Yet another method of treatment, but less effective than puncture or aspiration, consists in injecting into the sac, after the removal of its contained fluid, certain agents toxic to hydatids. A solution of the extract of fern, alcohol, solution or tincture of iodine, and bile, are the chief remedies thus employed. It has long been known that bile is destructive of these parasites, and cases have occurred of spontaneous cure in which the opening of the growing cysts into a bile-duct has secured the entrance of bile and consequent arrest of growth and atrophy of the hydatids. Several successful cases have been reported in which the injection of aspidium (male fern) was the effective agent, but the threatening symptoms produced by it, and the comparative freedom of other methods of treatment from such disturbances, do not recommend the injections of fern. In the case reported by Pavy224 the extract of fern was mixed with a solution of potassa.
224 Lancet (London), July, 1865.
Injections of iodine in solution or in the form of tincture have been more frequently practised than of any other material. Davaine,225 who finds it less successful than simple puncture and aspiration, recommends, as affording the best results, a dilute aqueous solution of iodine. Alcohol, a solution of permanganate of potassium, and various antiseptic agents have been used to some extent, but none of them possess any advantages over more simple measures.
225 Op. cit., p. 650.
The latest proposal for the treatment of hydatid cysts, and probably the most effective consistent with entire safety, is electrolysis. Originally suggested by Althaus226 to those who first employed the measure on any considerable scale, it had been mentioned thirty years before by Budd, and appears to have been first practised in Iceland on a single case. The first elaborate attempt to establish electrolysis on a sound basis as a regular procedure was made by C. Hilton Fagge and Mr. Arthur E. Durham.227 They operated on eight cases, and all were successful. The method consists in the introduction of two needles connected with the negative pole, and the application of the positive—a moistened sponge—on the exterior in the neighborhood of the hepatic region. The strength of current employed by Fagge and Durham was that furnished by a battery of ten cells, and which by previous trial was found to decompose a saline solution. The two electrolytic needles, connected with wires attached to the negative pole, were introduced into the most prominent part of the tumor about two inches apart. The current was allowed to pass about ten minutes usually, sometimes a little longer, the sponge on the exterior—the positive pole—being shifted occasionally. The immediate effects are not considerable. The tumor may be rendered somewhat more tense and appear to be enlarged, but more frequently it becomes softer and is lessened in size, the increase of size being due to the disengagement of hydrogen gas, and the diminution caused by the escape of more or less fluid. The immediate effects of the operation varied. In one case no symptom followed, and in this the result was regarded as doubtful, although a cure was considered probable. In the others more or less constitutional disturbance followed, the symptoms being pain and fever, the temperature ranging between 100° and 103° F. The duration of the fever was from two to nineteen days, the latter in one case only. As has been observed in some of the cases treated by puncture or by aspiration, a rash appeared on the skin—in some instances scarlatinous, in others of urticaria. It is a curious circumstance that an eruption of urticaria is reported to have appeared in one subject in whom a rupture of the sac into the peritoneal cavity is supposed to have occurred.
226 On the Electrolytic Treatment of Tumors, etc., London, 1867.
227 Medico-Chirurgical Transactions, 1871, p. 1 et seq.
Although so little change in the tumor occurs immediately after the operation, yet it undergoes slow absorption, and ultimately disappears. The time occupied in the disappearance of the tumor varies from a few weeks to many months, the difference being due probably to the situation of the growth, those occupying the substance of the liver requiring a longer time to fill up.
Fagge and Durham report a case in which simple acupuncture was followed by a result apparently as good as obtained by electrolysis, and other similar experiences have been published. If the simple introduction of a needle suffices to arrest the growth of a hydatid cyst and induce its atrophy, of course the more complex procedures will be abandoned.
The tendency of the treatment of hydatid cysts has constantly been toward simplicity, and the success occurs in a direct ratio thereto. In forming an estimate of the relative value of the methods of treatment, the average of mortality of each plan becomes the most important factor. Simple tapping and paracentesis, the most frequently adopted mode of treatment, is not without immediate and remote danger. Of 46 cases carefully tabulated by Murchison,228 there were 3 deaths properly attributable to the operation; but the after results—suppuration of the cyst and its consequences, peritonitis, etc.—cannot be measured so accurately. About two-thirds of the cases thus treated result in cure, and in a majority of these a single operation suffices. The injection of the various substances which have been employed for that purpose does not seem to increase the proportion of cures, and their use distinctly enhances the dangers of the treatment. At present, the decision as to the method of treatment to be employed in any case should be made between simple tapping, electrolysis, and acupuncture. Of these, the last mentioned, it can hardly be doubted, is the method which is most desirable, for although it has not been employed so largely as the others, thus far the results have been better: the percentage of recoveries without accident has been higher relatively than by other methods of treatment. As acupuncture presents no special difficulties or dangers, and is but little painful, it may be tried first, reserving more formidable measures for the failures by this simple expedient.