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Simple Summary: This single-center, single-arm, phase II trial aimed to propose a safe and effective salvage spine SBRT regimen for patients with spinal metastases. The second SBRT dose consisted of 30 Gy delivered in five fractions with specific dose constraints for the spinal cord and nerve plexuses. Among the enrolled patients, 12 received the second SBRT at the same spinal level, while 8 received it at an adjacent level. No instances of radiation myelopathy or local failure were observed during the follow-up period. However, grade 3 late adverse effects (including lumbosacral plexopathy and vertebral compression fractures) were observed in 25% of patients throughout the entire follow-up period, suggesting that the second SBRT poses a risk of toxicity. Purpose: The optimal method for the second course of stereotactic body radiotherapy (SBRT) for spinal metastases remains poorly established. This single-center, single-arm, phase II trial was conducted to propose a safe and effective salvage spine SBRT. Methods: The patients initially treated with SBRT for spine-targeted protocol treatment, or for areas adjacent to the spine, were enrolled. The second SBRT dose was 30 Gy delivered in five fractions; the spinal cord dose constraint was 15.5 Gy at the maximum point dose. The brachial or lumbosacral plexuses were dose-constrained to <30 Gy if the boundary between the nerves and tumors was detected. The primary endpoint was dose-limiting toxicity (DLT) (grade ≥ 3 severe radiation-related toxicity) within a year after the second SBRT. Results: The second SBRT was administered to the same spinal level in 12 patients and to an adjacent spinal level in 8 patients. SBRT2 was performed for 14 painful lesions, 10 MESCC, and 6 oligometastases, with some lesions having multiple indications. The median interval between SBRT sessions was 21 months (range: 6–51 months). The median follow-up duration was 14 months. No radiation myelopathy or local failure was reported during the follow-up period. DLT was confirmed in two patients (10%) within a year, both of whom developed grade 3 lumbosacral plexopathy. These two patients received SBRT twice to the S1–2 and S1–5 vertebrae, respectively, and both experienced paralysis of the tibialis anterior muscle (L5 level). Grade 3 late adverse effects (including lumbosacral plexopathy and vertebral compression fracture) were observed in 25% of the patients throughout the entire follow-up period. Conclusions: The second spine SBRT achieved good local control without causing myelopathy. However, one-quarter of the patients experienced grade 3 late adverse effects, suggesting that the treatment protocol carries a risk of toxicity. [ABSTRACT FROM AUTHOR]

Large area inspection using a robot is critical in a disastrous situation; especially when humans are inhabiting the catastrophic environment. Unlike natural environments, such environments lack details. Thus, creating 3D maps and identifying objects has became a challenge. This research suggests a 3D Point Cloud Data (PCD) merging algorithm for the less textured environment, aiming World Robot Summit Standard Disaster Robotics Challenge 2021 (WRS). Spider2020, a robotic system designed by the Robot Engineering Laboratory, University of Aizu, was used in this research. Detecting QR codes in a wall and merging PCD, and generating a wall map are the two main tasks in the competition. The Zxing library was used to detect and decode QR codes, and the results were quite accurate. Since the 3D mapping environment has fewer textures, decoded QR code locations are used as the PCD mapping markers. The position of the PCD file was taken from the location given by the robotic arm in Spider2020. The accuracy of merging PCD was improved by including the position of PCD files in the merging algorithm. The robotic system can be used for Large area Inspections in a disastrous situation.

Standard Disaster Robotics Challenge of World Robot Summit (WRS) aims to test the ability of robots that can be used as disaster response robots. Robot Engineering Lab of the University of Aizu is developing a robotic system to address challenges in the WRS. The competition has five stages, and the teleoperation robotic system had to be developed to satisfy the requirements of each challenge. REL uses a disaster-response robot called Giraffe, which has the capability of traveling in hard terrain. Open Robot Technology Middleware uses to integrate all of the subsystems inside the robot. Each subsystem has different tasks that process video data, RGB depth data, Point Cloud Data, sensor data and, feedback data. The Robotic system includes 6 cameras and NDI Software Developer Kit used to transmit and view video streams remotely. The video stream from each camera can be viewed separately, and it gives wider control over the robot for the operator. The teleoperation robotic system was tested during a robot demonstration held in Fukushima Robot Test Field, and results were analyzed according to the WRS 2018 competition guidelines. The results were at an acceptable level.

Most studies of vertebral compression fractures (VCF) caused by stereotactic body radiotherapy (SBRT) do not discuss the symptoms of this complication. In this paper, we aimed to determine the rate and prognostic factors of painful VCF caused by SBRT for spinal metastases. Spinal segments with VCF in patients treated with spine SBRT between 2013 and 2021 were retrospectively reviewed. The primary endpoint was the rate of painful VCF (grades 2–3). Patient demographic and clinical characteristics were evaluated as prognosticators. In total, 779 spinal segments in 391 patients were analyzed. The median follow-up after SBRT was 18 (range: 1–107) months. Sixty iatrogenic VCFs (7.7%) were identified. The rate of painful VCF was 2.4% (19/779). Eight (1.0%) VCFs required surgery for internal fixation or spinal canal decompression. The painful VCF rate was significantly higher in patients with no posterolateral tumor involvement than in those with bilateral or unilateral involvement (50% vs. 23%; p = 0.042); it was also higher in patients with spine without fixation than in those with fixation (44% vs. 0%; p < 0.001). Painful VCFs were confirmed in only 2.4% of all the irradiated spinal segments. The absence of posterolateral tumor involvement and no fixation was significantly associated with painful VCF. [ABSTRACT FROM AUTHOR]

This prospective phase I trial aimed to determine the recommended dose of 3‐day total marrow and lymphoid irradiation (TMLI) for a myeloablative conditioning regimen by increasing the dose per fraction. The primary end‐point of this single‐institution dose escalation study was the recommended TMLI dose based on the frequency of dose‐limiting toxicity (DLT) ≤100 days posthematopoietic stem cell transplantation (HSCT); a 3 + 3 design was used to evaluate the safety of TMLI. Three dose levels of TMLI (14/16/18 Gy in six fractions over 3 days) were set. The treatment protocol began at 14 Gy. Dose‐limiting toxicities were defined as grade 3 or 4 nonhematological toxicities. Nine patients, with a median age of 42 years (range, 35–48), eight with acute lymphoblastic leukemia and one with chronic myeloblastic leukemia, received TMLI followed by unrelated bone marrow transplant. The median follow‐up period after HSCT was 575 days (range, 253–1037). Three patients were enrolled for each dose level. No patient showed DLT within 100 days of HSCT. The recommended dose of 3‐day TMLI was 18 Gy in six fractions. All patients achieved neutrophil engraftment at a median of 19 days (range, 14–25). One‐year overall and disease‐free survival rates were 83.3% and 57.1%, respectively. Three patients experienced relapse, and no nonrelapse mortality was documented during the observation period. One patient died due to disease relapse 306 days post‐HSCT. The recommended dose of 3‐day TMLI was 18 Gy in six fractions. The efficacy evaluation of this regimen is currently being planned in a phase II study. [ABSTRACT FROM AUTHOR]