英文: If this process were bilateral, then the problem would originate in the bladder trigone or urethra (or the prostate around the urethra) or some process (such as a large neoplasm) that could impinge on both ureters.

中文: 如果病变是双侧的，原因可能是膀胱三角或尿道前列腺部的病变；或是其它能侵犯两侧输尿管的病变（如大的肿瘤块）。       更详细...

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