Physiological Consequences of Testicular Sperm Extraction

Peter N.Schlegel1 and Li-Ming Su that testicular spermatozoa have the ability to fertilize oocytes and produce viable embryos for men with NOA (Devroey James Buchanan Brady Foundation, The Department of Urology, et al., 1995; Kahraman et al., 1996; Schlegel et al., 1997). The New York Hospital–Cornell Medical Center, and The Jow et al. (1993) suggested that spermatozoa could be found Population Council, Center for Biomedical Research, New York, NY 10021, USA in a single testis biopsy sample from 34% of men with NOA. Multiple biopsies can be used to retrieve spermatozoa in 48– 1To whom correspondence should be addressed at: Room F-907A, Department of Urology, The New York Hospital–Cornell Medical 86% of men with NOA, suggesting the presence of patchy Center, 525 East 68th Street, New York, NY 10021, USA regions of minimal sperm production (Devroey et al., 1995; Kahraman et al., 1996; Tournaye, 1996; Schlegel et al., Testicular sperm extraction (TESE) may provide spermato1997). The technique of acquiring testicular spermatozoa zoa for attempts at fertility with assisted reproduction; using testicular sperm extraction (TESE) was described by however, the physiological effects of TESE on testicular Schoysman et al. (1993) as well as Craft et al. (1993) for function are not well understood. In order to evaluate the obstructive azoospermia and subsequently by Silber et al. effects of TESE on the testis, 64 patients were evaluated (1995) and Devroey et al. (1995). Since then, TESE has after TESE for non-obstructive azoospermia with physical been increasingly performed as a therapeutic procedure in examinations, serial scrotal sonography, histological anaconjunction with ICSI for both obstructive and non-obstructive lyses and evaluation of the success of repeated sperm azoospermia. Studies to date have focused on the remarkable retrieval attempts. At 3 months after TESE, 82% of potential to retrieve viable spermatozoa from the testis using evaluated patients had ultrasonographic abnormalities in TESE despite the histological findings of maturation arrest, the testis suggesting resolving inflammation or haematoma Sertoli-cell-only, or hypospermatogenesis on testis biopsy that at the biopsy site. By 6 months, these acute inflammatory changes typically resolved leaving linear scars or calcificaare characteristic of NOA. However, little is known about the tions. Two patients had documented impaired testicular physiological consequences of TESE on testicular function. blood flow, with complete devascularization of the testis Spermatogenesis is an intricate process of 74 days duration for one patient after TESE with multiple biopsies. Repeat that is highly sensitive to toxic effects and even minor TESE procedures were far more likely to retrieve spermatoalterations in temperature. Therefore, inflammatory changes in zoa if the second TESE attempt was performed >6 months the testis following testicular surgery could adversely affect after the initial TESE procedure (80%), relative to those the spermatogenic process. performed within 6 months (25%). Transient adverse Vascular injuries can also occur from testicular surgery. The physiological effects are common in the testis for up to 6 testicular blood supply is derived primarily from branches of months after TESE. In addition, permanent devascularizthe internal spermatic artery, with collateral branches off the ation of the testis can occur following TESE procedures cremasteric and vasal arteries (Schlegel and Chang, 1991). with multiple biopsies. The risk of this complication may Regardless of its source, the testicular blood supply penetrates be minimized by using an open biopsy technique with the tunica albuginea covering the testicular parenchyma and optical magnification to directly identify testicular vessels. travels extensively under the tunica albuginea but over the