Reversed C-arm projection for reduction of focal skin radiation exposure: experimental analysis and first clinical experience.

Radiodermatitis, predominantly over the right scapula, is a well-known complication of complex percutaneous coronary interventions (PCI). To reduce focal radiation exposure, we analyzed an inversed X-ray beam direction using a reversed C-arm position. On phantom experiment, we found that 130° right anterior oblique projection reduced skin dose over the right scapula by 98.2 % (P < 0.001) compared with conventional 50° left anterior oblique projection. A 73-year-old man with history of bypass surgery, multiple PCI and chronic radiodermatitis over the right scapula presented with recurrent chest pain. After successful PCI using the reversed C-arm projection, no aggravation of radiodermatitis was found.