MRI of spermatic cord lesions: a practical pattern-based approach

Spermatic cord lesions are rare and may present as inguinal or paratesticular masses, sometimes extending along the inguinal canal or retroperitoneal pathway. Ultrasonography is usually the first-line imaging modality for scrotal and paratesticular abnormalities; however, MRI provides additional information regarding lesion localization, tissue composition, disease extent, and features suggestive of malignancy. In this review article, we review the anatomy and constituent structures of the spermatic cord and illustrate the MRI findings of selected benign, inflammatory, vascular, and malignant conditions. We propose a practical three-step MRI-based diagnostic approach that first establishes the lesion's anatomic origin and relationship to the spermatic cord, then classifies it according to MRI pattern findings, and finally integrates these findings to narrow the differential diagnosis. These patterns include cystic/fluid-filled, tubular/ductal, serpiginous venous, fibrous, fat-containing, and predominantly solid lesions. This approach is intended to help radiologists distinguish true spermatic cord lesions from adjacent paratesticular mimics, narrow the differential diagnosis, and identify findings relevant to clinical management. Ultrasonography remains the first-line examination, with MRI serving primarily as a problem-solving modality when localization, characterization, or assessment of extent remains uncertain. The proposed categories are intended as overlapping pattern descriptors rather than mutually exclusive diagnostic entities.