Minimally invasive intervention techniques have become increasingly important in clinical practice, with the advantages of minimal trauma, reduced bleeding, and quick postoperative recovery. However, these techniques have limited visual fields or operating spaces due to the small incision size and the need to minimize damage to normal tissue. Consequently, preoperative planning and operation under image guidance are necessary. Commonly used image guidance in clinical practice includes computed tomography (CT), magnetic resonance imaging (MRI), ultrasound imaging and X-ray fluoroscopy, etc. Nevertheless, these guidance methods have limitations in terms of visualizing and perceiving surgical information. Firstly, the two-dimensional screen used in the image guidance lacks stereoscopic vision, making it difficult to observe complex three-dimensional anatomical structures. Secondly, the operator's attention needs to be switched repeatedly between the screen and the surgical position, which poses a problem for hand-eye coordination. Thirdly, the above image guidance methods are difficult to track or perceive the relative positions of the patient's lesions and surgical tools in real-time, continuous, and accurate manner. Therefore, the success of a surgical procedure heavily relies on the doctor's experience and spatial imagination, which carries the risk of imprecise treatment and potential complications. Moreover, current minimally invasive interventions face challenges in achieving precise control over the treatment range due to limitations in the surgical treatment form (mechanical resection, heat, or radiation-based forms) or a lack of intraoperative treatment status monitoring.

In recent years, optical technology has rapidly developed and been widely applied in the diagnosis and treatment in biomedical field. In the field of minimally invasive intervention, optical assistance and laser ablation technologies play a crucial role in improving surgical precision and safety. Among them, augmented reality (AR) can provide new intraoperative information visualization schemes; optical tracking and sensing technology can provide quantitative spatial information and lay the foundation for precise surgical operations. Laser energy, with its excellent spatial directionality and flexibility, can be delivered to lesions through slender optical fibers and, when combined with intraoperative MRI temperature monitoring, can achieve more precise therapeutic effects. At the same time, the rapid development of artificial intelligence and its fusion with optical technology are promoting the development of minimally invasive interventions towards intelligent, precise, and personalized directions. Therefore, summarizing the optical assistance and laser ablation techniques is necessary to guide future development of this field.

In this paper, the research progress of optical assistance and laser ablation technologies is reviewed based on three aspects: (1) augmented reality; (2) optical tracking and sensing; (3) laser ablation.

The existing research on AR devices mainly includes three forms (Fig. 2): monitor-based, projection-based, and optical see-through. Among these, optical see-through head-mounted AR is currently the leading trend in development. Although numerous AR research studies have been conducted on minimally invasive interventions for different types of diseases (Fig. 3), actual clinical applications are still relatively scarce. This is largely due to the insufficient accuracy, discomfort, and inconvenience of current AR devices. Future research will primarily focus on the core technology of AR, specifically display, tracking, and registration. Artificial intelligence methods will play a crucial role in advancing these areas.

Optical tracking and sensing provide valuable quantitative information, including the position and shape of surgical tools and multi-dimensional tissue information. Current research primarily focuses on optical tracking, fiber Bragg grating (FBG), and optical imaging. Optical tracking is currently used in many minimally invasive procedures (Fig. 5), but it still has some limitations, such as the problem of occlusion of optical tracking equipment and image registration efficiency. With the increasing amount of information in modern surgery, the fusion of multiple information sources has become a new research trend, offering new solutions for markerless localization and tracking. In the future, intelligent localization, registration, and understanding of surgical scenes will be the focus of research. Additionally, perceiving multi-dimensional information of tissues is also an important development direction for surgical navigation. Researchers are increasingly paying attention to the application of FBG-based multi-dimensional information sensing in minimally invasive surgery (Fig. 6). Optical surface reconstruction and imaging, as important means of perceiving multi-dimensional tissue information, will be further integrated with artificial intelligence algorithms to make information processing more intelligent.

Laser ablation is an important form of minimally invasive intervention therapy and has been applied to the treatment of tumors and vascular diseases. Currently, MRI-guided laser ablation has shown unique advantages in precise treatment (Fig. 8). However, improving the precision of ablation therapy is still the focus of current research. Achieving this goal depends on intelligent processing of imaging information, such as deep learning-based anatomical structure segmentation and personalized precise ablation simulation prediction, as well as the development of assisted robots and intraoperative temperature monitoring technology. In addition, the use of lasers for thrombus treatment is still a relatively new field, and many studies are exploring the combination of laser thrombolysis with intraoperative imaging (such as optical CT) from the perspective of precise treatment, which will be the focus of future development.

With the rapid development of artificial intelligence, optical assistance and treatment technologies have seen new advancements in minimally invasive therapy by integrating with multidisciplinary fields such as computer vision, information science, and material science. AR technology provides a new visualization method and enhances doctors' confidence in their operations. Optical tracking and sensing make surgery more precise, while laser ablation has demonstrated advantages in precise treatment. Currently, there are numerous related studies, and we have reason to believe that intelligent optical assistance and treatment technology will continue to advance, leading to more intelligent, precise, and personalized minimally invasive interventions in the future.