8. SPIRo HM: Clinical Gastroenterology, 2nd ed, New York, Macmillan, 1977, p 489 9. SCHAPIRO RL, NEWMAN A: Acute enterocolitis. Radiology 108: 263, 1973
Mammography and xerography To the editor: In his letter "Mammography and xerography" (Can Med Assoc J 116: 712, 1977) Dr. Paul H. Niloff wrote about misconceptions regarding mammography and xerography, which are the same investigation with different recording media. Dr. Niloff emphasized that the role of these radiographic studies is to diagnose nonpalpable neoplasms of the breast. I agree: that is indeed the most important and most spectacular role of mammography. I disagree, however, with his statement that 20% of malignant neoplasms are not detectable by mammography. The false-negative rate is closer to 10% or less in most reputable series. More important, however, mammography is very much indicated as a prebiopsy procedure in the investigation of breasts with one or more palpable masses. If the mass palpated is a neoplasm, one would have to rule out the presence of malignant disease as yet nonpalpable in the contralateral breast - an occurrence that is by no means rare. Even if the mass is benign, a nonpalpable malignant tumour may lurk behind it and may remain undetected despite removal of the palpable mass for biopsy. With reliable mammography at his disposal, a surgeon may forgo biopsy of palpable masses if they appear unequivocally benign radiographically. This may be a contentious view but undeniably the number of biopsies has decreased in many hospitals since the advent of mammography. Also, the yield of cancer in biopsied material has increased in many hospitals; I ascribe this to reliance on mammography when indications are appropriate (including evaluation of breasts with palpable masses) and to the judicious use of needle aspiration. These changes are not necessarily in absolute numbers but in proportions of patients presenting to their physicians with complaints or suspicious findings, or both, that require investigation. I.S. SIMOR, MD, FRCP(C] Department of radiological sciences Mount Sinai ){ospital Toronto, Ont.
To the editor: Dr. Simor disagrees with my statement that 20% of malignant neoplasms are not detectable by mammography, and states that the figure is 10% or less in most "reputable" series, but does not give a reference for this statement. The references I quoted were an editorial in Surgery, Gynecology and
Obstetrics1 and an article in Annals of Surgery in which 19 928 mammographic studies were carefully reviewed and discussed.2 I most certainly disagree with Dr. Simor's statement that "a surgeon may forgo biopsy of palpable masses if they appear unequivocally benign radiographically". Mammography is not a reliable method of evaluating a mass clinically suspicious of being malignant. To quote Lewis and colleagues,2 "The incidence of false negative reports in proven breast cancer stresses the need for histologic evaluation of suspicious findings on physical examination in spite of normal mammography." The following excerpt from Cohn's editorial1 emphasizes the seriousness of any misconception regarding the reliability of mammography in evaluating lesions clinically suspicious of being malignant: "If on the basis of a negative mammogram, we are to defer biopsy of a solid lesion of the breast, then there is a one in five chance that we are deferring biopsy of a malignant lesion. Therefore, to defer biopsy of a clinically benign solid lesion of the breast which has been called benign on mammography is to take a step backward in the eradication of carcinoma of the breast in our female population. The inherent dangers in a negative biopsy of the breast are almost negligible. However, the danger associated with missing carcinoma of the breast at a stage where it is curable is obvious I do agree with Dr. Simor that mammography is indicated as a prebiopsy procedure to evaluate the remainder of the breast with the palpable mass and the contralateral breast. I have found this a rewarding procedure. I was not suggesting that mammography should not be done when a breast lesion is clinically suspicious of being malignant, but that mammography should not be relied on in the evaluation of the lesion.
