Abstract: Objective · To assess the usefulness of contrast enhanced ultrasound (CEUS) in locating the testicular area to guide microdissection testicular sperm extraction (M-TESE) for patients with nonobstructive azoospermia (NOA).  Methods · CEUS was performed in 95 NOA patients. M-TESE was performed in the best and poorest perfusion areas on CEUS and in the conventional area. Sperm retrieval rates (SRR) of the three areas were compared.  Results · M-TESE was performed in 147 testicles (95 patients). SRRs in best perfusion area, poorest perfusion area and conventional area were 66.3%, 32.6% and 47.3% respectively, and the differences between groups were statistically significant (all P<0.05). The arriving time (AT), time to peak intensity (TTP), peak intensity (PI) and area under the curve (AUC) showed statistical significance (all P<0.05) between the successful retrieval group (94 points) and unsuccessful retrieval group (200 points). And the SRR showed statistical difference among the three pathological groups. In maturation arrest group and Sertoli cell only group, the SRR in the best perfusion area was higher than that in the conventional area (both P<0.05).  Conclusion · SRR was different in different pathological groups. The locating of the best perfusion area could guide M-TESE so as to improve the SRRs of maturation arrest group and Sertoli cell only group.

Key words:  contrast enhanced ultrasound, microdissection testicular sperm extraction, sperm retrieval rate, nonobstructive azoospermia