OBJECTIVETo investigate the ultrasonographic features of epididymides in congenital obstructive azoospermia (COA) and acquired obstructive azoospermia (AOA).

METHODSA total of 211 infertile men with obstructive azoospermia were observed by scrotal ultrasonography, and the features of the epididymal ultrasonograms were compared between COA and AOA.

RESULTSCOA exhibited significantly higher rates of ectasia in the epididymal head, cord-like changes, abrupt tapering and absence of the epididymal body and tail than AOA (P < 0.05), while AOA showed markedly higher rates of epididymal body and tail duct ectasia and epididymal inflammatory mass than COA (P < 0.01). Tubular ectasia of the epididymal duct in the head, body and tail were markedly higher in the COA (14 [5.9%], 41 [17.2%] and 20 [8.4%] cases in 236 epididymides) than in the AOA (P < 0.05). Retiform ectasia were markedly higher in the AOA (119 [64.0%], 142 [76.3%] and 109 [58.6%] cases in 186 epididymides) than in the COA (P < 0.05), with statistically significant differences between the two groups (P < 0.05). Ultrasonographically, the epididymides of the COA patients were characterized by irregular ectasia of the epididymal tube with decreased and unclear wall echoes (P < 0.05), and those of the AOA patients by regular ectasia with enhanced wall echoes (P < 0.01).

CONCLUSIONThe ultrasonographic epididymal features of COA are obviously different from those of AOA, which is of important clinical application value for distinguishing the two conditions from each other.