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Illustration of SpaceOAR Hydrogel.

SpaceOAR™ Hydrogel


SpaceOAR Hydrogel evidence summary

Creating more space between the prostate and rectum can result in a significant reduction in rectal radiation.¹ This reduction in rectal radiation can help reduce late rectal toxicity, which can improve quality of life.²

US Pivotal Trial. 73% less rectal radiation, 75% less rectal toxicity, better quality of life infographic.

SpaceOAR™ Hydrogel is associated with lower rectal toxicity and higher bowel quality of life in long-term follow-up³

Systematic review & meta-analysis

SpaceOAR Hydrogel has been shown to help minimize side effects²ʼ⁴


Relative reduction in rectal V701


Late grade 2+ rectal toxicity2


Reduced declines in bowel quality of life2


Reduced likelihood of decline in urinary quality of life2


Reported erections sufficient for intercourse4

Real-world data shows how different treatment approaches can utilize SpaceOAR Hydrogel

Early Tolerance and Tumor Control Outcomes with High-Dose Ultrahypofractionated Radiation Therapy for Prostate Cancer

Zelefsky MJ, Pinitpatcharalert A, Kollmeier M, et al.

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A Multi-Institutional Phase 2 Trial of High-Dose SAbR for Prostate Cancer Using Rectal Spacer

Folkert MC, Zelefsky MJ, Hannan R, et al.

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Dosimetric Feasibility of Neurovascular Bundle-Sparing Stereotactic Body Radiotherapy with Periprostatic Hydrogel Spacer for Localized Prostate Cancer to Preserve Erectile Function

Hwang ME, Mayeda M, Shaish H, et al.

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Expanding the Utilization of Rectal Spacer Hydrogel for Larger Prostate Glands (>80cc): Feasibility and Dosimetric Outcomes

Fagundes M, Rodrigues MA, Olszewski S, et al. 

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Rectal Hydrogel Spacer Improves Late Gastrointestinal Toxicity Compared to Rectal Balloon Immobilization After Proton Beam Radiotherapy for Localized Prostate Cancer: A Retrospective Observational Study

Dinh TT, Lee HJ, Macomber MW, et al.

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SpaceOAR Vue™ Hydrogel: The Next-Generation Radiopaque Hydrogel Spacer

Brenneman RJ, Baumann BC

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SpaceOAR Hydrogel Spacer Injection Prior to Stereotactic Body Radiation Therapy for Men with Localized Prostate Cancer

Payne HA, Pinkawa M, Peedell Cl, et al.

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Hydrogel Spacer Distribution Within the Perirectal Space in Patients Undergoing Radiotherapy for Prostate Cancer: Impact of Spacer Symmetry on Rectal Dose Reduction and the Clinical Consequences of Hydrogel Infiltration into the Rectal Wall

Benjamin W. Fischer-Valuck, MD; Anupama Chundury, MD; Hiram Gay, MD; Walter Bosch, DSC; Jeff Michalski MD, MBA

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Role for Rectal Spacer in the Radiotherapeutic Management of Prostate Cancer video screenshot.

Michael J. Zelefsky, MD, presents the Role for Rectal Spacer in the Radiotherapeutic Management of Prostate Cancer on Grand Rounds in Urology

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  1. Mariados N, Sylvester J, Shah D, et al. Hydrogel spacer prospective multicenter randomized controlled pivotal trial: dosimetric and clinical effects of perirectal  spacer application in men undergoing prostate image guided intensity modulated radiation therapy. Int J Radiat Oncol Biol Phys. 2015 Aug 1;92(5):971–7.
  2. 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 Apr 1;97(5):976–85.
  3. Miller LE, Efstathiou JA, Bhattacharyya SK, et al. Association of the placement of a perirectal hydrogel spacer with the clinical outcomes of men receiving radiotherapy for prostate cancer: a systematic review and meta-analysis. JAMA Netw Open. 2020 Jun;3(6):e208221.
  4. Hamstra DA, Mariados N, Sylvester J, et al. Sexual quality of life following prostate intensity modulated radiation therapy (IMRT) with a rectal/prostate spacer: Secondary analysis of a phase 3 trial. Pract Radiat Oncol. 2018;8(1):e7–e15.

Caution: U.S. Federal law restricts this device to sale by or on the order of a physician.

CAUTION: The law restricts these devices to sale by or on the order of a physician. Indications, contraindications, warnings, and instructions for use can be found in the product labelling supplied with each device or at Products shown for INFORMATION purposes only and may not be approved or for sale in certain countries. This material not intended for use in France.

SpaceOAR and SpaceOAR Vue Hydrogels are intended to temporarily position the anterior rectal wall away from the prostate during radiotherapy for prostate cancer and in creating this space it is the intent of SpaceOAR and SpaceOAR Vue Hydrogels to reduce the radiation dose delivered to the anterior rectum.

SpaceOAR and SpaceOAR Vue Hydrogels contain polyethylene glycol (PEG). SpaceOAR Vue Hydrogel contains iodine.

Prior to using these devices, please review the Instructions for Use for a complete listing of indications, contraindications, warnings, precautions and potential adverse events.

As with any medical treatment, there are some risks involved with the use of SpaceOAR and SpaceOAR Vue Hydrogels. Potential complications associated with SpaceOAR and SpaceOAR Vue Hydrogels include, but are not limited to: pain associated with SpaceOAR and SpaceOAR Vue Hydrogels injection, pain or discomfort associated with SpaceOAR and SpaceOAR Vue Hydrogels, local inflammatory reactions, infection (including abscess), urinary retention, urgency, constipation (acute, chronic, or secondary to outlet perforation), rectal tenesmus/muscle spasm, mucosal damage, ulcers, fistula, perforation (including prostate, bladder, urethra, rectum), necrosis, allergic reaction (localized or more severe reaction, such as anaphylaxis), embolism (venous or arterial embolism is possible and may present outside of the pelvis, potentially impacting vital organs or extremities), syncope and bleeding. The occurrence of one or more of these complications may require treatment or surgical intervention. URO-989811-AB.

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