Hereditary transmission is certainly a cause also of many diseases of the nervous system. Friedrich's ataxia is hereditary. It is an incurable progressive incoördination of the limbs, tongue, larynx, and eyes, which attacks commonly between the tenth and the twentieth year, and the patient dies from some intercurrent disease, usually an infection. Progressive muscular dystrophy is also hereditary and incurable. The legs and trunk atrophy, and death comes from an intercurrent disease. Related to this malady are hereditary progressive neurotic muscular atrophy, progressive spinal muscular atrophy in infants, and progressive spinal amyotrophy in adults. Amaurotic (amaurosis, blindness) family idiocy is hereditary, and the child dies at about two years of age. Huntington's chorea appears in every generation of an affected family. Its symptoms show between the ages of thirty and forty years, and it progresses from choreic and ataxic signs to dementia and death. The death is often by suicide. In eastern Long Island, southwestern Connecticut, and eastern Massachusetts 962 cases were all traced back to six persons, three of whom were probably brothers, who came to America in the seventeenth century. In the 3000 relatives of these choreics were 39 cases of epilepsy, 51 cases of cerebral inflammation, 41 cases of hydrocephaly, 73 feeble-minded children, and other evidences of neuroses. The heredity in this disease is apparently Mendelian. Besides the diseases enumerated here, there are several pathologic conditions of the eyes which are hereditary—presenile cataract, stationary night blindness, and retinitis pigmentosa. If the persons who have these diseases are sexually sterile, evidently the heredity so far as they are concerned will be cut across; hence the advocates of legal sterilization wish to have these patients sterilized to protect society.
The surgical operation by which the man is sterilized according to the State laws mentioned above is an interruption of the continuity of the vasa deferentia near the testicles. This interruption may be a severing of each vas, a cutting out of a part of each vas, or a ligation of the vasa. The term vasectomy is now used loosely to cover all these methods. The vas deferens, or seminal duct, passes from the testicle up along the groin on each side, in through the belly-wall by the inguinal canal, down along the pelvis and under the bladder, where it opens into the bottom of the urethra a short distance in front of the bladder exit. Each vas is about two feet in length, and it has a diameter of one-tenth of an inch throughout the greater part of its length, but its lumen is extremely narrow.
There are two essential parts in the semen, the spermatozoa and the carrying liquid. The spermatozoa, which fructify the ovum, are formed in the testicle; the liquid, which is the essential vehicle of the spermatozoa, and without which the spermatozoa are inert and sterile, is secreted, except a few drops from the testicles, at the distal end of the vasa deferentia under the base of the bladder, in the seminal vesicles, the prostate gland, and Cowper's and Littré's glands. The semen is made up of 90 per cent. water and 10 per cent. solids, and in these solids is the nitrogenous base called spermin, which is produced by the interstitial cells of the testicles and the prostate gland. Ovarin, secreted from the ovaries, corresponds in the woman to spermin in the man. The ductless glands, and some that have ducts, produce secretions which sustain the tone of the blood-vessels and neutralize the toxins from waste substances while these are in the body before excretion. An excess of spermin or ovarin causes congestion of the cerebrum and cerebellum and the nerve centres there, with consequent sexual erethism. When there is a pathologic sexual erethism from an excess of spermin or ovarin, vasectomy, castration, spaying, or the menopause cuts off this excess and the erethism disappears. Sometimes the waste product toxins excite the patient when the spermin or ovarin has been eliminated, just as the excess of spermin or ovarin excites, and the neurotic disturbance or sexual erethism continues until compensation by other glands neutralizes the irritating substance.
The testicles in man are by no means the sole organ of generation. There are at least seventeen distinct organs in the male generative system. The seminal vesicles with the prostate gland are as necessary in generation as the testicles, as their removal sterilizes the spermatozoa and prevents the formation of the liquid vehicle. Castration effects an atrophy of several parts of the generative tract, and an irremediable degeneration; vasectomy cuts off the spermatozoa but causes no atrophy or degeneration, and the condition is remediable. Dr. Edward Martin of Philadelphia found active living spermatozoa in a testicle that had been ligated off for twenty years.
Running along the vasa deferentia, within the sheath of the two spermatic cords, are the spermatic arteries, the pampiniform plexus of veins, and the deferential arteries. These vessels, with the vas deferens and the sheath enveloping the bundle, make up the spermatic cord. In vasectomy, under local anesthesia, a slit is made through the skin of the scrotum behind, the sheath of the spermatic cord is opened, and the vas is isolated and tied or cut. The skin wound is left to heal. This operation is repeated on the second vas. If the blood-vessels in the cord are ligated or cut with the vas, the testicle will atrophy; if the vas alone is operated upon, the testicle is not injured. The person upon whom vasectomy has been done is conscious of no change. The semen is discharged as before the operation, but in a slightly less quantity, and it is, of course, sterile from the lack of spermatozoa.
Dr. Carrington of Virginia reported, in 1910,[218] twelve cases of vasectomy on convicts. He said ten of this dozen had been confirmed masturbators, and all were cured by vasectomy. One masturbating epileptic was cured of both conditions. Two dangerous homicides were rendered harmless and peaceable. One of these two homicides was a negro under a long sentence for murder. He grew insane in prison, and while insane killed a second person. A confirmed masturbator and sodomist, and a dangerous savage, he became lucid and relapsed into insanity several times. A year after vasectomy he was "a sleek, fat, docile, intelligent fellow, a trusty about the yard."
Dr. Sharp of Indianapolis, after ten years' experience with the operation, during which time he did 456 vasectomies, says:[219] "There is no atrophy of the testicle, no cystic degeneration, no disturbed mental or nervous condition following." He says, further, that 176 men in the Indiana Reformatory asked him to perform the operation on them. Vasectomy tends to check masturbation, and the minds of the masturbators frequently improve after the operation.
If a man has been sterilized by vasectomy, restoration of function and removal of the sterility seems practically always possible. If a ligature has been used, releasing the ligature restores function. Dr. William T. Belfield of Chicago[220] restored function fully by removing the ligature eight weeks after it had been applied. In a letter to me, Dr. Belfield said: "My observation accords with the general experimental and clinical experience that the restoration of the lumen after vasectomy or ligation, or both, is more certain than the lasting occlusion of the vasa by these measures. The perseverance of natural forces in restoring the lumen of the vas—and the success achieved over such obstacles as silk ligatures—is surprising until one reflects upon the natural factors favoring such restoration. In one case I tied a waxed (to avoid cutting through) silk ligature tightly around the sheath of each vas; a specimen examined a month later was devoid of sperms; one six months later contained plenty of them. I cut down upon the ligatures, found them in place and neatly encysted, and removed them. Evidently the pressure from behind had squeezed a passage on at least one side. The gynecologists have learned that ligatures around the Fallopian tubes are apt to cut through, whereupon the tubal lumen is restored, though pressure must be less than in the vas. Even when a piece of the vas has been excised cases of spontaneous restoration have been observed in men and dogs."[221]