The anatomy and pathology of the space of Retzius

The space of Retzius is an important anatomic location for pathology. Pathology in the space of Retzius is more common than previously believed, especially as more cases are discovered with increased use of cross-sectional imaging. Knowledge of the anatomy of the Space of Retzius is crucial for identifying and distinguishing between benign and pathological findings. This paper uses several case examples to discuss benign etiologies, including normal tissue or a foreign body. The paper also demonstrates a case series with pathologic findings in the Space of Retzius under the broad categories of infection, neoplasm, hemorrhage, or urine extravasation. Understanding of the anatomy and these example cases can improve the diagnostic accuracy of radiologists.