WHO定義,經過一年以上的無避孕性生活,而沒有成功受孕,即稱為不孕症,不孕症終其一生影響了約六分之一的夫妻,在這些夫妻當中,男性配偶佔約一半有精液品質的問題。在男性不孕中,精索靜脈曲張(varicocele)非常常見。
甚麼是精索靜脈曲張
精索靜脈曲張的成因與下肢精脈瘤發生類似,與先天問題或缺乏靜脈瓣膜有關,當靜脈瓣膜缺乏血液流入精索靜脈,靜脈叢中的靜脈血管擴張而導致遠端滯留,因為左側精索靜脈流向左腎靜脈的角度垂直,加上隨著腸系膜上動脈穿過左腎靜脈,靜水壓較右側甚高,故此病常發生於左側。精索靜脈曲張在臨床表現上可以分成四級(參考:男性不孕的評估(上)-關於病史的詢問與理學檢查與男性不孕的治療(上)—手術治療),患者常因陰囊墜脹感或鈍痛就醫,會因長時間走路、久站、性行為而加重。
精索靜脈曲張的流行病學
一般男性族群中,精索靜脈曲張在2-10歲男孩中,發生率<1%,至15-19歲青少年中發生率增加,但在不孕的男性患者當中,比例增加至40-50%以上。
精索靜脈曲張如何導致不孕
目前精索靜脈導致不孕的原因仍然未知,是多因素的,研究圍繞在氧化應激(oxidative stress),研究發現與健康男性相比,精索靜脈曲張不孕男性,活性氧(ROS)類似物較多,造成生精細胞凋亡。另外因靜脈擴張瘀滯,使陰囊與睪丸的溫度上升損害正常的精子產生。
精索靜脈曲張的治療
精索靜脈曲張的西醫治療目前以手術治療為主,可分為後腹膜腔(Retroperitoneal ),腹腔鏡(Laparoscopic ),腹股溝(Inguinal ),腹股溝下(Subinguinal),或是顯微(Microsurgical )等手術,手術併發症常以陰囊水腫、睪丸萎縮、或是再復發為主,因病人常是青春期無症狀健檢被發現,或是無症狀因不孕被意外發現的,精索靜脈曲張有可能漸進性的影響精子的生成,因此治療的選擇仍需要醫生綜合性的評估!
Reference:
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