Noninvasive Differentiation of Obstructive Azoospermia and Nonobstructive Azoospermia Using Multimodel Diffusion...

Area of Science:

• Radiology
• Urology
• Medical Imaging

Background:

• Azoospermia, characterized by absent sperm in ejaculate, requires differentiation between obstructive (OA) and nonobstructive (NOA) causes.
• Current diagnostic methods for azoospermia can be invasive, necessitating the development of noninvasive techniques.
• Multimodal diffusion-weighted imaging (DWI) offers advanced tissue characterization beyond conventional MRI.

Purpose of the Study:

• To evaluate the diagnostic performance of various DWI-derived parameters in differentiating OA from NOA.
• To assess the utility of parameters from monoexponential, stretched-exponential DWI, and diffusion kurtosis imaging (DKI).
• To identify novel imaging biomarkers for noninvasive azoospermia diagnosis.

Main Methods:

• Prospective enrollment of 46 azoospermia patients (21 OA, 25 NOA).
• Acquisition of multimodal DWI parameters: apparent diffusion coefficient (ADC), distributed diffusion coefficient (DDC), diffusion heterogeneity (α), diffusion kurtosis diffusivity (D_app), and diffusion kurtosis coefficient (K_app).
• Receiver operating characteristic (ROC) analysis to evaluate diagnostic performance and area under the curve (AUC) for each parameter.

Main Results:

• All evaluated DWI parameters (ADC, α, DDC, D_app, K_app) showed significant differences between OA and NOA groups (P < 0.001).
• K_app exhibited the highest AUC (0.965) for differentiating OA from NOA, followed by DDC (0.946), D_app (0.933), ADC (0.922), and α (0.887).
• K_app demonstrated significantly higher diagnostic accuracy compared to the conventional ADC (P < 0.05).

Conclusions:

• Multimodal DWI parameters show significant potential for noninvasive differentiation of obstructive and nonobstructive azoospermia.
• The K_app parameter derived from DKI modeling is a promising imaging biomarker for distinguishing azoospermia types.
• These findings support the integration of advanced DWI techniques into the diagnostic workup of azoospermia.