Erich E. Brueschke

Development of a Reversible Vas Deferens Occlusive Device. III. Morphology of the Human and Dog Vas Deferens: A study with the Scanning Electron Microscope *

The luminal epithelium of the human and dog vas deferens was studies with a scanning electron microscope. Care had to be taken in preparing the vasa since the columnar cell layer was readily removed from the underlying basal cells and the basement membrane. The luminal surfaces of both dog and human vasa were covered with microvilli. Occassionally cytoplasmic extrusions were observed protruding from the center of a microvillus patch. Foreign cells present in 1 specimen formed spherical impressions on the villus surface. In accordance with previous reports with the transmission electron microscope 2 types of columnar cells were found. One was long narrow and straight; the other possesed a rounded upper portion and a narrow base (stalk). Both columnar cell types appeared to rest on the basement membrane with a single point of attachment. The basal (cuboidal) cells were evenly space using tentacles to adhere to each other and the basement membrane. This membrane had a smooth surface and separted the epithelial cells from the collagen fibers which were present in large amounts in the connective tissue surrounding the vasal lumen. From the observations it appears that the human and dog vas deferens are highly similar in structure.(AUTHORS MODIFIED)

Development of a Reversible Vas Deferens Occlusive Device. II Effect of Bilateral and Unilateral Vasectomy on Semen Characteristics in the Dog

16 male beagles were used to study the effect of bilateral and unilateral vasectomy on the semen characteristics in the dog during research into the development of a reversible vas deferens occlusive device. Bilateral vasectomy of 8 dogs resulted in the immediate absence of spermatozoa from the ejaculate of 7 dogs indicating that the spermatozoa are stored in the epididymis and not partially in the ampullary region of the vas as in the human. No significant decrease in volume after bilateral vasectomy could be detected in the group as a whole but some individual dogs showed distinct changes. Unilateral vasectomy of 8 dogs resulted in an overall 50% decrease in total sperm count; again some individual variations were observed. These variations probably depended on the functional activity of the remaining testicle. After unilateral vasectomy volume decreases were noted with the amount of decrease proportional to the individual decrease in sperm count. There was no change in the percent of viable spermatozoa after unilateral vasectomy and there was no increase in abnormal sperm forms. Neither bilateral nor unilateral vasectomy appeared to affect the pH of the ejaculate. Details of the manual and artifical vagina collection methods and the vasectomy technique in the dog are described.(AUTHORS MODIFIED)

Development of a Reversible Vas Deferens Occlusive Device: V. Flexible Prosthetic Devices *

In contrast to the results with rigid-ended prosthetic devices implanted in the vas deferens of the dog, effective sperm transport was obtained for prolonged periods of time with flexible-ended (all soft) devices. Such transport could be halted by device occlusion with clips or shuttle stem valves. Opening the devices resulted once again in the passage of spermatozoa, indicating that these devices may be potentially useful as reversible male contraceptives. More research is necessary to determine the cause of an overall decrease in sperm output after device implantations and to evaluate any adverse side effects of such devices. Dacron velour-covered suture rings on the devices permitted effective tissue ingrowth and prevented leakage or recanalization.

Development of a Reversible Vas Deferens Occlusive Device. VI. Long-Term Evaluation of Flexible Prosthetic Devices *

Fifty-three dogs received implants of several types of flexible devices containing valving mechanisms. These devices were constructed entirely of silicone rubber with the exception of the valve stem, which was made of stainless steel. Generally, the devices were (1) implanted in the open mode and left this way for 27 to 44 months, (2) implanted in the closed mode and kept this way for 11 to 12 months before the valves were reopened, (3) implanted in either the closed or open mode and cycled to the opposite mode every 3 months (four or five cycles), or (4) implanted in either the closed or open mode and cycled to the opposite mode every 6 months (two or three cycles). Different implant methods were also evaluated. Semen analyses were regularly performed on all of the dogs, and a number of the animals were bred during the experiments. It can be concluded that (1) the devices can be opened and closed successfully over long periods, respectively allowing and preventing sperm transport; (2) the breeding ability of the animals is not impaired while the devices are in the open mode, independent of the type of device; (3) the devices do not result in an enhanced incidence of congenital abnormalities in the offspring; and (4) the success rate of device performance does not depend on the method of implanatation used. Thus, the results clearly indicate that the basic mechanism of a soft, reversible valve is a feasible approach to conception control.

Development of a steerable hysteroscope: Studies in the baboon

A steerable fiberoptic hysteroscope was developed with an integrated fluid circulatory system and a channel that can be used either for operative procedures or for the passage of a uterotubal occlusive device delivery assembly. The hysteroscope was demonstrated to be a safe and practical instrument for intrauterine observations, using the baboon as the animal model. Postpartum baboons were used for a majority of the experiments since the cervix of most cycling animals could not be sufficiently dilated to permit hysteroscope insertion. Estrogen-progesterone treatment resulted in softening of the cervix enough to allow hysteroscopic examination in 66 per cent of the animals so treated. Hysteroscopy was performed on 18 baboons. In almost all cases the uterotubal junctions were visualized and appeared as small slits or depressions. Measurements of the mean uterine length, fundal width, normal cervical diameter, and the diameter to which the cervix can maximally be dilated are reported for cycling, hormone-treated, and postpartum baboons.

Development of a Reversible Vas Deferens Occlusion Device. VII. Physical and Microscopic Observations after Long-Term Implantation of Flexible Prosthetic Devices*†

Flexible prosthetic devices developed previously to reversibly block sperm transport through the vas degerens were implanted in the vasa deferentia of dogs or kept in a semen bath for a 6-month period. Dimensional measurements, flow characteristics, leakage tests, and detent action force tests to displace the valve stem were performed with the valves. No changes occurred in any of these parameters with the exception of a decrease in the force required to change the position of the valve stem. This explains the occasional passage of spermatozoa through certain closed devices after they have been implanted for long periods of time. Histologic studies indicated that the same types of genital tract changes are associated with an implanted device as with vasectomy, and that they occur with approximately equal frequencies. Scanning electron microscope studies showed (1) excellent tissue ingrowth into the Dacron velour material of the implanted device; (2) the build-up of material, consisting in part of spermatozoa, in the device lumen and on the value stem; and (3) the absence of surface degradation of either the Silastic material or the valve stem of the device. It is concluded that no irreversible tissue damage is caused by the long-term implantation of flexible prosthetic devices into the vas deferens.

The Human Uterotubal Junction: A Scanning Electron Microscope Study During Different Phases of the Menstrual Cycle**Supported by the Contraceptive Development Branch, Center for Population Research, National Institute of Child Health and Human Development, National Institutes of Health, under Contract NIH-NICHD-2233.

Uterotubal junctions from surgically extirpated human uteri were examined. The specimens were obtained during different phases of the menstrual cycle. The interstitial portions of the tubes together with the cornual areas were dissected, excised, and their luminal surfaces exposed. The specimens were then processed for scanning electron microscopy. The surface epithelium of both the cornual endometrium and interstitial endosalpins. Ciliated cells were more numerous in the endosalpinx. Cyclic changes in ciliated cells were minimal, while cyclic secretory activity was demonstrated, especially in the endometrium. The transitional area between the endometrium and the endosalpinx was characterized by a marked increase in the number of ciliated cells, and a tendency of the secretory cells to assume a flattened, polygonal shape. These morphologic features suggest a possible role in the transport and/or maintenance of spermatozoa and/or ova.