Photo de Lyon

Gilbert, dit Gilles (Camille) LYON (b. 1921) was born in Mulhouse, a city of the Haut-Rhin, an Alsatian department in France.  His father had been a lawyer and legal counselor of the French Ministry of Foreign Affairs.  His mother belonged to an Alsatian family of industrialists.  He attended high school in Paris.

Lyon started medical school in Paris (which includes college in continental Europe) in 1940 and two years later attempted to apply for the Externat des Hôpitaux, a rotating internship for the best young medical students, awarded on a competitive basis.  However, he was prevented from applying to the Externat by the "laws of exception" promulgated by the Vichy government against those of Jewish origin.  In February 1943 he crossed the Spanish border and, upon reaching England, volunteered for the Forces Françaises Libres (FFL) of General Charles de Gaulle.  He spent one year at Ribbesford in the military school of the FFL. As a lieutenant, Lyon served in the Second Armoured Division (the famous "Seconde D.B." of General Leclerc) until the Liberation and received the French War Cross.

Lyon resumed his medical training after the war.  As was the custom in France for the best students, medical school was combined with an internship (« externat ») and afterwards, a residency program (« internat »).  Among the chiefs who had an important impact on his training and career were Raymond Garcin at the Hôpital de la Salpêtrière, Julien Marie and Robert Debre at the Hôpital des Enfants Malades, and Stéphane Thieffry at the Hôpital des Enfants Malades and later at the Hôpital des Enfants Assistés (also called the Hôpital Saint Vincent de Paul).  He graduated with a doctorate in medicine and at the same time as a licensed pediatrician in 1955 from the University of Paris.  It was the tradition in France to delay the official graduation as M.D. until completion of both residency and specialty training.  Lyon graduated three years later than many of his high school classmates, due to his service in the army during the war.

<> Several persons familiar with events at that time led me to understand that the postwar medical establishment did not treat former young members of the Resistance with special attention and sometimes "penalized" them by not taking into account for the age limit of the "concours," the time spent in the army.  His thesis was entitled "Contribution à l'étude des hémiplégies survenant au cours des premiers mois de la vie" ("Contribution on the Study of Hemiplegia Following the First Months of Life").  This early publication displayed many of the qualities of his subsequent works: a comprehensive examination of the material, deliberate in thought, original, and written in a style that was extremely concise and clear. After publication, he disdained any effort to advertise his own publications in the professional community turned his mind to his current work. The quality of his thesis, a model of clinical research, was recognized by the 1956 Thesis Award of the French National Academy of Medicine and later by publication in the international literature (Lyon, 1961).
<>From 1955 until 1962, Lyon completed his training in neuropathology and occupied several positions as clinical and research fellow in Paris and in Boston : 1955-57; chef de clinique (in France, this term means clinical fellow; in the rest of Europe, this term means associate chief of service), Hôpital des Enfants Malades, Paris; 1957-58: clinical and research fellow, Massachusetts General Hospital, Boston; 1959-62; Chargé de Recherches (research associate), Institut National de la Santé et de la Recherche Médicale (INSERM), Paris.  This period was crucial for his professional development, especially his contact and neuropathology training with Raymond Adams and Edward P. Richardson, Jr.  His "classmates" in the Charles Kubik Laboratory of Neuropathology at the Massachusetts General Hospital were Karl-Erik Astrom, Elliot Mancall, and Henry de F. Webster. 

Due to organizational problems at that time, the once-famous French school of neuropathology was in disarray, and young French scholars had to go to Adams's service at Harvard, Ludo van Bogaert's Institute at Antwerp, Belgium, or Harry Zimmerman's laboratory in New York to complete their training in this basic neurological discipline.  These obligatory trips had excellent consequences and contributed to the development of a core of French scientists  exposed to the international scientific community, like Lyon and his friend Jean Lapresle.  This combination of clinical training in France with international research exposure was especially valuable.  Research in Europe had not yet recovered from the war and was still comparatively weak, but clinical training remained excellent, especially in Paris.  Recruitment of patients was unlimited and directed into a very centralized health care delivery system.  In addition, the faculty, who had previously sustained difficult clinical competition (« les concours ») until age forty, were not pressured to publish superficial and repetitive papers but were allowed to concentrate fully on their clinical activities.  Thus, the French academic system had several weaknesses but also a number of advantages.
<>After such a long period of preparation, Lyon was appointed pediatric neurologist, neuropathologist, and « professeur agrégé » (associate professor)  at the Hôpital des En fants Malades and the Hôpital Saint Vincent de Paul. These hospitals, which belong to the Assistance Publique de Paris, are affiliated with the University of Paris Medical School and jointly, as extramural facilities, with the Institut National de la Santé et de la Recherche Médicale.  From the mid 1950s until the mid 1970s, Gilles Lyon, Jean Aicardi, Stéphane Thieffry, and Michel Arthuis were associated with the same service in Paris and had almost a complete monopoly on pediatric neurology in France.  This included the availability of both large numbers of children with neurological disorders and fellows interested in training, who were predominantly from French and Spanish-speaking countries.  Further, both Lyon and Aicardi had excellent international contacts with child neurologists in the English-speaking countries.

