Description:
<jats:sec><jats:title>Purpose</jats:title><jats:p>Trials of non-operative management (NOM) have become the standard of care for blunt splenic injury (BSI) in hemodynamically stable patients. However, there is a lack of consensus regarding the utility of follow-up CT exams and relevant CT features. The purpose of this study is to determine imaging predictors of splenectomy on follow-up CT using quantitative volumetric measurements.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Adult patients who underwent a trial of non-operative management (NOM) with follow-up CT performed for BSI between 2017 and 2019 were included (<jats:italic>n</jats:italic> = 51). Six patients (12% of cohort) underwent splenectomy; 45 underwent successful splenic salvage. Voxelwise measurements of splenic laceration, hemoperitoneum, and subcapsular hematoma were derived from portal venous phase images of admission and follow-up scans using 3D slicer. Presence/absence of pseudoaneurysm on admission and follow-up CT was assessed using arterial phase images. Multivariable logistic regression was used to determine independent predictors of decision to perform splenectomy.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Factors significantly associated with splenectomy in bivariate analysis incorporated in multivariate logistic regression included final hemoperitoneum volume (<jats:italic>p</jats:italic> = 0.003), final subcapsular hematoma volume (<jats:italic>p</jats:italic> = 0.001), change in subcapsular hematoma volume between scans (<jats:italic>p</jats:italic> = 0.09) and new/persistent pseudoaneurysm (<jats:italic>p</jats:italic> = 0.003). Independent predictors of splenectomy in the logistic regression were final hemoperitoneum volume (unit OR = 1.43 for each 100 mL change; 95% CI: 0.99–2.06) and new/persistent pseudoaneurysm (OR = 160.3; 95% CI: 0.91–28315.3). The AUC of the model incorporating both variables was significantly higher than AAST grading (0.91 vs. 0.59, <jats:italic>p</jats:italic> = 0.025). Mean combined effective dose for admission and follow up CT scans was 37.4 mSv.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>Follow-up CT provides clinically valuable information regarding the decision to perform splenectomy in BSI patients managed non-operatively. Hemoperitoneum volume and new or persistent pseudoaneurysm at follow-up are independent predictors of splenectomy.</jats:p></jats:sec>