Abdominal Radiology

, Volume 44, Issue 1, pp 247–251 | Cite as

MRI findings of absorbable hydrogel spacer for prostate cancer therapy: a pictorial review

  • Aaron RohrEmail author
  • Kyle Werth
  • Xinglei Shen
  • Zachary Collins
  • Shelby Fishback
  • Jill Jones
  • Ryan Ash
  • Vanessa Williams
Pictorial essay


Prior studies have shown that dose-escalated radiation therapy for prostate cancer improves clinical outcomes. However, this is associated with increased rectal toxicity. Hydrogel spacer for prostate cancer therapy is an effective way of decreasing rectal toxicity in the late post-therapeutic stages. In some occasions, the gel spacer may not be placed symmetrically between the rectum and prostate. There are several forms of a malpositioned spacer, including lateral displacement, rectal wall infiltration, and prostate capsule infiltration. This manuscript is aimed at evaluating appropriately positioned and malpositioned gel spacers, primarily via magnetic resonance imaging. There are limited educational imaging guides that address what radiologists should evaluate on post-spacer placement imaging. This pictorial review will specifically evaluate post-injection pitfalls such as asymmetry, rectal wall infiltration, and subcapsular injection.


Prostate spacer Gel MRI Asymmetry 


Compliance with ethical standards


This study contains no funding.

Conflict of interest

Aaron Rohr declares that he has no conflict of interest. Kyle Werth declares that he has no conflict of interest. Xinglei Shen declares that he has no conflict of interest. Zachary Collins declares that he has no conflict of interest. Shelby Fishback declares that she has no conflict of interest. Jill Jones declares that she has no conflict of interest. Ryan Ash declares that he has no conflict of interest. Vanessa Williams declares that she has no conflict of interest.

Ethical approval

This article does not contain any studies with human participants performed by any of the authors.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • Aaron Rohr
    • 1
    Email author
  • Kyle Werth
    • 2
  • Xinglei Shen
    • 3
  • Zachary Collins
    • 2
  • Shelby Fishback
    • 2
  • Jill Jones
    • 2
  • Ryan Ash
    • 2
  • Vanessa Williams
    • 2
  1. 1.Department of Interventional RadiologyUniversity of StanfordStanfordUSA
  2. 2.Department of RadiologyUniversity of Kansas Health SystemsKansas CityUSA
  3. 3.Department of Radiation OncologyUniversity of Kansas Health SystemsKansas CityUSA

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