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professors of language in conference but by the whimsof the man in the street, not because their derivation isimpeccable but because they do their job better thantheir predecessors. So it must be with debridenaent. Ifit means relief of tension, as undoubtedly it does orrather did, do we need it at all ’? Is one long Frenchword better than three short English ones ? ‘? Does it sayanything new or describe anything old more clearly,more concisely or more beantifully z? If on the otherhand it means all the steps of surgical wound sterilisationelaborated in the last war and practised, possibly withmodifications, in this, as it undoubtedly did to the

surgeons who developed that technique and to the

majority of those who use it today, it becomes a usefuland indeed an indispensable word. It saves time in

writing and unnecessary repetition of technical details tothose who are already familiar with them.

These points will be settled eventually by the con-sensus of surgical opinion, and settlement will comeeasier and sooner if we admit that the word is no longerFrench, but has become part of the vocabulary ofBritish surgeons. Let us remove the accent and dropthe italics. As debridement it is our word, one that wecan pronounce as we like and use to convey the meaningfor which it is most needed without reference to thedictionary.

ORIGINS OF HEADACHES

Penfield z originally followed up the work of Foersterand others who have studied the mechanism of head-aches by stimulating the exposed brain, dura, andintracranial blood-vessels and noting the resultingsensations. Now, with MeN aughton2 he has investigatedthe anatomical background of his previous clinical andexperimental observations. He found that the brain itselfand the intracerebral blood-vessels were insensitive, butthat the walls of the dural sinuses, the large intracranialarteries, and some areas of the dura were extremelysensitive. Pain produced by dural distortion-that, forexample, due to pressure upon the falx and tentorium-was referred to a distance from the point of stimulation,while stimulation of the larger arteries caused local pain.Some areas of the meninges were more sensitive thanothers-for instance, stimulation of the posterior thirdof the falx caused severe pain, and the walls of thesinuses and points of entry of veins had a much greatersensitivity than the rest of the dura. Whether pressure,traction, heat, or electricity were used as stimulants theresulting pain had always the same quality ; it was, infact, a headache, and was sometimes accompanied bynausea, vomiting and restlessness. The reference of theheadache following local stimulation was usuallyipsilateral, but was often far removed from the point ofstimulation. For instance pressure upon the tentoriumor upon the posterior part of the falx caused a frontalheadache. The reference of this pain is explained by theanatomy of the nerve-supply of the cerebral dura mater,which is all, except for that in the posterior fossa, suppliedby the trigeminal nerve. Fibres from the second andthird division, and sometimes from the first, pass up withthe middle meningeal artery to supply the lateral cranialwalls, while the superior longitudinal sinus and falx areinnervated mainly by the ophthalmic division via thetentorial and anterior ethmoid nerves. The tentorialnerve also supplies the superior wall of the transversesinus, but its inferior surface and the dura of the posteriorfossa receive a nerve-supply from the vagus, and alsoperhaps from the ninth and tenth cranial nerves.

Although much of this area is very sensitive, nerve-end-ings are difficult to find, and their number varies fromcase to case. This may explain the wide individualvariation found in the sensitivity of these structures.

1. Penfleld, W. Ass. Res. nerv. ment. Dis. Proc. 1935, 15, 399.2. Penfield and McNaughton, F. Arch. Neurol. Psychiat. July,

1940, p. 43.

Penfield and McNaughton also describe a series ofcases where pain related to dural scars or deformity wasrelieved by denervation of the dural sinuses or by sectionof the appropriate division of the trigeminal nerve.

They conclude that although headaches have beenattributed variously to irritation of the dura, the

meningeal and cerebral arteries, and the ventricularwalls, the dura with its sinuses and tributary veins is thecommonest site of origin. They suggest that treatmentof intractable headache should not be abandoned untilthe pain mechanism has been studied in each case, andradical treatment has been undertaken to remove thelocal cause or, if necessary, to section the appropriatesensory nerves.

EXTERNAL HYSTEROGRAPHY

FoR many years obstetricians have been studying theaction of the uterus in labour both from a physiologicaland a pathological standpoint. Most of this work hasbeen done by careful clinical observation, but from timeto time the aid of scientific recording instruments, ofgreater or less accuracy, has been invoked. The first

hysterography studies are credited to Schatz 1 whointroduced into the uterus a small rubber bag of 80 c.cm.capacity connected to a revolving drum. Chassar Moir 2

used this method to assess the action of the ergot alka-loids on the uterus, and thereby established the value ofergometrine. This internal method, has, however, fourmajor disadvantages. First, it is a foreign body,, andlike any foreign body introduced into a hollow viscusmay set up unnatural contractions. Secondly, anyforeign body introduced into the upper reaches of thebirth-canal must, no matter how skilful the operatorand how ideal the aseptic ritual, carry with it at least asmall risk of infection. Thirdly, its introduction needs ananaesthetic which may itself influence uterine behaviour.Lastly, the use of internal apparatus requires an

