Global Health in Radiology: Evolution,Challenges,and a Framework for the Future

Introduction

Global health is often distinguished from public health by its focus on transnational determinants of health, cross-border collaboration, and health equity.^1,2 In practice, however, the boundary between the two is not fixed, and there is no universally accepted definition. Global health is more often characterised by its focus on inequities, shared vulnerabilities, and responses that take structural and ethical issues into account.^1-5 In radiology, this broader framing has not always been reflected in how the field is described. Global health radiology is still commonly discussed through the language of outreach, missions, and service trips. Although this language reflects an important part of the field’s history, it can understate the institutional, financial, educational, and implementation work required to build sustainable radiology capacity. ⁶ It can also give greater weight to the perspective of visiting institutions than to the needs and priorities of host health systems.

Several developments in global health and radiology have made this an important time to reconsider how global health in radiology is described and evaluated. The role of radiology within the global health agenda has become increasingly visible through the 2023 World Health Assembly resolution on strengthening diagnostics capacity, and the 2025 resolution focused specifically on medical imaging.^7,8 The World Health Organization (WHO) has estimated that around two-thirds of the world’s population does not have access to basic diagnostic imaging, including radiography and ultrasound.^9,10 In an international study across 10 low- and middle-income countries (LMICs), the median availability of essential diagnostics was 19.1% in primary care settings, and access to ultrasound and computed tomography was particularly limited outside referral centres. ¹¹ The Lancet Commission on diagnostics also identified poor access to diagnostics as a major and under-recognised barrier to effective health care globally. ¹² It further estimated that reducing diagnostic gaps across 6 priority health conditions could prevent around 1.1 million premature deaths each year in LMICs. ¹² Together, these findings show that infrastructure, workforce, and service design are central to improving access to imaging and to the wider goals of global health.

This narrative review provides a broad overview of global health radiology. It considers how the field has evolved, why radiology brings particular challenges in global health settings, which approaches have gained traction, where the main gaps remain, and where the field may need to go next. We argue that global health radiology is best understood as work to strengthen imaging systems, with attention to equity, sustainability, and implementation. This better reflects the practical work involved in building radiology capacity over time.

From International Outreach to Global Radiology

The modern global radiology literature emerged in response to major disparities in access to medical imaging across resource-constrained settings. Early RAD-AID white papers were particularly important in shaping the field because they moved discussion beyond equipment donation alone, and drew attention to wider issues affecting radiology service delivery, including sustainability, workforce training, digital infrastructure, and integration within health systems.^10,13 In doing so, they helped frame these as radiology-specific challenges rather than more general humanitarian concerns. This was an important step in establishing global radiology as a field with its own questions, priorities, and literature.

Since then, the field has expanded considerably. Organisations such as RAD-AID, RSNA Global Learning Centers, Radiology Across Borders, and Radiologists Without Borders have developed different models of engagement, including education, equipment planning, teleconsultation, and longer-term institutional partnerships.^14-17 Within training programmes, surveys from both the United States and Canada have also shown strong resident interest in global radiology, alongside ongoing structural barriers such as funding, protected time, mentorship, and limited curricular support.^18-22 Together, this literature suggests that global radiology has moved beyond ad-hoc extracurricular work, and has gained greater educational and organisational structure. At the same time, the extent and consistency of implementation still vary widely across institutions and settings.

The term “outreach” still shapes how much of global radiology describes itself, and its limitations should be acknowledged. It can emphasise the priorities and timelines of the visiting institution, suggest short-term involvement rather than sustained capacity building, and position imaging as a charitable addition rather than a core part of health systems. More recent global health scholarship has increasingly emphasised equitable partnerships, co-developed agendas, fair authorship, shared governance, and accountability to local priorities.^3,4 The extent to which these principles have been put into practice in global radiology requires continued reflection within the field.

Why Radiology Is Distinct Within Global Health

Radiology presents challenges that differ from many other areas of global health, although this is not always made explicit in the literature. Medical imaging services depend on capital investment, stable electricity, biomedical engineering support, equipment maintenance, digital infrastructure, radiation safety systems, and a skilled workforce. ²³ Workforce disparities are particularly pronounced. Frija et al reported a radiologist density of around 1.9 per million population in low-income countries, compared with 97.9 per million in high-income countries, and noted that migration from LMICs to higher-income settings further worsens these shortages. ²⁴ Even where imaging equipment is donated or successfully procured, services may still be difficult to sustain without reliable electricity, consumables, information technology systems, trained operators, and workable maintenance pathways.^13,24-26 These issues show that radiology capacity depends on more than equipment alone, and that weaknesses at any point in the system can limit the clinical and public health value of the investment.

