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Research into scoliosis has been hampered by themultiplicity of disciplines concerned. Orthopaedicsurgeons are to the fore, but paediatricians, neurolo-gists, and even cardiologists and thoracic surgeonsplay their part. One difficulty, therefore, is thatworkers do not always have an obvious claim on anyparticular fund. On Nov. 14-16 a scoliosis working-party-the first of its kind-is to meet in Chicago.It has been planned jointly by the National Institutesof Health, the American Academy of OrthopedicSurgeons, and the Scoliosis Research Society, and thehope is to " identify areas in which investigationwould be of major importance to the better under-standing, prevention and treatment of scoliosis ".

Scoliosis patients are fortunate in that orthopaedicsurgeons have made much progress in treatment

despite ignorance of the underlying cause. Withfurther surgical advances, indeed, causation maybecome increasingly unimportant; but there is a longway to go, and now that the disorder is being thoughtof in general rather than purely orthopaedic terms thereis a strong case for study in special centres. Perhapsthe immediate goal of all those concerned with thisdistressing deformity of children ought to be exactlythe one set down for the Chicago working-party.

LITTLE LIGHT ON PHOTOTHERAPY

THE fetus handles bilirubin by transferring the

major load across the placenta. At birth there is animbalance between the rate of bilirubin productionand the ability of the immature liver to clear thebilirubin into bile. The situation is aggravated ifthere is haemolysis or if the infant is premature.Lipid-soluble unconjugated bilirubin diffuses readilyacross the cell membrane and causes damage, probablyby interfering with cellular respiration. Normally ittakes about two weeks for the infant liver to maturesufficiently for effective handling of the bilirubin.1The rise in serum unconjugated bilirubin concentra-tions may have to be limited, and three methods arein use-exchange transfusion, phenobarbitone therapy,and phototherapy. In many paediatric departmentsphototherapy has been adopted both for prophylaxisof hyperbilirubinaemia and for treatment of existingjaundice, particularly in low-birthweight infants. Inmost infants 12-24 hours of exposure to light is

probably enough to prevent the bilirubin rising above13 mg. per 100 ml. 2 Elliott et al. suggest that photo-therapy should be started when the bilirubin reaches12 mg. per 100 ml. but that if the birthweight isbelow 1500 g. the starting level should be 10 mg.per 100 ml. Although light therapy is relativelyineffective in managing the jaundice of rhesus haemo-lytic disease of the newborn, it may have a role inABO incompatibility and can reduce the need forexchange transfusions. 4,5 Which type of fluorescent

lamp is most useful remains to be determined, and atpresent broad-spectral-output (" daylight "), standard

1. Schmid, R. New Engl. J. Med. 1972, 287, 703.2. Tabb, P. A., Inglis, J., Savage, D. C. L., Walker, C. H. M. Lancet,

1972, ii, 1211.3. Elliott, E., Moncrieff, M. W., George, W. H. S. Archs Dis. Childh.

1974, 49, 60.4. Sisson, T. R. C., Kendall, N., Glauser, S. C., Knutson, S., Bunya-

viroch, E. J. Pediat. 1971, 79, 904.5. Kaplan, E., Herz, F., Scheye, E., Robinson, L. D., Jr. ibid. p. 911.

blue, and special narrow-spectrum blue lamps are

available.While the clinical status of phototherapy has

become more settled, its mode of action remains

relatively obscure. Exposure of bilirubin to the blueportion of the spectrum (420-490 nm.) inducesoxidation of the bilirubin; but the chemical nature andbiological effects of these photo-oxidative-degradationproducts are largely unrecognised, and thereforedoubts persist about safety. The products are

apparently more polar than unconjugated bilirubin andhence more readily excreted into bile and urine. In an

attempt to understand the process in vivo, Lund andJacobsen 6 have studied the bile aspirated from theduodenum of 15 newborn infants undergoing photo-therapy. They observed a striking change in thecolour of the bile from golden yellow to brownishblack. Unfortunately they were unable to characterisethese dark pigments. Surprisingly there was an

increase in the excretion of unconjugated bilirubinin the bile. Further work by Lund and Jacobsenshowed that this added deconjugation was not mediatedby increased beta-glucuronidase activity in bile.’ In

theory, phototherapy might directly influence theexcretion of unconjugated bilirubin by the liver; a

more plausible explanation is supplied by the in-vitroinvestigations of Garbagnati and Manitto,8 whoidentified a new class of photoderivatives whenbilirubin was irradiated in the presence of substances

containing hydroxyl or sulphhydryl groups. The

products are diazo positive and have electronic spectrasimilar to that of unconjugated bilirubin. It is possiblethat if any of these pigments are formed in vivo

during phototherapy they might be responsible foran apparent increase in the biliary concentration ofunconjugated bilirubin. Further investigations ofthis would be welcome. More information is neededabout bile-flow, biliary proteins, and other components,although these are unlikely to be influenced to thesame extent as the bile pigments. It is a reflection ofthe complexity of the problem that some sixteen yearsafter the introduction of phototherapy we still knowso little about its effects.

6. Lund, H. T., Jacobsen, J. ibid. 1974, 85, 262.7. Lund, H. T., Jacobsen, J. ibid. p. 268.8. Garbagnati, E., Manitto, P. ibid. 1973, 83, 109.

PRICE OF THE LANCET

THE black border to this editorial is

symbolic. On Jan. 1, 1975, Adam Street,London, is to witness a mournful ceremony-that of the raising of the subscription-rates.For the London edition of The Lancet, thiswill be the first such occasion in four in-

creasingly expensive years. The new annualrates will be:

Standard E12

For newly qualified doctors (within five

years of provisional registration) E6 6For medical students E3.50