elaborate technique of sterilisation, skilled assistance andattention. These manifest disadvantages have led tothe increasing use of an apparatus which is entirelyexternal, first devised by Schaffer in 1896. This methodis not ideal, since the record must take into accountvarious extraneous movements such as abdominalrespiratory excursions, aortic pulsation transmitted

through the uterus, vomiting, and in fact any movementof the patient ; but these superimposed tracings are

easily distinguished from the orderly sequence of theuterine contractions. A levered cork hammer is appliedto the maternal abdomen by means of a circular basewhich carries a pneumatic chamber ; the hammer isconnected to a rubber diaphragm in the pneumaticchamber, so that any excursion of the hammer is

interpreted via a recording tambour on a smoked drum.When the uterus contracts the anteroposterior diameterof the uterus and the abdomen increases ; this resultsin an upward deflection of the hammer and compressionof the air in the closed system, producing an upwardstroke on the drum. The whole apparatus is light andrides comfortably on the patient, who is thus permitteda fairly wide range of normal movements. MostynEmbry 3 has used this method to illustrate the effect ofvarious drugs, notably in cases of inertia. He finds thatgas administered by Minnitt’s apparatus does not

depress uterine contractions but enhances the intensityof individual contractions and increases the tone of theuterus ; even when administered in concentrations suffi.cient to produce anaesthesia it has little or no depressantaction. Ether used as an analgesic does not depressuterine action or retard labour, but when pressed to thepoint of anaesthesia the intensity of contraction islessened and the interval between contractions is

lengthened in direct proportion to the depth of the

1. Arch. Gynaek. 1872, 3, 58.2. Proc. R. Soc. Med. 1935, 28, 1654.3. J. Obstet. Gynœc. August, 1940, p.371.

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anaesthesia. Chloroform in small doses has the same effectas ether, but in larger doses acts as a more powerful andcomplete uterine depressant. Bromide and chloral, hefinds, have no effect on uterine action and any improve-ment in the action of the uterus after their use heattributes to their sedative effect on the higher centres.morphine acts in the same way except that 15 min.after the injection of gr. there is a slight but noticeablediminution in the intensity and frequency of the contrac-tions ; this is a transient phenomenon, lasting only30 min. at most, and not influencing the subsequentbehaviour of the uterus. The action of morphine withscopolamine is the same as that of morphine only. Healso investigated the oxytocic drugs and found thatquinine in gr. 10 doses is an unreliable stimulant. Infour patients on whom tracings were secured only oneshowed improved contractions. Pituitrin on the otherhand has a dramatic effect on the parturient uterus ;acting rapidly, it increases the power, frequency andduration of the contractions, but relaxation betweencontractions is incomplete ; in other words, a state ofpartial tetany is induced. The duration of this actionis about 30 min. even with small doses of 22 units.These hysterographic studies of the effects of pituitrinonce again confirm the grave dangers of its indiscriminateuse, the gravest being that of rupture of the uterus.Hysterography failed to show any demonstrable differencebetween pitocin, the separated oxytocic principle of

pituitrin, and pituitrin itself. Thymophysin is variablein action, and shows no particular advantages overpituitrin. (Estrin and acetylcholine have a variableeffect on the parturient uterus : in some cases a definiteincrease in contractions results quite soon after theiradministration, though this is never so dramatic as

after pituitrin. Embrey’s work confirms some and

repudiates others of our established theories of uterinebehaviour in labour, and the action of stimulant anddepressant drugs on the contracting uterus. Hystero-graphy should provide a reliable measure of old andnew therapies.

ANTISCORBUTICS

ANIMAL tissues are valuable sources of the fat-solublevitamins, but, with a few exceptions of secondarypractical importance, plant tissues are essential to manfor his supply of vitamin C. It is a fallacy, however,to consider that all plant tissues are equally importantantiscorbutics, and consideration of tables such as thosecompiled by Boas Fixsen and Roscoe reveals the

great variation in vitamin-C content of various fruitsand vegetables. The negligible amount of the vitaminin plums, pears and melons is in striking contrast to thehigh concentrations found in many other fruits and

vegetables. Citrus fruits have been accepted for somelong time as valuable antiscorbutics, but it was not until1936 that it was shown 2 that black-currants were threeor four times as potent as orange juice. Two-thirds ofan ounce of black-currants will provide the entireestimated daily dosage of 50 mg. of ascorbic acid. The

strawberry also now ranks with the citrus juices and isapproximately twice as rich as the tomato. Alongsidethis revision in the scale of accepted antiscorbutic valuesother false impressions have been corrected as the resultof recent investigations. Vitamin C was once regardedas a luxury vitamin restricted to those who could affordthe more expensive fruits. But price and antiscorbuticvalue do not necessarilv run side bv side and aboutld. a day spent on properly chosen foods will supplythe normal requirements of vitamin C.3 Anothercommon fallacy was that cooking and canning of fruits andvegetables destroyed most if not all the vitamin C present.1. Boas Fixsen, M. A. and Roscoe, M. H. Nutr. Abstr. Rev. 1937, 7,

