Professor Nicolaas (Klass) Bom was born in 1937 at Velsen, the Netherlands. In 1961, he obtained his M.Sc.EE degree from the University of Technology at Delft. He worked as a naval officer at the Laboratory of Physics of RVO-TNO at the Hague and was subsequently involved in research on underwater acoustics at the Saclant Research Center of NATO at La Spezia, Italy for a period of six years.

In 1969 he joined the Thoraxcentre of Erasmus University Rotterdam, the Netherlands, to set up a diagnostic ultrasound research and development program. He obtained his Ph.D. in 1972 on the thesis "New Concepts in Echocardiography". In this thesis he was the first to describe linear array principles with practical results in cardiology. It also contained a chapter on phased array catheter-based real time imaging of heart and large vessels. Since 1974, he is Head of the Biomedical Engineering Group of the Thoraxcentre. He became Professor of Medical Ultrasound at the Interuniversity Cardiology Institute of the Netherlands (ICIN) in 1979, with a parallel appointment at the Erasmus University Rotterdam. In 1987, he received an honorary doctorate from the Technological Faculty of the University of Lund, Sweden, for his work and inventions in the field of echocardiography.

Prompted by the neccessity of improving cardiac diagnosis by looking at the moving heart structures, Professor Bom was responsible for the development of the real-time multi-element linear array scanner in the early 1970s. His initial design in 1971, which he applied for a Dutch patent, consisted of only 20 crystals (each 4mm x 10mm). The probe face was 80mm long and 10mm wide. It operated at a frequency of 2.25 or 4.5 MHz sweeping at a frame rate of 150f/sec. The axial resolution was 1.25 mm at 3MHz while the beam width at 6 cm was 1cm. This abeit simple and inadequate design at that time has evolved into the very sophisticated real-time scanners that are widely available today. In collaboration with the cardiologist Paul Hugenholtz and Dutch company Organon Teknika, they produced the "Multiscan System", one of the earliest commercial linear array scanner in the world (Aloka® in Japan in 1971 also produced their first linear array scanner), mainly aimed for cardiac investigations. The transducers operated at either 2.25 or 4.5 MHz, again with 20 crystals producing 20 scan lines. The lateral resolution of this improved version at a dynamic range of 10dB was 3.7 mm at 6 cm and 6 mm at 10 cm depth. It did not sell very well though because of its relatively primitive resolution and its inability to image abdominal structures adequately.


Working in conjunction with Professor Juiry W. Wladimiroff in the Obstetrics Department, they studied the safety of ultrasound in pregnancy and fetal and placental vascular hemodynamics. Later on in 1979 Organon Teknika produced the Minivisor, a miniaturised portable scanner incoporating focusing electronics which Wladimiroff thought would be useful for Obstetric bedside diagnosis and a screening purposes. Professor Bom has pioneered and worked on many important research projects, many of which are on transducer design, experimental echocardiography, the development of intraluminal, transoesophageal and intravascular ultrasonic techniques, their clinical applications and standardization.

Professor Bom is also a member of the Board and the Executive Scientific Committee of the European Society of Cardiology. Since 1983, he is also a member of the Scientific Board and co-director of the Interuniversity Cardiology Institute of the Netherlands. In 1993, he became a Member (by appointment of H.M. the Queen of The Netherlands) of the Royal Dutch Academy of Sciences. In 1999 Professor Bom was elected Foreign Member of The Royal Academy of Engineering.

Besides his membership of several scientific societies, Professor Bom is on the Editorial Board of a number of journals in the field of ultrasound. He authored and co-authored over 300 scientific papers on the subject of design and development of ultrasonic devices for medical diagnostics, the physical principles related thereto and ultrasonic imaging techniques. Because of this pioneer work he was presented with the "History of Medical Ultrasound Pioneer Award" from the World Federation of Ultrasound in Medicine and Biology (WFUMB) in 1988 and more recently the Ian Donald Gold Medal for Technical Merit from the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) in 1997. His current research interest is in the refinement of intraluminal and intravascular ultrasound devices, methodology and standards.






* from "Technology of Real-time Ultrasound" by N. Bom - in Real-time Ultrasound in Perinatal Medicine. Ed. R. Chef, 1979.



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