Background: Manufacturers have provided C-arm CT imaging technologies for applications in interventional radiology in recent years. However, clinical imaging protocols and radiation doses have not been well studied or reported.
Objective: The purpose of this study is to develop low-dose settings for clinically acceptable CT imaging of temporomandibular joint in interventional radiology suites, using a C-arm imaging angiography system.
Materials and methods: CT scans were performed with a flat-panel digital C-arm angiographic system on a 5-year-old anthropomorphic phantom. The CTDI was determined for various rotation times, dose settings and Cu filter selections. The CTDI values were compared with those of conventional low-dose CT for the same phantom. The effectiveness of using Cu filters to reduce dose was also investigated. Images were reviewed by a senior radiologist for clinical acceptance.
Results: The manufacturer's default setting gave an equivalent CTDI of 4.8 mGy. Optimizing the dose settings and adding copper filtration reduced the radiation dose by 94%. This represents a 50% reduction from conventional CT.
Conclusion: Use of Cu filters and low-dose settings significantly reduced radiation dose from that of standard settings. This phantom study process successfully guided the clinical implementation of low-dose studies for all ages at our institution.