1283

These

two

with very

patients,

severe

atopic dermatitis, had

benefit from 12 or 14 week courses ofIFN-et at 3

x

no

106 units thrice

weekly. Department of Dermatology, University of Glasgow.

Glasgow G12 8QQ,

RONA M. MACKIE

UK

G, Rousset F, de Vries JE. Alpha-interferon treatment of patients with hyper-IgE syndrome. Lancet 1989; ii: 1384. 2. Thompson RA, Kumararatne DS. Hyper-IgE syndrome and H2-receptor blockade. Lancet 1989; ii: 630. 3. Lever RS, Lesko M, MacKie RM, Parrott DMV. Natural killer cell activity in atopic dermatitis. Clin Allergy 1984; 14: 483-88. 4. Kusiami NT, Trentin JJ. Natural cell mediated cytotoxic activity in the peripheral blood of patients with atopic dermatitis. Arch Dermatol 1982; 118: 568-71. 1. Souillet

A brain

transplant that works

SIR,-Your editorial (Feb 24, p 445) refers to Lindvall and case1 as "the first unequivocal account of a successful human brain transplant". The first fetal homotransplants in man were done in Mexico on Sept 12, 1987, in two patients with Parkinson’s disease, and an "unequivocal account" of bilateral improvement in motor function 3 months after the procedure was

colleagues’

published in January, 1988.2 Follow-up reports on these and later cases have been published (eg, refs 3-5). The report given by our Swedish colleagues, demonstrating the viability of the grafted fetal neurons by positron emission tomography, is a very important contribution but those working in brain transplantation are not in a position, on current knowledge, to deny the usefulness of grafts of autologous adrenal medulla into brain. This procedure, still under development, does not require the use of risky immunosuppressive therapy. Department of Experimental Neurology and Neurosurgery, Centro Medico Siglo XXI, 143000 Mexico City, Mexico

REBECCA FRANCO-BOURLAND

1 Lindvall O, Brundin P, Widner H, et al. Grafts of fetal dopamine neurons

survive and improve motor function in Parkinson’s disease. Science 1990; 247: 574-77. 2. Madrazo I, Leon V, Torres C, et al. Transplantation of fetal substantia nigra and adrenal medulla to the caudate nucleus in two patients with Parkinson’s disease.

N Engl J Med 1988; 318: 51. 3. Madrazo I, Franco-Bourland R, Aguilera M, Ostrosky-Solis F. Hispanic registry of graft procedures for Parkinson’s disease. Lancet 1989; ii: 751. 4. Madrazo I, Franco-Bourland RE, Ostrosky F, Aguilera M, Candelas JA. Human brain transplantation of adrenal medullary and fetal brain tissue for functional restoration in the diseased brain (clinical experience in Parkinson’s disease). In: Hatase O, Wang JH, eds. Bioinformatics: Proceedings of the International Symposium on Information, Transduction, and Processing in Biological Systems from Cell to Whole Body. Amsterdam: Elsevier, 1989: 289-96. 5. Madrazo I, Garcia L, Torres C, et al. Initial neurotransplants in humans. In: Koller WC, Paulson G, eds. Therapy of Parkinson’s disease. New York. Marcel Dekker, 1990: 473-99.

Evening primrose oil

and

eczema

SiR,—In reply to our letter questioning evidence for improvement atopic eczema with evening primrose oil (EPO) (March 17, p 667), Dr Horrobin and Dr Stewart (April 7, p 864) cite only part of a statement and thus ignore a major point in our argument. In a placebo-controlled trial of any treatment it is essential to compare active and placebo groups at the end of the study period and not just before and after treatment values for the active group. The testing of the null hypothesis requires analysis of the difference between two population means. One triaP referred to by Horrobin and Stewart illustrates the point. In this trial of EPO (’Epogam’) in childhood atopic eczema with 12 patients in both groups the clinical scores were 25-5 (SD 6-2) before and 18-3 (9-0) after EPO and 21-5 (4-7) before and 20-8 (6-6) after placebo. The pre and post values for EPO were significantly different, whilst a similar comparison for the placebo patients was not. However, in the only meaningful comparison-for active and placebo groups at the end of the trial-there is no difference. The groups were not well matched; the of

were

comparable.