During the decades following World War II, the new French pediatric establishment, founded by Robert Debre, reorganized pediatrics and made important contributions in general pediatrics, public health, genetics, metabolic disorders, social pediatrics, and several pediatric subspecialties.  Pediatric neurology, after an initial period of growth in Paris under Thieffry’s chairmanship, did not remain a priority.  This occurred partly because pediatrics and neurology were separated by an "iron curtain," partly for local personai and organizational reasons and partly because certain powerful French pediatricians thought pediatric neurology could be indirectly covered with less disruption to the pediatric establishment by a combination of neurosurgery, genetics, metabolic diseases, and child psychiatry.  As leaders of world pediatric neurology, Lyon and Aicardi found it difficult to obtain funding and space to see patients and engage in research at a time when their clinical, tesearch, and teaching needs were dramatically increasing.  More recently, however, the attitude towards pediatric neurology has improved and the importance of this field and the need for its development are better appreciated.

The Université Catholique de Louvain (UCL), with two campuses in Belgium (the Medical School in Brussels and the nonmedical faculties in Louvain-la-Neuve), is among the oldest European Universities. During the past several decades, this institution, located at the center of the European community, has enjoyed excellent support, organisation, and superb academic freedom.  In 1969 1 was appointed to develop the Pediatric Neurology Unit at the UCL, and by 1975 this service had expanded substantially.  Transformation into an international center with new research facilities, to allow colleagues from clinical pediatric neurology and the developmental neurosciences to collaborate was proposed by myself.  At my request, Lyon was approached by the « president » (Recteur Edouard Massaux) of the university and by the dean of the medical school (Michel Meulders) to become director and chief of service of this new center.  Under my insistance, Gilles Lyon accepted this position, arriving in Brussels in 1976.  The service grew rapidly and now includes twenty-eight beds of acute pediatric neurology and eighty beds of pediatric neurology rehabilitation.  With our associates, we are responsable for sections on pediatric neurology, neuroanatomy, pediatric and developmental neuropathology, pediatric neuropsychology, and metabolic disorders at the medical school and academic hospital.  There are also programs in preventive medicine in child neurology, a section on developmental and fetal neuropathology, and a positron emission tomography program oriented towards pediatric neurology.  A general overview of the clinical and research contributions of this center reflecting the integration of clinical pediatric neurology and neuropathology is available in a recently published textbook (Lyon and Evrard, 1987).

It is probably of interest when reading these biographies on the founders of child neurology to compare the differences in pediatric neurology in different epochs and continents.  In this respect, one should mention that in most European pediatric neurology services, general care of the patient is provided by the child neurology staff.  Most of us were trained in general pediatrics and keep current in order to provide care for the child, infant, and newborn.  Lyon, like most child neurologists in Western Europe, has this daily responsibility.  This type of organization of a pediatric neurology service is burdensome but keeps us in close contact with the patients and their parents and provides other advantages for the development of pediatric neurology.  The appointment of the Frenchman Lyon as chairman in a Belgian university has been remarkably successful and is often quoted as an example to be followed at a time when the European community is officially trying improve the circulation of academic personnel among the different universities in Western Europe.

Lyon's major research contributions relate to the prenatal encephalopathies, perinatal neuropathology, viral infections of the central nervous system, and several clinicopathological correlations. Among his 150 publications, I shall cite only a few.

