Role of Diffusion-Weighted Magnetic Resonance Imaging in Detection of Non-Palpable Undescended Testes.

Abstract

Objective:To evaluate the role of diffusion weighted MRI in the detection of non-palpable undescended testes. Materials and methods: Twenty nine boys with undescended testes underwent abdominal and pelvic MRI to identify the location of the testes. MRI was performed using the following sequences: T2-weighted half-Fourier single-shot turbo spin-echo (HASTE), 3-D gradient-echo T1-weighted, 2-D gradient-echo T1 in-phase and outof-phase, respiratory-triggered, turbo spin-echo T2-weighted sequence with fat saturation and free-breathing diffusion-weighted imaging (DWI) with b values of 50, 400, and 800 s/mm2. Results: In our study, we had 38 non-palpable undescended testicles detected in 29 patients. 17 testes were intracanalicular and 21 testes were intra-abdominal. All 17 intracanalicular testicles and 18 intraabdominal testicles were identified by preoperative conventional MRI and DWI. The sensitivity and specificity values for the MRI with addition of DWI versus laparoscopic findings were 94.6%, and 100% respectively. The overall prediction accuracy was 94.7%. Conclusion: DWI is easy to obtain and easy to evaluate in short time. DWI yields information that complements conventional MRI findings, improving identification and location of nonpalpable undescended testes. We recommend the use of DWI in addition to conventional MRI to increase the preoperative sensitivity and accuracy of identifying and locating nonpalpable testes. …………………………………………………………………………………………………….... Introduction:-Undescended testes is detected in about 1% of newly born boys, from which 80% are palpable clinically (1) and 20% non-palpable testes which cannot be detected by physical examination; being absent, atrophic or intraabdominal (2). About 18% of non palpable testes could be detected by physical examination under anesthesia, and 12.6% of viable testes could be discovered on exploration. They are usually detected distal to the inguinal canal and missed during physical examination (3).