Kenya to formulate practical recommendations for an integrated, multidisciplinary, innovative, environmental approach to research into problems related to taeniasis/ cysticercosis and echinococcosis/hydatidosis. The objective was better understanding and the planning of successful control of the two parastic zoonoses. The resulting "Report of the Joint FAQ! UNEP! WHO Consultation on Field Control of Taeniasis and Echinococcosis" is available, free of charge, to all interested parties. Anyone engaged in any capacity in work on these conditions - whether the approach be administrative, laboratory, epidemiologic, environmental or socioeconomic - is invited to communicate with the undersigned to establish a link and to contribute to an urgently needed breakthrough in these problems. Cysticercosis today not only is a serious impediment to the development of a sound livestock industry in developing countries but also is spreading to developed countries owing to tourist traffic, migrant labour forces and influx of students, as well as the unreliability of standard sewage treatment, and thus threatening well established livestock industries. Hydatidosis is still rampant in many parts of the world. Refined diagnostic procedures and nonsurgical means of prevention or treatment, or both, in humans are urgently needed. Similarly, the prevention of animal hydatidosis, which leads to heavy losses of badly needed protein, requires immediate action. A reference library is being established, the principal aim of which is to serve those confronted with the problems of taeniasis/ cysticercosis and echinococcosis/hydatidosis in developing countries. As a contribution to the library, any relevant material (statistical data or scientific reports, published or unpublished) would be gratefully received.
PAUL H. NILOFF, MD Departments of surgery Jewish General and Reddy Memorial hospitals Montreal, PQ
DR. I. MANN Consultant, FAO/UNEP/WHO field control of taeniasis and echinococcosis United Nations environment program P0 Box 30552 Nairobi, Kenya
References I. COHN HE: Mammography in its proper per-
spective (E). Surg Gynecol Obstet 134: 97, 1972 2. Lawis JD, MILssAm JR, SHAFFE.R KA, et al: Which breast to biopsy. Ann Surg 184: 253, 1975
Information needed on taeniasis and echinococcosis To the editor: In June 1976 a joint consultation of experts from the Food and Agriculture Organization (FAQ), the United Nations environment program (UNEP) and the World Health Organization (WHO) was held in Nairobi,
Rupture of splenic artery aneurysm in pregnancy To the editor: Aneurysm of the sple.iic artery was first described in the lite.ature by Beaussier in 1770.' To date about 400 cases have been reported. Splenic artery aneurysm in pregnancy was first reported in 18692 and since then more than 70 cases have been reported. The following case report illustrates the features of this condition. A 32-year-old woman, para 1, gravida III, was admitted to hospital with onset
CMA JOURNAL/JULY 23, 1977/VOL. 117 123
of labour following 39 weeks of gestation. She had had a lower-segment cesarean section a year before because of placenta previa and toxemia of pregnancy. After a short trial of labour the fetal heart rate decreased to 80 beats/mm while the patient complained of sharp abdominal pains and nausea, and vomited. Possible causes were thought to be rupture of the cesarean section scar, placenta abruptio or umbilical cord around the neck of the fetus. Cesarean section was carried out. About 200 ml of blood was present in the pelvis. The lower segment scar, although not torn, was very thin. A live baby with one loop of the cord around the neck was delivered. The placenta was normal in location and was delivered complete. The uterus, tubes and ovaries showed no abnormality. No fresh bleeding was seen. The patient did well until 10 hours postoperatively, when severe abdominal pain developed; she