【作者】 王洪一；

【导师】 李世荣；

【作者基本信息】 第三军医大学 ， 外科学， 2012， 博士

【摘要】 研究背景阴茎的长度在男性的生理及心理上都占有十分重要的地位，临床上各种原因引起的阴茎短小病例，甚至一部分阴茎尺寸正常的男性都希望通过一定的方式谋求阴茎增大。悬韧带松解术最初应用于先天性尿道上裂或膀胱外翻的矫正，随着对阴茎悬韧带及周围结构研究的深入，其手术适应症逐渐扩展至各种原因引起的先天性或后天性的阴茎短小（如阴茎发育不良、外伤缺损、阴茎癌切除术后等）。因其方法简单、对勃起功能影响小、术后恢复快等优点，最易被医生和患者所接受。在悬韧带松解阴茎延长术（简称为阴茎延长术）的临床应用中，最重要的两个问题是该手术的有效性及安全性。具体来说，即该手术的效果及该手术对阴茎勃起的影响。目前医学界对于该手术的效果尚存在较大的争议。一方面，该手术的确切效果尚未达成统一意见。普遍的观点认为该术式通常可以获得1~2cm的延长效果，但各文献报道的数据之间存在明显的差异，对于接受相同手术方式的同种病例，个体之间的延长效果差别较大。另一方面，该术式的术后患者满意程度普遍不高。因为通常该手术对与大部分患者的延长效果有限，但患者在接受手术前却往往对自身的手术效果有较高的期望。此外，临床上该手术的适应症较为混乱。Mondaini等报道，临床上谋求行该延长手术的男性中，大部分人的阴茎尺寸实际上在正常范围内。这些人对手术的期望普遍较高，该术式的平均延长效果很难令其满意，不能达到治疗目的。总之，许多研究者对该手术开展持保留的态度，认为该手术应避免过度开展，尤其对于阴茎尺寸接近或达到正常范围的男性。实际上，严格控制适应症并不能很好的改善术后患者满意度，关键的问题是使患者的期望与其实际能获得的效果相符合。因此，一个针对个体的手术效果的预测方法对于解决上述诸多争议将是非常有裨益的。精确的个体化预测必须掌握该手术对阴茎背根部结构的精确影响。然而，由于缺乏精确而有效的研究方法，目前研究对于该手术原理的认识还过于粗略，难以满足个体化预测的需要。因此，寻找一种能够揭示该手术对阴茎背根部结构的精确影响的研究方法，对于该手术深入研究和临床推广十分重要。阴茎延长术是以破坏阴茎背根部悬吊系统为代价而达到延长阴茎的目的，这不可避免的或多或少会影响悬吊系统的生理功能。阴茎背根部悬吊系统包括阴茎系韧带、悬韧带和耻骨弓状韧带。其主要生理功能是将阴茎体悬吊、固定于耻骨联合之下，并参与了维持阴茎“上举”的勃起状态。目前普遍的观点认为阴茎延长术对于阴茎勃起时的“稳定性”的影响不显著，但该观点尚未经过严格的实验加以证明，因此其正确性值得怀疑。实际上，传统的泌尿外科学领域对这种通俗意义上阴茎勃起“稳定性”并无针对性的研究，甚至对该概念都没有明确的定义。整形外科领域对阴茎延长术后所谓的阴茎勃起的“稳定性”的理解更倾向于阴茎勃起时是否出现明显的摆动或下垂。从该角度来说，我们认为阴茎勃起角度可以作为反映阴茎勃起“稳定性”的指标。遗憾的是，目前泌尿外科学及男科学相关专著及论著对于阴茎勃起角度的研究也十分有限。因此，为了研究阴茎延长术对阴茎勃起结构稳定性的影响，首先需要对阴茎勃起角度的形成机制及其与阴茎勃起结构稳定性的关系进行初步的研究。方法本研究分为三部分。1、我们选取了第三军医大学第西南医院整形美容科1988年至2011年行阴茎延长术的先天性阴茎发育不良病例322例，随机分为建模组（200例）与验证组（122例），将建模组手术前、后的常态与勃起状态阴茎长度等指标进行相关性和线性回归分析，拟揭示该手术前后阴茎长度的变化规律，并由此推导预测公式，通过建模组与验证组中预测结果与实际结果的一致性来评价预测效果。2、我们对3例先天性阴茎短小患者于手术前、后行阴茎背根部超声及MRI检查，对比两种检查结果，考察超声对阴茎背根部结构的显示情况，根据手术前后超声图像对比获得该手术对阴茎背根部结构的精确影响，并由此总结该手术的精确原理。3、我们从阴茎勃起角度形成的力学和结构因素出发，根据既往文献研究归纳了阴茎勃起角度的形成机制，并根据该机制及相关物理学原理建立了阴茎勃起角度的数学模型。最后通过新鲜尸体标本实验测量并计算相关参数。结果1、患者术后常态与勃起状态的延长长度、手术前后的阴茎勃起长度与常态长度的比值、术前常态长度与术前阴茎勃起长度与常态长度的比值存在显著的相关性（相关系数分别为0.921、0.803、-0.803，P＜0.01）。由此可推导出延长长度的预测公式，通过对建模组与验证组的数据进行检验，预测误差在±1.5cm以内时其有效预测率分别为84.5%和87.7%。2、超声检查可以显示阴茎背根部除悬韧带以外的主要结构的位置，包括阴茎海绵体、尿道海绵体、耻骨联合前下缘、阴茎背动脉等。手术后，被释放的固定段海绵体会有一个向下和沿长轴的位移，这段被释放的海绵体一部分仍隐藏域体内，另一部分则转化为游离段海绵体从而增加了游离段阴茎的长度。固定段海绵体的减少对常态延长长度的贡献约占1/4，被释放的海绵体沿长轴的伸长对常态延长长度的贡献约占3/4。3、阴茎勃起角度主要由阴茎海绵体内压力、游离段阴茎干尺寸、海绵体白膜的纤维分布以及阴茎固定段海绵体与水平面的夹角共同决定。其中阴茎海绵体内压力和游离段阴茎干尺寸分别是阴茎勃起角度形成的内在动力和主要阻力因素，而海绵体白膜的纤维分布以及阴茎固定段海绵体角度与水平面的夹角是其重要的结构基础。所建立的数学模型可以反映阴茎勃起角度、长度、海绵体内压力以及阴茎固定段与水平面的夹角之间的数学关系。结论1、根据既往手术资料统计分析所得的线性回归方程较以往的单纯的延长长度更能反映手术前后阴茎长度的变化规律，由其推导的预测公式可用于阴茎延长术后延长长度的初步的个体化预测，但其精确性有限。更为精确的预测需要从患者阴茎背根部的个体化结构着手。2、我们所建立的超声检查和分析方法可以应用于的阴茎延长手术病例的相关研究，其方法和结论可以为该手术延长效果的个体化预测提供必要的理论和方法支持。3、本研究结论，在理论上可以通过海绵体内压力将阴茎勃起角度等形态学指标与血流动力学、结构动力学指标统一起来，从而完善了阴茎勃起机制相关理论；在临床上可以指导阴茎勃起角度异常病例的治疗方法的选择，也可以实现通过形态学数据估算海绵体内压力，从而利于临床上更简便、科学地对阴茎勃起状态进行评估，此外，还可以用于指导阴茎延长手术个体化手术方案的设计，具有一定的实用价值。更多还原

【Abstract】 BackgroundPenis is an important urinary and reproductive organ, and the size of which plays aspecial role in male’s physiology and psychology. People usually believe that “bigger isbetter”, and many males with a short penis, even normal size, hope to enlarge their penisesthough any surgical or non-surgical approaches. Suspensory ligament dissecting penilelengthening was reported firstly in rectification of congenital epispadias and bladderexstrophy. As further studies in penile suspensory ligament and surrounding structures, theindication of this operation gradually expanded to short penis caused by various congenitalor acquired reasons, such as penile dysplasia, trauma and operations after penile carcinoma.The suspensory ligament dissecting is the more acceptable approach by doctors and patientsbecause of its simple method, lower influence to erection and faster postoperative recovery.Actually, the efficacy and safety of this operation, specifically the operation effect and theinfluence to erection, were the most