Two groups have taken innovative steps to match technology with important clinical problems: the microscope with NOA and the Whitaker test with EDO.
Preliminary work by Turek et al at the University of California, San Francisco, has shown that a modified manometry test may be useful in detecting ejaculatory duct obstruction (EDO), which is seen in about 5% of male infertility cases (see, "Novel test diagnoses ejaculatory duct obstruction," page 1).
Currently, the diagnosis of EDO is most commonly made on the basis of ultrasound findings of dilated seminal vesicles or a cyst inside the prostate. Such findings are merely presumptive evidence of EDO, however, as many of these men do not develop sperm in the ejaculate when their ejaculatory ducts are transected. Other techniques-aspirating the seminal vesicles to look for sperm and placing dye in the ejaculatory ductal system to determine its patency-also can be used to show evidence of anatomic EDO. But none of these methods are accurate in demonstrating functional EDO.
In a second study, Schlegel et al from Cornell University, New York, have provided strong evidence that microdissection testicular sperm extraction (TESE) is an optimal means of extracting sperm from men with nonobstructive azoospermia (NOA) (J Urol 2007; 177:1447-9).
Nearly a decade ago, Schlegel first described microdissection TESE, in which a bivalved testis is systematically searched under the microscope for areas where seminiferous tubules may be dilated (Hum Reprod 1999; 14:131-5). His early groundbreaking work showed that not only was the technique effective in retrieving sperm in men with NOA, but also that the preferential dissection of tissue from dilated tubules allowed more sperm to be retrieved from less tissue.
One question remained: In men who have had multiple negative testis biopsies, is it still possible to retrieve sperm? Schlegel et al's recent research has demonstrated that there is, in fact, no limit to the number of negative biopsies that precludes the successful use of microdissection TESE. Even in those men who underwent four biopsies that were negative, the researchers were able to retrieve sperm in a reasonable number of men using the microdissection approach.
Both the Cornell and UCSF groups have taken innovative steps to match technology with important clinical problems: the microscope with NOA and the Whitaker test with EDO, respectively. These advances clearly demonstrate the creative approach to surgical problems for which urologists are well known, and solve problems to benefit practicing urologists and patients alike.
Craig S. Niederberger, MD