Lyon was among the first to demonstrate convincingly the role played by circulatory disturbances arising in the second half of pregnancy as the origin of prenatal brain disorders (Lyon and Robain, 1967).  He was the first to show that cytomegalovirus infection affects the fetal brain, particularly by creating a perfusion failure, not an arrest of neuronal migration (Marques-Dias et al, 1984).  His description, with Philippe Evrard and Marc Tardieu, of the pathophysiology and management of the progressive expanding porencephalies is widely accepted (1981).  In a seminal paper, Lyon established the existence of several "developmental microcephalies" (Robain and Lyon, 1972).  With the joint efforts of Philippe Evrard, Verne S. Caviness, Olivier Robain, and Roger Williams, during the past fifteen years he has established a framework for the pathogenetic classification of prenatal malformations.  More recently, Jean-François Gadisseux joined this international collaborative team.  For reviews explaining the evolution of the ideas in this field, to which Lyon has been a major contributor, see Evrard, Gadisseux, and Lyon, 1982; Caviness and Williams, 1984; and Evrard et al, 1989.

In perinatal neuropathology, Lyon first described the chronic lesions of periventricular leukomalacla as early as 1959 in a paper for which he was responsible for the neuropathology (Marie, Lyon, and Bargeton, 1959).  This original study has not been given sufficient recognition because it was published only in a French journal.

In neurovirology, he first described chronic rubella encephalitis (Lebon and Lyon, 1974) and the delayed type of acute measles encephalitis in immunosuppressed children (Lyon, 1972) and in immunocompetent children (Lyon, Ponsot, and Lebon, 1977).  He contributed to the knowledge of chronic encephalitis in X-linked hypogammaglobulinemia (Lyon, Griscelli, and Lebon, 1972; Lyon et al, 1980).  In a classic paper with Raymond Adams and Philip Dodge, he drew attention to the heterogeneous group of postviral noninflammatory acute encephalopathies of infancy (Lyon, Dodge, and Adams, 1961).  Some of these patients, but not all, were retrospectively found to be affected with Reye syndrome.

Among Lyon’s more general contributions, aside from his most recent textbook (Lyon and Evrard, 1987), he published with Raymond Adams the Neurology of Hereditary Metabolic Diseases of Children (Adams and Lyon, 1982). Alone or with other coauthors, Lyon contributed new information on many other clinicopathological problems.  He first described the in vivo diagnosis of metachromatic leukodystrophy by nerve biopsy (Thieffry and Lyon, 1959) and the importance of peripheral nerve involvement in this disease (Thieffry et al, 1964).  He described a new form of sialidosis (Le Sec, Stanescu, and Lyon, 1978), and with Thieffry, Arthuis, and Aicardi first reported the IgA deficiency in ataxia-telangiectasla (Thieffry et al, 1961).  He has also contributed to the description of the congenital hypomyelinating neuropathies.  The characteristic ultrastructure of these disorders is now frequently referred to as the "Lyon type" of onion bulbs (Lyon, 1969; Guzzetta, Ferrière, and Lyon, 1982).

Lyon has been a pioneer and a major contributor in the field of pediatric neurology.  He combines an outstanding knowledge of child neurology and neuropathology.  This now rarely combined competence has given him a strong and exceptional position.  He is an internationally recognized authority in developmental neuropathology, the continuing importance of which is now emphasized by all concerned in the developmental neurosciences.  With his powerful but liberal leadership, his influence has been effective, and he is among the creators of modern pediatric neurology in Western Europe.

Lyon was one of the founders of the Société Européenne de Neurologie Pédiatrique, a branch of the European Federation of Child Neurology Societies.  He has been, and remains, an inspiring master for dozens of pediatric neurologists throughout the world, who now have great responsibilities and internationally recognized positions.  In addition to his outstanding research contributions, he is well versed in literature, art, and architecture.  He has an extraordinary "internationalist charm," being one of the best symbols of French medicine for American colleagues, a lost pearl for the French brain hunters, a "French pediatric neurologist drinking no wine and no Scotch" for the British, and just a Belgian pediatric neurologist for us. Something else has made life easier and more meaningful for him; he has a marvelous and generous wife, trained first in law and afterwards in classical dance. She is a woman of culture and sophistication, and their marriage has been a source of happiness and affection for both of them.

For me, as for many other pediatric neurologists, Gilles Lyon is the best and most generous friend, always delighted to promote and eager to delegate, while remaining, for the important concerns, the most solid and final reference for his friends, colleagues, and associates.