collapsed and died despite cardiopulmonary resuscitative measures. Autopsy revealed a large amount of clotted and free blood in the peritoneal cavity and hilar region of the spleen, extending into the lesser sac of the pentoneum. A ruptured aneurysmal sac 2.5 cm in diameter was found in the splenic artery approximately 10 cm from the artery's origin. Splenic artery aneurysms have been detected at 0.02 to 0.05% of complete autopsies.3'4 Of the 67% in females4 58% were in women of childbearing age. The frequency of rupture of the aneurysm has been reported as 9.2. % In one study 20% of all reported ruptures had occurred during pregnancy,6 but in another study all but 1 of 77 cases of splenic artery aneurysm in pregnancy were associated with rupture.7 Calcified aneurysms rarely rupture; only four such cases have been reported.8 Mortality after rupture has been variously reported as 25 to 46% in nonpregnant patients and 68 to 80% in pregnant women, with a fetal mortality of over 90% . Only three cases were reported in which both mother and child survived.'1 The proportions of ruptures according to stage of the pregnancy have been cited as follows: 1st trimester, 2%; 2nd trimester, 10%; 3rd trimester, 69%; labour, 13%; and puerperium, 6% .12 While the exact cause of splenic artery aneurysm is unknown, pregnancy apparently is important in precipitating rupture. Changes in mucopolysaccharides, hormonal factors, local hemodynamics and strains of labour may be responsible. Toxemia of pregnancy does not seem to be significant. In the reported cases in pregnant women the size of the aneurysm has usually ranged from 2 to 4 cm. Double rupture, as in my patient, occurs in about 20% of pregnant women with splenic artery aneurysms'2 and about 21 % of a gen-
eral group of patients with these aneurysms.4 Diagnosis is extremely difficult. In nonpregnant patients diagnostic measures should include arteriography. Chalmers'3 attributed his success in making the diagnosis preoperatively to the fact that he had just read Ogden's report.'4 The generally accepted treatment of choice for patients of childbearing age discovered to have a splenic artery aneurysm is splenectomy plus excision of the aneurysm. Physicians should be aware of the possibility of splenic artery aneurysm in pregnant women with abdominal pain, for the diagnosis depends ultimately on thinking of the condition. WAN C. Ho, MD, FRcs[C] 20438 Douglas Cres. Langley, BC
References 1. BEAUSSIER M: Sur un an.vrisme de l'art.re splenique dont les parois se sont ossifi6es.
I Med Clin Pharmacol 32: 157, 1770 2. CoRsoN EM: Aneurysm of the splenic artery: rupture and death. M & S Reporter 20: 351, 1869 3. Snai's SG, SPITTEL JA JR, FAIRBAIRN iF ii,
et al: Aneurysms of the splenic artery with special reference to bland aneurysms. Proc
Staff Meet Mayo Cli,, 33: 381, 1958 4. OWENS IC, Cosua. RI: Collective review: aneurysm of splenic artery, including report of 6 additional cases. mt Abstr Surg 97: 313, 1953 5. SPITTEL IA JR, FAIRsAIRN IF ii, KINCAID OW,
et al: Aneurysm of the splenic artery. JAMA
175: 452, 1961
6. VASSALOTTI SB, SCHALLER IA: Spontaneous rupture of splenic artery aneurysm in pregnancy. Report of first known antepartum rupture with maternal and fetal survival.
Obstet Gynecol 30: 264, 1967 7. STANLEY IC, FRY WI: Pathogenesis and clinical significance of splenic artery aneurysms. Surgery 76: 898, 1974 8. WEsTcoI-r IL, ZrrER FMH . Aneurysms of the splenic artery. Surg Gynecol Obstet 136: 541, 1973 9. SCHUG T, RANKIN RP: Rupture of a splenic artery in pregnancy: report of a summary and review of literature. Obstet Gynecol 25: 717, 1965
10. MooRa SW, GUIDA RM, SCHUMACHER HW: Splenic artery aneurysm. Bull Soc mt Chir 29: 210, 1970 11. GissENs D, HEATH D: Ruptured aneurysm of splenic artery in pregnancy (C). Br Med I 4: 103, 1974 12. MACFARLANE IR, THORBJARNARSON B: Rupture of splenic arterial aneurysm during
