Comparison between O-arm Navigation and Conventional Fluoroscopic Guidance in Corrective Posterior Fixation for Cervical Spinal Injury.

Purpose : To compare the effectiveness of O-arm navigation with that of conventional fluoroscopic guidance in corrective posterior fixation for cervical spinal injury. Methods : This retrospective comparative study involved 11 consecutive patients who underwent corrective posterior fixation using O-arm navigation or conventional fluoroscopy for cervical spinal injury between February 2016 and May 2021. Patient-specific characteristics (age and sex), number of screws, number of pedicle screws, accuracy of pedicle screw insertion, number of vertebral bodies fixed, operating time, and length of hospital stay were analyzed using the t-test. A P-value < 0.05 was considered statistically significant. Results : Corrective posterior fixation was performed under O-arm navigation in 5 patients and under conventional fluoroscopic guidance in 6. A significantly greater number of pedicle screws was used in the O-arm group (6.4 vs 2.7, P = 0.046). According to the Neo classification for pedicle screw placement, there were no grade 2 or 3 breaches. No other items showed a significant difference between the groups (P > 0.05). Conclusion : O-arm navigation can improve the accuracy of cervical pedicle screw insertion. Its introduction could expand the indications for use of pedicle screws in posterior fixation of cervical spinal injury beyond those that are possible using conventional fluoroscopy. J. Med. Invest. 69 : 273-277, August, 2022.

Intuitive operability evaluation of surgical robot using brain activity measurement to determine immersive reality.

Surgical robots have improved considerably in recent years, but intuitive operability, which represents user inter-operability, has not been quantitatively evaluated. Therefore, for design of a robot with intuitive operability, we propose a method to measure brain activity to determine intuitive operability. The objective of this paper is to determine the master configuration against the monitor that allows users to perceive the manipulator as part of their own body. We assume that the master configuration produces an immersive reality experience for the user of putting his own arm into the monitor. In our experiments, as subjects controlled the hand controller to position the tip of the virtual slave manipulator on a target in a surgical simulator, we measured brain activity through brain-imaging devices. We performed our experiments for a variety of master manipulator configurations with the monitor position fixed. For all test subjects, we found that brain activity was stimulated significantly when the master manipulator was located behind the monitor. We conclude that this master configuration produces immersive reality through the body image, which is related to visual and somatic sense feedback.

Palliative surgery for malignant mediastinal tumor invading the superior vena cava and right atrium.

Intra-atrial extension of a superior vena cava (SVC) tumor is rare and it is associated with high mortality rates. An 80-year-old woman presented with malignant mediastinal tumor invading the superior vena cava and right atrium. The unresectable tumor caused uncontrolled SVC syndrome and led to the risk of pulmonary artery tumor thrombosis. Palliative surgery for the intracaval and atrial tumor was performed. Presently, 6 months after surgery, the patient remains free from SVC syndrome and has received effective adjuvant chemotherapy to reduce the size of the tumor.