875

SIR,-Dr Saari-Kemppainen

and

colleagues (Aug 18,

p

387)

suggest that their controlled trial justifies systematic one-stage ultrasound screening. They do not comment on the 20 miscarriages in the screened group compared with none in the controls. A randomised prospective trial from Michigan found that preterm labour

was more

than doubled in

a

group that had

Bodegard G, Fyro K, Larsson A. Psychological reactions in 102 families with a newborn who had a falsely positive screening test for congenital hypothyroidism. Acta Paediatr Scand 1983; suppl 304 1-21. 3. Fyro K, Bodegard G Difficulties in psychological adjustment to a new neonatal screening programme. Acta Paediatr Scand 1988, 77: 226-31. 4. Green JM Calming or harming? A critical review of psychological effects of fetal diagnosis on pregnant women. London Galton Institute, 1990. 5 Delight E, Goodall J. Love and loss conversations with parents of babies with spina bifida managed without surgery 1971-1981 Devel Med Child Neurol 1990; suppl 2.

Risks of antenatal ultrasound

weekly

61: 1-55

ultrasound compared with those who had pelvic examinations

(52% vs 25%), and suggested that ultrasonography may predispose to labour in some way, perhaps via bladder distension: "We see many patients at risk for preterm labour who report much more frequent contractions when they have a full bladder; in fact when they void the uterine activity is then reduced". At least 250 screened women presumably experienced the anxiety of an early diagnosis of placenta praevia although only 4 had the condition at delivery. We do not know whether the effects on these women were negligible, as Saari-Kemppainen et al think. Nor are we given evidence to support the assertion that reassurance from screening was the cause of reduced antenatal visits. Ultrasonography does not "reduce the rate of postmaturity"; it lowers the rate of false-positive diagnosis of postmaturity. Ultrasonography "corrected" the expected date of delivery by 10 or more days in 11.5% of women. Alterations are not necessarily corrections, for women sure of their dates. We get indignant letters from women who know the date of conception and are proved right, the obstetricians having insisted that the ultrasound scan could not be wrong. We are not told what examinations, if any, were done on the 11 screened fetuses aborted for malformations, or how accurate their scan result proved to be (in 10 of 30 cases the suspected abnormality disappeared later). The stress from a false-positive finding may be far from negligible and could be long lasting. Some families given a false-positive diagnosis of congenital hypothyroidism were adversely affected; one-fifth were still anxious 6-12 months later and some had unresolved problems at 4 years.3 None of the control women chose to terminate pregnancy with a malformed fetus, but we are not told the number of cases in which malformation was suspected, at what stage, or how many of the 10 fatal malformations had been previously detected. Therefore we cannot tell how far the lower perinatal mortality in the screened group stems from the higher detection rate of malformation, and how much it may also have been affected by different decisions in women in the two groups. If information were given differently to screened and control women, this could affect the decisions made. As Green, reviewing the effects of fetal diagnosis, concludes: "The concept of free choice is a dubious one at the best of times. In the case of pregnant women the social pressures ... to teminate an affected pregnancy are considerable."4 The "hard" benefit of the screening in this study was a reduction, not in mortality of babies, but in perinatal mortality statistics, because some women chose to terminate pregnancy, as they have every right to do. For many families it will be a sad choice, but the best one. However, a wise and compassionate study by Delight and Gooda1l5 of views of parents of children with untreated spina bifida, suggests to us that for at least some families and some conditions, and given the right professional support, continuing the pregnancy could bring a better outcome for the family. The disadvantage is that their decisions would result in poorer perinatal and infant mortality statistics. Whose criteria are we to use for "cost" and "benefit"? We suggest that users of obstetric services can make informed choices only if medical research is accompanied by adequate independent social science research. Oxford

JEAN ROBINSON

Association for Improvements in the Maternity Services, 21 Iver Lane Iver, Bucks SL09LH, UK

BEVERLEY A. L. BEECH

1

Lorenz RP, Comstock CH, Bottoms SF, Marx SR. Randomized prospective trial comparingultrasonographyandpelvicexaminationforpretermlaborsurveillance. Am JObstet

Gynecol 1990, 162: 1603-09

Multicentre study of antenatal calyceal dilatation detected by ultrasound SIR,-Dr Newell and colleagues report (Aug 11, p 372) on the significance of antenatal calyceal dilatation detected by

clinical

ultrasound. We agree that the importance of these findings remains unclear and can only be elucidated by a large collaborative study.

