Highlights

The articles reviewed highlight various benefits and challenges associated with the implementation of innovative technologies in a surgical setting. According to Simone et al. [23], MR proved to be a valuable tool for continuing education, allowing remote mentoring, enhanced visualization of medical data, while providing a better identification of anatomy and related anomalies. Stefan [24], in their study, explores simulated workplaces and discusses a comprehensive approach to computer-assisted assessment, emphasizing empirical validity, realistic contextualization, and the ability to provide immediate feedback. Cen [25] demonstrates the wide application range of MR in OR by the use of 3D cardiac models in conjunction with VR and MR to provide better anatomical understanding, surgical simulation, and intraoperative decision support. In addition, Saito [26] emphasizes standardization and contextualization in surgical performance assessment, supported by evidence of validity in different domains. Cartucho and Shapira [27] proposes an integrated platform for multiple imaging modalities, with an interactive 3D model and innovative functionalities, particularly applicable to vascular neurosurgery. Galati et al. [28] highlights the utility of MR for training and telementoring, emphasizing improved efficiency and image quality.

Based on the reviewed articles, MR technology offers significant advantages in the operating room, enhancing the overall surgical experience and outcomes. MR allows surgeons to visualize anatomical structures in 3D and superimposed images on the actual patient, which facilitates the understanding of complex anatomy [25,26,27,28]. This capability not only aids in precise preoperative planning, by allowing detailed preparation and simulation, but also enhances surgical accuracy with real-time overlays during procedures [25,26,27,28]. Additionally, MR can reduce operative time by providing precise, real-time information, thus improving safety and efficiency [25,26,27,28], which are highly relevant for the patient, for the surgical team and ultimately for the healthcare institution. This technology is also invaluable for medical training, not only offering realistic simulations while enabling instant feedback, but also allowing real-time remote collaboration and support for continuous learning [23,24,25]. These features collectively contribute to an effective reduction in medical errors and support to an integrated approach to healthcare, seamlessly connecting with other electronic health systems [23,24,25,26,27,28].

Table 6 summarizes the main advantages and highlights the multifaceted benefits of utilizing mixed reality (MR) in medical education and practice.

Table 6 Summary of the identified advantages

In the process of conducting this systematic review, several limitations were identified in the use of MR in the OR. These limitations, detailed in Table 7, span various dimensions, including cost, time, technology, adherence to guidelines, privacy and ethics, among others, can constitute challenges for the introduction and operation of this new technology.

Table 7 Summary of the identified limitations

However, the implementation of MR in the operating room has yet some open challenges. The cost of MR systems, including hardware and software, can be a significant barrier for many healthcare institutions [23]. Additionally, healthcare professionals may require substantial training and time to adapt to these new technologies, which can be a daunting task [23,24,25]. The reliance on technology also poses risks, such as an eventual technical failure during critical procedures [25,26,27,28]. Furthermore, issues such as data integrity, privacy, and security are paramount concerns, as MR systems often involve the handling of sensitive patient information [25,26,27,28]. Physical interference with surgical procedures and the potential discomfort caused by prolonged use of MR devices are additional identified limitations [23,24,25]. Lastly, the fast evolution of technology may require frequent updates, adding to the long-term costs and complexity of maintaining MR systems in the surgical environment [23].

The summary presented in Table 7 provides a comprehensive overview of these limitations, offering a clear framework for understanding the encountered challenges.

MR technology offers a broad range of application possibilities. In the context of OR and based on the reviewed articles, a summary of the main areas where MR can have an impact is presented in Table 8.

Table 8 Studies coverage grouped by contextualization area

In summary, mixed reality technology can provide several benefits during a surgical procedure. Some of these advantages include augmented visualization, which allows direct visual information to be superimposed on the surgeon’s field of view, providing an improved perspective of anatomy and surgical instruments.

In addition, HMD can provide precise, real-time gesture guidance to help the surgeon navigate and perform procedures with greater accuracy. The ability to access critical clinical process data is another benefit, displaying important information such as medical images, diagrams or patient data without the need to divert attention to monitors or external devices. Real-time communication could be facilitated, allowing instant collaboration with other healthcare professionals during the procedure, either participating in the same room or participating remotely.

Finally, HMD and MR technology can be useful in education and training, allowing medical trainees and students to observe procedures in real time, from the unique surgeon’s perspective, and gain practical experience.

Answer to Research Question

In the introduction of this manuscript a research question was defined, as transcribed here "Among surgical teams (P), how does the incorporation of mixed reality tools (I) impact surgical procedures (O) when compared to conventional methods (C)?".

A beneficial impact is mentioned by several authors. In fact, from the four studies that addressed the use of MR during surgery [25,26,27,28], in all cases, there is evidence of benefits compared to conventional surgery. These benefits encompass easier understanding of procedures, increased accuracy, improved safety, and reduced operative time, among others.

The cost effectiveness of a specific procedure also impacts the surgery, which is mentioned in most articles. In [23], the cost aspect of Mixed Reality (MR) solutions is examined, with special reference to a low-cost implementation. The other studies within the selected literature explore different supporting architectures, each serving different purposes and indicating a wide range of associated costs. It is noteworthy, however, that the dynamic nature of the technology evolution and the expected decrease in the cost of hardware devices suggest a trend toward increased performance. This trajectory points to a prospective reduction in the barriers to access MR solutions, highlighting the potential for increased affordability and widespread availability in the future. From an institution’s perspective, given these benefits, investing in MR solutions may prove to be the most appropriate way to reduce surgery time while improving surgical outcomes, contributing to reducing overall operational costs.

