Application of the Theory of Constraints to Radiology

The central principle of the theory of constraints is that in any complex system there are only a few constraints that limit the performance (ie, "throughput") of the system. These constraints are rate-limiting steps to throughput. Once the constraint or bottleneck is identified, resources are used to improve the utilization rate at the point of the constraint to make the process as productive as possible. Others in the organization also must work to maintain the high utilization rate at the constraint. Strategies such as buffers are used to increase throughput at the constraints. Although it was initially developed in manufacturing, the theory of constraints has been applied to many industries. By using the theory of constraints to evaluate the radiologic workflow, constraints can be identified through targeted process improvement projects for optimization at steps that affect the total throughput of the system. Constraints can be physical, such as equipment or space (eg, imaging units or recovery room beds), or related to personnel. Because radiology is currently in a resource-constrained environment, targeted interventions with highly effective processes could improve productivity or flow. Given the workforce shortages in radiology, determining whether the constraint is equipment- or personnel-related may lead to different improvement projects.