pregnancy. Am I Obstet Gynecol 95: 1025, 1966
13. CHALMERS IA: Rupture of splenic arterial aneurysm as fatal complication of pregnancy.
Br I Surg 37: 86, 1949 14. OGDEN 1K: Retroperitoneal haemorrhage in pregnancy. Br Med 1 1: 389, 1948
The only tests in common use in North America are those described in the "United States Pharmacopeia XIX" under the heading "Biological tests plastic containers". However, these tests were designed for a different purpose and are not adequate for implant materials. Various organizations and individuals are designing appropriate biocompatibility tests. The bureau has decided to review the present state of the art and try to define what needs to be done in some organized fashion. Standard- writing organizations have been contacted, and Dr. Walter Zingg, Hospital for Sick Children, Toronto, has agreed to organize the study. We invite comments and suggestions from organizations and individuals on the development of methods for testing biocompatibility in the area defined as follows: * Long-term implants, medical and dental (excluding external materials in contact with the skin but including denture materials). * Polymers, both preformed and formed in situ (excluding metals). * Tests of interaction between living tissue and implanted materials (local effects). * Tests of interaction between host and implanted materials (general effects; excluding tests of physical performance but including assessment of elimination of breakdown products of the implant). Comments will be reviewed by the staff of the bureau and by clinical consultants, and may provide a basis for further studies. Letters may be addressed to either of the undersigned. R.W. CAMPBELL, MB, CH B Division of medicine Bureau of medical devices Health and Welfare Canada Environmental Health Centre Tunney's Pasture Ottawa, Ont. KIA 0L2
WALTER ZINOG, MD, ERCs[CJ
Research Institute Hospital for Sick Children 555 University Ave. Toronto, Ont. M5G 1X8
Biocompatibility tests for implant Doctors and torture materials To the editor: The editorial entitled To the editor: The bureau of medical devices of Health and Welfare Canada is charged under the Food and Drugs Act with the responsibility for ensuring that medical devices sold in Canada are safe and effective for their intended use. Biocompatibility of the materials used is one of the major concerns in evaluating devices, particularly implants intended for long-term use.
126 CMA JOURNAL/JULY 23, 1977/VOL. 117
"Doctors, torture and abuse of the doctor-patient relationship" by Dr. Earl M. Cooperman (Can Med Assoc J 116: 707, 1977) was very informative. Dr. Cooperman took as an example of resistance against a dictatorship the underground resistance of Dutch physicians against the "Nazification" of Hol. land during World War II. I have some comments to make on the background of that resistance.
Mammography and xerography To the editor: In his letter "Mammography and xerography" (Can Med Assoc J 116: 712, 1977) Dr. Paul H. Niloff wrote about misconceptions regarding mammography and xerography, which are the same investigation with different recording media. Dr. Niloff emphasized that the role of these radiographic studies is to diagnose nonpalpable neoplasms of the breast. I agree: that is indeed the most important and most spectacular role of mammography. I disagree, however, with his statement that 20% of malignant neoplasms are not detectable by mammography. The false-negative rate is closer to 10% or less in most reputable series. More important, however, mammography is very much indicated as a prebiopsy procedure in the investigation of breasts with one or more palpable masses. If the mass palpated is a neoplasm, one would have to rule out the presence of malignant disease as yet nonpalpable in the contralateral breast - an occurrence that is by no means rare. Even if the mass is benign, a nonpalpable malignant tumour may lurk behind it and may remain undetected despite removal of the palpable mass for biopsy. With reliable mammography at his disposal, a surgeon may forgo biopsy of palpable masses if they appear unequivocally benign radiographically. This may be a contentious view but undeniably the number of biopsies has decreased in many hospitals since the advent of mammography. Also, the yield of cancer in biopsied material has increased in many hospitals; I ascribe this to reliance on mammography when indications are appropriate (including evaluation of breasts with palpable masses) and to the judicious use of needle aspiration. These changes are not necessarily in absolute numbers but in proportions of patients presenting to their physicians with complaints or suspicious findings, or both, that require investigation. I.S. SIMOR, MD, FRCP(C] Department of radiological sciences Mount Sinai ){ospital Toronto, Ont.
