CT and MRI features of extratesticular scrotal masses in children

Objective: To evaluate the imaging features of extratesticular scrotal masses in children. Methods: Imaging findings and clinical records were retrospectively analyzed in 10 children with extratesticular scrotal masses confirmed by surgery and pathology. Results: Benign lesions (7) included 2 fibrous hamartomas of infancy, 1 ectopic spleen tissue, 1 vascular malformation, 1 venous hemangioma, 1 abscess, and 1 cyst whereas malignancy was rhabdomyosarcoma in 3 children. All presented as painless scrotal masses with non-specific laboratory examinations. On CT and MRI, fibrous hamartoma of infancy appeared as heterogeneous scrotal masses near the inguinal canals with mild to moderate enhancement. The ectopic spleen tissue was a round, well-circumscribed nodule with intense homogeneous contrast enhancement superior to the left testis. Vascular malformation was seen as a mass with irregular shape under the tunica vaginalis with some flow voids on T₂-weighted imaging and early intense contrast enhancement. Venous hemangioma with thrombus formation exhibited a round well-defined mass with soft tissue density located above the testis and medial side of sperm cord, majority of which did not enhance. Abscess was a round heterogeneously hyperintense lesion on T₂- and diffusion-weighted imaging with ill-defined margins in the midline of the scrotum. Cyst showed typical round lesion with fluid density and no enhancement. Rhabdomyosarcomas demonstrated as heterogeneous markedly enhancing paratesticular masses, one of which invaded the testis and associated with distant metastasis. Conclusion: Most extratesticular scrotal lesions in children are benign, some of which have characteristic imaging appearance. Preoperative assessment with ultrasound and MRI is recommended. (authors)