We stated (in full) that "no published trial yields a significant advantage of epogam over placebo in direct comparisons of dermatologists’ assessment". Epogam may, as Harrison and Stewart claim, have been more thoroughly studied than other treatments. However, these studies do not give any confidence that this novel treatment is any better than placebo. Department of Dermatology, Royal Victoria Infirmary,

G. R. SHARPE P. M. FARR

Newcastle upon Tyne NE1 4LP, UK

PL, Masi M, et al. Evening primrose oil (Efamol) in the treatment of children with atopic eczema. Drugs Exp Clin Res 1987; 14: 291-97. 2. Schalin-Karrila M, Mattila L, Jansen CT, Uotila P. Evening primrose oil in the treatment of atopic eczema: effect on clinical status, plasma phospholipid fatty acids and circulating blood prostaglandins. Br J Dermatol 1987; 117: 11-19. 3. Altman DG, Doré CJ. Randomisation and baseline comparisons in clinical trials. Lancet 1990; 335: 149-53. 4. Wnght S, Burton JL. Oral evening-primrose-seed oil improves atopic eczema. Lancet 1982; ii: 1220-22. 1. Bordom A, Biagi

Night myopia

IGNACIO MADRAZO

Department of Biochemistry, Institute Nacional de la Nutricion Salvador Zubiran, Mexico City

EPO group was almost 20% more severely affected than the placebo group. In the trial by Schalin-Karrila et al2 the inappropriate analysis of itch scores showed a significant result for the EPO treated group. However, the appropriate analysis of itch score at the end of the treatment period showed no significant difference between epogam and placebo. Again, the EPO group was more severely affected; the pre-trial score for itch was 50% greater in the epogam group. Such a large difference is important because of the greater scope for improvement during treatment in the epogam group. A recent paper in The Lancet3 on the statistical analysis of clinical trials underlines the necessity for baseline comparisons, and on that criterion neither of the above trials has been adequately analysed. The third trial cited by Horrobin and Stewart only presented changes from baseline’ and there is no indication that the groups

SIR,-A judgment at Durham Crown Court, in R vs Smith (Jan 12, 1990), will be of interest to ophthalmologists and to doctors providing ophthalmic services. A motorcyclist who had killed a pedestrian was convicted of driving without due care and attention, but was acquitted on the more serious offence of causing death by reckless driving because expert evidence stated that he had suffered from night myopia, of which he was not aware. He had been prescribed glasses for myopia but was not wearing them at the time of the accident. refers to a condition in which near-sightedness levels of illumination fall; it remains controversial despite having been recognised for two hundred years. The increase in myopia in the dark has been attributed to an alteration of spherical or chromatic aberration or to lenticular and accommodative changes.Lately, laser speckle optometry and dark retinoscopy have been used to measure the degree of myopia. The need for correction of night myopia in the individual remains difficult. There may be great variation between visits, and further variability may be induced by psychological and emotional stress. Bad weather and changes in luminance from one area to another will also affect the correction required. Hope and Rubin’ point out that although optical correction may help with visual blurring in the dark, it may be necessary to provide for a range of different conditions. This severely reduces the practicality of converting measurements obtained during an assessment of refraction into a helpful prescription. It would be more useful for all drivers to be made aware of the possibility of night myopia so that they can modify their driving habits in poor light. They should be encouraged to wear their distance glasses whenever they drive-a point which the court might have given more weight to in the above

"Night myopia"

increases

as

case.

Departments of Ophthalmology and Clinical Pharmacology, St Thomas’ Hospital,

C. B. JAMES D. R. TREW

London SE1 7EH, UK 1. Hope

GM, Rubin ML. Night

myopia Surv

Ophthalmol 1984; 29:

129-36.

Evening primrose oil and eczema.

1283 These two with very patients, severe atopic dermatitis, had benefit from 12 or 14 week courses ofIFN-et at 3 x no 106 units thrice wee...
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