Design of high resolution collimators for small gamma cameras

A realistic Monte Carlo computer model for designing and optimising gamma camera collimators has been used to design high resolution collimators which can accommodate the resolving potential of the small gamma camera. The performance of the collimator is a key factor in determining the overall imaging performance of the system. Three materials have been investigated; lead, tungsten and lead glass. The results demonstrate that tungsten is the preferred material, due to its attenuating properties. Furthermore, its other properties, such as strength, would allow thin, durable collimators to be constructed. Lead has a slight reduction in imaging performance and its malleability could prove problematic in thin septa construction. Lead glass was selected due to the relative ease of constructing very narrow septa. It has been shown to have potential, however the collimator performance is degraded compared with the other materials.