Radiology usage worldwide

Dr Arpan K Banerjee  MBBS(LOND) FRCP, FRCR FBIR  Former President Radiology Section Royal Society of Medicine , Chair British Society for the History of Radiology

Since the dawn of medical imaging in 1895 following Roentgen’s great discovery of X-rays, and Becquerel’s discovery of radioactivity advances in medical imaging have continued at a relentless pace. Plain film, fluoroscopy, angiography and contrast media developed in the first half of the twentieth century and then giant strides were made with the invention of the CT scanner by Hounsfield, ultrasound and more recently MRI imaging in the latter half of the twentieth century. Today advances are being made in minimally invasive therapies and molecular imaging which will hopefully lead to better outcomes in cancer diagnosis and treatments. All these advances come at a cost. Workloads increase annually in radiology departments around the world with staff unable to keep up with workloads and recruitment problems seen in many parts of the world. The increasing number of investigations per patient and the complexity of the investigations have contributed to the workloads worldwide. In developing countries the demand for radiology also continues to increase with the increasingly sophisticated public demanding more tests rather than being reassured by the words of the paternalistic physician. A wide disparity exists around the world regarding the access to appropriate medical imaging.

Today medical procedures account for a significant proportion of the collective effective dose of radiation that we are being exposed to with the dose levels having increased significantly from the 1980’s partly fuelled by the exponential rise in CT scan usage. In most cases the investigations usefulness outweighs the harm but the increased usage needs to be carefully checked.

In the early days of CT scanning 1-3 procedures per 1000 population were performed in the USA with the figure now more than 40.

Developing countries like India are also seeing a greater usage of imaging procedures especially in the urban middle class population. These figures are only likely to increase in the future with increased economic development.

Doctors and radiologists of the future need to be mindful of the over reliance and over usage of these technologies. Apart from the radiation issues harm can be done by the discovery of lesions no-one understands ‘the incidentalomas’ leading to further unnecessary and potential harmful procedures such as biopsies. Also there is a law of diminishing returns when the number of investigations gets excessive with a greater risk of harm and economic damage to the health systems involved. A careful balance needs to be achieved. Radiologists and referring physicians need to use evidence based data to justify their investigations and if little is added then doing the test should be questioned. Imaging must not become a commodity in our consumerist age. We must continue the age old Oslerian traditions of speaking to and examining our patients and not forget Hippocrates dictum ‘Primum non nocere’ (First do no harm).


  • DOI:  Radiologic and Nuclear Medicine Studies in the United States and Worldwide: Frequency, Radiation Dose, and Comparison with Other Radiation Sources—1950–2007
  • Fred A. Mettler,  et al Radiology 2009