Rethy Chhem, or the Art of Listening to the Silence of Empires

An internationally renowned radiologist turned historian of medicine, and later a public servant, Dr Chhem Kieth Rethy embodies an unusual trajectory: that of a child of Phnom Penh who became a professor on four continents before returning to put his knowledge at the service of Cambodia, from radiology wards to the forgotten hospitals of Jayavarman VII.

Professor Chhem Kieth Rethy speaking at a conference. Photo CG

A medical calling born in Phnom Penh

Born in 1952 in Phnom Penh, Rethy Chhem embarked early on an academic path that would take him far from his native country. A medical doctor, he chose to specialise in radiology, a discipline he would practise and teach for close to thirty years. But his path did not stop at diagnostic imaging: he also earned a PhD in Education, followed by a second doctorate, in History — two disciplines that would go on to enrich and redirect his scientific career.

Thirty years of radiology, across the Americas, Europe and Asia

Rethy Chhem's academic career unfolded across several continents, over some thirty years. He taught radiology at McGill University in Canada, at the National University of Singapore, at the Medical University of Vienna in Austria, and at several Japanese institutions specialising in the medical consequences of the atomic bombings and the Fukushima accident, in Hiroshima, Nagasaki and Fukushima. He also chaired, for several years, the Department of Diagnostic Radiology and Nuclear Medicine at Western University, in Canada. This prolific career produced more than two hundred scientific articles and around twenty edited textbooks on radiology, paleoradiology and medical education, two of which deal specifically with the Fukushima nuclear accident.

When radiology meets Khmer archaeology

It was around the turn of the 2000s that Rethy Chhem's career took an unexpected turn. French archaeologist Christophe Pottier, then excavating the pre-Angkorian site of Prei Khmeng in Siem Reap province, sought his radiological expertise to study skeletons unearthed during the dig. Rethy Chhem performed CT scans of these ancient remains — a first encounter between modern medical imaging and Khmer archaeology that would durably steer his research toward paleoradiology, the discipline that applies medical imaging techniques to the study of ancient human remains.

This collaboration later led him to take part in the excavation of one of the one hundred and two hospitals that King Jayavarman VII had built across his empire at the end of the 12th century. The work carried out on this site helped establish the existence, under this builder-king's reign, of a free, structured healthcare system across the Khmer empire — a discovery that earned Rethy Chhem recognition in the field of the history of medicine in Southeast Asia, at the crossroads of radiology, archaeology and epigraphy.

From the International Atomic Energy Agency to Cambodian research

Between 2008 and 2014, Rethy Chhem held a senior position at the International Atomic Energy Agency (IAEA) in Vienna, where he directed the Division of Human Health. This role, at the intersection of nuclear science and public health, added a further dimension to an already singular profile — that of a physician turned science diplomat.

In 2014, he returned to Cambodia to take the helm of the Cambodia Development Resource Institute (CDRI), one of the country's leading development policy think tanks and a major research institute across the ASEAN region, ranked among the world's top 100 think tanks by the University of Pennsylvania. He remained there until 2019, a period during which he was also appointed, in 2018, special health advisor to Prime Minister Hun Sen.

Dr Rethy Chhem during an interview. Photo CG

From research to public office

In May 2019, Rethy Chhem took a further step when he was appointed, by royal decree, Minister Delegate attached to the Prime Minister, seconded to the Ministry of Foreign Affairs and International Cooperation. The following year, in August 2020, he was appointed Secretary of State at the newly created Ministry of Industry, Science, Technology and Innovation (MISTI), where he notably oversees the National Institute of Science, Technology and Innovation. He currently also holds the rank of Senior Minister and chairs Cambodia's Economic, Social and Cultural Council.

On the academic side, Rethy Chhem maintains close ties with several institutions worldwide, including the radiology faculties of Nagasaki, Hiroshima and Fukushima, as well as with think tanks devoted to international relations and science diplomacy, in Asia and in China.

A career at the crossroads of knowledge

From the medical scanner to pre-Angkorian tombs, from the corridors of the IAEA to those of the Cambodian government, Rethy Chhem's journey illustrates a conviction rarely stated so plainly: that medicine, history and development policy are not separate worlds, but paths that, patiently, end up converging.