concerned issues in clinic.In recent years, there were some of disputes in operation effect. Firstly, the actualextended effect of the operation had not reached a consensus. The universal viewpointconsidered that this operation could obtain1~2cm in extended length, but the data indifferent reports existed obvious difference. Secondly, the postoperative satisfaction wasgenerally low in this operation. The reasons were that the patients usually had a higherexpectation preoperatively, but the extended lengths were usually very limited in most cases.Thirdly, the indications of this operation were unclear in clinic. Mondaini et al. reportedthat the men who sought penis lengthening in clinic mostly had a normal penile size. Thesemales usually had a higher expectation in extended length, and the operation effect usuallywould not satisfy them. For these reasons, many researches had conservative attitudes tothis operation. They thought this operation should not be operated extensively, especially tomales with a normal penile size. Actually, it might be helpless to improve the postoperative satisfaction by limiting the indications strictly. The key problem was to make patients’expectation correspond to the actual effect. Thus, an individual forecasting method wouldbe very useful to solve the disputes above-mentioned. An individual forecasting methodneeded a precise prehension of the influence of the regional structures caused by theoperation. However, current researches in the mechanism of the operation were too rough tosatisfy it, because there was lacking of effective study methods yet. Therefore, it wasimportant and urgent to find an effective and precise study method to investigate the precisemechanism for clinical extending and thorough researches of this operation.The penile lengthening procures the extended length through destroying the suspensionsystem of penis, so it is inevitable to influence the physiological function of this systemmore or less. The suspension system of penis contains the fundiform ligament, suspensoryligament and arcuate subpubic ligament, which fixes the corpus penis to the pubicsymphysis and maintains the superducting status in erection. The universal idea of thesuspension system affected by penile lengthening was that the operation brought littleinfluence to the “stability of penile erection”, but there was lacking of strict experimentalevidences to support it. Actually there was not related research in the “stability of penileerection” in traditional uronology, even a definite concept. In plastic surgery, the “stabilityof penile erection” in penile lengthening usually was used to indicate whether there was avisible swing or drooping of penis during erection. In this point of view, we suggested thatthe erection angle of penis might be a potential index representing this “stability of penileerection”. In order to distinguish with the hemodynamic stability of penile erection, we putforward a concept of “structural stability of penile erection” to represent the previous“stability of penile erection” in penile lengthening. However, there were limited literaturesreferring to erection angle in uronology and andriatria as well. Thus, we firstly had toinvestigate the formation mechanism of erection angle and the relationship of the erectionangle and structural stability of penile erection, in order to study the influence of thesuspension system affected by penile lengthening.MethodThis research consist three parts as follow:1. A total of322patients were diagnosed congenital penile shortness and receivedpartial suspensory ligament release in our department since1988. Firstly all the patients were divide into two groups, named the Modeling Group (200patients) and