Imaging Facilities Research Articles

Questionnaire-based Survey on Radiation Treatment Planning using Multimodality Facilities in Radiotherapy Centres across India: A Cross-sectional Study

Introduction: India is a low-middle-income country, and there is an increase in the burden of cancer under Non Communicable Diseases (NCD) in past decades. Around 60% of cancer patients require Radiotherapy (RT), either definitive or palliative in conjunction with other modalities. Considering the present requirements in the field of RT, data has been presented about centres providing both basic and advanced RT facilities. Aim: To give an overview of current facilities available and to identify the multimodality-based planning in RT centres across India. Materials and Methods: A cross-sectional questionnairebased survey was conducted in centres having RT facilities in India, from March 2021 to April 2022. A systemic list of the current existing RT centres was taken from the Atomic Energy Regulatory Board (AERB) website. From the database list, 100 participants were selected randomly, with their contact information such as E-mail and WhatsApp. A Google survey form with a questionnaire was created for the study. The survey link forms were circulated across the RT centres in India. Results: A total of 65 centres participated in the study. The percentage of responses found to be from North India 17 (26%), South India 24 (36.9%), West India 7 (10.8%), East India 9 (13.8%) and central India 7 (10.8%) with one centre (1.5%) not disclosed. The number of government, semi-private, private and not disclosed types of hospitals participated in the survey were 19 (29.2%), 5 (7.7%), 38 (58.5%) and 3 (4.6%), respectively. The average number of functional teletherapy machines, telecobalt and linear accelerators per centre was found to be 1.24±1.33, 0.34±0.54, and 1.11±1.06, respectively. The multimodality imaging facility for RT planning was found to be 36 (55.4%) MRI and 23 (35.4%) Positron Emission Tomography-Computed Tomography (PET-CT). The median cost of Intensity Modulated Radiotherapy (IMRT), Intensity Guided Radiotherapy (IGRT), 4-Dimensional IMRT (4-D IMRT), and 4-Dimensional IGRT (4-D IGRT) in Lakhs (L) was found to be 1.20 L (0.00-3.00), 1.50 L (0.00-3.30), 1.50 L (0.00-4.00), 1.50 L (0.00-4.00), respectively. For advance PET-CT based RT planning the median cost was found to be, for IMRT treatment 1.20 L (0.00-3.50) and for IGRT treatment 1.60 L (0.00-4.00). Conclusion: There is a significant increase in radiation facilities in the recent millennium, especially in the private sector. The latest RT centres are equipped with multiple imaging modalities to accommodate the advanced RT planning features.

Distribution of Diagnostic Radiological Imaging Facilities in Public Hospitals in the Central Province of Sri Lanka

No abstract available

CCAT-prime Collaboration: Science Goals and Forecasts with Prime-Cam on the Fred Young Submillimeter Telescope

We present a detailed overview of the science goals and predictions for the Prime-Cam direct-detection camera–spectrometer being constructed by the CCAT-prime collaboration for dedicated use on the Fred Young Submillimeter Telescope (FYST). The FYST is a wide-field, 6 m aperture submillimeter telescope being built (first light in late 2023) by an international consortium of institutions led by Cornell University and sited at more than 5600 m on Cerro Chajnantor in northern Chile. Prime-Cam is one of two instruments planned for FYST and will provide unprecedented spectroscopic and broadband measurement capabilities to address important astrophysical questions ranging from Big Bang cosmology through reionization and the formation of the first galaxies to star formation within our own Milky Way. Prime-Cam on the FYST will have a mapping speed that is over 10 times greater than existing and near-term facilities for high-redshift science and broadband polarimetric imaging at frequencies above 300 GHz. We describe details of the science program enabled by this system and our preliminary survey strategies.

Kinematics of the diffuse intragroup and intracluster light in groups and clusters of galaxies in the local universe within 100 Mpc distance

