Saxton H M, Borzyskowski M, Mundy A R, Vivian G C
Department of Radiology, Guy's Hospital, London, England.
Radiology. 1988 Jul;168(1):147-50. doi: 10.1148/radiology.168.1.3380951.
Spinning top urethra (STU) is a term used to describe a widened posterior urethra seen mainly in girls. It is commonly regarded as a normal variant. The authors studied 30 girls with STU using videourodynamics. Twenty-eight showed bladder instability; 21, a congenital wide bladder neck anomaly; and 20, both instability and a wide bladder neck. One patient had a sensitive bladder. All patients had a urodynamic abnormality. The authors believe that the STU is nearly always an indication of bladder instability or wide bladder neck anomaly. The most common mechanism for the dilatation of the posterior urethra is that unstable contractions are resisted by a voluntary increase in distal sphincter tension so as to prevent leakage of urine. The resulting pressure rise produces distention of the posterior urethra, which will be maximal in subjects with a weak bladder neck mechanism as in the congenital wide bladder neck anomaly. The authors believe that STU is seldom if ever a normal variant.
陀螺状尿道（STU）是一个用于描述主要在女孩中出现的后尿道增宽的术语。它通常被视为一种正常变异。作者使用视频尿动力学对30名患有STU的女孩进行了研究。28名表现出膀胱不稳定；21名存在先天性膀胱颈宽大异常；20名既有不稳定又有膀胱颈宽大。1名患者有敏感膀胱。所有患者都存在尿动力学异常。作者认为STU几乎总是膀胱不稳定或膀胱颈宽大异常的一种表现。后尿道扩张的最常见机制是不稳定收缩受到远端括约肌张力的自愿增加的抵抗，以防止尿液泄漏。由此产生的压力升高导致后尿道扩张，在膀胱颈机制薄弱的受试者中，如先天性膀胱颈宽大异常患者，这种扩张将最为明显。作者认为STU极少是正常变异。
