Abstract 157: Evaluating the Impact of Pre‐Procedural CTA on Fluoroscopy Time and Conversion Rates

Abstract

Introduction Cerebral angiography, essential in managing cerebrovascular disorders, exposes patients to ionizing radiation, with dose dependence on procedure complexity, patient's body habitus, and equipment used, raising safety concerns (1,2). Conversion from primary to secondary access site, influenced by anatomical variables, further increases procedure and fluoroscopy time (3). We propose using Computed Tomography Angiography (CTA) prior to DSA for anatomical insights, potentially reducing access site conversion, procedure time, and radiation dose/fluoroscopy time. This study evaluates the impact of pre‐procedural CTA on fluoroscopy time and access site conversion rates. Methods A retrospective chart review was conducted at a single center to collect data for this study. A total of 93 participants who received DSA were evaluated. Variables of interest included whether a CTA was performed prior to DSA, fluoroscopy time, fluoroscopy dose, time per vessel, dose per vessel, average number of vessels imaged, and the conversion rate from radial to femoral access. Descriptive statistics were used to summarize the data, and independent sample t‐tests were conducted to compare the means of continuous variables between the groups that received a CTA Neck prior to DSA and those that did not. All statistical analyses were performed using a significance level of 0.05. Results Out of 93 participants, 61 had a prior CTA neck and 32 did not. The non‐prior CTA group had slightly higher average fluoroscopy time (15.68 vs. 14.30 min, p=0.39) and dose (643.29 vs. 582.90, p=0.37), but lower time per vessel (3.42 vs. 3.65, p=0.58) and higher dose per vessel (162.80 vs. 145.01, p=0.63). They also imaged more vessels on average (4.81 vs. 4.33, p=0.09). Conversion percentage for non‐prior CTA was lower compared to the prior CTA group (6.25% vs. 6.56%) but not statistically significant. Standard deviation for all measures, except for time per vessel, was higher in the non‐prior CTA neck, indicating more variability in this group. Conclusion This retrospective analysis suggests that prior computed tomography angiography (CTA) might lead to reduced fluoroscopy times and dosage during procedures, but the results are not statistically significant at this stage. However, the study indicates that prior CTA cases had a higher percentage of access site conversions, though the sample size was small. Due to these findings, further investigation with a larger sample size is needed to explore these variables more thoroughly. If CTA before digital subtraction angiography (DSA) can indeed decrease procedure time, radiation exposure, and the need for access site conversion, it has the potential to significantly improve functional neurological outcomes. Moreover, it may reduce the occurrence of complications related to radiation exposure and decrease the overall costs associated with performing DSA and related neurointerventions.