Early in 1990 we began a multicentre study of 14 hospitals which routinely offer fetal ultrasound between 18 and 20 weeks’ gestation, for the detection of fetal anomalies. Our aim was to establish the incidence, natural history, and clinical significance of mild dilatation of the fetal renal pelvis. We anticipate recruitment of patients for 2 years, and the study should include at least 100 000 deliveries. So far, few of the affected fetuses have been born. However, the incidence of fetal calyceal dilatation seems to be about 0 62 per 100 deliveries (a total of 84 in 13 500), and clinically significant renal abnormality can be found in the newborn baby when the prenatal dilatation is as little as 5 mm (mean anteroposterior and transverse diameters) in the second trimester. We would welcome the comments and collaboration of other units with such screening programmes, in order to attempt to resolve one of the more common dilemmas of prenatal ultrasound. Department of Paediatric Genetics. Institute of Child Health, London WC1 N 1EH, UK Department of Obstetrics and Gynaecology, King’s College Hospital, London SE5

Tumour

L. S. CHITTTY M. E. PEMBREY P. M. CHUDLEIGH S. CAMPBELL

imaging with labelled liposomes

SIR,-Professor Presant and colleagues (June 2, p 1307) report the

scintigraphic imaging with indium-111-labelled of liposomes Kaposi’s sarcomas in AIDS patients. It should be remembered that liposomes also accumulate in septic and aseptic inflammatory lesions.l,2 Thus, results of liposome-scanning could be misleading, especially in AIDS patients where the coincidence of Kaposi’s sarcomas and inflammatory lesions is not unusual. However, we agree with Presant et al that labelled liposomes might offer a new approach to tumour diagnosis and therapy. With indium-lll-labelled liposomes, we have investigated 17 men and 7 women (age range 36-66 years) with known malignant disease, to prove the diagnostic value of liposome scanning in the staging and follow-up of different malignant tumours. 6 of the patients were receiving antitumoural chemotherapy at the time of liposome scanning. Liposomes were radiolabelled with 18.5-37 MBq indium-111 (’VesCan’, Vestar, San Dimas, California). Scintigraphic images were taken 24 h and 48 h post-infection in all patients. In addition, early images (30 min and 6 h) and delayed images (72 h) were obtained in selected patients. 29 different sites of tumour disease were proven by surgery, radiography, computed tomography, ultrasound, and magnetic resonance imaging in 23 patients. 17 of the 29 lesions (59%) were imaged by liposome scanning. "True positive" results of liposome scanning were obtained in patients with oropharyngeal carcinomas (12 of 18 lesions), malignant melanomas (2 of 2), bronchiogenic carcinomas (2 of 5), and metastasising eosinophilic thyroid carcinoma (1 of 2). Thus, liposome scanning failed to detect 6 lesions in patients with oropharyngeal carcinomas (3 in patients having chemotherapy), 3 lesions in patients with bronchiogenic carcinomas (all in patients under chemotherapy), 2 lesions in a non-Hodgkin-lvmphoma patient (receiving chemotherapy), and 1 lesion in a patient with thyroid carcinoma. "False positive" successful

Multicentre study of antenatal calyceal dilatation detected by ultrasound.

875 SIR,-Dr Saari-Kemppainen and colleagues (Aug 18, p 387) suggest that their controlled trial justifies systematic one-stage ultrasound screen...
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