To the editor: Dr. Simor disagrees with my statement that 20% of malignant neoplasms are not detectable by mammography, and states that the figure is 10% or less in most "reputable" series, but does not give a reference for this statement. The references I quoted were an editorial in Surgery, Gynecology and
Obstetrics1 and an article in Annals of Surgery in which 19 928 mammographic studies were carefully reviewed and discussed.2 I most certainly disagree with Dr. Simor's statement that "a surgeon may forgo biopsy of palpable masses if they appear unequivocally benign radiographically". Mammography is not a reliable method of evaluating a mass clinically suspicious of being malignant. To quote Lewis and colleagues,2 "The incidence of false negative reports in proven breast cancer stresses the need for histologic evaluation of suspicious findings on physical examination in spite of normal mammography." The following excerpt from Cohn's editorial1 emphasizes the seriousness of any misconception regarding the reliability of mammography in evaluating lesions clinically suspicious of being malignant: "If on the basis of a negative mammogram, we are to defer biopsy of a solid lesion of the breast, then there is a one in five chance that we are deferring biopsy of a malignant lesion. Therefore, to defer biopsy of a clinically benign solid lesion of the breast which has been called benign on mammography is to take a step backward in the eradication of carcinoma of the breast in our female population. The inherent dangers in a negative biopsy of the breast are almost negligible. However, the danger associated with missing carcinoma of the breast at a stage where it is curable is obvious I do agree with Dr. Simor that mammography is indicated as a prebiopsy procedure to evaluate the remainder of the breast with the palpable mass and the contralateral breast. I have found this a rewarding procedure. I was not suggesting that mammography should not be done when a breast lesion is clinically suspicious of being malignant, but that mammography should not be relied on in the evaluation of the lesion.
Kenya to formulate practical recommendations for an integrated, multidisciplinary, innovative, environmental approach to research into problems related to taeniasis/ cysticercosis and echinococcosis/hydatidosis. The objective was better understanding and the planning of successful control of the two parastic zoonoses. The resulting "Report of the Joint FAQ! UNEP! WHO Consultation on Field Control of Taeniasis and Echinococcosis" is available, free of charge, to all interested parties. Anyone engaged in any capacity in work on these conditions - whether the approach be administrative, laboratory, epidemiologic, environmental or socioeconomic - is invited to communicate with the undersigned to establish a link and to contribute to an urgently needed breakthrough in these problems. Cysticercosis today not only is a serious impediment to the development of a sound livestock industry in developing countries but also is spreading to developed countries owing to tourist traffic, migrant labour forces and influx of students, as well as the unreliability of standard sewage treatment, and thus threatening well established livestock industries. Hydatidosis is still rampant in many parts of the world. Refined diagnostic procedures and nonsurgical means of prevention or treatment, or both, in humans are urgently needed. Similarly, the prevention of animal hydatidosis, which leads to heavy losses of badly needed protein, requires immediate action. A reference library is being established, the principal aim of which is to serve those confronted with the problems of taeniasis/ cysticercosis and echinococcosis/hydatidosis in developing countries. As a contribution to the library, any relevant material (statistical data or scientific reports, published or unpublished) would be gratefully received.
