Investigation of Fluoroscopy Time and Radiation Dose by the Number of Cerebral Angiography Operator Experiences

We investigated the fluoroscopy time (FT) and radiation dose by the number of cerebral angiography (CA) operator experiences to clarify the learning curve of CA.

The subjects were cases for whom CA was performed at our hospital for 5 years between April 2015 and March 2020. Based on the number of CA operator experiences, they were classified into four groups: 1-50 cases (group A), 51-100 cases (group B), 101-200 cases (group C), and 201 cases and later (group D). The FT and radiation dose were retrospectively investigated.

Of the 865 consecutive CA cases, 293 cases for follow-up, i.e. after treatment, 54 for arteriovenous shunt diseases, 21 lacking data, and 1 case requiring intervention for thrombosis during CA were excluded. In total, 496 CA cases were investigated. There were 61 cases in group A, 56 cases in group B, 44 cases in group C, and 335 cases in group D, and there was no significant difference in patient background factors among the groups. The median FT and radiation dose (interquartile range) in each group were 20.2 min (14.6) and 374 mGy (185.3) in group A, 14.8 min (12.1) and 366 mGy (167.9) in group B, 10.8 min (6) and 320 mGy (151.7) in group C, and 9.4 min (6.4) and 336 mGy (171) in group D. The FT was significantly shorter in group C than in group A, and significantly shorter in group D than in groups A, B, and C. The radiation dose was significantly lower in groups C and D than in groups A and B.

This study suggested that CA can be performed alone after experiencing approximately 100 cases as an operator.