823.2. Olliver, M. J. Soc. chem. Ind., Lond. 1936, 55, 153T.3. Olliver, Lancet, 1940, 2, 190.

Workers throughout the world-Kohman and Tresslerin America, Lunde and Mathiesen in Norway, andOlliver in England-have disproved this theory. Duringcooking a proportion of the vitamin is extracted fromthe tissues into the liquid but the actual destruction isrelatively small. Cooked, but not overcookecl, vege-tables such as brussels sprouts, cauliflower, cabbage,and spinach are among the most valuable antiscorbuticsbut it is a pity more use cannot be made of the despisedwater they have been cooked in. These new findings,which are of the utmost importance in time of warwhen the nation has to be fed on a restricted food-supply, are based on a mass of experimental work mainlyaccumulated during the past five or six years. As theJournal of the American -111edical Association 4 pointsout, these many observations have only been madepossible by the perfection of rapid chemical methods forestimating the vitamin, and the importance of the workof Tillmans, Harris, and others, by which a simple30-minute test can be substituted for a laborious threeto four weeks’ biological assay, cannot be overestimated.

POLIOMYELITIS OF MICE AND MEN

IT is too early to attempt to classify animal viruseswith the precision applied to bacteria, but it is possible toplace them in groups. These include the vaccinia-variola group, the Castaneda-positive group (made up ofthe viruses of psittacosis, trachoma, inclusion conjuncti-vitis and lymphogranuloma venereum), the influenza

group and so on. It may now become necessary to

speak of a poliomyelitis group. In 1934 Theiler whileworking in New York on the effects of the neurotropicyellow-fever virus in mice noted that a few uninoculatedmice from an apparently normal strain showed symptomsof a flaccid paralysis of the hind legs. From the brains ofthese mice a virus was isolated which is similar in size tothe poliomyelitis virus and like it gives rise to lesionswhich affect especially the cells in the anterior horn of thecord.6 A number of strains of this virus have beenisolated not only in America but in Germany, Japan andPalestine. Olitsky has now found that the same virusis carried in the intestines of a high percentage of normalmice in America, although few develop nervous svmp-toms. From the intestine the virus can be traced,according to Theiler and Gard,8 through the intestinalwall to the mesenteric glands. Monkeys are resistantand do not develop immune bodies after inoculation withthe mouse virus nor is there any serological relationshipbetween it and human poliomyelitis virus. Theseobservations might appear to have little bearing on humanpathology were it not for the discovery by Armstrong 9that the Lansing strain of human poliomyelitis virus istransmissible to the Eastern cotton-rat, Sigrnodo7zhispidus hispidus, and to the mouse by intracerebralinjection. The lesions in these species closely resemblethose found in the monkey (Lillie and Armstrong 10).After passage through the cotton-rat the Lansing viruswas shown by Peers 11 to have undergone no change in itspathogenicity for the rhesus monkey ; and Haas 12 foundthat 57 of 83 human sera possessed immune bodies to thisvirus, as judged by the reaction in mice, whether or notthe donors of the serum had a clinical history of polio-myelitis. The susceptibility of the Eastern cotton-rat tothe Lansing strain of human poliomyelitis was confirmedby Toomey and Takacs,l3 who also infected the closelyallied species, Sigmodoib hispidus littoralis. They were

4. 1940, 115, 863.5. Theiler, A. Science, 1934, 80, 122.6. Theiler, J. exp. Med. 1937, 65, 705.7. Olitsky, P. K. Ibid, 1940, 72, 113.8. Theiler and Gard, S. Ibid, pp. 49 and 79.9. Armstrong, C. Publ. Hlth Rep., Wash. 1939, 54, 1719 and 2302.10. Lillie, R. D. and Armstrong, Ibid, 1940, 55, 718.11. Peers, J. H. Ibid, p. 726.12. Haas, V. H. Ibid, p. 1061.13. Toomey, J. A. and Takacs, W. S. Proc. Soc. exp. Biol., N.Y.

1940, 43, 536.