Studies of imaging equipment in LMICs have consistently reported high rates of non-functional equipment, with maintenance problems, and supply chain failures often representing the main barriers to continued access, rather than initial procurement. ²⁴ In a foundational study, Perry and Malkin examined more than 112 000 pieces of medical equipment across 16 low-income countries and found that around 40% were non-functional. ²⁷ The main reasons were limited biomedical engineering support, weak health technology management, and inadequate infrastructure, rather than procurement itself. These findings showed that equipment donation alone is insufficient without systems to support maintenance over time. They also reinforce that global radiology requires more than capital planning, with equal attention to workforce training, biomedical engineering capacity, and reliable access to consumables, all of which are often underemphasised in programme design.

Medical imaging has relevance across a wide range of clinical areas, which contributes both to its value in global health and to the complexity of implementing it well. Imaging supports maternal health, trauma care, oncology, tuberculosis screening, congenital disease, emergency surgery, specialised healthcare areas, and increasingly primary care pathways.^12,24,28-30 This means that access to radiology can influence multiple parts of the health system at once. Improvements in medical imaging access may therefore have effects across several disease programmes, while gaps in access can worsen inequities across multiple areas of care in parallel. DeStigter et al proposed tier-based integrated medical imaging service delivery as a framework for planning imaging in relation to the capabilities and referral pathways of the wider health system, rather than through isolated and opportunistic equipment placement. ²⁶ By locating radiology within broader systems of triage, reporting, referral, and follow-up, this model highlights an important principle for sustainable service design that extends beyond the question of equipment procurement alone.

The economics of imaging add another layer of complexity that has not always been addressed clearly in operational terms within global health. The Lancet Oncology Commission estimated that expanding imaging capacity for cancer care in LMICs could produce substantial health and economic benefits over time, but also noted that the link between capital investment and realised value is not automatic. ³¹ The benefits of imaging depend on a series of decisions beyond initial acquisition, including modality mix, replacement cycles, siting, workflow design, staffing, uptime, and digital interoperability. These factors shape whether imaging services become durable public assets or remain underused and difficult to sustain. Recent work on financial reasoning in radiology has drawn attention to the importance of total cost of ownership, capital budgeting, and staged investment planning for long-term performance. ³² These considerations are especially important in resource-constrained settings, where the consequences of poor planning are often harder to absorb.

Current Models of Engagement

The global health radiology literature describes several broad models of engagement. Education and workforce development remain the most widely described, including longitudinal training partnerships, visiting faculty models, curriculum development, and global health pathways within residency programmes.^19-22 There has also been an important shift within this work towards bidirectional learning and the development of local trainers, rather than one-way knowledge transfer. Omofoye has argued that radiology education can itself function as a form of global health service, particularly when it is designed to strengthen local interpretive capacity and clinical decision-making, rather than mainly offering trainees from high-income settings exposure to unfamiliar pathology. ³³ This distinction matters in practice, as approaches centred on local capacity building are more likely to support lasting and locally owned capability, whereas models that primarily benefit visiting learners may offer limited long-term value for the host system, even when they are educationally worthwhile for those trainees.

A second model focuses on direct service delivery and capacity development, most often in ultrasound, plain radiography, and other context-appropriate areas of subspeciality imaging. Obstetric ultrasound has received particular attention because of its importance in maternal and fetal care, and because it can be delivered outside tertiary referral centres through task-shifted models. ²⁸ More broadly, point-of-care ultrasound has been proposed as an important modality for primary care in LMICs because it is portable, does not involve ionising radiation, and can be used for focused clinical questions.^29,34 Interventional radiology has also attracted increasing interest, although implementation remains limited by infrastructure needs, supply chain challenges, device costs, and the demands of procedural training and quality assurance. ³⁵ One recent example is the implementation of congenital cardiac computed tomography in a low-resource setting, which showed how protocolised practice, remote mentorship, and iterative quality improvement can expand clinical capability over time without requiring entirely new capital infrastructure. ³⁶ Together, this work suggests that global radiology does not need to be limited to basic imaging alone, and that under the right conditions, more advanced services can also be introduced safely and sustainably when training, oversight, and quality monitoring are built in from the outset.

