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Fine needle aspiration (FNA) cytology has been used to examine pathological human tissue from various organs for over 100 years.〔,Posner C. Die diagnostische Hodenpunktion. Berl Klin Wochenschr 1905;42b:1119-1121〕 As an alternative to open testicular biopsy for the last 40 years, it has helped to characterize states of human male infertility due to defective spermatogenesis.〔Hendricks FB, Lambird PA, Murph GP. Percutaneous needle biopsy of the testis. Fertil Steril.1969; 20:478-81〕 Although recognized as a reliable, and informative technique,〔Gottschalk-Sabag S, Glick T, Weiss DB. Fine needle aspiration of the testis and correlation with testicular open biopsy. Acta Cytol 1993;37:67-72.〕〔Mallidis C, Gordon Baker HW. Fine needle tissue aspiration biopsy of the testis. Fertil Steril 1994;61:367-375.〕 testis FNA has not been widely used in U.S. to evaluate male infertility. Recently however, testicular FNA has gained popularity as both a diagnostic and therapeutic tool for the management of clinical male infertility for several reasons: #The testis is an ideal organ for evaluation by FNA because of its uniform cellularity and easy accessibility. #The trend toward minimally invasive procedures and cost-containment views FNA favorably compared to surgical testis biopsy. #The realization that the specific histologic abnormality observed on testis biopsy has no definite correlation to either the etiology of infertility or to the ability to find sperm for assisted reproduction. #Assisted reproduction has undergone dramatic advances such that testis sperm are routinely used for biological pregnancies, thus fueling the development of novel FNA techniques to both locate and procure sperm. For these reasons, there has been a resurgence of FNA as an important, minimally invasive tool for the evaluation and management of male infertility. ==Changes to Infertility Medicine== Advances in assisted reproductive technology (ART) have revolutionized the ability to help men with even the severest forms of male infertility to become fathers. This field began in earnest in 1978 when the first successful in vitro fertilization (IVF) cycle was performed. This technique involves controlled ovarian stimulation followed by egg retrieval, in vitro fertilization, and embryo transfer to the uterus. In the United States, the number of babies born to infertile couples with IVF has risen logarithmically from 260 babies in 1985 to almost 50,000 in 2003. Another significant advance in ART was the development of intracytoplasmic sperm injection (ICSI) in 1992.〔Palermo G, Joris H, Devroey P et al. Pregnancies after intracytoplasmic injection of single spermatozoon into an oocyte. Lancet 1992; 340: 17.〕 Performed in conjunction with IVF, ICSI involves the injection of a single, viable sperm directly into the egg cytoplasm in vitro to facilitate fertilization in cases of low sperm numbers. ICSI has decreased the numerical sperm requirement for egg fertilization with IVF from hundreds of thousands of sperm for each egg to a single sperm. In addition, ICSI allows sperm with limited intrinsic fertilizing capacity, including “immature” sperm obtained from the reproductive tract of men with no sperm in the ejaculate to reliably fertilize eggs. Indeed, ICSI has become so popular that U.S. clinics have routinely used it in more than 56% of their IVF cases. The success of ICSI has also encouraged reproductive clinicians to look beyond the ejaculate and into the male reproductive tract to find sperm. Currently, sources of sperm routinely used for ICSI include sperm from the vas deferens, epididymis, and testicle. Interestingly, as ART has evolved, so too have novel FNA techniques to help diagnose and treat severe male infertility. An example of this is use of testicular FNA “mapping” to systemically assess and localize sperm for ART in men with azoospermia (no sperm count) and with testis failure characterized by “patchy” or “focal” spermatogenesis.〔Turek PJ, Ljung B-M, Cha I, Conaghan J. Diagnostic findings from testis fine needle aspiration mapping in obstructed and non-obstructed azoospermic men. J Urol 2000;163:1709-1716〕 Indeed, this combination of techniques has allowed men with even the severest forms of infertility, including men who are azoospermic after chemotherapy for cancer, to become fathers.〔Damani MN, Master V, Meng MV, Turek PJ, Oates RM. Post-chemotherapy ejaculatory azoospermia: Fatherhood with sperm from testis tissue using intracytoplasmic sperm injection. J Clin Oncology 2002; 20: 930-936.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「FNA Mapping」の詳細全文を読む スポンサード リンク
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