efficient scatter correction algorithm is developed that requires no mechanical modifications of the scanning equipment and results in only a moderate increase in the total reconstruction time. Index Terms--Artifact removal, computed tomography, cone beam, image reconstruction, medical imaging, Monte Carlo simulation, scatter.

Quantitative accuracy of single-photon-emission computed tomography (SPECT) images is highly dependent on the photon scatter model used for image reconstruction. Monte Carlo simulation (MCS) is the most general tool for accurate modeling and correction of scatter, but calculations are notoriously slow. Recently, we proposed an efficient strategy for fully three-dimensional (3-D) statistical reconstruction using highly accelerated MCS as a forward projector. We use convolution forced detection (CFD) which accelerates convergence of reprojection by about two orders of magnitude. Here, we investigate how many photon histories during CFD-based MCS need to be calculated to: i) ensure that the noise in the reconstructed image does not increase markedly because of the stochastic nature of MCS reprojections; and ii) to determine the reconstruction time needed. To this end, phantom studies representing Tc-99m cardiac perfusion SPECT, were carried out. We generated reconstructions with different numbers of photon histories during MCS forward projection. Images and profiles were compared for reconstructions with a different number of photon tracks, for reconstructions from different noise realizations using a repeat measurement and for reconstructions with different random seeds for MCS reprojection. We found that [10.sup.5] photon histories per subset is sufficient to produce accurate images; more photons do not show visible improvement. This amount of photons corresponds to a typical reconstruction time below 5 min for a [64.sup.3] volume image on a dual-cpu PC (2.66 GHz), which is sufficiently short to apply such highly accurate reconstruction in clinical routine. Index Terms--Cardiac imaging, image reconstruction, Monte Carlo simulation, scatter, single photon emission computed tomography.

We have developed a compact ultra-high-resolution gamma camera (UGC), based on an electron-multiplying charge-coupled device (EMCCD) coupled to a columnar CsI(Tl) scintillator. The EMCCD is suitable for photon-counting gamma-camera imaging, since it has an extremely low readout noise, even at high frame rates ( Index Terms--Charge-coupled device (CCD), digital signal processor (DSP), electron-multiplying charge-coupled device (EMCCD), gamma camera, molecular imaging, photon-counting, readout electronics, single photon emission computed tomography (SPECT).