PAUL H. NILOFF, MD Departments of surgery Jewish General and Reddy Memorial hospitals Montreal, PQ
DR. I. MANN Consultant, FAO/UNEP/WHO field control of taeniasis and echinococcosis United Nations environment program P0 Box 30552 Nairobi, Kenya
References I. COHN HE: Mammography in its proper per-
spective (E). Surg Gynecol Obstet 134: 97, 1972 2. Lawis JD, MILssAm JR, SHAFFE.R KA, et al: Which breast to biopsy. Ann Surg 184: 253, 1975
Information needed on taeniasis and echinococcosis To the editor: In June 1976 a joint consultation of experts from the Food and Agriculture Organization (FAQ), the United Nations environment program (UNEP) and the World Health Organization (WHO) was held in Nairobi,
Rupture of splenic artery aneurysm in pregnancy To the editor: Aneurysm of the sple.iic artery was first described in the lite.ature by Beaussier in 1770.' To date about 400 cases have been reported. Splenic artery aneurysm in pregnancy was first reported in 18692 and since then more than 70 cases have been reported. The following case report illustrates the features of this condition. A 32-year-old woman, para 1, gravida III, was admitted to hospital with onset
CMA JOURNAL/JULY 23, 1977/VOL. 117 123
of labour following 39 weeks of gestation. She had had a lower-segment cesarean section a year before because of placenta previa and toxemia of pregnancy. After a short trial of labour the fetal heart rate decreased to 80 beats/mm while the patient complained of sharp abdominal pains and nausea, and vomited. Possible causes were thought to be rupture of the cesarean section scar, placenta abruptio or umbilical cord around the neck of the fetus. Cesarean section was carried out. About 200 ml of blood was present in the pelvis. The lower segment scar, although not torn, was very thin. A live baby with one loop of the cord around the neck was delivered. The placenta was normal in location and was delivered complete. The uterus, tubes and ovaries showed no abnormality. No fresh bleeding was seen. The patient did well until 10 hours postoperatively, when severe abdominal pain developed; she collapsed and died despite cardiopulmonary resuscitative measures. Autopsy revealed a large amount of clotted and free blood in the peritoneal cavity and hilar region of the spleen, extending into the lesser sac of the pentoneum. A ruptured aneurysmal sac 2.5 cm in diameter was found in the splenic artery approximately 10 cm from the artery's origin. Splenic artery aneurysms have been detected at 0.02 to 0.05% of complete autopsies.3'4 Of the 67% in females4 58% were in women of childbearing age. The frequency of rupture of the aneurysm has been reported as 9.2. % In one study 20% of all reported ruptures had occurred during pregnancy,6 but in another study all but 1 of 77 cases of splenic artery aneurysm in pregnancy were associated with rupture.7 Calcified aneurysms rarely rupture; only four such cases have been reported.8 Mortality after rupture has been variously reported as 25 to 46% in nonpregnant patients and 68 to 80% in pregnant women, with a fetal mortality of over 90% . Only three cases were reported in which both mother and child survived.'1 The proportions of ruptures according to stage of the pregnancy have been cited as follows: 1st trimester, 2%; 2nd trimester, 10%; 3rd trimester, 69%; labour, 13%; and puerperium, 6% .12 While the exact cause of splenic artery aneurysm is unknown, pregnancy apparently is important in precipitating rupture. Changes in mucopolysaccharides, hormonal factors, local hemodynamics and strains of labour may be responsible. Toxemia of pregnancy does not seem to be significant. In the reported cases in pregnant women the size of the aneurysm has usually ranged from 2 to 4 cm. Double rupture, as in my patient, occurs in about 20% of pregnant women with splenic artery aneurysms'2 and about 21 % of a gen-
eral group of patients with these aneurysms.4 Diagnosis is extremely difficult. In nonpregnant patients diagnostic measures should include arteriography. Chalmers'3 attributed his success in making the diagnosis preoperatively to the fact that he had just read Ogden's report.'4 The generally accepted treatment of choice for patients of childbearing age discovered to have a splenic artery aneurysm is splenectomy plus excision of the aneurysm. Physicians should be aware of the possibility of splenic artery aneurysm in pregnant women with abdominal pain, for the diagnosis depends ultimately on thinking of the condition. WAN C. Ho, MD, FRcs[C] 20438 Douglas Cres. Langley, BC
References 1. BEAUSSIER M: Sur un an.vrisme de l'art.re splenique dont les parois se sont ossifi6es.