Nearly all intragroup (IGL) and intracluster light (ICL) comes from stars that are not bound to any single galaxy but were formed in galaxies and later unbound from them. In this review we focus on the physical properties–phase space properties, metallicity and age distribution–of the ICL and IGL components of the groups and clusters in the local universe, within 100 Mpc distance. Kinematic–information on these very low surface brightness structures mostly comes from discrete tracers such as planetary nebulae and globular clusters, showing highly unrelaxed velocity distributions. Cosmological hydrodynamical simulations provide key predictions for the dynamical state of IGL and ICL and find that most IC stars are dissolved from galaxies that subsequently merge with the central galaxy. The increase of the measured velocity dispersion with radius in the outer halos of bright galaxies is a physical feature that makes it possible to identify IGL and ICL components. In the local groups and clusters, IGL and ICL are located in the dense regions of these structures. Their light fractions relative to the total luminosity of the satellite galaxies in a given group or cluster are between a few to ten percent, significantly lower than the average values in more evolved, more distant clusters. IGL and ICL in the Leo I and M49 groups, and the Virgo cluster core around M87, has been found to arise from mostly old (≥10 Gyr) metal-poor ([Fe/H] <-1.0) stars of low-mass progenitor galaxies. New imaging facilities such as LSST, Euclid, and the “big eyes’’ on the sky–ELT and JWST with their advanced instrumentation–promise to greatly increase our knowledge of the progenitors of the IGL and ICL stars, their ages, metal content, masses and evolution, there by increasing our understanding of this enigmatic component.

Detecting planetary mass companions near the water frost-line using JWST interferometry

ABSTRACT JWST promises to be the most versatile infrared observatory for the next two decades. The Near Infrared and Slitless Spectrograph (NIRISS) instrument, when used in the Aperture Masking Interferometry (AMI) mode, will provide an unparalleled combination of angular resolution and sensitivity compared to any existing observatory at mid-infrared wavelengths. Using simulated observations in conjunction with evolutionary models, we present the capability of this mode to image planetary mass companions around nearby stars at small orbital separations near the circumstellar water frost-line for members of the young, kinematic moving groups β Pictoris, TW Hydrae, as well as the Taurus–Auriga association. We show that for appropriately chosen stars, JWST/NIRISS operating in the AMI mode can image sub-Jupiter companions near the water frost-lines with ∼68 per cent confidence. Among these, M-type stars are the most promising. We also show that this JWST mode will improve the minimum inner working angle by as much as ∼50 per cent in most cases when compared to the survey results from the best ground-based exoplanet direct imaging facilities (e.g. VLT/SPHERE). We also discuss how the NIRISS/AMI mode will be especially powerful for the mid-infrared characterization of the numerous exoplanets expected to be revealed by Gaia. When combined with dynamical masses from Gaia, such measurements will provide a much more robust characterization of the initial entropies of these young planets, thereby placing powerful constraints on their early thermal histories.

Dense-field spray droplet size quantification of flashing boiling atomization using structured laser illumination planar imaging technique

The statistics of droplets formed by the primary jet breakup of a liquid atomization system are critical since it determines the atomization quality and resultant spray characteristics. However, quantifying the droplet statistics by applying optical diagnostic instruments is challenging because of the dense population of droplets near the nozzle exit. In a flash boiling spray, the more rapid breakup produces a higher optical dense droplet cloud, which is more challenging. Besides, the interference from the vapor phase heavily evaporated is more problematic. In this study, we incorporated an in-house developed laser-induced exciplex fluorescence (LIEF/Mie) based droplet sizing technique to quantify the near-field droplet characteristics of a single jet flash boiling spray, which can separate the liquid spray from the vapor phase to eliminate the influence of the vaporization. To mitigate the interference of multiple scattering in the dense region, a 3-phase structured laser illumination planar imaging (3p-SLIPI) facility was implemented into the measuring system to modulate the laser beam. The combination of these two unique techniques succeeded in obtaining accurate quantification of a planar droplet size distribution of this flash boiling spray. The 3p-SLIPI-LIEF/Mie measurements were validated against phase Doppler interferometry (PDI) droplet size measurement results. It is found from this study that the SLIPI-LIEF/Mie results are more accurate and more appropriate for simulation or theoretical analysis compared to LIEF/Mie results. The investigation of the flash boiling sprays under various superheat conditions was conducted using this technique. The quantitative near-field droplet size information reveals the prompt atomization mechanism of the flash boiling sprays. Comparing to the non-flash boiling sprays, the SMD is much smaller, the distribution is more uniform, and the tendency becomes more significant as the superheat degree increases. The SLIPI-LIEF/Mie results show that there is no liquid core region or sudden droplet size reduction due to flash boiling secondary micro-explosion breakups. Rather, a central dense region formed due to rapid expansion and evaporation at the exterior zones of the flash boiling spray was found.

