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Robotic prostatectomy is a surgery for treating localized prostate cancer. The ARssist system is a novel augmented reality system designed for the assistant surgeon, allowing delivery of augmented reality information via Microsoft HoloLens 2 (a head mount display developed by Microsoft) to better delineate the 3-D operative environment and enable better visualization. To date, there is no prospective study on the clinical performance and utilization of the ARssist system. This study is to evaluate the clinical feasibility and safety of the ARssist system during robotic surgery with the da Vinci Xi system.

The da Vinci robotic surgery system offers advantages such as immersive three-dimensional visualization, intuitive control, and high degree of movement freedom to the chief surgeon. However, major surgery remains a team-based effort. Apart from the chief surgeon who remotely controls the da Vinci system at the console, the success of robotic assisted surgical procedures also relies on the assistant surgeon positioned at the patient side, who provides assistance laparoscopically. Throughout a robotic assisted operation, the patient side surgeon is responsible for tasks such as the exchange of instruments, retraction of tissue to enhance operative fields, manipulation of instruments, etc. Literature has demonstrated that the performance of the assistant surgeon has an effect on the outcomes of robotic surgery such as operative time.

Traditionally the patient side surgeon relies on the monitor mounted on the vision cart to guide his/her movement. The monitor provides real-time relay of the image captured from the endoscope, but does not provide the full three-dimensional stereo endoscopy view unless set up with specialized stereo-vision equipment. The position of the monitor is also often awkward, creating problems such as obstructed views and non-ergonomic positioning of the patient side surgeon to overcome the view obstruction. The complex three-dimensional set-up of endoscope, robotic instruments, and hand-held instruments inside the patient body could prove difficult to imagine from the patient side surgeon's perspective, and guesswork could be involved during transfer of instruments/objects towards the operative field as the hand-held instruments are often out of the visualized field of the endoscope.

Augmented reality (AR) technology delivered via optical see-through head-mounted display (OST-HMD) could potentially be the solution to the aforementioned issues. OST-HMD, such as Microsoft HoloLens, can superimpose computer graphics on top of real-world view through optical combiners. The clinical application of such a technology has been gaining interest in the surgical community, with preliminary study demonstrating feasibility of AR technology in ureteroscopic procedures.

The ARssist system is a novel AR system designed for the patient side surgeon in robotic assisted surgeries. It integrates the da Vinci surgical system and Microsoft HoloLens, and provides valuable AR information to the patient side surgeon including (i) three-dimensional real-time rendering of the endoscope, robotic instruments, and hand-held instruments within the patient body, and (ii) real-time stereo endoscopy that is configurable for the assistant surgeon's preferred hand-eye coordination. The ARssist system would in theory grant the patient side surgeon improved orientation and navigation of hand-held laparoscopic instruments, thus improving their laparoscopic performance and the performance of the surgery as a whole.

Based on the Innovation, Development, Exploration, Assessment, Long-term Study (IDEAL) Collaboration group methodology of promoting surgical innovation and research through planned prospective studies within an established staged process, we propose a stage 1 (Innovation) study to evaluate the feasibility and safety of the ARssist system.

Inclusion Criteria:

• Age ≥ 18 years old with informed consent
• Suitable for minimally invasive surgery
• Clinically diagnosed with urological conditions that are indicated for robotic assisted radical prostatectomy with or without lymph node dissection

Exclusion Criteria:

• Body mass index ≥ 35 kg/m2
• Contraindication to general anaesthesia
• Severe concomitant illness that drastically shortens life expectancy or increases risk of therapeutic intervention
• Untreated active infection
• Uncorrectable coagulopathy
• Presence of another malignancy or distant metastasis
• Emergency surgery