Preoperative Evaluation of Pulmonary Vascular Anatomy by Holograms

Preoperative Evaluation of Pulmonary Vascular Anatomy by Augmented Reality (Holograms) in Patients Undergoing Lung Resection

Pulmonary vascular anatomy represents a constant challenge during lung resection, because of its variability in terms of vascular branches and anatomical variations.

Preoperative standard computed tomography is not always sufficient to foresee tricky abnormalities; augmented reality, thanks to holograms creation, may offer additional data on pulmonary vascular anatomy and its relation with neoplastic tissue. The aim of this study is to assess the possibility of correctly predict number, location and potential anomalies of pulmonary vascular anatomy of the lobe to be resected in patients undergoing lung resection for cancer.

Patients will receive standard preoperative oncologic and functional assessment. Preoperative computed tomography (CT) - performed according to a specific protocol - will be performed. CT images will be subsequently elaborated to generate 3D images (holograms). Two radiologists and two thoracic surgeons will analyze CT images and report number of artery and vein branches for the lobe to be resected. Moreover they will report every anatomical variation, according to the normal anatomy. After that, the same two radiologists and thoracic surgeons will analyze the holograms and perform the same analysis as quoted above. Patients will undergo to the planned surgical resection. The operating team will report the exact number of artery and vein branches of the resected lobe as well as every anatomical variation. Preoperative CT and holographic findings of the radiologists and the thoracic surgeons will be matched with the report of the operating team.

An augmented reality (AR) system provides the surgeon with computer processed imaging data in real-time via dedicated hardware and software. The projection of AR is made possible by using displays, projectors, cameras, trackers, or other specialized equipment.

At present, the applications of AR are limited by the essential requisite of preoperative 3D reconstructions of medical images. It is possible to create these reconstructions by using commercial or self-made software from the Digital Imaging and Communications in Medicine (DICOM) format . The quality of a reconstruction depends on the quality of input data and the accuracy of the reconstruction system. Such reconstructions can be used for virtual exploration of target areas, planning an elective surgical approach in advance, and for better orientation and navigation in the operative field. AR is especially useful in visualizing critical structures such as major vessels, nerves, or other vital tissues. By projecting these structures directly onto the patient, AR increases safety and reduces the time required to complete the procedure. Moreover Augmented reality proved to be an effective tool for training and skill assessment of surgery residents, other medical staff, or students. Augmented reality can be used effectively for preoperative planning and completion of the actual surgery in timely fashion. The preoperative 3D reconstructed images can be modified and prepared for display in AR systems. Commonly, AR is used for tailoring individually preferred incisions and cutting planes, optimal placement of trocars, or to generally improve safety by displaying positions of major organ components. Another benefit of AR is the ability to aid surgeons in difficult terrain after a neoadjuvant chemotherapy or radiotherapy.

Studies suggest that AR systems are becoming comparable to traditional navigation techniques, with precision and safety sufficient for routine clinical practice. Most problems faced presently will be solved by further medical and technological research. Augmented reality appears to be a powerful tool possibly capable of changing the field of surgery through a rational use. In the future, AR will likely serve as an advanced human-computer interface, working in symbiosis with surgeons, allowing them to achieve even better results. Nevertheless, further advancement is much needed to achieve maximum potential and cost-effectiveness of augmented reality.

Inclusion Criteria:

• Planned anatomical resection for lung cancer
• Signed and dated informed consent indicating that the patient has been informed of all pertinent aspects of the study.
• Willingness and ability to comply with study procedures.

Exclusion Criteria:

• Age younger than 18 years
• Contraindications to general anesthesia
• Poor general clinical conditions ( ECOG PS >=2)
• Patients unable to provide informed consent