Digital and remotely enabled radiology is another important area within global health radiology. This includes teleradiology, tele-ultrasound, cloud-based image sharing, and the use of radiology information systems and picture archiving and communication systems (RIS/PACS).^25,37 These technologies may help address workforce shortages and geographic barriers, but their value depends on how well they are integrated into wider service delivery. In practice, factors such as bandwidth, data governance, privacy, local workflow, and ongoing technical training all influence whether these systems work effectively.^37,38 Tele-ultrasound, for example, has shown promise in resource-limited settings, but its usefulness depends on task design, device usability, operator training, and whether the findings can lead to appropriate downstream clinical action. ³⁸ The recurring gap between technology deployment and measurable clinical benefit in this literature is an important signal that digital tools require as much implementation planning as physical infrastructure.

A fourth model, which has become more prominent in recent years, centres on technology leapfrogging, particularly through point-of-care ultrasound, low-field magnetic resonance imaging, and artificial intelligence.^29,39-42 Low-field portable MRI has attracted growing interest because it may reduce some of the infrastructure barriers associated with conventional MRI, including power demands and siting requirements. However, early implementation has also shown that maintenance, training, selection of appropriate clinical indications, and integration into existing reporting workflows remain important challenges.^41,42 Artificial intelligence has been discussed in similar terms, particularly as a possible response to radiologist shortages in LMICs through automated detection and triage. At the same time, the literature increasingly shows that effective AI implementation depends on digital infrastructure, governance, local validation, workflow integration, and gradual deployment rather than rapid scale-up.^41-43 Algorithms developed mainly in high-income settings may not perform well on imaging acquired using different equipment, protocols, or patient populations, which has clear equity implications, and requires careful prospective evaluation before wider use. ⁴⁴ Overall, these technologies are promising, but their value depends on how they are implemented in practice.

Persistent Challenges

Fragmentation remains a major challenge in global radiology and is one that the literature needs to address more directly. Much of this work is still episodic and is often not well connected to national diagnostic plans, referral pathways, financing structures, or long-term workforce strategies.^13,24,26 As a result, the published literature contains many descriptions of well-designed initiatives, but fewer examples of radiology services that have been integrated sustainably at scale; with further impact on scholarship in the post-COVID era. ⁴⁵ The gap between a successful pilot and a self-sustaining service remains substantial. Closing that gap requires institutional continuity, political commitment, and multi-year financial planning, which short-term models of engagement are rarely well-positioned to support.

A second challenge relates to the ethics and politics of global health partnerships. Global health scholarship has increasingly drawn attention to questions of agenda-setting, authorship equity, reciprocity, and the risk that extractive or paternalistic dynamics may persist even within work presented as capacity building.^3,4 These issues are also relevant in radiology. The technological and financial demands of radiology can create imbalances in who defines success, who makes procurement decisions, who receives academic credit, and whose institutional timelines shape a collaboration. Greater attention to these issues would strengthen the global radiology literature. Equity needs to be examined both in how this work is described, and in how partnerships are designed and carried out in practice.

Evaluation frameworks also remain underdeveloped relative to the complexity of what global radiology programmes are trying to achieve. Most published reports rely on process measures, such as the number of trainees reached, scans performed, or machines installed. ⁴⁶ These measures are useful, but they provide only a partial picture. They tell us little about whether services remain reliable over time, whether imaging is integrated into clinical pathways, whether patients can access definitive care after imaging, how patients experience these services, or whether programmes remain functional once external support is reduced. This is not unique to radiology, but it is particularly important in this field. In radiology, technical deployment can easily be mistaken for meaningful system benefit, even though the value of an imaging service is only fully understood through longer-term clinical and operational outcomes.

Patient-centred outcomes remain largely absent from evaluations of global radiology initiatives, despite increasing work on PROM methodology in radiology within high-income settings. Evaluation in radiology has traditionally focused on technical measures, such as image quality, diagnostic accuracy, and reader concordance. These measures are important, but they do not capture the wider informational, emotional, physical, and logistical effects that imaging may have on patients.^46,47 In global health settings, these issues may be particularly important. Travelling long distances to access imaging, waiting for results, understanding what those results mean, and being treated with dignity throughout the care encounter all shape how imaging services are experienced by patients. Delayed or absent follow-up after an abnormal imaging finding is also a patient-centred issue that process measures are not well-suited to capture. Greater use of PROM frameworks in global radiology evaluation would help strengthen how these programmes are assessed and would provide a fuller account of whether they are delivering value to the patients they are intended to serve.

