Ultra–Low Radiation Dose CT Fluoroscopy for Percutaneous Interventions: A Porcine Feasibility Study

Abstract

To determine the feasibility of ultra-low-dose (ULD) CT fluoroscopy for performing percutaneous CT-guided interventions in an in vivo porcine model and to compare radiation dose, spatial accuracy, and metal artifact for conventional CT versus CT fluoroscopy. Materials and Methods: An in vivo swine model was used (n = 4, ~50 kg) for 20 procedures guided by 246 incremental conventional CT scans (mean, 12.5 scans per procedure). The procedures were approved by the Institutional Animal Care and Use Committee and performed by two experienced radiologists from September 7, 2017, to August 8, 2018. ULD CT fluoroscopic acquisitions were simulated by using only two of 984 conventional CT projections to locate and reconstruct the needle, which was superimposed on a previously acquired and motion-compensated CT scan. The authors (medical physicists) compared the ULD CT fluoroscopy results to those of conventional CT for needle location, radiation dose, and metal artifacts using Deming regression and generalized mixed models. Results: The average distance between the needle tip reconstructed using conventional CT and ULD CT fluoroscopy was 1.06 mm. Compared with CT fluoroscopy, the estimated dose for a percutaneous procedure, including planning acquisitions, was 0.99 mSv (21% reduction) for patients (effective dose) and 0.015 µGy (97% reduction) for physicians (scattered dose in air). Metal artifacts were statistically significantly reduced (P , .001, bootstrapping), and the average registration error of the motion compensation was within 1-3 mm. Conclusion: Ultra-low-dose CT fluoroscopy has the potential to reduce radiation exposure for intraprocedural scans to patients and staff by a factor of approximately 500 times compared with conventional CT acquisition, while maintaining image quality without metal artifacts.

Radiation Exposure Reduction of CT Fluoroscopy in Targeting Celiac Plexus for Neurolysis in Chronic Pain Management

“…Although the use of CT fluoroscopy carries the hazard of radiation exposure to the patient and operator, the recently used ultra-low dose exposure during the procedure decreased the radiation hazard concern. It provides practitioners with reliable information on the needle position with the real time imaging and the multiplanar reconstruction that makes it less operator dependent, more accurate and less time-consuming tool of guidance than the previously mentioned methods [11] .…”

Helical CT Reconstruction from Sparse-view Data through Exploiting the 3D Anatomical Structure Sparsity

“…ASIR of GE Healthcare, SAFIRE of Siemens Healthcare) have been released by the vendors [8]. Moreover, several studies suggested that IR can provide the image with better diagnostic performance against the conventional FBP algorithm at lower radiation dose [8], [11]. The effectiveness of IR depends on two major concerns in practice: the proper prior assumptions and optimization algorithms.…”

“…Among these, the low-mAs technique has been successfully used in commercial CT systems [8]. However, when the mAs is reduced to ultra-low-dose levels, e.g., tube currents of 10 to 20 mA and exposure time of 0.5 seconds per rotation, photon starvation and electronic noise can pose big challenges to image reconstruction [9], [10], [11].…”

Ultralow dose computed tomography protocol for hook‐wire localization of solitary pulmonary nodules prior to video‐assisted thoracoscopic surgery

“…Moreover, ultralow dose CT protocol has been successfully applied in CT‐guided interventional procedures (e.g. chest biopsy), with high diagnostic accuracy and safety …”

“…chest biopsy), with high diagnostic accuracy and safety. 8,9 Hook-wire localization (HWL) is currently the most commonly used technique for small lung nodule localization prior to video-assisted thoracoscopic surgery (VATS). 10,11 Presurgical localization of unpalpable nodules can precisely guide surgeons, whereas repetitive CT scanning was previously necessary.…”