1976, British Journal of Radiology, 49, 739
AUGUST 19',
Correspondence TABLE II SUGGESTED NEW PREFIXES FOR SI UNITS
2 3 6 9 12 15 18
Negative
Positive
Power of 10 Name (a)
Name (b)
plu-Do plu-Tri plu-Sexa plu-Nona plu-Dodeka plu-Pentdeka plu-Octdeka
Bi-pos Tri-pos Hexa-pos Nona-pos Dodeka-pos Pentdeka-pos Octdeka-pos
Symbol DorB
T SorH N DD PD OD
suggested symbols relate systematically to the names, and present no problems to typists or printers. It is also clear that additional names can be easily formed on the same principles without requiring a secret conclave of wordsmiths! For simplicity in writing when not employing symbols only, the terms could be used without the syllables plu, pos, etc., indicating positive powers by a capital initial, negative ones by a lower case. It may be said that it would be difficult to replace terms now in common use, such as hecto, centi, milli, kilo, micro and mega, with any of these suggested here. While this may be true to some extent in popular usage, it should not be so in scientific usage where new agreed terms have frequently displaced, or are in the process of replacing older, often well-established ones, such as Fahrenheit, pound (-force) per square inch, or even millicurie, etc. In any case, for names denoting powers of ± 6 or greater the existing terms have hardly entered popular usage, and a switch to new ones could readily be accomplished. It will be seen that no new terms are suggested to replace "deca" and "deci", and these could well be dropped from scientific usage altogether. Concerning the symbols, it will be noted that n retains its meaning, and that the only symbols already in use with a new meaning would be T and h, the latter replacing the symbol for "micro" which at present has also the undesirable feature of being the only one requiring a Greek letter. It is clear that the adoption of a mnemonic system of prefixes for SI units such as suggested here would be highly desirable. Yours, etc., P. M. PFALZNER.
The Ontario Cancer Foundation (Ottawa Clinic) Ottawa, Canada.
THE EDITOR—SIR, VAN BUCHEM'S DISEASE
I found Dr. Owen's article (B.J.R., 1976) most interesting, but Table II is a little misleading. The skull is sclerotic in more than half the reported cases of diaphyseal dysplasia; sparing of the mandible and facial bones in osteopetrosis is relative rather than absolute. Yours etc., D. SHAW
Department, Gower Street, London WC1E6AU REFERENCE OWEN, R. H., 1976. Van Buchem's disease (hyperostosis corticalis generalisata). British Journal of Radiology, 49, 126-132.
Name (a)
Name (b)
mi-do mi-tri mi-sexa mi-nona mi-dodeka mi-pentdeka mi-octdeka
bi-neg tri-neg hexa-neg nona-neg dodeka-neg pentdeka-neg octdeka-neg
Symbol dorb t sorh n dd pd od
THE EDITOR—SIR, BONE CHANGES IN INTRAHEPATIC BILIARY ATRESIA
We were very interested in reading the article entitled "Bone Changes in intrahepatic biliary atresia" (Raghavendra and Genieser, 1976). However, this report concerns only part of the changes which have already been reported in this syndrome. Indeed, vertebral anomalies have also been observed. The few cases found in the literature by the authors is also very surprising (Alagille et al., 1975). Yours, etc., D. ALAGILLE.
Unite de Recherche d'Hepatologie Infantile, I.N.S.E.R.M.U 56, Hopital d'Enfants, 94270 Bicetre, France. REFERENCES ALAGILLE, D., ODIEVRE, M., GAUTIER, M., and DOMMER-
GUES, J. P., 1975. Hepatic ductular hypoplasia associated with characteristic facies, vertebral malformations, retarded physical, mental, and sexual development, and cardiac murmur. The Journal of Pediatrics, 86, 663—71. RAGHAVENDRA, B. N., and
GENIESER, N. B., 1976.
Bone
changes in intrahepatic biliary atresia. British Journal of Radiology, 49,179-181.
THE EDITOR—SIR, MUST RADIOLOGISTS DO ALL THE REPORTING?
