Value of MRI in the Evaluation of Azoospermia

Abstract

Abstract Background Azoospermia is defined as the absence of spermatozoa in the ejaculate and is present in about 10%–20% of infertile men. It is classified as obstructive azoospermia (OA) or nonobstructive azoospermia (NOA). OA is caused by obstruction of sperm delivery route at any level (rete testis, efferent ducts, epididymis, vas deferens, and ejaculatory duct). NOA is caused by testicular failure to produce sperm due to various factors. Aim of the Study In the current study we aimed to show the usefulness of magnetic resonance imaging (MRI) in the evaluation of infertile men and its ability to distinguish obstructive from nonobstructive azoospermia. Patients and Methods We included 20 azoospermic men (8 with OA & 10 with NOA), diagnosed after at least two semen analyses & confirmed by testicular biopsy, MRI was done to each patient with same protocol with measurement of both volume & ADC value for every testis. Results Our study revealed that Patients with NOA usually have atrophic testicles with high ADC values, whereas patients with OA have testicles of normal size with low ADC values based on testicular volume & ADC values, using a cutoff of ≥ 13.17 ml & ≤1.05 ×10-3 mm2/s respectively, we were able to make a diagnosis of OA with a sensitivity of 100% and specificity of 83%. Also we find that abnormalities typical for the obstruction of the seminal tract (e.g., prostatic cysts, the absence of vas deferens, dilatation of ejaculatory ducts or vasa deferentia) are found in patients with OA which may be amenable to surgical correction. Conclusion On the basis of our preliminary data, TV and ADC might represent useful MRI parameters in the workup of patients with NOA by helping to predict the presence of spermatozoa after mTESE.