Image-guided, surgical robot-assisted percutaneous puncture of the foramen ovale and foramina stylomastoideum: a cadaveric study

Abstract

Surgical robots have been widely used in surgery. Currently, the da Vinci Surgical System (Intuitive Surgery, Inc., Sunnyvale, CA, USA) is the most common robotic system used in the clinical setting. This system has proven useful for lesions in occult positions, such as tumors at the base of the tongue, ranulas, and submandibular lithiases. It is less traumatic compared to traditional open surgical procedures; however, its suitability for punctures remains debatable. Remebot (Beijing Baihui Weikang Technology Co., Ltd.; Beijing, China) is a surgical robot that is currently being used for neurosurgical procedures. Based on the intra-operational navigation, it can aid the surgeon with both the direction and depth of puncture, simultaneously. Although it can reportedly achieve an accuracy of 1.330 ± 0.566 mm[1] in biopsy operations, the same has not been reported in the field of oral and maxillofacial surgery. Therefore, in order to verify the feasibility of using a robot in oral and maxillofacial surgery, we chose to puncture the foramen ovale (FO) and foramina stylomastoideum (FS) in the present study. The FO is located in the large wing (near the body) of the sphenoid bone, in front of the spinous foramen, and posterolateral to the foramen rotundum. The mandibular nerve exits the FO and enters the infratemporal fossa. In the clinical setting, the treatment of trigeminal neuralgia often involves a percutaneous puncture of the FO. However, it is difficult to successfully puncture the FO in a single attempt because of its location deep within the human body; moreover, the puncture path faces obstruction from the upper and lower jaws, thereby reducing the actual effective puncture angle. The FS is located on the lateral side of the skull base, between the styloid process and the mastoid process of the temporal bone and behind the root of the styloid process. It acts as the external opening of the facial nerve canal and extends vertically upward to join with the canal. Adenoid cystic carcinoma of the parotid gland can easily develop inside the FS along the facial nerve owing to its neurophilic and fast-growing nature. However, it is sensitive to radiotherapy; brachytherapy seeds implanted into the FS can control tumor progression. Only a few studies have reported the use of a robotic system in the maxillofacial region. Thus, this study aimed to verify the accuracy and feasibility of the application of Remebot in the field of oral and maxillofacial surgery by puncturing the FO and FS. The following materials were used in this study: Remebot, Kirschner wire, and 11 cadaveric heads fixed in 10% buffered formalin. All specimens were from voluntary donation and obtained by Department of Anatomy of Peking Union Medical College. The study protocol was approved by the Institutional Review Board of General Hospital of the People Liberation Army (No. S2018-281-02). The surface of each cadaveric head was cleaned before the surgery. Three fiducial markers containing ceramic balls were pasted onto the frontal and bilateral temporal regions of a cadaveric head. Owing to difficulties in pasting the markers, bone nail markers were used for the remaining specimens. It is important to note that the three points should not be collinear and four points should not be coplanar while placing the markers. The specimen was placed in a supine position. Subsequently, pre-operative volumetric thin-layer computed tomography (CT) scanning of the cadaveric head was performed. Each head was placed in a holder to fix its spatial position. Digital Imaging and Communications in Medicine data were imported to the Remebot-dedicated software and reconstructed. The FO and FS were identified on the base of the skull. The trajectories for bilateral percutaneous puncture of the FO and FS were planned on different views using 3D reconstructed objects. The Hartel anterior approach was used as a reference to design the pathway for the percutaneous puncture of the FO. After th