Assessment of a Hexapod Surgical System for Robotic Micro-Macro Manipulations in Ocular Surgery

Abstract

Purpose: Robotic intraocular microsurgery requires a remote center of motion (RCM) at the site of ocular penetration. We designed and tested the Hexapod Surgical System (HSS), a microrobot mounted on the da Vinci macrorobot for intraocular microsurgery. Material and Methods: Translations and rotations of the HSS were tested for range of motion and stability. Precision and dexterity were assessed by pointing and inserting a coupled probe into holes of various sizes. The stability of a nonmechanical RCM was quantified. HSS functionalities were observed on porcine eyes. Results: The HSS maximal translations were 10 (x and y axes) and 5 cm (z axis). The maximal rotations were 15 and 22° (x and y axes). The precision was within 0.5 mm away from targets in 26/30 tests and maximal in 16/30 tests. The mean translational and rotational stability at the tip of the probe were 1.2 (0.6–1.9) and 1 mm (0–2), respectively. The average dexterity times were 5.2 (4.4–6.5), 7.1 (5.6–10.8) and 12.3 s (7.8–21.7) for 5-, 2- and 1-mm holes, respectively. The RCM was stable (within 0.1 mm). A vitreous cutter coupled to the HSS moved into porcine eyes through a sclerotomy with a stable RCM. Conclusion: The HSS provides an RCM dedicated for intraocular robotic surgery with a high level of precision and dexterity. Although it can be further improved, the micro-macro robotic system is a feasible approach for ocular surgery.

Robot-assisted intraocular surgery: development of the IRISS and feasibility studies in an animal model

“…By mounting a microrobot, the Hexapod Surgical System, to the da Vinci macrorobot, an RCM located at the site of ocular penetration was achieved. 16 Another adaptation, the Microhand (consisting of four fingers), was designed to mimic a human hand while being pneumatically controlled, allowing titration of grasping force. 17 The steady-hand manipulator 18,19 and Micron 20 were two independently developed instruments capable of tremor filtration for microsurgical procedures.…”

Robotic Vitreoretinal Surgery

“…This unnecessary stress was due to the remote center of motion (RCM) that was located away from the sclerotomy site, which generated tension at the entrance site. As a result, the Hexapod Surgical System (HSS) was developed for use with the Da Vinci system to provide an RCM at the site of ocular penetration, leading to improved dexterity for ocular surgery(16). …”

Robotic Eye Surgery: Past, Present, and Future

“…By mounting a micro robot, the Hexapod Surgical System (HSS), to the Da Vinci macro robot, a remote center of motion at the site of ocular penetration can be achieved (Figure 3). The precision and dexterity of this approach was validated by successful insertion of a vitreous cutter through a sclerotomy in porcine eyes [16]. Another adaptation, known as the "Micro hand," was equipped with micro electromechanical systems (MEMS) technology.…”