Park SE, et al. Korean J Radiol. 2017 Jul-Aug;18(4):710-721. https://doi.org/10.3348/kjr.2017.18.4.710

The objective of this study was to compare the capability of arterial, portal venous, and delayed phases of helical CT with that of iodized-oil CT for revealing nodular hepatocellular carcinomas.Forty-eight patients with nodular hepatocellular carcinomas underwent triphasic helical CT examination with 10-mm collimation at 10-mm/sec table speed. We injected 120 ml of contrast material (36 g of iodine) at the rate of 3 ml/sec. Arterial-phase, portal venous-phase, and delayed-phase images were obtained with 30-sec, 65-sec, and 360-sec delays, respectively. All 48 patients also underwent angiography and intraarterial infusion of iodized oil after helical CT; iodized-oil CT was performed about 2 weeks after infusion of iodized oil. Helical CT images were compared with iodized-oil CT images for revealing hepatic nodules.In 48 patients, 79 hepatocellular carcinomas were seen with iodized-oil CT. Using helical CT, the arterial phase revealed 68 lesions (86%), the portal venous phase revealed 53 lesions (67%), and...

Diagnostic and Interventional Radiology

Purpose: To assess patient radiation doses during diagnostic and therapeutic neurointerventional procedures from multiple centers and propose dose reference level (RL).Materials and Methods: Consecutive neurointerventional procedures, performed in 22 hospitals from December 2020 to June 2021, were retrospectively studied. We collected data from a sample of 429 diagnostic and 731 therapeutic procedures. Parameters including dose-area product (DAP), cumulative air kerma (CAK), fluoroscopic time (FT), and total number of image frames (NI) were obtained. RL were calculated as the 3rd quartiles of the distribution.Results: Analysis of 1160 procedures from 22 hospitals confirmed the large variability in patient dose for similar procedures. RLs in terms of DAP, CAK, FT, and NI were 101.6 Gy·cm2, 711.3 mGy, 13.3 minutes, and 637 frames for cerebral angiography, 199.9 Gy·cm2, 3,458.7 mGy, 57.3 minutes, and 1,000 frames for aneurysm coiling, 225.1 Gy·cm2, 1,590 mGy, 44.7 minutes, and 800 frames for stroke thrombolysis, 412.3 Gy·cm2, 4,447.8 mGy, 99.3 minutes, and 1,621.3 frames for arteriovenous malformation (AVM) embolization, respectively. For all procedures, the results were comparable to most of those already published. Statistical analysis showed male and presence of procedural complications were significant factors in aneurysmal coiling. Male, number of passages, and procedural combined technique were significant factors in stroke thrombolysis. In AVM embolization, a significantly higher radiation dose was found in the definitive endovascular cure group.Conclusion: Various RLs introduced in this study promote the optimization of patient doses in diagnostic and therapeutic interventional neuroradiology procedures. Proposed 3rd quartile DAP (Gy·cm2) values were 101.6 for diagnostic cerebral angiography, 199.9 for aneurysm coiling, 225.1 for stroke thrombolysis, and 412.3 for AVM embolization. Continual evolution of practices and technologies requires regular updates of RLs.