ALZ‐NET: Using Real World Evidence to Inform the Future of Alzheimer’s Treatment and Care

AbstractBackgroundThere are over 100 therapies being tested in clinical trials for Alzheimer’s disease (AD) today. With therapies undergoing regulatory review and a growing DRUG DEVELOPMENT pipeline, the field is entering a new era of molecular‐specific therapies. A national registry represents an opportunity to evaluate the longitudinal outcomes of patients treated with any novel FDA‐approved AD therapy in real‐world settings, to inform clinical practice.MethodThe Alzheimer’s Association, the American College of Radiology, the American Society of Neuroradiology, the Department of Biostatistics, Brown University School of Public Health and the Critical Path Institute, along with other clinical research and imaging experts, are launching Alzheimer’s Network for Treatment and Diagnostics (ALZ‐NET). ALZ‐NET will build on expertise from successful registries in other therapeutic areas and the IDEAS and New IDEAS studies which demonstrated large‐scale, real‐world data collection in dementia practice is feasible for addressing critical research questions. Networks of dementia practices and imaging facilities will provide the foundation of ALZ‐NET. Data collection and sharing will be fully compliant with human participant protections, privacy and patient/provider autonomy.ResultALZ‐NET will collect longitudinal clinical and safety data for enrolled patients treated with novel FDA‐approved AD therapies and will track patient long‐term health outcomes (effectiveness and safety), associated with use in real‐world settings. ALZ‐NET aims to assess clinical course of people from a variety of backgrounds and communities, to achieve representativeness beyond the populations historically enrolled in clinical trials.Objectives of ALZ‐NET:• Develop multisite network for enrolling providers and collection of patient data.• Collect baseline and longitudinal patient data, including measures of cognition, function, and long‐term safety.• Track health outcomes and resource utilization through existing databases.• Collect and archive diagnostic and safety data and neuroimaging, genetic and fluid biomarkers.• Share deidentified data, images and biosamples with research community and other stakeholders.ConclusionALZ‐NET will establish a network of sites with an expandable platform, allowing for the collection of real‐world data from enrolled patients receiving novel FDA‐approved AD therapies. ALZ‐NET will be a resource for evidence gathering, information sharing, and education across clinical and research communities, encouraging innovative, inclusive research and supporting opportunities to improve care.

Prospects and challenges of entrepreneurship in radiography practice among radiographers in selected imaging facilities in Anambra state, Nigeria

Prospects and challenges of entrepreneurship in radiography practice among radiographers in selected imaging facilities in Anambra state, Nigeria

Neutron phase contrast imaging of PbWO4 crystals for G experiment test masses using a Talbot-Lau neutron interferometer

The use of transparent test/source masses can benefit future measurements of Newton’s gravitational constant G. Such transparent test mass materials can enable nondestructive, quantitative internal density gradient measurements using optical interferometry and allow in-situ optical metrology methods to be realized for the critical distance measurements often needed in a G apparatus. To confirm the sensitivity of such optical interferometry measurements to internal density gradients it is desirable to conduct a check with a totally independent technique. We present an upper bound on possible internal density gradients in lead tungstate (PbWO4) crystals using a Talbot-Lau neutron interferometer on the Cold Neutron Imaging Facility at NIST. We placed an upper bound on a fractional atomic density gradient in two PbWO4 test crystals of cm−1. This value is about two orders of magnitude smaller than required for G measurements. We discuss the implications of this result and of other nondestructive methods for characterization of internal density inhomogeneties which can be applied to test masses in G experiments.

Common bile duct pressure after open intraoperative instrumentation in patients with uncomplicated choledocholithiasis.

Common bile duct pressure (CBDP) after surgical exploration has not been fully detailed. The objective was to describe the changes of CBDP after open surgical exploration in patients with choledocholithiasis, considering clinical scenarios in remote locations. A before-after study was designed. Patients with choledocholithiasis who required an open cholecystectomy with exploration of bile ducts were included in the study. Open cholecystectomy was performed and perioperative T-tube CBDP was registered immediately after the procedure and weekly thereafter, with a 6 week follow-up. Control T-tube cholangiogram was performed at week 6 to exclude residual stones. Data were analyzed with T test for paired samples. Thirteen patients were included (age range, 17-69 years; 38.69 ± 17.97). Mean CBDP (cm H2O) registered were as follows: Initial = 19.5, week 1 = 16.2, week 2 = 14.3, week 3 = 13.0, week 4 = 12.1, week 5 = 11.1, and week 6 = 9.7. There were significant differences shown when comparing week 2 (p = 0.05), week 3 (p = 0.036), week 4 (p = 0.023), week 5 (p = 0.010), and week 6 (p = 0.004) with the initial value. CBDP decreases between 2nd and 3rd post-operative weeks. The use of choledochomanometry is useful in clinical scenarios with no access to imaging or interventionism facilities as in remote populations or rural locations.

