Magnetic resonance imaging for intratesticular and extratesticular scrotal lesions

To evaluate magnetic resonance imaging (MRI) utility in intratesticular and extratesticular scrotal diseases.

Two radiologists retrospectively reviewed images of patients who underwent ultrasound followed by MRI, categorizing them as intratesticular or extratesticular and malignant, benign, indeterminate, or inadequate study. For patients who underwent surgical excision, pathologic results were also correlated to the presurgical ultrasound and MRI diagnoses.

Of 69 cases, 38 were intratesticular lesions and 31 were extratesticular lesions. MRI and ultrasound diagnoses were discordant in 21 (55.32%) intratesticular and 19 (61.3%) extratesticular lesions. MRI diagnosis was malignant after an indeterminate ultrasound in 0 and 4 (12.9%) intratesticular and extratesticular lesions, respectively. MRI diagnosis was benign after an indeterminate ultrasound in 18 (47.43%) and 14 (45.2%) intratesticular and extratesticular lesions, respectively. A malignant ultrasound diagnosis was reversed to benign MRI diagnosis in one (2.6%) intratesticular and one (3.2%) extratesticular lesion. In no case was a benign lesion on ultrasound read as malignant on MRI in either group. The cohort of patients with intratesticular lesions received a mean clinical and radiographic follow up of 2.49 ± 1.97 and 1.85 ± 1.46 years, respectively. The patients with extratesticular lesions received a mean clinical and radiographic follow up of 1.30 ± 1.08 and 2.00 ± 1.28 years, respectively. In no case did repeat imaging change the diagnosis after initial MRI and ultrasound evaluation.

MRI was effective at characterizing both intratesticular and extratesticular lesions in the majority of cases.