JOHN MALLARD

English physicist (January 14, 1927-February 25, 2021), who played a crucial role in the development of two of the most important medical technologies of the present era: magnetic resonance imaging and positron emission tomography, as well as in the evolution and progress of medical physics.

Born in Kingsthorpe, Northampton, England, he obtained his physics degree from University College Nottingham, then part of the University of London, completing his research project on the magnetic properties of uranium in 1947 under the tutelage of Professor Leslie Fleetwood Bates.

He worked as an "assistant physicist" at the Liverpool Radium Institute where he completed his training as a hospital physicist, later joining the Hammersmith Hospital and Post Graduate Medical School in 1953. Together with C. J. Peachy he developed in 1959 the first whole-body isotopic scanner in the United Kingdom, whose first diagnosis was that of a brain tumor.

In 1964 he published his theories on electron spin resonance and its possible applications for medical purposes in the prestigious journal Nature, although these initial observations were not taken into account for a long time. A year later, he became head of the Chair of Medical Physics at the University of Aberdeen, where in his first lecture he predicted the important role that positron emission tomography would play in the diagnosis of various medical pathologies.

Mallard brought to Scotland, through a nationally popular subscription, the first positron emission tomography device, which was located at the Woodend Hospital, which today has become the John Mallard PET Centre at the Aberdeen Royal Infirmary.

During the 70s, Professor Mallard coordinated a team of specialists led by Dr. Jim Hutchinson, who developed a magnetic resonance scanner (0.04 Tesla) that was used for the study of laboratory animals. This same team developed the first whole-body resonance scanner, which diagnosed its first patient on April 26, 1980.

During the 80s, his team implemented the "spin warp imaging" technique that allowed the acquisition of three-dimensional images eliminating the artifacts produced by the patient's movement, and at the end of this same decade developed the color image, but they had to return to the grayscale image because radiologists were not used to handling color.

He retired from the University of Aberdeen in 1992 and remained very active, cooperating in the international development of medical physics and biomedical engineering. He was the Founding President of the International Union of Physical and Engineering Sciences in Medicine (IUPESM), as well as the President of the International Organization for Medical Physics (IOMP). From this position he carried out the first attempt to achieve the recognition of medical physics and biomedical engineering by the International Council of Scientific Unions.

In 1992, he was nominated Officer of the Order of the British Empire, the IUPESM awarded him its first “Fellowship for International Leadership,” and in 2016 the IOMP established the “John Mallard Award” that rewards the medical physicist who has developed a high-quality scientific innovation with application in clinical practice. The American Association of Physicists in Medicine awarded him the “Landau Memorial Plaque.”

He is considered one of the scientists who has contributed the most to the establishment and development of medical physics as an academic discipline.

Author:
Dr. Luis Humberto Ros

JOHN MALLARD

Físico inglês (14 de janeiro de 1927-25 de fevereiro de 2021), que desempenhou um papel crucial no desenvolvimento de duas das mais importantes tecnologias médicas da atualidade: a ressonância magnética e a tomografia por emissão de pósitrons, bem como na evolução e no progresso da física médica.

Nascido em Kingsthorpe, Northampton, Inglaterra, ele se formou em física na University College Nottingham, então parte da Universidade de Londres, concluindo seu projeto de pesquisa sobre as propriedades magnéticas do urânio em 1947 sob a tutela do professor Leslie Fleetwood Bates.

Ele trabalhou como físico assistente no Liverpool Radium Institute, onde completou seu treinamento como físico hospitalar e, posteriormente, ingressou no Hammersmith Hospital e na Post Graduate Medical School em 1953. Juntamente com C. J. Peachy, ele desenvolveu o primeiro scanner de isótopos de corpo inteiro do Reino Unido em 1959, cujo primeiro diagnóstico foi um tumor cerebral.

Já em 1964, ele publicou suas teorias sobre ressonância de spin de elétrons e suas possíveis aplicações para fins médicos na prestigiada revista Nature, embora essas observações iniciais não tenham sido levadas em consideração por muito tempo. Um ano depois, tornou-se chefe da cadeira de Física Médica da Universidade de Aberdeen, onde, em sua primeira palestra, previu o importante papel que a tomografia por emissão de pósitrons desempenharia no diagnóstico de várias patologias médicas.

Mallard trouxe à Escócia, por meio de uma assinatura popular em nível nacional, o primeiro aparelho de tomografia por emissão de positrões, que foi instalado no Woodend Hospital, que hoje se tornou o John Mallard PET Centre no Aberdeen Royal Infirmary.

Durante a década de 70, o Professor Mallard coordenou uma equipe de especialistas liderada pelo Dr. Jim Hutchinson, que desenvolveu um scanner de ressonância magnética (0,04 Tesla) que foi utilizado para o estudo de animais de laboratório. Esta mesma equipe desenvolveu o primeiro scanner de ressonância de corpo inteiro, que diagnosticou seu primeiro paciente em 26 de abril de 1980.

During the 80s, his team implemented the "spin warp imaging" technique that allowed the acquisition of three-dimensional images eliminating the artifacts produced by the patient's movement, and at the end of this same decade developed the color image, but they had to return to the grayscale image because radiologists were not used to handling color.

Ele se aposentou da University of Aberdeen em 1992 e permaneceu muito ativo, cooperando no desenvolvimento internacional da física médica e da engenharia biomédica. Foi o Presidente Fundador da International Union of Physical and Engineering Sciences in Medicine (IUPESM), bem como Presidente da International Organization for Medical Physics (IOMP). A partir dessa posição, ele realizou a primeira tentativa de obter o reconhecimento da física médica e da engenharia biomédica pelo International Council of Scientific Unions.

Em 1992, ele foi nomeado Officer of the Order of the British Empire, a IUPESM lhe concedeu sua primeira “Fellowship for International Leadership”, e em 2016 a IOMP estabeleceu o “John Mallard Award” que premia o físico médico que tenha desenvolvido uma inovação de alta qualidade científica com aplicação na prática clínica. A American Association of Physicists in Medicine lhe concedeu a “Landau Memorial Plaque”.

Ele é considerado um dos cientistas que mais contribuiu para o estabelecimento e desenvolvimento da física médica como disciplina acadêmica.

Autor:
Dr. Luis Humberto Ros