the CheckingGroup (122patients). Then a two-dimensional model of the suspensory-ligament-releasepenis lengthening was established. For the Modeling Group, a statistical analysis of thepenile length in flaccid and erectile state before and after penis lengthening was carried out,and a forecasting predictive function of increased penile length was derived. At last, theforecasting error of the Modeling Group and the Checking Group were compared.2. The ultrasonograph and MRI were firstly examined in3patients preoperatively andpostoperatively. Then, the corresponding images of ultrasonograph and MRI werecontrasted to investigate the displaying status of dorsal root of penis in ultrasonograph.Finally, the preoperative and postoperative ultrasonograph images were contrasted toinvestigate the precise changes of regional structures caused by the operation.3. The formation mechanism of erection angle was discussed through literature review.Based on the mechanism, a mathematic model of erection angle was established. Then, theintracavernous pressure, erectile angle and length on ex vivo fresh corpse were measured,and the parameter of the model was computed from those measured data.Results1. There is a significant linear correlation between the increased length in flaccid anderectile state (R=0.921, P <0.01), a similar relationship between the extension rate oferection before and after the operation (R=0.803, P <0.01), as well as preoperative flaccidlength and extension rate of erection (R=-0.803, P <0.01). According to the significantlinear correlations shown above, two regression forecasting models are established. Apredictive function of increased flaccid length is derived from the two regressionforecasting models. The effectively forecasting rate is84.5%(the Modeling Group) and87.7%(the Checking Group) when the absolute value of forecasting error is less than1.5cm.2. The ultrasonograph could display the major structures of dorsal root of penis. Afterthe operation, the released corpus cavernosum usually would have a downward (leg side)displacement and an axial prolongation. But a part of released corpus cavernosum washidden in corpore again because of the thickening of presymphysial soft tissue. Thecontributions of the decrease of fixed segment of penis and the axial prolongation ofreleased corpus cavernosum were about1/4and3/4of flaccid absolute extended length respectively.3. The formation mechanism of erection angle mainly depended on the intracavernouspressure, the size of free segment of penis, the distribution of elastic fiber in tunicaalbuginea and the angle between fixed segment of cavernosum and horizontal plane. Theconstructed mathematic model of erection angle could reflect the functional relation of thedeterminative factors shown above. And the parameter of the model could be calculated bythe measured data.Conclusions1. The discovered significant correlation and the established forecasting functionprovide us a model of roughly and individually forecasting the feasible extended penilelength before penis lengthening. But the accuracy of the forecasting model is limited.2. This study is useful to prehension the mechanism and significance of the operation,and might provide some supports in theory and method for forecasting the extended lengthprecisely and individually. In addition, it might degrade the blindness and risk of operativeprocedure.3. The formation mechanism and mathematic model of erection angle we worked couldenrich the theory of penile erection mechanism. Besides, it could be referred for choosing aright treatment for penile lengthening, abnormal erection angle and an evaluation oferection state conveniently and scientifically in clinical practice.更多还原