Reducing Wait Times for Radiology Exams Around Holiday Periods: A Monte Carlo Simulation.

Reducing patient wait times is a key operational goal and impacts patient outcomes. The purpose of this study is to explore the effects of different radiology scheduling strategies on exam wait times before and after holiday periods at an outpatient imaging facility using computer simulation.An idealized Monte Carlo simulation of exam scheduling at an outpatient imaging facility was developed based on the actual distribution of scheduled exams at outpatient radiology sites at a tertiary care medical center. Using this simulation, we examined three scheduling strategies: (1) no scheduling modifications, (2) increase imaging capacity before or after the holiday (i.e. increase facility hours), and (3) use a novel rolling release scheduling paradigm. In the third scenario, a fraction of exam slots are blocked to long-term follow-up exams and made available only closer to the exam date, thereby preventing long-term follow-up exams from filling the schedule and ensuring slots are available for non-follow-up exams. We examined the effect of these three scenarios on utilization and wait times, which we defined as the time from order placement to exam completion, during and after the holiday period.The baseline mean wait time for non-follow-up exams was 5.4days in our simulation. When no scheduling modifications were made, there was a significant increase in wait times in the week preceding the holiday when compared to baseline (10.0days vs 5.4days, p < 0.01). Wait times remained elevated for 4weeks following the holiday. Increasing imaging capacity during the holiday and post-holiday period by 20% reduced wait times by only 6.2% (9.38days vs 10.0days, p < 0.01). Increasing capacity by 50% resulted in a 7.1% reduction in wait times (9.28days, p < 0.01), and increasing capacity by 100% resulted in a 13% reduction in wait times (8.75days, p < 0.01). In comparison, using a rolling release model produced a reduction in peak wait times equivalent to doubling capacity (8.76days, p < 0.01) when 45% of slots were reserved. Improvements in wait times persisted even when rolling release was limited to the 3weeks preceding or 1week following the holiday period. Releasing slots on a rolling basis did not significantly decrease utilization or increase wait times for long-term follow-up exams except in extreme scenarios where 80% or more of slots were reserved for non-follow-up exams.A rolling release scheduling paradigm can significantly reduce wait time fluctuations around holiday periods without requiring additional capacity or impacting utilization.

Deep adversarial domain adaptation for hyperspectral calibration model transfer among plant phenotyping systems

Hyperspectral imaging has widely been used for plant phenotyping applications. Calibration transfer is crucial for eliminating the prediction drift when a model developed in one plant phenotyping system needs to be deployed in another system. In this study two approaches (Domain Adversarial Neural Network - DANN and Adversarial Discriminative Domain Adaptation – ADDA) for transferring a deep learning model across hyperspectral imaging-based plant phenotyping systems were presented. The proposed techniques employ adversarial learning to minimise the discrepancy between the spectral data of two imaging facilities in the feature space. The calibration transfer analysis was examined by collecting the hyperspectral images of maize plants in two phenotyping facilities equipped with different sensors covering the visible near-infrared (VNIR) region under different lighting conditions. The capability of the suggested methods to transfer a relative water content (RWC) prediction model was investigated. The results showed that the prediction R 2 improved from 0.603 to 0.849 and 0.843 and RMSE reduced from 23.52% to 14.15% and 12.73% for DANN and ADDA, respectively. The study showed that both approaches improved the performance of the transferred model compared to a similar deep learning model without adversarial transfer. Visualisation of feature space showed that both methods lead to similar source and target feature distributions, thus indicating that a prediction model developed using these common features can successfully be applied to both imaging facilities. The main benefit of the DANN and ADDA is that they do not need the standard samples to be imaged in two phenotyping systems or the collection of labelled data to carry out the transfer. The adversarial learning-based calibration transfer can promote the sharing of prediction models across different phenotyping systems. • Differences across phenotyping facilities hinders the application of exiting models. • Calibration transfer between different phenotyping facilities is critically important. • Adversarial domain adaptation based methods were proposed for calibration transfer. • Proposed methods resulted in RWC model shared between two facilities. • Proposed methods can help to eliminate the need of full recalibration.

