Multiple sequences MRI in diagnosis of non-palpable undescended testis

Abstract

Objective To evaluate the role of multiple sequences MRI in diagnosis and preoperative evaluation of non-palpable undescended testis. Methods 58 patients with unilateral or bilateral non-palpable undescended testis underwent abdominal and pelvic MRI 2 weeks before surgery. Multiple sequences MRI included diffusion-weighted imaging(DWI)with b values of 400 and 800 s/mm2, T1 and T2-weighted sequence, and T2-weighted fat-suppressed sequence. Preoperative images including the conventional MRI images, DWI images, and the conventional-MRI and DWI images together. ADC value was detected. Pathological findings were used as the gold standard to evaluate the diagnostic accuracy of multiple sequences MRI in detection of non-palpable undescended testis and its differential diagnosis with lymph nodes. Results The combination of DWI and conventional MRI was the most sensitive method in detection of non-palpable undescended testis, with the sensitivity, specificity and accuracy of 96.5%, 87.5%, and 95.3%, respectively. Malignant non-palpable undescended testes were all detected. The ADC value of the non-palpable undescended testis, lymph nodes and malignant non-palpable undescended testis was(1.18±0.17)×10-3 mm2/s, (1.49±0.27)×10-3 mm2/s, and(0.84±0.20)×10-3 mm2/s, respectively. The difference had statistical significance(P<0.05). Conclusion Multiple sequences MRI improves the diagnostic accuracy of non-palpable undescended testis, which can be routinely used in preoperative evaluation of non-palpable undescended testis. Key words: Non-palpable undescended testis; Magnetic resonance imaging; Diffusion weighted imaging; Malignant; Lymph node