I Med Clin Pharmacol 32: 157, 1770 2. CoRsoN EM: Aneurysm of the splenic artery: rupture and death. M & S Reporter 20: 351, 1869 3. Snai's SG, SPITTEL JA JR, FAIRBAIRN iF ii,
et al: Aneurysms of the splenic artery with special reference to bland aneurysms. Proc
Staff Meet Mayo Cli,, 33: 381, 1958 4. OWENS IC, Cosua. RI: Collective review: aneurysm of splenic artery, including report of 6 additional cases. mt Abstr Surg 97: 313, 1953 5. SPITTEL IA JR, FAIRsAIRN IF ii, KINCAID OW,
et al: Aneurysm of the splenic artery. JAMA
175: 452, 1961
6. VASSALOTTI SB, SCHALLER IA: Spontaneous rupture of splenic artery aneurysm in pregnancy. Report of first known antepartum rupture with maternal and fetal survival.
Obstet Gynecol 30: 264, 1967 7. STANLEY IC, FRY WI: Pathogenesis and clinical significance of splenic artery aneurysms. Surgery 76: 898, 1974 8. WEsTcoI-r IL, ZrrER FMH . Aneurysms of the splenic artery. Surg Gynecol Obstet 136: 541, 1973 9. SCHUG T, RANKIN RP: Rupture of a splenic artery in pregnancy: report of a summary and review of literature. Obstet Gynecol 25: 717, 1965
10. MooRa SW, GUIDA RM, SCHUMACHER HW: Splenic artery aneurysm. Bull Soc mt Chir 29: 210, 1970 11. GissENs D, HEATH D: Ruptured aneurysm of splenic artery in pregnancy (C). Br Med I 4: 103, 1974 12. MACFARLANE IR, THORBJARNARSON B: Rupture of splenic arterial aneurysm during
pregnancy. Am I Obstet Gynecol 95: 1025, 1966
13. CHALMERS IA: Rupture of splenic arterial aneurysm as fatal complication of pregnancy.
Br I Surg 37: 86, 1949 14. OGDEN 1K: Retroperitoneal haemorrhage in pregnancy. Br Med 1 1: 389, 1948
The only tests in common use in North America are those described in the "United States Pharmacopeia XIX" under the heading "Biological tests plastic containers". However, these tests were designed for a different purpose and are not adequate for implant materials. Various organizations and individuals are designing appropriate biocompatibility tests. The bureau has decided to review the present state of the art and try to define what needs to be done in some organized fashion. Standard- writing organizations have been contacted, and Dr. Walter Zingg, Hospital for Sick Children, Toronto, has agreed to organize the study. We invite comments and suggestions from organizations and individuals on the development of methods for testing biocompatibility in the area defined as follows: * Long-term implants, medical and dental (excluding external materials in contact with the skin but including denture materials). * Polymers, both preformed and formed in situ (excluding metals). * Tests of interaction between living tissue and implanted materials (local effects). * Tests of interaction between host and implanted materials (general effects; excluding tests of physical performance but including assessment of elimination of breakdown products of the implant). Comments will be reviewed by the staff of the bureau and by clinical consultants, and may provide a basis for further studies. Letters may be addressed to either of the undersigned. R.W. CAMPBELL, MB, CH B Division of medicine Bureau of medical devices Health and Welfare Canada Environmental Health Centre Tunney's Pasture Ottawa, Ont. KIA 0L2
WALTER ZINOG, MD, ERCs[CJ
Research Institute Hospital for Sick Children 555 University Ave. Toronto, Ont. M5G 1X8
Biocompatibility tests for implant Doctors and torture materials To the editor: The editorial entitled To the editor: The bureau of medical devices of Health and Welfare Canada is charged under the Food and Drugs Act with the responsibility for ensuring that medical devices sold in Canada are safe and effective for their intended use. Biocompatibility of the materials used is one of the major concerns in evaluating devices, particularly implants intended for long-term use.
126 CMA JOURNAL/JULY 23, 1977/VOL. 117
"Doctors, torture and abuse of the doctor-patient relationship" by Dr. Earl M. Cooperman (Can Med Assoc J 116: 707, 1977) was very informative. Dr. Cooperman took as an example of resistance against a dictatorship the underground resistance of Dutch physicians against the "Nazification" of Hol. land during World War II. I have some comments to make on the background of that resistance.