COVID-protected pathways for image-guided lung cancer intervention during the COVID-19 pandemic: A cohort study.

To compare the experience of COVID-protected and mixed cohort pathways in COVID-19 transmission at a tertiary referral hospital for elective CT-guided lung biopsy and ablation during the COVID-19 pandemic. From September 2020 to August 2021, patients admitted for elective thoracic intervention were treated at a tertiary hospital (Site 1). Site 1 received patients for extracorporeal membrane oxygenation (ECMO) and invasive ventilation in the treatment of COVID-19. Shared imaging, theater, and hallway facilities were used.From April 2020 to August 2020, patients admitted for elective thoracic intervention were treated at a COVID-protected hospital (Site 2). No patients with suspected or confirmed COVID-19 were treated at Site 2.Patients were surveyed for clinical and laboratory signs of COVID-19 infection up to 30 days post-procedure. At Sites 1 and 2, patients (2.4%) were tested positive for COVID-19 at 10 and 14 days post-procedure.At Site 2, there were no COVID-19 positive cases within 30 days of undergoing elective thoracic intervention. A mixed-site method for infection control could represent a pragmatic approach to the management of elective procedures during the COVID-19 pandemic or for similar illnesses. Mixed-cohort infection control is possible in the prevention of nosocomial COVID-19 infection.

Accelerating integration of tobacco use treatment in the context of lung cancer screening: Relevance and application of implementation science to achieving policy and practice.

Based on the findings from the National Lung Screening Trial, the U.S. Preventive Services Task Force recommends annual low dose computed tomography (LDCT) lung cancer screening (LCS) among high-risk adults. Approximately 54% of individuals seeking LCS report current cigarette smoking. Effective smoking cessation interventions, offered at the time of LCS, enhances the health benefits of screening that are attributable to reductions in lung cancer overall and tobacco-related mortality. Considering these data, the Centers for Medicare & Medicaid Services' (CMS) 2015 decision to cover LCS with LDCT required that radiology imaging facilities make tobacco cessation interventions available for people who smoke. In February 2022, CMS reversed their 2015 coverage requirement for delivering tobacco use treatment at the time of LDCT; CMS retained the requirement for counseling during the shared decision-making visit prior to the exam. The policy change does not diminish the importance of offering high-quality tobacco cessation services in conjunction with routine LDCT for LCS. However, LCS programs face a range of barriers to implementing tobacco use treatment in their settings. As a result, implementation has lagged. Closing the "evidence to practice" gap is the focus of implementation science, a field that offers a set of rigorous methods and a systematic approach to identifying and overcoming contextual barriers to implementing evidence-based guidelines in a range of clinical settings. In this paper, we describe how implementation science frameworks and methods can be used to help guide LCS programs in their efforts to integrate tobacco use treatment and discuss policy changes needed to further facilitate the delivery of TUT as an essential component of the LCS process.

Access to diagnostic imaging and incidental detection of differentiated thyroid cancer in Ontario: A population-based retrospective cohort study

Global increases in thyroid cancer incidence (≥90% differentiated thyroid cancers; DTC) are hypothesized to be related to increased use of pre-diagnostic imaging. These procedures can detect DTC during imaging for conditions unrelated to the thyroid (incidental detection). The objectives were to evaluate incidental detection of DTC associated with standardized, regional imaging capacity and drivetime from patient residence to imaging facility (the exposures). We conducted a population-based retrospective cohort study of 32,097 DTC patients in Ontario, 2003–2017. We employed sex-specific spatial Bayesian hierarchical models to evaluate the exposures and examine the adjusted odds of incidental detection by administrative regions. Regional capacities of computed tomography and magnetic resonance imaging scanners are positively associated with incidental detection, but vary by sex. Contrary to hypothesis, drivetimes in urban areas are positively associated with incidental detection. Access to primary care may play a role in several administrative regions with higher adjusted odds of incidental detection.

Sample Size and Estimation of Standard Radiation Doses for Pediatric Brain CT.

