Affiliation:
1. Department of Minimally Invasive Surgical and Medical Oncology Fukushima Medical University Fukushima City Fukushima Japan
2. Department of Radiology Southern Tohoku Proton Therapy Center Koriyama Fukushima Japan
3. Department of Radiation Physics and Technology Southern Tohoku General Hospital Koriyama Fukushima Japan
4. Division of Radiology, Faculty of Medicine Tohoku Medical and Pharmaceutical University Sendai Miyagi Japan
Abstract
ObjectiveTo evaluate the safety and complications of hydrogel spacer implantation.MethodsThis single‐center historical cohort study retrospectively analyzed cases of hydrogel spacer implantation between October 2018 and March 2022. The survey items were the rates of possible hydrogel injection implementation, the success rate of hydrogel implantation including asymmetry, higher position, rectal wall infiltration, subcapsular injection, and other adverse events, and width created by the spacer. To investigate the learning curve, 1, 2, and 3 points were assigned to adverse event grades G1, G2, and G3, respectively. Spacer effectiveness obstruction, such as asymmetry was assigned 3 points. A Mann–Whitney U test was performed to assess statistically significant differences.ResultsThe study included a total of 200 patients with a median (range) age of 70 (44–85) years. In 10 (5%) patients, hydrogel injection implementation was not possible. Of 190 patients who underwent hydrogel spacer placement, 168 (88%) received a satisfactory placement. The median (range) width of hydrogel spacers was 13.1 (4.4–18.7) mm. Spacer asymmetry, higher position, rectal wall infiltration, and prostate subcapsular infiltration occurred in 7 (3.7%), 5 (2.6%), 12 (6.3%), and 1 (0.5%) patients, respectively. G1 and G3 adverse events occurred in 13 (7%) and 4 (2%) patients, respectively. Practitioner #1 who performed the highest number of procedures had significantly (p = 0.04) lower total scores in group B.ConclusionSpacer implantation yielded favorable outcomes with a high percentage of appropriate spacer implantation, and few major complications.