Ultrasonographically determined size of seminiferous tubules predicts sperm retrieval by microdissection testicular sperm extraction in men with nonobstructive azoospermia.

Objective: To investigate the value of the ultrasonographically determined size of seminiferous tubules and other conventional parameters for predicting sperm retrieval by microdissection testicular sperm extraction (micro-TESE).

Design: Clinical retrospective study.

Setting: Two urological clinics.

Patient(s): Eight hundred six men with nonobstructive azoospermia.

Intervention(s): Micro-TESE.

Main Outcome Measure(s): Sperm retrieval.

Result(s): Sperm retrieval was successful in 240 (29.8%) of the 806 men. In a receiver operating characteristic analysis of sperm retrieval, the area under the curve (AUC) for seminiferous tubules, assessed as 0, 100, 200, 250, or 300 μm, was no less than 0.82 (95% confidence interval [CI] 0.79-0.85). Sensitivity and specificity at a cutoff point of 250 μm were 76.7% and 80.7%, respectively. An AUC of 0.85 (95% CI, 0.81-0.88) was attained in a parsimonious multiple logistic regression model that included age (<30, 30-39, and 40-59 years), low follicle-stimulating hormone (<14 IU/L), history of cryptorchidism, and sex chromosome abnormality in addition to the diameter of seminiferous tubules.

Conclusion(s): The gray-scale image in testicular ultrasound was shown to be highly predictive of sperm retrieval in micro-TESE in a large series of men with nonobstructive azoospermia.