Background <p>Accurate preoperative assessment of glenoid bone loss is critical in revision shoulder arthroplasty. The aim of this study was to evaluate the reliability of the Blueprint Revision 3D-CT planning software (Stryker, Kalamazoo, MI, USA) by comparing preoperative reconstructions with intraoperative findings. Agreement between preoperative and intraoperative assessments was analyzed for glenoid containment status, comparing 2D-CT and 3D reconstructed images derived from CT imaging (3D-CT) with intraoperative findings.</p> Methods <p>Forty-seven patients undergoing revision of the same stemless anatomic total shoulder arthroplasty with a cemented polyethylene glenoid component were included in this analysis. Glenoid bone defects were classified using the established systems according to Antuña and Williams-Iannotti. Defect containment (contained vs. uncontained) was assessed preoperatively using 3D-CT and 2D-CT imaging and compared with intraoperative findings. Agreement between different imaging methods was evaluated using Cohen’s kappa coefficient (κ).</p> Results <p>The most common indication for revision was glenoid loosening (79%), with a mean time to revision of 7 ± 3 years. Intraoperative evaluation classified 68.1% of glenoid defects as contained, which was correctly depicted in 80.9% of 3D-CT and 65.9% of 2D-CT. Agreement between 3D-CT and intraoperative findings was moderate (κ = 0.58, 80.9%) and outperformed 2D-CT (κ = 0.37, 65.9%). Agreement between 3D-CT and 2D-CT was also moderate (κ = 0.48, 72.3%).</p> Conclusion <p>3D-CT–based preoperative planning using Blueprint Revision demonstrates higher agreement with intraoperative findings compared to traditional 2D imaging. These findings support the value of advanced 3D planning tools in evaluating glenoid containment and guiding surgical decision-making in revision shoulder arthroplasty.</p>