Financing is often recognised as a barrier in global radiology, but less often approached as a core design issue. Sustainable radiology services depend on selecting modalities that match real maintenance capacity, planning for lifecycle costs and replacement cycles, designing appropriate utilisation pathways, and recognising the opportunity costs of poorly sequenced capital investment.^13,24,31,32 Programmes that do not engage seriously with total cost of ownership, uptime targets, or procurement strategy may produce technically impressive acquisitions that become increasingly difficult to sustain after handover. Treating financing as part of implementation, rather than as something to secure at the outset and then move past, may be one of the most important shifts global radiology programmes can make.

A Future Agenda: Towards Implementation-Informed Global Medical Imaging Systems Strengthening

The next phase of global health radiology should focus on how imaging services are implemented, governed, financed, evaluated, and adapted so that they remain durable, equitable, and locally valuable over time. Decades of work have already shown that imaging can be introduced in underserved settings. The more pressing question now is how to build services that last, are meaningfully integrated into local health systems, and communicated about in sustainable ways. ⁴⁸ We propose 5 interrelated pillars (Figure 1) for this next phase.

OPEN IN VIEWER

Figure 1.

Five-pillar framework for global health radiology as imaging systems strengthening.

The first pillar is equitable partnership design, supported by leadership structures that are fit for this work.^49-51 Global radiology programmes are more likely to achieve durable outcomes when they are built around locally defined priorities, shared agenda-setting, mutual accountability, fair attribution, and realistic timelines.^3,4 External partnerships still have an important role, particularly where they provide technical expertise, funding, or political support that may not otherwise be available. However, these partnerships need to be organised around the priorities of the host health system rather than donor timelines or the academic interests of visiting institutions. Local ownership and stewardship also need to be built into programme design from the beginning, rather than treated as something to arrange at the point of handover. In practice, this means involving local clinical, technical, administrative, and policy stakeholders early in the process, agreeing on success measures collaboratively, and addressing the practical conditions, such as salary support, protected time, and recognition, that allow local champions to sustain programmes over time. Because radiology capacity depends on decisions that are specific to imaging service delivery, these stakeholders should include radiology leaders and experts with a deep understanding of imaging systems, clinical workflows, equipment lifecycle management, digital infrastructure, and workforce planning. Involving this expertise from the outset helps ensure that partnerships are designed around the operational realities of radiology and its long-term sustainability, rather than solely around clinical or donor priorities.

The second pillar is financial realism. Radiology is one of the most capital-intensive areas of healthcare, and global radiology programmes need to account from the outset for total cost of ownership, service contracts, consumables, digital infrastructure, power requirements, operator training, and replacement planning.^24,31,32 Attention to these issues is central to whether programmes remain functional over time. In many settings, the most appropriate starting point may not be the most advanced modality available, but the service that is best matched to local capacity for maintenance, clinical integration, and ongoing use. The principle of context-appropriate sequencing, with service complexity increasing gradually as operational capacity develops, deserves greater attention within the field.

The third pillar is implementation science and change management. A persistent challenge in global radiology is not only limited technology or funding, but the difficulty of moving from programme introduction to sustained routine practice. Implementation science offers a useful framework for understanding this problem. Frameworks such as the Consolidated Framework for Implementation Research (CFIR), implementation outcomes taxonomies, and RE-AIM provide structured ways of examining adoption, acceptability, feasibility, fidelity, maintenance, and reach.^52-55 These concepts are directly relevant to imaging programmes in any setting. CFIR, for example, draws attention to factors such as organisational culture, leadership, and policy context, all of which can influence whether a programme becomes part of routine care or fails to take hold. Change management principles are also relevant, including assessing stakeholder readiness, planning communication, mapping workflows, and adapting programmes over time. ⁴⁷ These approaches can support the introduction of new imaging equipment, digital systems, AI-supported workflows, and revised reporting pathways. Using these frameworks prospectively, rather than only to explain why a programme struggled after implementation, may help strengthen implementation outcomes in global radiology.

