Since its introduction in the early 1980's, magnetic resonance imaging has become a familiar part of the medical armamentarium available for the diagnosis of different conditions.  Its rapid diffusion has been documented in several countries, mostly developed. By 1993, there were more than 4,000 units worldwide. In the US alone,  over 2,700  were in use by 1997.  Similar information is less available for developing countries.

Like in many other countries, MRI is widely accepted, adopted and used in Thailand although there is still limited formal evidence of effectiveness in regard to its impact on patient management, particularly outside the hospital setting. This has lead to a significant growth of import of the MRI expensive equipment, which requires high initial capital investment cost and also incurs high maintenance costs, without an effective regulatory mechanism to control the procurement and distribution.  A study showed that the number of units installed in Thailand were 20 of which 75% in Bangkok. The proportion installed in the private sector was 60%. MRIs installed in Bangkok seem to be overutilized while those installed outside Bangkok are underutilized due to the lack of technical personnel which will result in additional costs. However, data on the efficient use of MRI and information on the equitable access to MRI is still lacking in Thailand.

This study will describe the present pattern of diffusion of MRI in Thailand to assess the factors that determine the pattern of diffusion. Given the present economic and financial decline in the South East Asian region the impact of this crisis in Thailand on the diffusion of MRI will be investigated. This information will result in policy recommendations.