Another relevant impacting factor, covered by three studies [23,24,25] is the ability to use MR technology for learning. The authors of these studies agree that simulation shortens the learning curve and is more cost-effective and time-efficient than traditional methods. Simulation in a safe environment also showed to be crucial for skill development and retention. The ability to teach remotely and share perspectives is also a highly valued benefit of MR. In addition, MR provides assessment methods for immediate feedback and allows for scenario repetition to track performance improvement [29].

Opportunities for MR use in OR

The integration of mixed reality (MR) technologies in operating rooms presents substantial promise for enhancing surgical precision, training, and overall patient outcomes. However, one of the critical barriers to the widespread adoption and effective utilization of these technologies is the challenge of interoperability between different systems. Mixed reality systems often rely on a complex amalgamation of software and hardware components, including headsets, sensors, imaging devices, and surgical instruments. These components are frequently developed by different manufacturers, each with their own proprietary protocols and standards. This lack of standardized communication protocols hinders seamless integration and data exchange between devices, leading to inefficiencies and potential errors during surgical procedures.

For instance, current MR systems might struggle to synchronize real-time data from disparate sources such as patient monitoring systems, radiologic imaging, and surgical navigation tools. This discordance can result in delays or inaccuracies in the information presented to the surgeon, thereby affecting decision-making processes. Furthermore, the need for manual data input or adjustments due to non-compatible systems diverts the surgeon's focus from the patient, potentially compromising the quality of care. Addressing interoperability issues requires the development and adoption of universal standards and protocols that facilitate seamless data exchange and integration across various MR systems and devices.

Additionally, current MR hardware presents limitations that constrain its practical application in the operating room. One notable limitation is the bulkiness and weight of existing MR headsets. These devices can be cumbersome, leading to discomfort during prolonged use and potentially impeding the surgeon's dexterity and range of motion. Future MR hardware needs to be lightweight, ergonomically designed, and adaptable to long surgical procedures without causing strain or fatigue.

Another critical area for improvement is the precision of finger tracking and hand gestures. Accurate finger tracking is essential for surgeons to manipulate virtual objects, navigate through medical images, and interact with MR interfaces effectively. Current systems often suffer from latency issues and lack the fine motor control required for delicate surgical tasks. Advancements in sensor technology and machine learning algorithms could enhance the accuracy and responsiveness of finger tracking, making MR interfaces more intuitive and reliable for surgical use.

Moreover, the practicality of MR hardware in sterile environments remains a challenge. Devices must be easily sterilizable or designed to maintain sterility throughout procedures. Future MR solutions could incorporate materials and designs that facilitate quick and effective sterilization, ensuring compliance with stringent surgical hygiene standards.

The integration of haptic feedback in MR systems is also important, since it could significantly enhance their utility in the operating room. Haptic feedback provides tactile sensations that can simulate the feel of tissues and instruments, offering surgeons a more immersive and informative experience. While current MR hardware typically lacks this capability, future developments could incorporate advanced haptic technologies to replicate the tactile feedback necessary for intricate surgical procedures.

Study Limitations

Despite the rigorous methodology that was employed in this systematic review, several limitations must be acknowledged:

1.

Search Strategy Limitations: Our search was confined to six major databases and did not include a comprehensive search of grey literature, which may have led to the exclusion of relevant studies not indexed in these databases. Furthermore, we restricted our search to English-language publications, potentially introducing language bias. In addition, the results are obtained from an initial search query that involves a personal selection of keywords. Distinct search terms can lead to distinct results.

2.

Publication Bias: There is an inherent risk of publication bias, as studies with positive findings are more likely to be published than those with null or negative results. This bias could have influenced our overall findings.

3.

Study Selection and Inclusion Criteria: The inclusion criteria were designed to ensure relevance and quality, yet they may have excluded pertinent studies, especially those with broader or slightly differing focuses. Additionally, the included studies exhibited considerable heterogeneity in terms of methodologies and outcome measures, which complicates direct comparisons and synthesis of results.

4.

Quality of Included Studies: The quality of the included studies varied, with some studies exhibiting distinct methodological approaches. This variability can impact the confidence in the pooled results.

5.

Data Extraction and Synthesis: Although a rigorous data extraction process has been employed, there remains the possibility of human error. The diversity in study designs and outcome measures presented challenges in synthesizing the data, necessitating cautious interpretation of the pooled findings.

6.

Generalizability of Findings: The generalizability of our findings is limited by the specific populations and settings of the included studies. As most studies were conducted in high-income countries, the applicability of the results to low- and middle-income settings is uncertain since the cost of HMD and MR technology can still be a limiting factor.

7.

Temporal Limitation: Our search strategy included studies published between 2018 and 2023. Given the rapidly evolving nature of this field, it is possible that newer studies have emerged that were not included in our review.

8.

Number of articles: While a revision based on a modest selection of six articles may offer a limited scope, it remains a valuable endeavor, especially given the timeliness of the topic under consideration. Collectively, the six selected articles help provide an initial overview that helps to describe the current landscape of the topic. This focused examination allows for a nuanced exploration of the benefits, limitations, and emerging opportunities associated with the topic.

Also, the inherent novelty of the topic, coupled with the insights provided by these selected articles, enhances the current topic understanding and lays the groundwork for further comprehensive research. As the field evolves, these initial findings can serve as a foundational framework for future research, guiding scholars toward a deeper understanding of the intricacies surrounding the topic.

By transparently acknowledging these limitations, the authors aim to provide a balanced context for the interpretation of the reported findings and guide future research efforts in this domain.