SpaceOAR Hydrogel
SpaceOAR creates temporary separation between the prostate and anterior rectal wall to reduce rectal radiation exposure during prostate radiotherapy. SpaceOAR Vue is an iodinated PEG formulation designed for radiographic visibility, including CT. Its CT appearance differs from that of the original noniodinated hydrogel.[1][2]
The February 2026 FDA 510(k) clearance of Vue (K260119) covers limited component changes with indications for use identical to the earlier device.[1]
Persistence and Imaging
Manufacturer safety information describes spacing for approximately 12 weeks and absorption around six months, while explicitly noting that complete absorption may take longer. The product, placement date, symptoms and imaging findings are reviewed together.[3]
Evidence
A phase III trial randomized 222 men receiving conventionally fractionated image-guided IMRT. Patients were randomized 2:1 to spacer or control and received 79.2 Gy in 1.8-Gy fractions. At a median follow-up of three years, rectal toxicity and bowel quality of life favored the spacer.[4] These results apply to that regimen. A 2025 systematic review of 30 prospective studies reported improved long-term bowel quality of life with implantable spacers and no grade 4 or 5 gastrointestinal toxicity in clinical trials.[6]
Placement Injury and Reconstructive Relevance
The spacer is placed transperineally under ultrasound guidance. It can cause serious injury if injected into the rectal wall, another unintended tissue plane or a blood vessel. The manufacturer's 2022 safety update directs the operator to maintain needle-tip visualization, aspirate before injection, stop if blood is aspirated, and stop immediately if hydrogel is not seen entering the intended perirectal space. Continued injection into an uncertain plane can cause serious harm, including embolism.[5]
Reported risks include infection or abscess, rectal ulceration, perforation, fistula, necrosis and embolism. Prior pelvic radiotherapy may increase fistula risk. The manufacturer states that patients with PEG sensitivity, and for Vue sensitivity to its iodine-containing material, have not been studied.[3]
A review of the FDA MAUDE database identified 22 unique reports covering 25 patients between January 2015 and March 2019, an increasing count each year over that window. Reported major complications included acute pulmonary embolism, severe anaphylaxis, prostatic abscess and sepsis, purulent perineal drainage, rectal wall erosion and rectourethral fistula.[7]
Spacer history is relevant when evaluating pain, bleeding, infection, new urinary or rectal symptoms or a suspected post-radiation fistula. See Radiation Tissue Effects and Rectovesical Fistula.
References
1. FDA. SpaceOAR Vue System, K260119. February 10, 2026. Clearance, indications and device summary.
2. Boston Scientific. SpaceOAR Vue System Hydrogel Spacers. Current device description, accessed September 12, 2026. Manufacturer product information.
3. Boston Scientific. SpaceOAR Hydrogel Important Safety Information. Accessed September 12, 2026. Manufacturer safety information.
4. Hamstra DA, Mariados N, Sylvester J, et al. Continued Benefit to Rectal Separation for Prostate Radiation Therapy: Final Results of a Phase III Trial. Int J Radiat Oncol Biol Phys. 2017;97:976–985. doi:10.1016/j.ijrobp.2016.12.024.
5. Boston Scientific. Urgent Field Safety Notice: SpaceOAR and SpaceOAR Vue IFU Update. February 24, 2022, including Appendix 1. Manufacturer notice hosted by Swissmedic.
6. Lippens J, Willems L, Boychak O, et al. Implantable Rectal Spacers in Prostate Cancer Radiation Therapy: A Systematic Review. Pract Radiat Oncol. 2025;15(5):e460-e483. doi:10.1016/j.prro.2025.03.009
7. Aminsharifi A, Kotamarti S, Silver D, Schulman A. Major Complications and Adverse Events Related to the Injection of the SpaceOAR Hydrogel System Before Radiotherapy for Prostate Cancer: Review of the Manufacturer and User Facility Device Experience Database. J Endourol. 2019;33(10):868-871. doi:10.1089/end.2019.0431