CORONARY AND MYOCARDIAL DISEASE

878 ulcers does not depend, as your annotation states, on early and efficient treatment of varicose veins. When the leg-muscle pump has failed, from whatever cause, ulceration can be prevented if the œdema is controlled by elastic support. Once ulceration has appeared, early treatment is important. The longer an ulcer remains untreated the With the exception of ulcers more difficult is its cure. of many years’ duration, with much induration of the leg, which may require rest in bed, it is only necessary to abolish the œdema and the ulcer will heal. Rest in bed has serious social and economic disadvantages for most patients and carries a risk of venous thrombosis and stiffening of the ankle-joint. The value of surgery in the treatment is still uncertain. Until a defective leg-muscle pump can be repaired control of œdema by compression and massage by Bisgaard’s method offers the best chance of cure. Unless aftercare is adequate relapse is probable and permanent support by bandages or elastic stockings is required. As yet no surgical treatment can offer an alternative. It is high time that we appreciated that treatment of superficial varicose veins is no answer to the problem of leg ulcers. Moreover, it is sometimes the cause of ulceration, as in 33 patients (4·4%) in my series in whom deep thrombosis followed injection of varicose veins, and in 10 patients in whom ulceration was precipitated by saphenous ligation. In another 49 patients ulceration became worse or appeared after such ligation. S. T. ANNING. Leeds. POSSIBLE DANGER WITH CYCLOPROPANE

First has long been the slogan of anæsthetists, and it is with this in mind that I would like to point out a danger from cyclopropane with the machines in use at most hospitals. The rotometers of nitrous oxide, oxygen, and carbon

SIR,—Safety

dioxide are controlled by means of a screw-valve situated at their base, but in the case of cyclopropane this adjustment is affected by means of a circular key on top of the cylinder of cyclopropane on the aide of the machine. A movement of as little as 1 cm. is sufficient to turn on the cyclopropane from 0 to 750 c.cm. per min. ; and on many of the older cylinders this is achieved by the slightest touch. A nurse or orderly brushing past the machine in the theatre, or during the transit from anæsthetic room to theatre, can quite easily turn this delicate control either off or full on. Especially dangerous is the fact that the gas is sometimes accidentally turned on when the anæsthetist has not intended its use, and when, therefore, his eyes will not be as often as usual on that rotometer, which is in any case much smaller than the others.

Conversations with anæsthetist colleagues have shown that these accidents are by no means rare, and in my opinion the provision of a guard round the cyclopropane key is not a sufficient safeguard. For absolute safety the cyclopropane rotometer should be provided with a separate screw-valve of its own. FRANK R. RUSSELL. West Hartlepool. CORONARY AND MYOCARDIAL DISEASE

SiR,—In your issue of April 12, Dr. W. P. D. Logan contrasts the mortality-rates in different social classes from " coronary " and " myocardial " diseases, and in the second paragraph he defines coronary disease as including angina pectoris, and myocardial disease as myocardial and cardiovascular degeneration. Unless I am mistaken these terms all refer to the same patliological - entity-namely myocardial ischaemia due to coronary atherosclerosis. The terms used are, of course, those of our colleagues who certified the cause of death. In the case of terms such as coronary atheroma, coronary thrombosis, or angina pectoris, the meaning is clear. In the case of myocardial or cardiovascular degeneration the exact meaning is rather vague ; but I do not see that there is any other

than degeneration of the myocardium due to ischtemia. produced by coronary disease. It might be argued that the two sots of terms refer to coronaryv thrombosis and to coronary atherosclerosis without thrombosis, but this is a distinction that is difficult if not ijnpossible to make even at necropsy and certainly cannot be made clinically. May I suggest that it would aid clearer thinking if we used the term " ischæmic heart-disease" for all cases where we mean that the heart has failed for lack of a,

likely moaning

proper

blood-supply?

Department of Pathology, Postgraduate Medical School of London,

C. V. HARRISON. W.12. W.12. C. V. HARRISON

RADIOLOGICAL INVESTIGATION SIR,—I was very pleased to see that Dr. Peter Leggat (April 19) had given such prominence to my statement: " The fact that young adults die from undiagnosed pulmonary tuberculosis is not duo to failure to radiograph them, but to bad clinical examination." The statement is based on many years’ experience, with. sound and on such evidence as I have previously recorded of These men’s chest complaints were young soldiers. dismissed by their medical officers (not old medical practitioners)but when they went home on leave their non-medical parents recognised the disease and took them to the family doctor, who supported the diagnosis and had it confirmed by radiography or sputum exami. nation. No mass radiography of soldiers will prevent this : bad clinical work is usually associated with bad

clinicians,

radiology.

-

I have repeatedly examined patients sent by general practitioners who rightly detected the early signs and symptoms of tuberculosis, though I could find no signs of it at the first examination, or only minimal signs. (And when I say minimal I mean less radiographic "

mass workers " record under that term ;for they include not only old lesions but such as sometimes vanish within a few weeks without any treat. ment. I have seen that lobectomy has been performed on such within a few days of discovery. What a remarkable advance in the treatment of tuberculosis, and what clinicians !) I am not at all surprised to note that in a recent survey on minimal pulmonary tuberculosis Dr. Leggat discovered that " in over 60% of the cases there were no symptoms and in over 70% there were no signs." I shouldhave expected his figures to be nearer 100%. I have seen some patients, who because of their suspicious signs were referred by general practitioners to the chest expert, returned as normal ;; yet the parents were convinced that the disease was present, and I have established the diagnosis. When "he does not observe the early radiographic signs, the expert " sometimes becomes blind to the clinical evidence detected by the dctor, patient, and

evidence than

some

"

parents. If Dr. Leggat examines the figures of the Birmingham mass-radiography unit recorded by Dr. Halliday Suther.

land,! he will see that of the 157 cases of tuberculosis detected, 125 were found to have tubercle bacilli in the

sputum. As regards the other 32 cases, it remains to be proved that the disease was active and that, undiscovered by radiography, they would not have healed without any treatment or knowledge of the disease, as the greater majority of lesions do. Further, these examinations, though conducted with a mass-radiography unit, did not constitute mass radiography but an essential part of a clinical examination which general practitioner: sought for patients in whom they had found signs-9 very proper, reasonable, and economical method which was suggested by a radiologist 2 who has strongly criticised mass

radiography from its incention

1. Lancet, Jan. 19, 2. Brailsford, J. F.

1952, p. 152. Med. World, Lond. March 31, 1934.