Microdissection TESE: sperm retrieval in non-obstructive azoopsermia. VIDEO
Authors: P. Schlegel
Journal: Human Reproduction Update (1998)

Many men with non-obstructive azoospermia will have fully formed spermatozoa within their testes that can be extracted using biopsy or aspirations. Recent studies suggest that sperm extraction by open biopsy will find spermatozoa for more men with non-obstructive azoospermia than that obtained with percutaneous aspiration (Friedler et al., 1997). However, open biopsies carry potential risks of injury to the testis (Schlegel and Su, 1997), and often remove unnecessarily large volumes of testicular parenchyma. In this video, we demonstrate a technique of testicular microdissection that minimizes the amount of tissue removed during testicular sperm extraction (TESE), while optimizing the chance of finding spermatozoa for use with assisted reproduction. In the video, intraoperative views of sperm extraction are provided during two operative cases. The view is through an operating microscope. The testis in the first case is measured directly at 1.5 cm in maximum length. The subtunical vessels are identified under the operating microscope and avoided. A stay suture of 6‐0 polypropylene is placed into the tunica albuginea. A linear incision across the surface of the testis is transversely made using an ophthalmic ‘ultrasharp’ knife, with care taken to avoid subtunical vessels. The testis is initially opened and dissection bluntly performed between the septae of the testis to expose multiple areas of the testicle. Irrigation with Ringer’s lactate solution is copiously used to prevent blood from obscuring the view of the testicular parenchyma. In the first case, most of the testis is composed of immature stromal elements, and random biopsies would likely yield no spermatozoa. However, in one corner of the incision, seminiferous tubules are seen. These tubules are dissected under the microscope to isolate the larger tubules that are then excised. A second procedure on another patient reveals the ability of the microdissection technique to identify blood vessels within the testicular parenchyma. This dissection helps to prevent injury to the vascular integrity of the testis. Bipolar diathermy is used to limit bleeding, but its application should be minimized to avoid creating excessive local heat that may destroy spermatozoa. Despite a large volume of tubules with sclerotic features suggestive of a histological Sertoli cell-only pattern, an individual clump of tubules is identified with normal spermatogenesis. These tubules alone are excised, providing the embryologist with less tissue to dissect to find spermatozoa. In addition, the patient is left with an optimally preserved testis. Despite the larger incision in the tunica albuginea, our microdissection approach allows excellent preservation of the testicular blood supply and testicular tissue, with optimized sperm retrieval. This technique has now been attempted during over 30 TESE attempts for non-obstructive azoospermia at our institution. For one-third of the cases with spermatozoa found, the spermatozoa were only present in microdissected samples, not in adjacent large random biopsies. Microdissection during TESE limits the need to remove testicular tissue and maximizes the chance of finding spermatozoa for assisted reproduction.