Philippe Evrard (written in 1989)



  • Adams, R. D., and G. Lyon. 1982.  Neurology of Hereditary Metabolic Diseases of Children.  New York: McGraw-Hill.
  • Caviness, V. S., and R. Williams. 1984.  Normal and Abnormal Development of the Brain.  In Advances in Clinical Neuropsychology.  Vol. 2, 1-62.  Ed.  R. E. Tarter and G. Goldstein.  New York: Plenum.
  • Evrard, P., et al. 1989.  Pathology of Prenatal Encephalopathies.  In Child Neurology and Developmental Disabilities, 153-76.  Ed.  J. French et al.  Baltimore: Paul H. Brookes.
  • Evrard, P., J. F. Gadisseux, and G. Lyon. 1982.  Le développement prénatal du système nerveux et ses perturbations.  Prog néonat 4:63-106.
  • Guzzetta, F., G. Ferrière, and G. Lyon. 1982.  Congenital Hypomyelination Polyneuropathy.  Pathological Findings Compared to Polyneuropathies Starting Later in Life.  Brain 105:395-416.
  • Lebon, R, and G. Lyon. 1974.  Non-Congenital Chronic Rubella Encephalitis. Lancet 2:468.
  • Le Sec, C., R. Stanescu, and G. Lyon. 1978.  Un nouveau type de sialidose avec atteinte rénale: la néphrosialidose.  Etude anatomique.  Arch fran péd 35:83044.
  • Lyon, G. 1961. First Signs and Mode of Onset of Congenital Hemiplegia. Dev Med & Child Neur 4 :33-38.
  • Lyon, G. 1969. Ultrastructural Study of a Nerve Biopsy from a Case of Early Infantile Chronic Neuropathy. Acta Neuropath 13 : 131-142.
  • Lyon, G. 1972. Action des immunosuppresseurs sur une encéphalite virale (rougeole) : inhibition de la réaction inflammatoire. Comptes Rendus Académie des Sciences 274D : 1872-78.
  • Lyon G, PR Dodge, and RD Adams. 1961. The acute encephalopathies of obscure origin in infants. Brain 84 : 680.
  • Lyon, G., and P. Evrard. 1987. Neuropédiatrie. Masson Publ., Paris, 1987, 436 pages.
  • Lyon, G., et al. 1980.  Chronic Progressive Encephalitis in Children with XLinked Hypogammaglobulinemia.  Neuroped 11:57-71.
  • Lyon, G., C. Griscelli, and P. Lebon. 1972.  Endothelial intracisternal Tubular Inclusions in a Case of Chronic Encephalitis Associated with Immunological Deficiency.  Neuroped 3:459-69.
  • Lyon, G., G. Ponsot, and P. Lebon. 1977.  Acute Measles Encephalitis of the Delayed Type.  Ann Neur 2:322-27.
  • Lyon, G., and 0. Robain. 1967.  Etude comparative des encéphalopathies circulatoires prénatales et para-natales (hydranencéphalies, porencéphalies et encéphalomalacies kystiques de la substance blanche).  Acta Neuropath 9:79-88.
  • Marie, J., G. Lyon, and E. Bargeton. 1959.  La sclérose cérébrale centro-lobaire (syndrome de Little).  Presse méd 67:2286-89.
  • Marques-Dias, M. J., et al. 1984.  Prenatal Cytomegalovirus Disease and Cerebral Microgyria.  Evidence for Perfusion Failure, not Disturbance of Histogenesis, as the Major Cause of Fetal Cytomegalovirus Encephalopathy. NeuroPe,d 15:18-24.
  • Robain, O., and G. Lyon. 1972.  Les microencéphalies familiales par malformation cérébrale.  Etude anatomo-clinique.  Acta Neuropath 20:96-109.
  • Tardieu, M., P. Evrard, and G. Lyon. 1981.  Progressive Expanding Congenital Porencephalies: A Treatable Cause of Progressive Encephalopathy.  Pediatrics 68:198-202.
  • Thieffry, S., et al. 1961.  I:ataxie-télangiectasie.  Rev neur 105:390-405.
  • Thieffry, S., and G. Lyon. 1959 Diagnostic d'un cas de leucodystrophie métachromatique (type Scholz) par la biopsie d'un nerf périphérique.  Rev neur 100:425-56.
  • Thieffry, S., et al. 1964.  L’atteinte du système nerveux périphérique dans la leucodystrophie métachromatique.  Rev neur 110:5.