Saline optical coherence tomography in percutaneous coronary intervention: Practical considerations and technical guidance

Optical coherence tomography (OCT) is a high-resolution intravascular imaging modality that provides detailed assessment of plaque morphology, stent optimization and procedural complications during percutaneous coronary intervention (PCI). Conventional OCT requires injection of contrast for blood clearance during image acquisition, which can increase the risk of contrast-induced nephropathy particularly in patients with renal dysfunction. Saline-based OCT has emerged as an alternative strategy to reduce contrast exposure, with available data supporting its safety and diagnostic quality in a substantial proportion of cases. However, its adoption remains limited, largely due to technical challenges in achieving adequate blood clearance with saline. This review article aims to outline the differences in physical properties between saline and contrast, highlights practical technical considerations for saline-based OCT acquisition, and proposes strategies for workflow integration in contemporary PCI practice.