I was pleased to see this complex and somewhat "sticky" problem brought into the open. It was discussed in the American literature a few years ago (Addington et al., 1972; Correspondence, 1972). The well-known arguments noted by Dr. Emrys-Roberts (1975) and many other equally good jints will not be repeated here. personally believe the problem is being looked at too rowly. If one is trying to utilize radiologists' time fciently, then ALL of the duties which they traditionally Form in running X-ray departments must be considered ether. Only then can a comprehensive analysis be made !>rder to decide where to "cut corners" while doing the st potential harm to the patients. For instance, to start wjth, unecessary X-rays must be discouraged (there are other d reasons for this too) and we all know that many are Iquested every day (Middlemass, 1971), especially skull 1ms (Roberts and Shopfner, 1972; Bell and Loop, 1971; layes and Shopfner, 1973). Then, perhaps in some smaller centres, it would be more practical to eliminate time consuming special procedures (they could be done in more specialized centres). Also, as is now being tried in the United States and Japan, specially trained radiographers might be allowed to perform some screening procedures (Lewicki, 1975). Professional, non-physician departmental
739
AUGUST 19',
Correspondence TABLE II SUGGESTED NEW PREFIXES FOR SI UNITS
2 3 6 9 12 15 18
Negative
Positive
Power of 10 Name (a)
Name (b)
plu-Do plu-Tri plu-Sexa plu-Nona plu-Dodeka plu-Pentdeka plu-Octdeka
Bi-pos Tri-pos Hexa-pos Nona-pos Dodeka-pos Pentdeka-pos Octdeka-pos
Symbol DorB
T SorH N DD PD OD
suggested symbols relate systematically to the names, and present no problems to typists or printers. It is also clear that additional names can be easily formed on the same principles without requiring a secret conclave of wordsmiths! For simplicity in writing when not employing symbols only, the terms could be used without the syllables plu, pos, etc., indicating positive powers by a capital initial, negative ones by a lower case. It may be said that it would be difficult to replace terms now in common use, such as hecto, centi, milli, kilo, micro and mega, with any of these suggested here. While this may be true to some extent in popular usage, it should not be so in scientific usage where new agreed terms have frequently displaced, or are in the process of replacing older, often well-established ones, such as Fahrenheit, pound (-force) per square inch, or even millicurie, etc. In any case, for names denoting powers of ± 6 or greater the existing terms have hardly entered popular usage, and a switch to new ones could readily be accomplished. It will be seen that no new terms are suggested to replace "deca" and "deci", and these could well be dropped from scientific usage altogether. Concerning the symbols, it will be noted that n retains its meaning, and that the only symbols already in use with a new meaning would be T and h, the latter replacing the symbol for "micro" which at present has also the undesirable feature of being the only one requiring a Greek letter. It is clear that the adoption of a mnemonic system of prefixes for SI units such as suggested here would be highly desirable. Yours, etc., P. M. PFALZNER.
The Ontario Cancer Foundation (Ottawa Clinic) Ottawa, Canada.
THE EDITOR—SIR, VAN BUCHEM'S DISEASE
I found Dr. Owen's article (B.J.R., 1976) most interesting, but Table II is a little misleading. The skull is sclerotic in more than half the reported cases of diaphyseal dysplasia; sparing of the mandible and facial bones in osteopetrosis is relative rather than absolute. Yours etc., D. SHAW
Department, Gower Street, London WC1E6AU REFERENCE OWEN, R. H., 1976. Van Buchem's disease (hyperostosis corticalis generalisata). British Journal of Radiology, 49, 126-132.
Name (a)
Name (b)
mi-do mi-tri mi-sexa mi-nona mi-dodeka mi-pentdeka mi-octdeka
bi-neg tri-neg hexa-neg nona-neg dodeka-neg pentdeka-neg octdeka-neg
Symbol dorb t sorh n dd pd od
THE EDITOR—SIR, BONE CHANGES IN INTRAHEPATIC BILIARY ATRESIA
We were very interested in reading the article entitled "Bone Changes in intrahepatic biliary atresia" (Raghavendra and Genieser, 1976). However, this report concerns only part of the changes which have already been reported in this syndrome. Indeed, vertebral anomalies have also been observed. The few cases found in the literature by the authors is also very surprising (Alagille et al., 1975). Yours, etc., D. ALAGILLE.
Unite de Recherche d'Hepatologie Infantile, I.N.S.E.R.M.U 56, Hopital d'Enfants, 94270 Bicetre, France. REFERENCES ALAGILLE, D., ODIEVRE, M., GAUTIER, M., and DOMMER-
GUES, J. P., 1975. Hepatic ductular hypoplasia associated with characteristic facies, vertebral malformations, retarded physical, mental, and sexual development, and cardiac murmur. The Journal of Pediatrics, 86, 663—71. RAGHAVENDRA, B. N., and
GENIESER, N. B., 1976.
Bone
changes in intrahepatic biliary atresia. British Journal of Radiology, 49,179-181.
THE EDITOR—SIR, MUST RADIOLOGISTS DO ALL THE REPORTING?
I was pleased to see this complex and somewhat "sticky" problem brought into the open. It was discussed in the American literature a few years ago (Addington et al., 1972; Correspondence, 1972). The well-known arguments noted by Dr. Emrys-Roberts (1975) and many other equally good jints will not be repeated here. personally believe the problem is being looked at too rowly. If one is trying to utilize radiologists' time fciently, then ALL of the duties which they traditionally Form in running X-ray departments must be considered ether. Only then can a comprehensive analysis be made !>rder to decide where to "cut corners" while doing the st potential harm to the patients. For instance, to start wjth, unecessary X-rays must be discouraged (there are other d reasons for this too) and we all know that many are Iquested every day (Middlemass, 1971), especially skull 1ms (Roberts and Shopfner, 1972; Bell and Loop, 1971; layes and Shopfner, 1973). Then, perhaps in some smaller centres, it would be more practical to eliminate time consuming special procedures (they could be done in more specialized centres). Also, as is now being tried in the United States and Japan, specially trained radiographers might be allowed to perform some screening procedures (Lewicki, 1975). Professional, non-physician departmental
739