The fourth pillar is evaluation that reflects the complexity of what global radiology programmes are trying to achieve. In addition to utilisation measures, evaluations should include service uptime, diagnostic turnaround time, referral completion, linkage to treatment, and patient-reported outcomes and experiences.^46,47 PROM-informed evaluation is a particularly important and underused area in this literature. The value of imaging extends beyond diagnostic accuracy alone. It also includes the reassurance of a timely normal result, reduced uncertainty, the burden of travelling to access care, the quality of communication around findings, and whether the imaging encounter is experienced with dignity and respect. These aspects of care may be especially important in geographically dispersed or under-resourced settings, where the effort required to access services is itself a meaningful patient-centred outcome. Developing, validating, and implementing PROMs that are appropriate for global radiology settings, and incorporating them into programme evaluation, would be an important and achievable step for the field. Work in other clinical areas may also help inform how PROMs are introduced and sustained in radiology practice.^56-67

The fifth pillar is policy alignment and long-term sustainability. The 2023 and 2025 World Health Assembly resolutions provide an important basis for positioning radiology within national diagnostic strategies and universal health coverage planning.^7,8,12 These resolutions also build on earlier developments, including the WHO’s first Model List of Essential In Vitro Diagnostics in 2018, which highlighted the importance of diagnostics within national health planning, ⁶⁸ and the alignment of imaging access with Sustainable Development Goal 3, which calls for healthy lives and universal health coverage by 2030. ⁶⁹ Engaging with these policy frameworks, and with the ministries of health, national health authorities, and financing bodies responsible for implementing them, places global radiology within the wider work of health-system strengthening rather than limiting it to institutional partnership alone. Sustainability should also be understood broadly. This includes workforce sustainability through training and retention, environmental sustainability through attention to equipment lifespan and energy use, and service sustainability through programme design that avoids creating isolated areas of advanced imaging without the referral pathways and operational systems needed to support them.^7,24,70 This breadth of dependence has grown more pressing as medicine itself has changed. Over recent decades, diagnostic imaging has become indispensable across nearly every clinical speciality, and the expansion of oncology and other chronic disease pathways has created a steadily rising need for longitudinal follow-up and surveillance imaging. Future implementation frameworks should therefore plan for current diagnostic demand in addition to the escalating volume of repeat and surveillance studies that accompany contemporary practice, reinforcing that radiology must be treated as a core component of health-system planning and capacity building rather than a discrete or one-time addition. A programme that delivers high-quality imaging for only a few years before organisational or financial failure cannot be considered successful, regardless of how strong its interim metrics may have appeared.

Why Reframing Global Radiology Matters

There remains a risk that global radiology is viewed mainly as a well-intentioned extension of volunteer work, driven by individual enthusiasm and assessed through counts of scans performed or trainees reached during short-term initiatives. That view understates both the importance of imaging access within health systems and the level of practical and intellectual work required to build radiology services that last. Global radiology increasingly sits within broader questions of diagnostics policy, capital planning, digital infrastructure, workforce development, implementation, and patient-centred evaluation. Having the field of global radiology framed in these terms is more likely to produce rigorous scholarship, stronger evaluation methods, and programmes that are better designed for long-term sustainability than one framed mainly around service trips and philanthropy.

For training programmes, this reframing has clear implications for curriculum design and competency development. A strong global radiology curriculum should include more than exposure to different diseases or cross-cultural clinical settings, and should also address partnership ethics, health systems strengthening, procurement and equipment lifecycles, quality improvement, implementation science, financial reasoning, and patient-centred evaluation.^{18,20,22,32,46,47,52-55} Residents who develop these skills alongside their clinical training are better positioned to contribute meaningfully to global radiology work, including programme design, evaluation, and ongoing improvement. Effective global radiology practice requires a broader set of competencies than image interpretation alone, and training programmes that reflect this are likely to prepare residents more effectively for the field.

Conclusion

Global health in radiology has reached a point where more rigorous conceptual and evaluative standards are both needed and achievable. The field is best understood through the work of building imaging systems that are equitable, sustainable, and able to function in practice within resource-constrained settings. This includes capital planning, digital infrastructure, workforce development, maintenance systems, integration into clinical workflows, and evaluation that captures outcomes for both patients and health systems. It also creates space for important areas of future work, including financing approaches that support long-term service viability, implementation frameworks that improve adoption and sustainability, patient-reported outcome measures that better capture the value of imaging, and partnership models that are equitable, accountable, and centred on local ownership. The aim of global radiology should be to work with partners to build imaging services that are designed from the outset to last.