Estimation of the standard radiation dose at each imaging facility is required for radiation dose management, including establishment and utilization of the diagnostic reference levels. We investigated methods to estimate the standard dose for pediatric brain computed tomography (CT) using a small number of data. From 980 pediatric brain CT examinations, 25, 50, and 100 examinations were randomly extracted to create small, medium, and large datasets, respectively. The standard dose was estimated by applying grouping and curve-fitting methods for 20 datasets of each sample size. For the grouping method, data were divided into groups according to age or body weight, and the standard dose was defined as a median value in each group. For the curve-fitting methods, logarithmic, power, and bilinear functions were fitted to plots of radiation dose against age or weight, and the standard dose was calculated at the designated age or weight using the derived equation. When the sample size was smaller, the random variations of the estimated standard dose were larger. Better estimation of the standard dose was achieved with the curve-fitting methods than with the grouping method. Power fitting appeared to be more effective than logarithmic and bilinear fittings for suppressing random variation. Determination of the standard dose for pediatric brain CT by the curve-fitting method is recommended to improve radiation dose optimization at facilities performing the imaging procedure infrequently.

Simulated daily readout for maintaining nuclear medicine education in residency training amidst declining case volume: evidence from the COVID-19 pandemic.

Simulated daily readout (SDR) is a teaching initiative in radiology and nuclear medicine developed to simulate a resident's experience during periods of case volume reduction. SDR was employed by many training centers during the coronavirus disease 2019 (COVID-19) pandemic. This study aimed to evaluate the perception of radiology residents on the effectiveness of SDR. The SDR was conducted in the nuclear medicine rotations from 2019 to 2020 during the shutdown of the radionuclide imaging facilities using a combination of strategies including case selection, assignment, reporting and feedback. A brief 8-item questionnaire with Likert scale values was completed by radiology residents who participated in the SDR-based nuclear medicine rotations. Thirty-five of 54 residents returned the questionnaire. The majority of residents affirmed the negative impact of the reduction in case volume on their training experiences and perceived that SDR could alleviate the effects. The SDR strategies perceived as more effective were targeted case selection, in-advanced assignment, verbal interpretation and reporting, and verbal feedback. The radiology residents perceived the SDR as an effective tool to preserve their training experiences. The SDR has the potential to be a useful initiative when teaching centers face the threat of declining case volume.

Pore Segmentation Techniques for Low-Resolution Data: Application to the Neutron Tomography Data of Cement Materials.

The development of neutron imaging facilities provides a growing range of applications in different research fields. The significance of the obtained structural information, among others, depends on the reliability of phase segmentation. We focused on the problem of pore segmentation in low-resolution images and tomography data, taking into consideration possible image corruption in the neutron tomography experiment. Two pore segmentation techniques are proposed. They are the binarization of the enhanced contrast data using the global threshold, and the segmentation using the modified watershed technique—local threshold by watershed. The proposed techniques were compared with a conventional marker-based watershed on the test images simulating low-quality tomography data and on the neutron tomography data of the samples of magnesium potassium phosphate cement (MKP). The obtained results demonstrate the advantages of the proposed techniques over the conventional watershed-based approach.

EP06.01-008 COVID-Protected Pathways for Image Guided Lunc Cancer Intervention During the COVID-19 Pandemic: A Cohort Study

EP06.01-008 COVID-Protected Pathways for Image Guided Lunc Cancer Intervention During the COVID-19 Pandemic: A Cohort Study

3D Selection of 167 Substellar Companions to Nearby Stars

We analyze 5108 AFGKM stars with at least five high-precision radial velocity points, as well as Gaia and Hipparcos astrometric data, utilizing a novel pipeline developed in previous work. We find 914 radial velocity signals with periods longer than 1000 days. Around these signals, 167 cold giants and 68 other types of companions are identified, through combined analyses of radial velocity, astrometry, and imaging data. Without correcting for detection bias, we estimate the minimum occurrence rate of the wide-orbit brown dwarfs to be 1.3%, and find a significant brown-dwarf valley around 40 M Jup. We also find a power-law distribution in the host binary fraction beyond 3 au, similar to that found for single stars, indicating no preference of multiplicity for brown dwarfs. Our work also reveals nine substellar systems (GJ 234 B, GJ 494 B, HD 13724 b, HD 182488 b, HD 39060 b and c, HD 4113 C, HD 42581 d, HD 7449 B, and HD 984 b) that have previously been directly imaged, and many others that are observable at existing facilities. Depending on their ages, we estimate that an additional 10–57 substellar objects within our sample can be detected with current imaging facilities, extending the imaged cold (or old) giants by an order of magnitude.